[core] Switch from background to foreground placement

 - Background placement code now just generates static symbol buffers
 - Don't render GeometryTiles until their symbols are loaded. This is necessary for the CrossTileSymbolIndex to successfully prevent flicker.
 - SymbolInstances are transferred to SymbolBucket for use on foreground during collision detection
 - Symbols are sorted on foreground by sorting their index buffer but leaving vertex buffers intact (only works within one segment)
 - Vertical glyphs are generated at same time as horizontal glyphs. `reprojectLineLabels` chooses which one to use at render time and hides the other.
 - Icons are now always represented with a single collision box, even if they're placed along a line (this means their rotation alignment may be wrong, but the approach of representing them with multiple collision boxes wasn't very accurate either).
 - Generate vertices for new debug collision boxes and collision circles
 - Only add symbols within tile boundaries (reduces work, avoids double-draw)
 - Update symbol_projection.cpp to support line label projection calls from CollisionIndex.

21 files changed, 697 insertions, 431 deletions

diff --git a/src/mbgl/layout/symbol_instance.cpp b/src/mbgl/layout/symbol_instance.cpp
index 02fb800df6..d0398fcd30 100644
--- a/src/mbgl/layout/symbol_instance.cpp
+++ b/src/mbgl/layout/symbol_instance.cpp
@@ -11,7 +11,6 @@ SymbolInstance::SymbolInstance(Anchor& anchor_,
                                optional<PositionedIcon> shapedIcon,
                                const SymbolLayoutProperties::Evaluated& layout,
                                const float layoutTextSize,
-                               const bool addToBuffers,
                                const uint32_t index_,
                                const float textBoxScale,
                                const float textPadding,
@@ -19,11 +18,12 @@ SymbolInstance::SymbolInstance(Anchor& anchor_,
                                const std::array<float, 2> textOffset_,
                                const float iconBoxScale,
                                const float iconPadding,
-                               const SymbolPlacementType iconPlacement,
                                const std::array<float, 2> iconOffset_,
                                const GlyphPositionMap& positions,
                                const IndexedSubfeature& indexedFeature,
-                               const std::size_t featureIndex_) :
+                               const std::size_t featureIndex_,
+                               const std::u16string& key_,
+                               const float overscaling) :
     anchor(anchor_),
     line(line_),
     index(index_),
@@ -31,25 +31,22 @@ SymbolInstance::SymbolInstance(Anchor& anchor_,
     hasIcon(shapedIcon),
 
     // Create the collision features that will be used to check whether this symbol instance can be placed
-    textCollisionFeature(line_, anchor, shapedTextOrientations.second ?: shapedTextOrientations.first, textBoxScale, textPadding, textPlacement, indexedFeature),
-    iconCollisionFeature(line_, anchor, shapedIcon, iconBoxScale, iconPadding, iconPlacement, indexedFeature),
+    textCollisionFeature(line_, anchor, shapedTextOrientations.first, textBoxScale, textPadding, textPlacement, indexedFeature, overscaling),
+    iconCollisionFeature(line_, anchor, shapedIcon, iconBoxScale, iconPadding, SymbolPlacementType::Point, indexedFeature),
     featureIndex(featureIndex_),
     textOffset(textOffset_),
-    iconOffset(iconOffset_) {
+    iconOffset(iconOffset_),
+    key(key_) {
 
     // Create the quads used for rendering the icon and glyphs.
-    if (addToBuffers) {
-        if (shapedIcon) {
-            iconQuad = getIconQuad(*shapedIcon, layout, layoutTextSize, shapedTextOrientations.first);
-        }
-        if (shapedTextOrientations.first) {
-            auto quads = getGlyphQuads(shapedTextOrientations.first, layout, textPlacement, positions);
-            glyphQuads.insert(glyphQuads.end(), quads.begin(), quads.end());
-        }
-        if (shapedTextOrientations.second) {
-            auto quads = getGlyphQuads(shapedTextOrientations.second, layout, textPlacement, positions);
-            glyphQuads.insert(glyphQuads.end(), quads.begin(), quads.end());
-        }
+    if (shapedIcon) {
+        iconQuad = getIconQuad(*shapedIcon, layout, layoutTextSize, shapedTextOrientations.first);
+    }
+    if (shapedTextOrientations.first) {
+        horizontalGlyphQuads = getGlyphQuads(shapedTextOrientations.first, layout, textPlacement, positions);
+    }
+    if (shapedTextOrientations.second) {
+        verticalGlyphQuads = getGlyphQuads(shapedTextOrientations.second, layout, textPlacement, positions);
     }
 
     if (shapedTextOrientations.first && shapedTextOrientations.second) {
diff --git a/src/mbgl/layout/symbol_instance.hpp b/src/mbgl/layout/symbol_instance.hpp
index f1df416cd1..827a5dbbdb 100644
--- a/src/mbgl/layout/symbol_instance.hpp
+++ b/src/mbgl/layout/symbol_instance.hpp
@@ -5,6 +5,7 @@
 #include <mbgl/text/collision_feature.hpp>
 #include <mbgl/style/layers/symbol_layer_properties.hpp>
 
+
 namespace mbgl {
 
 class Anchor;
@@ -18,7 +19,6 @@ public:
                    optional<PositionedIcon> shapedIcon,
                    const style::SymbolLayoutProperties::Evaluated&,
                    const float layoutTextSize,
-                   const bool inside,
                    const uint32_t index,
                    const float textBoxScale,
                    const float textPadding,
@@ -26,18 +26,20 @@ public:
                    const std::array<float, 2> textOffset,
                    const float iconBoxScale,
                    const float iconPadding,
-                   style::SymbolPlacementType iconPlacement,
                    const std::array<float, 2> iconOffset,
                    const GlyphPositionMap&,
                    const IndexedSubfeature&,
-                   const std::size_t featureIndex);
+                   const std::size_t featureIndex,
+                   const std::u16string& key,
+                   const float overscaling);
 
     Anchor anchor;
     GeometryCoordinates line;
     uint32_t index;
     bool hasText;
     bool hasIcon;
-    SymbolQuads glyphQuads;
+    SymbolQuads horizontalGlyphQuads;
+    SymbolQuads verticalGlyphQuads;
     optional<SymbolQuad> iconQuad;
     CollisionFeature textCollisionFeature;
     CollisionFeature iconCollisionFeature;
@@ -45,6 +47,12 @@ public:
     std::size_t featureIndex;
     std::array<float, 2> textOffset;
     std::array<float, 2> iconOffset;
+    std::u16string key;
+    bool isDuplicate;
+    optional<size_t> placedTextIndex;
+    optional<size_t> placedVerticalTextIndex;
+    optional<size_t> placedIconIndex;
+    uint32_t crossTileID = 0;
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/layout/symbol_layout.cpp b/src/mbgl/layout/symbol_layout.cpp
index 2c90b69b08..09d8883544 100644
--- a/src/mbgl/layout/symbol_layout.cpp
+++ b/src/mbgl/layout/symbol_layout.cpp
@@ -8,7 +8,6 @@
 #include <mbgl/renderer/image_atlas.hpp>
 #include <mbgl/style/layers/symbol_layer_impl.hpp>
 #include <mbgl/text/get_anchors.hpp>
-#include <mbgl/text/collision_tile.hpp>
 #include <mbgl/text/shaping.hpp>
 #include <mbgl/util/constants.hpp>
 #include <mbgl/util/utf.hpp>
@@ -43,8 +42,8 @@ SymbolLayout::SymbolLayout(const BucketParameters& parameters,
                            std::unique_ptr<GeometryTileLayer> sourceLayer_,
                            ImageDependencies& imageDependencies,
                            GlyphDependencies& glyphDependencies)
-    : sourceLayer(std::move(sourceLayer_)),
-      bucketName(layers.at(0)->getID()),
+    : bucketName(layers.at(0)->getID()),
+      sourceLayer(std::move(sourceLayer_)),
       overscaling(parameters.tileID.overscaleFactor()),
       zoom(parameters.tileID.overscaledZ),
       mode(parameters.mode),
@@ -179,7 +178,8 @@ bool SymbolLayout::hasSymbolInstances() const {
 }
 
 void SymbolLayout::prepare(const GlyphMap& glyphMap, const GlyphPositions& glyphPositions,
-                           const ImageMap& imageMap, const ImagePositions& imagePositions) {
+                           const ImageMap& imageMap, const ImagePositions& imagePositions,
+                           const OverscaledTileID& tileID, const std::string& sourceID) {
     const bool textAlongLine = layout.get<TextRotationAlignment>() == AlignmentType::Map &&
         layout.get<SymbolPlacement>() == SymbolPlacementType::Line;
 
@@ -248,7 +248,7 @@ void SymbolLayout::prepare(const GlyphMap& glyphMap, const GlyphPositions& glyph
 
         // if either shapedText or icon position is present, add the feature
         if (shapedTextOrientations.first || shapedIcon) {
-            addFeature(std::distance(features.begin(), it), feature, shapedTextOrientations, shapedIcon, glyphPositionMap);
+            addFeature(std::distance(features.begin(), it), feature, shapedTextOrientations, shapedIcon, glyphPositionMap, tileID, sourceID);
         }
         
         feature.geometry.clear();
@@ -261,7 +261,9 @@ void SymbolLayout::addFeature(const std::size_t index,
                               const SymbolFeature& feature,
                               const std::pair<Shaping, Shaping>& shapedTextOrientations,
                               optional<PositionedIcon> shapedIcon,
-                              const GlyphPositionMap& glyphPositionMap) {
+                              const GlyphPositionMap& glyphPositionMap,
+                              const OverscaledTileID& tileID,
+                              const std::string& sourceID) {
     const float minScale = 0.5f;
     const float glyphSize = 24.0f;
     
@@ -288,12 +290,10 @@ void SymbolLayout::addFeature(const std::size_t index,
     const SymbolPlacementType textPlacement = layout.get<TextRotationAlignment>() != AlignmentType::Map
                                                   ? SymbolPlacementType::Point
                                                   : layout.get<SymbolPlacement>();
-    const SymbolPlacementType iconPlacement = layout.get<IconRotationAlignment>() != AlignmentType::Map
-                                                  ? SymbolPlacementType::Point
-                                                  : layout.get<SymbolPlacement>();
+
     const float textRepeatDistance = symbolSpacing / 2;
-    IndexedSubfeature indexedFeature = { feature.index, sourceLayer->getName(), bucketName,
-                                         symbolInstances.size() };
+    IndexedSubfeature indexedFeature(feature.index, sourceLayer->getName(), bucketName, symbolInstances.size(),
+                                     sourceID, tileID.canonical.z, tileID.canonical.x, tileID.canonical.y);
 
     auto addSymbolInstance = [&] (const GeometryCoordinates& line, Anchor& anchor) {
         // https://github.com/mapbox/vector-tile-spec/tree/master/2.1#41-layers
@@ -314,14 +314,16 @@ void SymbolLayout::addFeature(const std::size_t index,
 
         if (avoidEdges && !inside) return;
 
-        const bool addToBuffers = mode == MapMode::Still || withinPlus0;
-
-        symbolInstances.emplace_back(anchor, line, shapedTextOrientations, shapedIcon,
-                layout.evaluate(zoom, feature), layoutTextSize,
-                addToBuffers, symbolInstances.size(),
-                textBoxScale, textPadding, textPlacement, textOffset,
-                iconBoxScale, iconPadding, iconPlacement, iconOffset,
-                glyphPositionMap, indexedFeature, index);
+        // TODO set this to make api-gl work
+        const bool singleTileMode = false && mode == MapMode::Still;
+        if (singleTileMode || withinPlus0) {
+            symbolInstances.emplace_back(anchor, line, shapedTextOrientations, shapedIcon,
+                    layout.evaluate(zoom, feature), layoutTextSize,
+                    symbolInstances.size(),
+                    textBoxScale, textPadding, textPlacement, textOffset,
+                    iconBoxScale, iconPadding, iconOffset,
+                    glyphPositionMap, indexedFeature, index, feature.text ? *feature.text : std::u16string{}, overscaling);
+        }
     };
     
     const auto& type = feature.getType();
@@ -392,108 +394,93 @@ bool SymbolLayout::anchorIsTooClose(const std::u16string& text, const float repe
     return false;
 }
 
-std::unique_ptr<SymbolBucket> SymbolLayout::place(CollisionTile& collisionTile) {
-    auto bucket = std::make_unique<SymbolBucket>(layout, layerPaintProperties, textSize, iconSize, zoom, sdfIcons, iconsNeedLinear);
-
-    // Calculate which labels can be shown and when they can be shown and
-    // create the bufers used for rendering.
-
-    const SymbolPlacementType textPlacement = layout.get<TextRotationAlignment>() != AlignmentType::Map
-                                                  ? SymbolPlacementType::Point
-                                                  : layout.get<SymbolPlacement>();
-    const SymbolPlacementType iconPlacement = layout.get<IconRotationAlignment>() != AlignmentType::Map
-                                                  ? SymbolPlacementType::Point
-                                                  : layout.get<SymbolPlacement>();
+// Analog of `addToLineVertexArray` in JS. This version doesn't need to build up a line array like the
+// JS version does, but it uses the same logic to calculate tile distances.
+std::vector<float> CalculateTileDistances(const GeometryCoordinates& line, const Anchor& anchor) {
+    std::vector<float> tileDistances(line.size());
+    if (anchor.segment != -1) {
+        auto sumForwardLength = util::dist<float>(anchor.point, line[anchor.segment + 1]);
+        auto sumBackwardLength = util::dist<float>(anchor.point, line[anchor.segment]);
+        for (size_t i = anchor.segment + 1; i < line.size(); i++) {
+            tileDistances[i] = sumForwardLength;
+            if (i < line.size() - 1) {
+                sumForwardLength += util::dist<float>(line[i + 1], line[i]);
+            }
+        }
+        for (auto i = anchor.segment; i >= 0; i--) {
+            tileDistances[i] = sumBackwardLength;
+            if (i > 0) {
+                sumBackwardLength += util::dist<float>(line[i - 1], line[i]);
+            }
+        }
+    }
+    return tileDistances;
+}
 
+std::unique_ptr<SymbolBucket> SymbolLayout::place(const bool showCollisionBoxes) {
     const bool mayOverlap = layout.get<TextAllowOverlap>() || layout.get<IconAllowOverlap>() ||
         layout.get<TextIgnorePlacement>() || layout.get<IconIgnorePlacement>();
+    
+    auto bucket = std::make_unique<SymbolBucket>(layout, layerPaintProperties, textSize, iconSize, zoom, sdfIcons, iconsNeedLinear, mayOverlap, std::move(symbolInstances));
 
-    const bool keepUpright = layout.get<TextKeepUpright>();
-
-    // Sort symbols by their y position on the canvas so that they lower symbols
-    // are drawn on top of higher symbols.
-    // Don't sort symbols that won't overlap because it isn't necessary and
-    // because it causes more labels to pop in and out when rotating.
-    if (mayOverlap) {
-        const float sin = std::sin(collisionTile.config.angle);
-        const float cos = std::cos(collisionTile.config.angle);
-
-        std::sort(symbolInstances.begin(), symbolInstances.end(), [sin, cos](SymbolInstance &a, SymbolInstance &b) {
-            const int32_t aRotated = sin * a.anchor.point.x + cos * a.anchor.point.y;
-            const int32_t bRotated = sin * b.anchor.point.x + cos * b.anchor.point.y;
-            return aRotated != bRotated ?
-                aRotated < bRotated :
-                a.index > b.index;
-        });
-    }
-
-    for (SymbolInstance &symbolInstance : symbolInstances) {
+    for (SymbolInstance &symbolInstance : bucket->symbolInstances) {
 
         const bool hasText = symbolInstance.hasText;
         const bool hasIcon = symbolInstance.hasIcon;
 
-        const bool iconWithoutText = layout.get<TextOptional>() || !hasText;
-        const bool textWithoutIcon = layout.get<IconOptional>() || !hasIcon;
-
-        // Calculate the scales at which the text and icon can be placed without collision.
-
-        float glyphScale = hasText ?
-            collisionTile.placeFeature(symbolInstance.textCollisionFeature,
-                    layout.get<TextAllowOverlap>(), layout.get<SymbolAvoidEdges>()) :
-            collisionTile.minScale;
-        float iconScale = hasIcon ?
-            collisionTile.placeFeature(symbolInstance.iconCollisionFeature,
-                    layout.get<IconAllowOverlap>(), layout.get<SymbolAvoidEdges>()) :
-            collisionTile.minScale;
-
-
-        // Combine the scales for icons and text.
-
-        if (!iconWithoutText && !textWithoutIcon) {
-            iconScale = glyphScale = util::max(iconScale, glyphScale);
-        } else if (!textWithoutIcon && glyphScale) {
-            glyphScale = util::max(iconScale, glyphScale);
-        } else if (!iconWithoutText && iconScale) {
-            iconScale = util::max(iconScale, glyphScale);
-        }
-
         const auto& feature = features.at(symbolInstance.featureIndex);
 
         // Insert final placement into collision tree and add glyphs/icons to buffers
 
         if (hasText) {
-            const float placementZoom = util::max(util::log2(glyphScale) + zoom, 0.0f);
-            collisionTile.insertFeature(symbolInstance.textCollisionFeature, glyphScale, layout.get<TextIgnorePlacement>());
-            if (glyphScale < collisionTile.maxScale) {
-
-                const float labelAngle = std::fmod((symbolInstance.anchor.angle + collisionTile.config.angle) + 2 * M_PI, 2 * M_PI);
-                const bool inVerticalRange = (
-                    (labelAngle > M_PI * 1.0 / 4.0 && labelAngle <= M_PI * 3.0 / 4) ||
-                    (labelAngle > M_PI * 5.0 / 4.0 && labelAngle <= M_PI * 7.0 / 4));
-                const bool useVerticalMode = symbolInstance.writingModes & WritingModeType::Vertical && inVerticalRange;
-
-                const Range<float> sizeData = bucket->textSizeBinder->getVertexSizeData(feature);
+            const Range<float> sizeData = bucket->textSizeBinder->getVertexSizeData(feature);
+            bucket->text.placedSymbols.emplace_back(symbolInstance.anchor.point, symbolInstance.anchor.segment, sizeData.min, sizeData.max,
+                    symbolInstance.textOffset, symbolInstance.writingModes, symbolInstance.line, CalculateTileDistances(symbolInstance.line, symbolInstance.anchor));
+            symbolInstance.placedTextIndex = bucket->text.placedSymbols.size() - 1;
+            PlacedSymbol& horizontalSymbol = bucket->text.placedSymbols.back();
+
+            bool firstHorizontal = true;
+            for (const auto& symbol : symbolInstance.horizontalGlyphQuads) {
+                size_t index = addSymbol(
+                    bucket->text, sizeData, symbol,
+                    symbolInstance.anchor, horizontalSymbol);
+                if (firstHorizontal) {
+                    horizontalSymbol.vertexStartIndex = index;
+                    firstHorizontal = false;
+                }
+            }
+            
+            if (symbolInstance.writingModes & WritingModeType::Vertical) {
                 bucket->text.placedSymbols.emplace_back(symbolInstance.anchor.point, symbolInstance.anchor.segment, sizeData.min, sizeData.max,
-                        symbolInstance.textOffset, placementZoom, useVerticalMode, symbolInstance.line);
-
-                for (const auto& symbol : symbolInstance.glyphQuads) {
-                    addSymbol(
-                        bucket->text, sizeData, symbol, placementZoom,
-                        keepUpright, textPlacement, symbolInstance.anchor, bucket->text.placedSymbols.back());
+                        symbolInstance.textOffset, WritingModeType::Vertical, symbolInstance.line, CalculateTileDistances(symbolInstance.line, symbolInstance.anchor));
+                symbolInstance.placedVerticalTextIndex = bucket->text.placedSymbols.size() - 1;
+                
+                PlacedSymbol& verticalSymbol = bucket->text.placedSymbols.back();
+                bool firstVertical = true;
+                
+                for (const auto& symbol : symbolInstance.verticalGlyphQuads) {
+                    size_t index = addSymbol(
+                        bucket->text, sizeData, symbol,
+                        symbolInstance.anchor, verticalSymbol);
+                    
+                    if (firstVertical) {
+                        verticalSymbol.vertexStartIndex = index;
+                        firstVertical = false;
+                    }
                 }
             }
         }
 
         if (hasIcon) {
-            const float placementZoom = util::max(util::log2(iconScale) + zoom, 0.0f);
-            collisionTile.insertFeature(symbolInstance.iconCollisionFeature, iconScale, layout.get<IconIgnorePlacement>());
-            if (iconScale < collisionTile.maxScale && symbolInstance.iconQuad) {
+            if (symbolInstance.iconQuad) {
                 const Range<float> sizeData = bucket->iconSizeBinder->getVertexSizeData(feature);
                 bucket->icon.placedSymbols.emplace_back(symbolInstance.anchor.point, symbolInstance.anchor.segment, sizeData.min, sizeData.max,
-                        symbolInstance.iconOffset, placementZoom, false, symbolInstance.line);
-                addSymbol(
-                    bucket->icon, sizeData, *symbolInstance.iconQuad, placementZoom,
-                    keepUpright, iconPlacement, symbolInstance.anchor, bucket->icon.placedSymbols.back());
+                        symbolInstance.iconOffset, WritingModeType::None, symbolInstance.line, std::vector<float>());
+                symbolInstance.placedIconIndex = bucket->icon.placedSymbols.size() - 1;
+                PlacedSymbol& iconSymbol = bucket->icon.placedSymbols.back();
+                iconSymbol.vertexStartIndex = addSymbol(
+                                                        bucket->icon, sizeData, *symbolInstance.iconQuad,
+                                                        symbolInstance.anchor, iconSymbol);
             }
         }
         
@@ -503,20 +490,17 @@ std::unique_ptr<SymbolBucket> SymbolLayout::place(CollisionTile& collisionTile)
         }
     }
 
-    if (collisionTile.config.debug) {
-        addToDebugBuffers(collisionTile, *bucket);
+    if (showCollisionBoxes) {
+        addToDebugBuffers(*bucket);
     }
 
     return bucket;
 }
 
 template <typename Buffer>
-void SymbolLayout::addSymbol(Buffer& buffer,
+size_t SymbolLayout::addSymbol(Buffer& buffer,
                              const Range<float> sizeData,
                              const SymbolQuad& symbol,
-                             const float placementZoom,
-                             const bool keepUpright,
-                             const style::SymbolPlacementType placement,
                              const Anchor& labelAnchor,
                              PlacedSymbol& placedSymbol) {
     constexpr const uint16_t vertexLength = 4;
@@ -527,11 +511,6 @@ void SymbolLayout::addSymbol(Buffer& buffer,
     const auto &br = symbol.br;
     const auto &tex = symbol.tex;
 
-    if (placement == style::SymbolPlacementType::Line && keepUpright) {
-        // drop incorrectly oriented glyphs
-        if ((symbol.writingMode == WritingModeType::Vertical) != placedSymbol.useVerticalMode) return;
-    }
-
     if (buffer.segments.empty() || buffer.segments.back().vertexLength + vertexLength > std::numeric_limits<uint16_t>::max()) {
         buffer.segments.emplace_back(buffer.vertices.vertexSize(), buffer.triangles.indexSize());
     }
@@ -548,11 +527,19 @@ void SymbolLayout::addSymbol(Buffer& buffer,
     buffer.vertices.emplace_back(SymbolLayoutAttributes::vertex(labelAnchor.point, bl, symbol.glyphOffset.y, tex.x, tex.y + tex.h, sizeData));
     buffer.vertices.emplace_back(SymbolLayoutAttributes::vertex(labelAnchor.point, br, symbol.glyphOffset.y, tex.x + tex.w, tex.y + tex.h, sizeData));
     
-    auto dynamicVertex = SymbolDynamicLayoutAttributes::vertex(labelAnchor.point, 0, placementZoom);
+    // Dynamic/Opacity vertices are initialized so that the vertex count always agrees with
+    // the layout vertex buffer, but they will always be updated before rendering happens
+    auto dynamicVertex = SymbolDynamicLayoutAttributes::vertex(labelAnchor.point, 0);
     buffer.dynamicVertices.emplace_back(dynamicVertex);
     buffer.dynamicVertices.emplace_back(dynamicVertex);
     buffer.dynamicVertices.emplace_back(dynamicVertex);
     buffer.dynamicVertices.emplace_back(dynamicVertex);
+    
+    auto opacityVertex = SymbolOpacityAttributes::vertex(1.0, 1.0);
+    buffer.opacityVertices.emplace_back(opacityVertex);
+    buffer.opacityVertices.emplace_back(opacityVertex);
+    buffer.opacityVertices.emplace_back(opacityVertex);
+    buffer.opacityVertices.emplace_back(opacityVertex);
 
     // add the two triangles, referencing the four coordinates we just inserted.
     buffer.triangles.emplace_back(index + 0, index + 1, index + 2);
@@ -562,54 +549,62 @@ void SymbolLayout::addSymbol(Buffer& buffer,
     segment.indexLength += 6;
 
     placedSymbol.glyphOffsets.push_back(symbol.glyphOffset.x);
+    
+    return index;
 }
 
-void SymbolLayout::addToDebugBuffers(CollisionTile& collisionTile, SymbolBucket& bucket) {
+void SymbolLayout::addToDebugBuffers(SymbolBucket& bucket) {
 
     if (!hasSymbolInstances()) {
         return;
     }
 
-    const float yStretch = collisionTile.yStretch;
-
-    auto& collisionBox = bucket.collisionBox;
-
     for (const SymbolInstance &symbolInstance : symbolInstances) {
         auto populateCollisionBox = [&](const auto& feature) {
+            SymbolBucket::CollisionBuffer& collisionBuffer = feature.alongLine ?
+                static_cast<SymbolBucket::CollisionBuffer&>(bucket.collisionCircle) :
+                static_cast<SymbolBucket::CollisionBuffer&>(bucket.collisionBox);
             for (const CollisionBox &box : feature.boxes) {
                 auto& anchor = box.anchor;
 
-                Point<float> tl{box.x1, box.y1 * yStretch};
-                Point<float> tr{box.x2, box.y1 * yStretch};
-                Point<float> bl{box.x1, box.y2 * yStretch};
-                Point<float> br{box.x2, box.y2 * yStretch};
-                tl = util::matrixMultiply(collisionTile.reverseRotationMatrix, tl);
-                tr = util::matrixMultiply(collisionTile.reverseRotationMatrix, tr);
-                bl = util::matrixMultiply(collisionTile.reverseRotationMatrix, bl);
-                br = util::matrixMultiply(collisionTile.reverseRotationMatrix, br);
-
-                const float maxZoom = util::clamp(zoom + util::log2(box.maxScale), util::MIN_ZOOM_F, util::MAX_ZOOM_F);
-                const float placementZoom = util::clamp(zoom + util::log2(box.placementScale), util::MIN_ZOOM_F, util::MAX_ZOOM_F);
+                Point<float> tl{box.x1, box.y1};
+                Point<float> tr{box.x2, box.y1};
+                Point<float> bl{box.x1, box.y2};
+                Point<float> br{box.x2, box.y2};
 
                 static constexpr std::size_t vertexLength = 4;
-                static constexpr std::size_t indexLength = 8;
+                const std::size_t indexLength = feature.alongLine ? 6 : 8;
 
-                if (collisionBox.segments.empty() || collisionBox.segments.back().vertexLength + vertexLength > std::numeric_limits<uint16_t>::max()) {
-                    collisionBox.segments.emplace_back(collisionBox.vertices.vertexSize(), collisionBox.lines.indexSize());
+                if (collisionBuffer.segments.empty() || collisionBuffer.segments.back().vertexLength + vertexLength > std::numeric_limits<uint16_t>::max()) {
+                    collisionBuffer.segments.emplace_back(collisionBuffer.vertices.vertexSize(),
+                      feature.alongLine? bucket.collisionCircle.triangles.indexSize() : bucket.collisionBox.lines.indexSize());
                 }
 
-                auto& segment = collisionBox.segments.back();
+                auto& segment = collisionBuffer.segments.back();
                 uint16_t index = segment.vertexLength;
 
-                collisionBox.vertices.emplace_back(CollisionBoxProgram::vertex(anchor, symbolInstance.anchor.point, tl, maxZoom, placementZoom));
-                collisionBox.vertices.emplace_back(CollisionBoxProgram::vertex(anchor, symbolInstance.anchor.point, tr, maxZoom, placementZoom));
-                collisionBox.vertices.emplace_back(CollisionBoxProgram::vertex(anchor, symbolInstance.anchor.point, br, maxZoom, placementZoom));
-                collisionBox.vertices.emplace_back(CollisionBoxProgram::vertex(anchor, symbolInstance.anchor.point, bl, maxZoom, placementZoom));
-
-                collisionBox.lines.emplace_back(index + 0, index + 1);
-                collisionBox.lines.emplace_back(index + 1, index + 2);
-                collisionBox.lines.emplace_back(index + 2, index + 3);
-                collisionBox.lines.emplace_back(index + 3, index + 0);
+                collisionBuffer.vertices.emplace_back(CollisionBoxProgram::vertex(anchor, symbolInstance.anchor.point, tl));
+                collisionBuffer.vertices.emplace_back(CollisionBoxProgram::vertex(anchor, symbolInstance.anchor.point, tr));
+                collisionBuffer.vertices.emplace_back(CollisionBoxProgram::vertex(anchor, symbolInstance.anchor.point, br));
+                collisionBuffer.vertices.emplace_back(CollisionBoxProgram::vertex(anchor, symbolInstance.anchor.point, bl));
+
+                // Dynamic vertices are initialized so that the vertex count always agrees with
+                // the layout vertex buffer, but they will always be updated before rendering happens
+                auto dynamicVertex = CollisionBoxDynamicAttributes::vertex(false, false);
+                collisionBuffer.dynamicVertices.emplace_back(dynamicVertex);
+                collisionBuffer.dynamicVertices.emplace_back(dynamicVertex);
+                collisionBuffer.dynamicVertices.emplace_back(dynamicVertex);
+                collisionBuffer.dynamicVertices.emplace_back(dynamicVertex);
+
+                if (feature.alongLine) {
+                    bucket.collisionCircle.triangles.emplace_back(index, index + 1, index + 2);
+                    bucket.collisionCircle.triangles.emplace_back(index, index + 2, index + 3);
+                } else {
+                    bucket.collisionBox.lines.emplace_back(index + 0, index + 1);
+                    bucket.collisionBox.lines.emplace_back(index + 1, index + 2);
+                    bucket.collisionBox.lines.emplace_back(index + 2, index + 3);
+                    bucket.collisionBox.lines.emplace_back(index + 3, index + 0);
+                }
 
                 segment.vertexLength += vertexLength;
                 segment.indexLength += indexLength;
diff --git a/src/mbgl/layout/symbol_layout.hpp b/src/mbgl/layout/symbol_layout.hpp
index 90f5b3c91d..6951c29ada 100644
--- a/src/mbgl/layout/symbol_layout.hpp
+++ b/src/mbgl/layout/symbol_layout.hpp
@@ -16,7 +16,6 @@
 namespace mbgl {
 
 class BucketParameters;
-class CollisionTile;
 class SymbolBucket;
 class Anchor;
 class RenderLayer;
@@ -35,42 +34,44 @@ public:
                  GlyphDependencies&);
 
     void prepare(const GlyphMap&, const GlyphPositions&,
-                 const ImageMap&, const ImagePositions&);
+                 const ImageMap&, const ImagePositions&,
+                 const OverscaledTileID&, const std::string&);
 
-    std::unique_ptr<SymbolBucket> place(CollisionTile&);
+    std::unique_ptr<SymbolBucket> place(const bool showCollisionBoxes);
 
     bool hasSymbolInstances() const;
 
     std::map<std::string,
         std::pair<style::IconPaintProperties::PossiblyEvaluated, style::TextPaintProperties::PossiblyEvaluated>> layerPaintProperties;
 
+    const std::string bucketName;
+    std::vector<SymbolInstance> symbolInstances;
+
 private:
     void addFeature(const size_t,
                     const SymbolFeature&,
                     const std::pair<Shaping, Shaping>& shapedTextOrientations,
                     optional<PositionedIcon> shapedIcon,
-                    const GlyphPositionMap&);
+                    const GlyphPositionMap&,
+                    const OverscaledTileID&,
+                    const std::string&);
 
     bool anchorIsTooClose(const std::u16string& text, const float repeatDistance, const Anchor&);
     std::map<std::u16string, std::vector<Anchor>> compareText;
 
-    void addToDebugBuffers(CollisionTile&, SymbolBucket&);
+    void addToDebugBuffers(SymbolBucket&);
 
     // Adds placed items to the buffer.
     template <typename Buffer>
-    void addSymbol(Buffer&,
+    size_t addSymbol(Buffer&,
                    const Range<float> sizeData,
                    const SymbolQuad&,
-                   float scale,
-                   const bool keepUpright,
-                   const style::SymbolPlacementType,
                    const Anchor& labelAnchor,
                    PlacedSymbol& placedSymbol);
 
     // Stores the layer so that we can hold on to GeometryTileFeature instances in SymbolFeature,
     // which may reference data from this object.
     const std::unique_ptr<GeometryTileLayer> sourceLayer;
-    const std::string bucketName;
     const float overscaling;
     const float zoom;
     const MapMode mode;
@@ -87,7 +88,6 @@ private:
     style::TextSize::UnevaluatedType textSize;
     style::IconSize::UnevaluatedType iconSize;
 
-    std::vector<SymbolInstance> symbolInstances;
     std::vector<SymbolFeature> features;
 
     BiDi bidi; // Consider moving this up to geometry tile worker to reduce reinstantiation costs; use of BiDi/ubiditransform object must be constrained to one thread
diff --git a/src/mbgl/layout/symbol_projection.cpp b/src/mbgl/layout/symbol_projection.cpp
index 279d251f8f..b8c399d857 100644
--- a/src/mbgl/layout/symbol_projection.cpp
+++ b/src/mbgl/layout/symbol_projection.cpp
@@ -3,7 +3,6 @@
 #include <mbgl/renderer/render_tile.hpp>
 #include <mbgl/renderer/buckets/symbol_bucket.hpp>
 #include <mbgl/renderer/layers/render_symbol_layer.hpp>
-#include <mbgl/renderer/frame_history.hpp>
 #include <mbgl/util/optional.hpp>
 #include <mbgl/util/math.hpp>
 
@@ -93,9 +92,6 @@ namespace mbgl {
         return m;
     }
 
-
-    typedef std::pair<Point<float>,float> PointAndCameraDistance;
-
     PointAndCameraDistance project(const Point<float>& point, const mat4& matrix) {
         vec4 pos = {{ point.x, point.y, 0, 1 }};
         matrix::transformMat4(pos, pos, matrix);
@@ -114,7 +110,7 @@ namespace mbgl {
         }
     }
 
-    bool isVisible(const vec4& anchorPos, const float placementZoom, const std::array<double, 2>& clippingBuffer, const FrameHistory& frameHistory) {
+    bool isVisible(const vec4& anchorPos, const std::array<double, 2>& clippingBuffer) {
         const float x = anchorPos[0] / anchorPos[3];
         const float y = anchorPos[1] / anchorPos[3];
         const bool inPaddedViewport = (
@@ -122,12 +118,12 @@ namespace mbgl {
                 x <= clippingBuffer[0] &&
                 y >= -clippingBuffer[1] &&
                 y <= clippingBuffer[1]);
-        return inPaddedViewport && frameHistory.isVisible(placementZoom);
+        return inPaddedViewport;
     }
 
-    void addDynamicAttributes(const Point<float>& anchorPoint, const float angle, const float placementZoom,
+    void addDynamicAttributes(const Point<float>& anchorPoint, const float angle,
             gl::VertexVector<SymbolDynamicLayoutAttributes::Vertex>& dynamicVertexArray) {
-        auto dynamicVertex = SymbolDynamicLayoutAttributes::vertex(anchorPoint, angle, placementZoom);
+        auto dynamicVertex = SymbolDynamicLayoutAttributes::vertex(anchorPoint, angle);
         dynamicVertexArray.emplace_back(dynamicVertex);
         dynamicVertexArray.emplace_back(dynamicVertex);
         dynamicVertexArray.emplace_back(dynamicVertex);
@@ -137,20 +133,15 @@ namespace mbgl {
     void hideGlyphs(size_t numGlyphs, gl::VertexVector<SymbolDynamicLayoutAttributes::Vertex>& dynamicVertexArray) {
         const Point<float> offscreenPoint = { -INFINITY, -INFINITY };
         for (size_t i = 0; i < numGlyphs; i++) {
-            addDynamicAttributes(offscreenPoint, 0, 25, dynamicVertexArray);
+            addDynamicAttributes(offscreenPoint, 0, dynamicVertexArray);
         }
     }
 
-    struct PlacedGlyph {
-        PlacedGlyph(Point<float> point_, float angle_) : point(point_), angle(angle_) {}
-        Point<float> point;
-        float angle;
-    };
-    
     enum PlacementResult {
         OK,
         NotEnoughRoom,
-        NeedsFlipping
+        NeedsFlipping,
+        UseVertical
     };
     
     Point<float> projectTruncatedLineSegment(const Point<float>& previousTilePoint, const Point<float>& currentTilePoint, const Point<float>& previousProjectedPoint, const float minimumLength, const mat4& projectionMatrix) {
@@ -165,7 +156,7 @@ namespace mbgl {
     }
 
 	optional<PlacedGlyph> placeGlyphAlongLine(const float offsetX, const float lineOffsetX, const float lineOffsetY, const bool flip,
-            const Point<float>& projectedAnchorPoint, const Point<float>& tileAnchorPoint, const uint16_t anchorSegment, const GeometryCoordinates& line, const mat4& labelPlaneMatrix) {
+            const Point<float>& projectedAnchorPoint, const Point<float>& tileAnchorPoint, const uint16_t anchorSegment, const GeometryCoordinates& line, const std::vector<float>& tileDistances, const mat4& labelPlaneMatrix, const bool returnTileDistance) {
 
         const float combinedOffsetX = flip ?
             offsetX - lineOffsetX :
@@ -185,6 +176,7 @@ namespace mbgl {
 
         int32_t currentIndex = dir > 0 ? anchorSegment : anchorSegment + 1;
 
+        const int32_t initialIndex = currentIndex;
         Point<float> current = projectedAnchorPoint;
         Point<float> prev = projectedAnchorPoint;
         float distanceToPrev = 0.0;
@@ -195,7 +187,9 @@ namespace mbgl {
             currentIndex += dir;
 
             // offset does not fit on the projected line
-            if (currentIndex < 0 || currentIndex >= static_cast<int32_t>(line.size())) return {};
+            if (currentIndex < 0 || currentIndex >= static_cast<int32_t>(line.size())) {
+                return {};
+            }
 
             prev = current;
             PointAndCameraDistance projection = project(convertPoint<float>(line.at(currentIndex)), labelPlaneMatrix);
@@ -225,7 +219,62 @@ namespace mbgl {
 
         const float segmentAngle = angle + std::atan2(current.y - prev.y, current.x - prev.x);
 
-        return {{ p, segmentAngle }};
+        return {{
+            p,
+            segmentAngle,
+            returnTileDistance ?
+                TileDistance(
+                    (currentIndex - dir) == initialIndex ? 0 : tileDistances[currentIndex - dir],
+                    absOffsetX - distanceToPrev
+                ) :
+                optional<TileDistance>()
+        }};
+    }
+    
+    optional<std::pair<PlacedGlyph, PlacedGlyph>> placeFirstAndLastGlyph(const float fontScale,
+                                                            const float lineOffsetX,
+                                                            const float lineOffsetY,
+                                                            const bool flip,
+                                                            const Point<float>& anchorPoint,
+                                                            const Point<float>& tileAnchorPoint,
+                                                            const PlacedSymbol& symbol,
+                                                            const mat4& labelPlaneMatrix,
+                                                            const bool returnTileDistance) {
+
+        const float firstGlyphOffset = symbol.glyphOffsets.front();
+        const float lastGlyphOffset = symbol.glyphOffsets.back();;
+
+        optional<PlacedGlyph> firstPlacedGlyph = placeGlyphAlongLine(fontScale * firstGlyphOffset, lineOffsetX, lineOffsetY, flip, anchorPoint, tileAnchorPoint, symbol.segment, symbol.line, symbol.tileDistances, labelPlaneMatrix,  returnTileDistance);
+        if (!firstPlacedGlyph)
+            return optional<std::pair<PlacedGlyph, PlacedGlyph>>();
+
+        optional<PlacedGlyph> lastPlacedGlyph = placeGlyphAlongLine(fontScale * lastGlyphOffset, lineOffsetX, lineOffsetY, flip, anchorPoint, tileAnchorPoint, symbol.segment, symbol.line, symbol.tileDistances, labelPlaneMatrix, returnTileDistance);
+        if (!lastPlacedGlyph)
+            return optional<std::pair<PlacedGlyph, PlacedGlyph>>();
+
+        return std::make_pair(*firstPlacedGlyph, *lastPlacedGlyph);
+    }
+    
+    optional<PlacementResult> requiresOrientationChange(const WritingModeType writingModes, const Point<float>& firstPoint,  const Point<float>& lastPoint, const float aspectRatio) {
+        if (writingModes == (WritingModeType::Horizontal | WritingModeType::Vertical)) {
+            // On top of choosing whether to flip, choose whether to render this version of the glyphs or the alternate
+            // vertical glyphs. We can't just filter out vertical glyphs in the horizontal range because the horizontal
+            // and vertical versions can have slightly different projections which could lead to angles where both or
+            // neither showed.
+            auto rise = std::abs(lastPoint.y - firstPoint.y);
+            auto run = std::abs(lastPoint.x - firstPoint.x) * aspectRatio;
+            if (rise > run) {
+                return PlacementResult::UseVertical;
+            }
+        }
+
+        if ((writingModes == WritingModeType::Vertical) ?
+            (firstPoint.y < lastPoint.y) :
+            (firstPoint.x > lastPoint.x)) {
+            // Includes "horizontalOnly" case for labels without vertical glyphs
+            return PlacementResult::NeedsFlipping;
+        }
+        return {};
     }
 
     PlacementResult placeGlyphsAlongLine(const PlacedSymbol& symbol,
@@ -236,7 +285,8 @@ namespace mbgl {
                               const mat4& labelPlaneMatrix,
                               const mat4& glCoordMatrix,
                               gl::VertexVector<SymbolDynamicLayoutAttributes::Vertex>& dynamicVertexArray,
-                              const Point<float>& projectedAnchorPoint) {
+                              const Point<float>& projectedAnchorPoint,
+                              const float aspectRatio) {
         const float fontScale = fontSize / 24.0;
         const float lineOffsetX = symbol.lineOffset[0] * fontSize;
         const float lineOffsetY = symbol.lineOffset[1] * fontSize;
@@ -244,33 +294,30 @@ namespace mbgl {
         std::vector<PlacedGlyph> placedGlyphs;
         if (symbol.glyphOffsets.size() > 1) {
 
-            const float firstGlyphOffset = symbol.glyphOffsets.front();
-            const float lastGlyphOffset = symbol.glyphOffsets.back();
-            
-            optional<PlacedGlyph> firstPlacedGlyph = placeGlyphAlongLine(fontScale * firstGlyphOffset, lineOffsetX, lineOffsetY, flip, projectedAnchorPoint, symbol.anchorPoint, symbol.segment, symbol.line, labelPlaneMatrix);
-            if (!firstPlacedGlyph)
-                return PlacementResult::NotEnoughRoom;
-
-            optional<PlacedGlyph> lastPlacedGlyph = placeGlyphAlongLine(fontScale * lastGlyphOffset, lineOffsetX, lineOffsetY, flip, projectedAnchorPoint, symbol.anchorPoint, symbol.segment, symbol.line, labelPlaneMatrix);
-            if (!lastPlacedGlyph)
+            const optional<std::pair<PlacedGlyph,PlacedGlyph>> firstAndLastGlyph =
+                placeFirstAndLastGlyph(fontScale, lineOffsetX, lineOffsetY, flip, projectedAnchorPoint, symbol.anchorPoint, symbol, labelPlaneMatrix, false);
+            if (!firstAndLastGlyph) {
                 return PlacementResult::NotEnoughRoom;
+            }
 
-            const Point<float> firstPoint = project(firstPlacedGlyph->point, glCoordMatrix).first;
-            const Point<float> lastPoint = project(lastPlacedGlyph->point, glCoordMatrix).first;
+            const Point<float> firstPoint = project(firstAndLastGlyph->first.point, glCoordMatrix).first;
+            const Point<float> lastPoint = project(firstAndLastGlyph->second.point, glCoordMatrix).first;
 
-            if (keepUpright && !flip &&
-                (symbol.useVerticalMode ? firstPoint.y < lastPoint.y : firstPoint.x > lastPoint.x)) {
-                return PlacementResult::NeedsFlipping;
+            if (keepUpright && !flip) {
+                auto orientationChange = requiresOrientationChange(symbol.writingModes, firstPoint, lastPoint, aspectRatio);
+                if (orientationChange) {
+                    return *orientationChange;
+                }
             }
 
-            placedGlyphs.push_back(*firstPlacedGlyph);
+            placedGlyphs.push_back(firstAndLastGlyph->first);
             for (size_t glyphIndex = 1; glyphIndex < symbol.glyphOffsets.size() - 1; glyphIndex++) {
                 const float glyphOffsetX = symbol.glyphOffsets[glyphIndex];
                 // Since first and last glyph fit on the line, we're sure that the rest of the glyphs can be placed
-                auto placedGlyph = placeGlyphAlongLine(glyphOffsetX * fontScale, lineOffsetX, lineOffsetY, flip, projectedAnchorPoint, symbol.anchorPoint, symbol.segment, symbol.line, labelPlaneMatrix);
+                auto placedGlyph = placeGlyphAlongLine(glyphOffsetX * fontScale, lineOffsetX, lineOffsetY, flip, projectedAnchorPoint, symbol.anchorPoint, symbol.segment, symbol.line, symbol.tileDistances, labelPlaneMatrix, false);
                 placedGlyphs.push_back(*placedGlyph);
             }
-            placedGlyphs.push_back(*lastPlacedGlyph);
+            placedGlyphs.push_back(firstAndLastGlyph->second);
         } else {
             // Only a single glyph to place
             // So, determine whether to flip based on projected angle of the line segment it's on
@@ -285,14 +332,15 @@ namespace mbgl {
                     projectedVertex.first :
                     projectTruncatedLineSegment(symbol.anchorPoint,tileSegmentEnd, a, 1, posMatrix);
                 
-                if (symbol.useVerticalMode ? b.y > a.y : b.x < a.x) {
-                    return PlacementResult::NeedsFlipping;
+                auto orientationChange = requiresOrientationChange(symbol.writingModes, a, b, aspectRatio);
+                if (orientationChange) {
+                    return *orientationChange;
                 }
             }
             assert(symbol.glyphOffsets.size() == 1); // We are relying on SymbolInstance.hasText filtering out symbols without any glyphs at all
             const float glyphOffsetX = symbol.glyphOffsets.front();
             optional<PlacedGlyph> singleGlyph = placeGlyphAlongLine(fontScale * glyphOffsetX, lineOffsetX, lineOffsetY, flip, projectedAnchorPoint, symbol.anchorPoint, symbol.segment,
-                symbol.line, labelPlaneMatrix);
+                symbol.line, symbol.tileDistances, labelPlaneMatrix, false);
             if (!singleGlyph)
                 return PlacementResult::NotEnoughRoom;
 
@@ -300,7 +348,7 @@ namespace mbgl {
         }
 
         for (auto& placedGlyph : placedGlyphs) {
-            addDynamicAttributes(placedGlyph.point, placedGlyph.angle, symbol.placementZoom, dynamicVertexArray);
+            addDynamicAttributes(placedGlyph.point, placedGlyph.angle, dynamicVertexArray);
         }
         
         return PlacementResult::OK;
@@ -309,7 +357,7 @@ namespace mbgl {
 
     void reprojectLineLabels(gl::VertexVector<SymbolDynamicLayoutAttributes::Vertex>& dynamicVertexArray, const std::vector<PlacedSymbol>& placedSymbols,
 			const mat4& posMatrix, const style::SymbolPropertyValues& values,
-            const RenderTile& tile, const SymbolSizeBinder& sizeBinder, const TransformState& state, const FrameHistory& frameHistory) {
+            const RenderTile& tile, const SymbolSizeBinder& sizeBinder, const TransformState& state) {
 
         const ZoomEvaluatedSize partiallyEvaluatedSize = sizeBinder.evaluateForZoom(state.getZoom());
 
@@ -325,19 +373,31 @@ namespace mbgl {
         const mat4 glCoordMatrix = getGlCoordMatrix(posMatrix, pitchWithMap, rotateWithMap, state, pixelsToTileUnits);
         
         dynamicVertexArray.clear();
+        
+        bool useVertical = false;
 
         for (auto& placedSymbol : placedSymbols) {
+            // Don't do calculations for vertical glyphs unless the previous symbol was horizontal
+            // and we determined that vertical glyphs were necessary.
+            // Also don't do calculations for symbols that are collided and fully faded out
+            if (placedSymbol.hidden || (placedSymbol.writingModes == WritingModeType::Vertical && !useVertical)) {
+                hideGlyphs(placedSymbol.glyphOffsets.size(), dynamicVertexArray);
+                continue;
+            }
+            // Awkward... but we're counting on the paired "vertical" symbol coming immediately after its horizontal counterpart
+            useVertical = false;
+            
 			vec4 anchorPos = {{ placedSymbol.anchorPoint.x, placedSymbol.anchorPoint.y, 0, 1 }};
             matrix::transformMat4(anchorPos, anchorPos, posMatrix);
 
             // Don't bother calculating the correct point for invisible labels.
-            if (!isVisible(anchorPos, placedSymbol.placementZoom, clippingBuffer, frameHistory)) {
+            if (!isVisible(anchorPos, clippingBuffer)) {
                 hideGlyphs(placedSymbol.glyphOffsets.size(), dynamicVertexArray);
                 continue;
             }
 
             const float cameraToAnchorDistance = anchorPos[3];
-            const float perspectiveRatio = 1 + 0.5 * ((cameraToAnchorDistance / state.getCameraToCenterDistance()) - 1.0);
+            const float perspectiveRatio = 0.5 + 0.5 * (cameraToAnchorDistance / state.getCameraToCenterDistance());
 
             const float fontSize = evaluateSizeForFeature(partiallyEvaluatedSize, placedSymbol);
             const float pitchScaledFontSize = values.pitchAlignment == style::AlignmentType::Map ?
@@ -346,11 +406,13 @@ namespace mbgl {
             
             const Point<float> anchorPoint = project(placedSymbol.anchorPoint, labelPlaneMatrix).first;
 
-            PlacementResult placeUnflipped = placeGlyphsAlongLine(placedSymbol, pitchScaledFontSize, false /*unflipped*/, values.keepUpright, posMatrix, labelPlaneMatrix, glCoordMatrix, dynamicVertexArray, anchorPoint);
+            PlacementResult placeUnflipped = placeGlyphsAlongLine(placedSymbol, pitchScaledFontSize, false /*unflipped*/, values.keepUpright, posMatrix, labelPlaneMatrix, glCoordMatrix, dynamicVertexArray, anchorPoint, state.getSize().aspectRatio());
+            
+            useVertical = placeUnflipped == PlacementResult::UseVertical;
 
-            if (placeUnflipped == PlacementResult::NotEnoughRoom ||
+            if (placeUnflipped == PlacementResult::NotEnoughRoom || useVertical ||
                 (placeUnflipped == PlacementResult::NeedsFlipping &&
-                 placeGlyphsAlongLine(placedSymbol, pitchScaledFontSize, true /*flipped*/, values.keepUpright, posMatrix, labelPlaneMatrix, glCoordMatrix, dynamicVertexArray, anchorPoint) == PlacementResult::NotEnoughRoom)) {
+                 placeGlyphsAlongLine(placedSymbol, pitchScaledFontSize, true /*flipped*/, values.keepUpright, posMatrix, labelPlaneMatrix, glCoordMatrix, dynamicVertexArray, anchorPoint, state.getSize().aspectRatio()) == PlacementResult::NotEnoughRoom)) {
                 hideGlyphs(placedSymbol.glyphOffsets.size(), dynamicVertexArray);
             }
         }
diff --git a/src/mbgl/layout/symbol_projection.hpp b/src/mbgl/layout/symbol_projection.hpp
index 2652fe7ace..8535014f22 100644
--- a/src/mbgl/layout/symbol_projection.hpp
+++ b/src/mbgl/layout/symbol_projection.hpp
@@ -8,18 +8,48 @@ namespace mbgl {
 
     class TransformState;
     class RenderTile;
-    class FrameHistory;
     class SymbolSizeBinder;
     class PlacedSymbol;
     namespace style {
         class SymbolPropertyValues;
     } // end namespace style
+    
+    struct TileDistance {
+        TileDistance(float prevTileDistance_, float lastSegmentViewportDistance_)
+            : prevTileDistance(prevTileDistance_), lastSegmentViewportDistance(lastSegmentViewportDistance_)
+        {}
+        float prevTileDistance;
+        float lastSegmentViewportDistance;
+    };
+    
+    struct PlacedGlyph {
+        PlacedGlyph(Point<float> point_, float angle_, optional<TileDistance> tileDistance_)
+            : point(point_), angle(angle_), tileDistance(std::move(tileDistance_))
+        {}
+        Point<float> point;
+        float angle;
+        optional<TileDistance> tileDistance;
+    };
 
+    float evaluateSizeForFeature(const ZoomEvaluatedSize& zoomEvaluatedSize, const PlacedSymbol& placedSymbol);
     mat4 getLabelPlaneMatrix(const mat4& posMatrix, const bool pitchWithMap, const bool rotateWithMap, const TransformState& state, const float pixelsToTileUnits);
     mat4 getGlCoordMatrix(const mat4& posMatrix, const bool pitchWithMap, const bool rotateWithMap, const TransformState& state, const float pixelsToTileUnits);
+    
+    using PointAndCameraDistance = std::pair<Point<float>,float>;
+    PointAndCameraDistance project(const Point<float>& point, const mat4& matrix);
 
     void reprojectLineLabels(gl::VertexVector<SymbolDynamicLayoutAttributes::Vertex>&, const std::vector<PlacedSymbol>&,
             const mat4& posMatrix, const style::SymbolPropertyValues&,
-            const RenderTile&, const SymbolSizeBinder& sizeBinder, const TransformState&, const FrameHistory& frameHistory);
+            const RenderTile&, const SymbolSizeBinder& sizeBinder, const TransformState&);
+    
+    optional<std::pair<PlacedGlyph, PlacedGlyph>> placeFirstAndLastGlyph(const float fontScale,
+                                                            const float lineOffsetX,
+                                                            const float lineOffsetY,
+                                                            const bool flip,
+                                                            const Point<float>& anchorPoint,
+                                                            const Point<float>& tileAnchorPoint,
+                                                            const PlacedSymbol& symbol,
+                                                            const mat4& labelPlaneMatrix,
+                                                            const bool returnTileDistance);
 
 } // end namespace mbgl
diff --git a/src/mbgl/renderer/buckets/symbol_bucket.cpp b/src/mbgl/renderer/buckets/symbol_bucket.cpp
index a3f71f1f6e..ebcf93f2b1 100644
--- a/src/mbgl/renderer/buckets/symbol_bucket.cpp
+++ b/src/mbgl/renderer/buckets/symbol_bucket.cpp
@@ -16,10 +16,14 @@ SymbolBucket::SymbolBucket(style::SymbolLayoutProperties::PossiblyEvaluated layo
                            const style::DataDrivenPropertyValue<float>& iconSize,
                            float zoom,
                            bool sdfIcons_,
-                           bool iconsNeedLinear_)
+                           bool iconsNeedLinear_,
+                           bool sortFeaturesByY_,
+                           const std::vector<SymbolInstance>&& symbolInstances_)
     : layout(std::move(layout_)),
       sdfIcons(sdfIcons_),
       iconsNeedLinear(iconsNeedLinear_ || iconSize.isDataDriven() || !iconSize.isZoomConstant()),
+      sortFeaturesByY(sortFeaturesByY_),
+      symbolInstances(std::move(symbolInstances_)),
       textSizeBinder(SymbolSizeBinder::create(zoom, textSize, TextSize::defaultValue())),
       iconSizeBinder(SymbolSizeBinder::create(zoom, iconSize, IconSize::defaultValue())) {
     
@@ -36,28 +40,84 @@ SymbolBucket::SymbolBucket(style::SymbolLayoutProperties::PossiblyEvaluated layo
 
 void SymbolBucket::upload(gl::Context& context) {
     if (hasTextData()) {
-        text.vertexBuffer = context.createVertexBuffer(std::move(text.vertices));
-        text.dynamicVertexBuffer = context.createVertexBuffer(std::move(text.dynamicVertices), gl::BufferUsage::StreamDraw);
-        text.indexBuffer = context.createIndexBuffer(std::move(text.triangles));
+        if (!staticUploaded) {
+            text.indexBuffer = context.createIndexBuffer(std::move(text.triangles), sortFeaturesByY ? gl::BufferUsage::StreamDraw : gl::BufferUsage::StaticDraw);
+            text.vertexBuffer = context.createVertexBuffer(std::move(text.vertices));
+        } else if (!sortUploaded) {
+            context.updateIndexBuffer(*text.indexBuffer, std::move(text.triangles));
+        }
+        
+        if (!dynamicUploaded) {
+            text.dynamicVertexBuffer = context.createVertexBuffer(std::move(text.dynamicVertices), gl::BufferUsage::StreamDraw);
+        }
+        if (!placementChangesUploaded) {
+            if (!text.opacityVertexBuffer) {
+                text.opacityVertexBuffer = context.createVertexBuffer(std::move(text.opacityVertices), gl::BufferUsage::StreamDraw);
+            } else {
+                context.updateVertexBuffer(*text.opacityVertexBuffer, std::move(text.opacityVertices));
+            }
+        }
     }
 
     if (hasIconData()) {
-        icon.vertexBuffer = context.createVertexBuffer(std::move(icon.vertices));
-        icon.dynamicVertexBuffer = context.createVertexBuffer(std::move(icon.dynamicVertices), gl::BufferUsage::StreamDraw);
-        icon.indexBuffer = context.createIndexBuffer(std::move(icon.triangles));
+        if (!staticUploaded) {
+            icon.indexBuffer = context.createIndexBuffer(std::move(icon.triangles), sortFeaturesByY ? gl::BufferUsage::StreamDraw : gl::BufferUsage::StaticDraw);
+            icon.vertexBuffer = context.createVertexBuffer(std::move(icon.vertices));
+        } else if (!sortUploaded) {
+            context.updateIndexBuffer(*icon.indexBuffer, std::move(icon.triangles));
+        }
+        if (!dynamicUploaded) {
+            icon.dynamicVertexBuffer = context.createVertexBuffer(std::move(icon.dynamicVertices), gl::BufferUsage::StreamDraw);
+        }
+        if (!placementChangesUploaded) {
+            if (!icon.opacityVertexBuffer) {
+                icon.opacityVertexBuffer = context.createVertexBuffer(std::move(icon.opacityVertices), gl::BufferUsage::StreamDraw);
+            } else {
+                context.updateVertexBuffer(*icon.opacityVertexBuffer, std::move(icon.opacityVertices));
+            }
+        }
     }
 
-    if (!collisionBox.vertices.empty()) {
-        collisionBox.vertexBuffer = context.createVertexBuffer(std::move(collisionBox.vertices));
-        collisionBox.indexBuffer = context.createIndexBuffer(std::move(collisionBox.lines));
+    if (hasCollisionBoxData()) {
+        if (!staticUploaded) {
+            collisionBox.indexBuffer = context.createIndexBuffer(std::move(collisionBox.lines));
+            collisionBox.vertexBuffer = context.createVertexBuffer(std::move(collisionBox.vertices));
+        }
+        if (!placementChangesUploaded) {
+            if (!collisionBox.dynamicVertexBuffer) {
+                collisionBox.dynamicVertexBuffer = context.createVertexBuffer(std::move(collisionBox.dynamicVertices), gl::BufferUsage::StreamDraw);
+            } else {
+                context.updateVertexBuffer(*collisionBox.dynamicVertexBuffer, std::move(collisionBox.dynamicVertices));
+            }
+        }
     }
-
-    for (auto& pair : paintPropertyBinders) {
-        pair.second.first.upload(context);
-        pair.second.second.upload(context);
+    
+    if (hasCollisionCircleData()) {
+        if (!staticUploaded) {
+            collisionCircle.indexBuffer = context.createIndexBuffer(std::move(collisionCircle.triangles));
+            collisionCircle.vertexBuffer = context.createVertexBuffer(std::move(collisionCircle.vertices));
+        }
+        if (!placementChangesUploaded) {
+            if (!collisionCircle.dynamicVertexBuffer) {
+                collisionCircle.dynamicVertexBuffer = context.createVertexBuffer(std::move(collisionCircle.dynamicVertices), gl::BufferUsage::StreamDraw);
+            } else {
+                context.updateVertexBuffer(*collisionCircle.dynamicVertexBuffer, std::move(collisionCircle.dynamicVertices));
+            }
+        }
     }
 
+    if (!staticUploaded) {
+        for (auto& pair : paintPropertyBinders) {
+            pair.second.first.upload(context);
+            pair.second.second.upload(context);
+        }
+    }
+    
     uploaded = true;
+    staticUploaded = true;
+    placementChangesUploaded = true;
+    dynamicUploaded = true;
+    sortUploaded = true;
 }
 
 bool SymbolBucket::hasData() const {
@@ -76,4 +136,82 @@ bool SymbolBucket::hasCollisionBoxData() const {
     return !collisionBox.segments.empty();
 }
 
+bool SymbolBucket::hasCollisionCircleData() const {
+    return !collisionCircle.segments.empty();
+}
+
+void SymbolBucket::updateOpacity() {
+    placementChangesUploaded = false;
+    uploaded = false;
+}
+
+void addPlacedSymbol(gl::IndexVector<gl::Triangles>& triangles, const PlacedSymbol& placedSymbol) {
+    auto endIndex = placedSymbol.vertexStartIndex + placedSymbol.glyphOffsets.size() * 4;
+    for (auto vertexIndex = placedSymbol.vertexStartIndex; vertexIndex < endIndex; vertexIndex += 4) {
+        triangles.emplace_back(vertexIndex + 0, vertexIndex + 1, vertexIndex + 2);
+        triangles.emplace_back(vertexIndex + 1, vertexIndex + 2, vertexIndex + 3);
+    }
+}
+
+void SymbolBucket::sortFeatures(const float angle) {
+    if (!sortFeaturesByY) {
+        return;
+    }
+
+    if (sortedAngle && *sortedAngle == angle) {
+        return;
+    }
+    
+    sortedAngle = angle;
+
+    // The current approach to sorting doesn't sort across segments so don't try.
+    // Sorting within segments separately seemed not to be worth the complexity.
+    if (text.segments.size() > 1 || icon.segments.size() > 1) {
+        return;
+    }
+    
+    sortUploaded = false;
+    uploaded = false;
+
+    // If the symbols are allowed to overlap sort them by their vertical screen position.
+    // The index array buffer is rewritten to reference the (unchanged) vertices in the
+    // sorted order.
+
+    // To avoid sorting the actual symbolInstance array we sort an array of indexes.
+    std::vector<size_t> symbolInstanceIndexes;
+    for (size_t i = 0; i < symbolInstances.size(); i++) {
+        symbolInstanceIndexes.push_back(i);
+    }
+    
+    const float sin = std::sin(angle);
+    const float cos = std::cos(angle);
+
+    std::sort(symbolInstanceIndexes.begin(), symbolInstanceIndexes.end(), [sin, cos, this](size_t &aIndex, size_t &bIndex) {
+        const SymbolInstance& a = symbolInstances[aIndex];
+        const SymbolInstance& b = symbolInstances[bIndex];
+        const int32_t aRotated = sin * a.anchor.point.x + cos * a.anchor.point.y;
+        const int32_t bRotated = sin * b.anchor.point.x + cos * b.anchor.point.y;
+        return aRotated != bRotated ?
+            aRotated < bRotated :
+            a.index > b.index;
+    });
+
+    text.triangles.clear();
+    icon.triangles.clear();
+
+    for (auto i : symbolInstanceIndexes) {
+        const SymbolInstance& symbolInstance = symbolInstances[i];
+
+        if (symbolInstance.placedTextIndex) {
+            addPlacedSymbol(text.triangles, text.placedSymbols[*symbolInstance.placedTextIndex]);
+        }
+        if (symbolInstance.placedVerticalTextIndex) {
+            addPlacedSymbol(text.triangles, text.placedSymbols[*symbolInstance.placedVerticalTextIndex]);
+        }
+        if (symbolInstance.placedIconIndex) {
+            addPlacedSymbol(icon.triangles, icon.placedSymbols[*symbolInstance.placedIconIndex]);
+        }
+    }
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/buckets/symbol_bucket.hpp b/src/mbgl/renderer/buckets/symbol_bucket.hpp
index 32f976bcb2..4abea90508 100644
--- a/src/mbgl/renderer/buckets/symbol_bucket.hpp
+++ b/src/mbgl/renderer/buckets/symbol_bucket.hpp
@@ -10,6 +10,7 @@
 #include <mbgl/text/glyph_range.hpp>
 #include <mbgl/style/layers/symbol_layer_properties.hpp>
 #include <mbgl/layout/symbol_feature.hpp>
+#include <mbgl/layout/symbol_instance.hpp>
 
 #include <vector>
 
@@ -18,18 +19,22 @@ namespace mbgl {
 class PlacedSymbol {
 public:
     PlacedSymbol(Point<float> anchorPoint_, uint16_t segment_, float lowerSize_, float upperSize_,
-            std::array<float, 2> lineOffset_, float placementZoom_, bool useVerticalMode_, GeometryCoordinates line_) :
+            std::array<float, 2> lineOffset_, WritingModeType writingModes_, GeometryCoordinates line_, std::vector<float> tileDistances_) :
         anchorPoint(anchorPoint_), segment(segment_), lowerSize(lowerSize_), upperSize(upperSize_),
-        lineOffset(lineOffset_), placementZoom(placementZoom_), useVerticalMode(useVerticalMode_), line(std::move(line_)) {}
+        lineOffset(lineOffset_), writingModes(writingModes_), line(std::move(line_)), tileDistances(std::move(tileDistances_)), hidden(false), vertexStartIndex(0)
+    {
+    }
     Point<float> anchorPoint;
     uint16_t segment;
     float lowerSize;
     float upperSize;
     std::array<float, 2> lineOffset;
-    float placementZoom;
-    bool useVerticalMode;
+    WritingModeType writingModes;
     GeometryCoordinates line;
+    std::vector<float> tileDistances;
     std::vector<float> glyphOffsets;
+    bool hidden;
+    size_t vertexStartIndex;
 };
 
 class SymbolBucket : public Bucket {
@@ -40,17 +45,33 @@ public:
                  const style::DataDrivenPropertyValue<float>& iconSize,
                  float zoom,
                  bool sdfIcons,
-                 bool iconsNeedLinear);
+                 bool iconsNeedLinear,
+                 bool sortFeaturesByY,
+                 const std::vector<SymbolInstance>&&);
 
     void upload(gl::Context&) override;
     bool hasData() const override;
     bool hasTextData() const;
     bool hasIconData() const;
     bool hasCollisionBoxData() const;
+    bool hasCollisionCircleData() const;
+    
+    void updateOpacity();
+    void sortFeatures(const float angle);
 
     const style::SymbolLayoutProperties::PossiblyEvaluated layout;
     const bool sdfIcons;
     const bool iconsNeedLinear;
+    const bool sortFeaturesByY;
+    
+    optional<float> sortedAngle;
+
+    bool staticUploaded = false;
+    bool placementChangesUploaded = false;
+    bool dynamicUploaded = false;
+    bool sortUploaded = false;
+
+    std::vector<SymbolInstance> symbolInstances;
 
     std::map<std::string, std::pair<
         SymbolIconProgram::PaintPropertyBinders,
@@ -61,12 +82,14 @@ public:
     struct TextBuffer {
         gl::VertexVector<SymbolLayoutVertex> vertices;
         gl::VertexVector<SymbolDynamicLayoutAttributes::Vertex> dynamicVertices;
+        gl::VertexVector<SymbolOpacityAttributes::Vertex> opacityVertices;
         gl::IndexVector<gl::Triangles> triangles;
         SegmentVector<SymbolTextAttributes> segments;
         std::vector<PlacedSymbol> placedSymbols;
 
         optional<gl::VertexBuffer<SymbolLayoutVertex>> vertexBuffer;
         optional<gl::VertexBuffer<SymbolDynamicLayoutAttributes::Vertex>> dynamicVertexBuffer;
+        optional<gl::VertexBuffer<SymbolOpacityAttributes::Vertex>> opacityVertexBuffer;
         optional<gl::IndexBuffer<gl::Triangles>> indexBuffer;
     } text;
     
@@ -75,6 +98,7 @@ public:
     struct IconBuffer {
         gl::VertexVector<SymbolLayoutVertex> vertices;
         gl::VertexVector<SymbolDynamicLayoutAttributes::Vertex> dynamicVertices;
+        gl::VertexVector<SymbolOpacityAttributes::Vertex> opacityVertices;
         gl::IndexVector<gl::Triangles> triangles;
         SegmentVector<SymbolIconAttributes> segments;
         std::vector<PlacedSymbol> placedSymbols;
@@ -82,18 +106,30 @@ public:
 
         optional<gl::VertexBuffer<SymbolLayoutVertex>> vertexBuffer;
         optional<gl::VertexBuffer<SymbolDynamicLayoutAttributes::Vertex>> dynamicVertexBuffer;
+        optional<gl::VertexBuffer<SymbolOpacityAttributes::Vertex>> opacityVertexBuffer;
         optional<gl::IndexBuffer<gl::Triangles>> indexBuffer;
     } icon;
 
-    struct CollisionBoxBuffer {
-        gl::VertexVector<CollisionBoxVertex> vertices;
-        gl::IndexVector<gl::Lines> lines;
-        SegmentVector<CollisionBoxAttributes> segments;
+    struct CollisionBuffer {
+        gl::VertexVector<CollisionBoxLayoutAttributes::Vertex> vertices;
+        gl::VertexVector<CollisionBoxDynamicAttributes::Vertex> dynamicVertices;
+        SegmentVector<CollisionBoxProgram::Attributes> segments;
 
-        optional<gl::VertexBuffer<CollisionBoxVertex>> vertexBuffer;
-        optional<gl::VertexBuffer<SymbolDynamicLayoutAttributes::Vertex>> dynamicVertexBuffer;
+        optional<gl::VertexBuffer<CollisionBoxLayoutAttributes::Vertex>> vertexBuffer;
+        optional<gl::VertexBuffer<CollisionBoxDynamicAttributes::Vertex>> dynamicVertexBuffer;
+    };
+
+    struct CollisionBoxBuffer : public CollisionBuffer {
+        gl::IndexVector<gl::Lines> lines;
         optional<gl::IndexBuffer<gl::Lines>> indexBuffer;
     } collisionBox;
+    
+    struct CollisionCircleBuffer : public CollisionBuffer {
+        gl::IndexVector<gl::Triangles> triangles;
+        optional<gl::IndexBuffer<gl::Triangles>> indexBuffer;
+    } collisionCircle;
+
+    uint32_t bucketInstanceId = 0;
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/renderer/paint_parameters.hpp b/src/mbgl/renderer/paint_parameters.hpp
index 60f5af4e9a..8d9a57955f 100644
--- a/src/mbgl/renderer/paint_parameters.hpp
+++ b/src/mbgl/renderer/paint_parameters.hpp
@@ -74,6 +74,8 @@ public:
     uint32_t currentLayer;
     float depthRangeSize;
     const float depthEpsilon = 1.0f / (1 << 16);
+    
+    float symbolFadeChange;
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/renderer/render_layer.hpp b/src/mbgl/renderer/render_layer.hpp
index dfc6bcf2fd..aa5777a186 100644
--- a/src/mbgl/renderer/render_layer.hpp
+++ b/src/mbgl/renderer/render_layer.hpp
@@ -81,14 +81,13 @@ public:
 
     friend std::string layoutKey(const RenderLayer&);
 
+    // Stores current set of tiles to be rendered for this layer.
+    std::vector<std::reference_wrapper<RenderTile>> renderTiles;
+
 protected:
     // Stores what render passes this layer is currently enabled for. This depends on the
     // evaluated StyleProperties object and is updated accordingly.
     RenderPass passes = RenderPass::None;
-
-    //Stores current set of tiles to be rendered for this layer.
-    std::vector<std::reference_wrapper<RenderTile>> renderTiles;
-
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/renderer/renderer_impl.cpp b/src/mbgl/renderer/renderer_impl.cpp
index 5987e69374..7cc92f6d7d 100644
--- a/src/mbgl/renderer/renderer_impl.cpp
+++ b/src/mbgl/renderer/renderer_impl.cpp
@@ -23,6 +23,7 @@
 #include <mbgl/style/source_impl.hpp>
 #include <mbgl/style/transition_options.hpp>
 #include <mbgl/text/glyph_manager.hpp>
+#include <mbgl/text/cross_tile_symbol_index.hpp>
 #include <mbgl/tile/tile.hpp>
 #include <mbgl/util/math.hpp>
 #include <mbgl/util/string.hpp>
@@ -56,7 +57,9 @@ Renderer::Impl::Impl(RendererBackend& backend_,
     , imageImpls(makeMutable<std::vector<Immutable<style::Image::Impl>>>())
     , sourceImpls(makeMutable<std::vector<Immutable<style::Source::Impl>>>())
     , layerImpls(makeMutable<std::vector<Immutable<style::Layer::Impl>>>())
-    , renderLight(makeMutable<Light::Impl>()) {
+    , renderLight(makeMutable<Light::Impl>())
+    , crossTileSymbolIndex(std::make_unique<CrossTileSymbolIndex>())
+    , placement(std::make_unique<Placement>(TransformState{}, MapMode::Still)) {
     glyphManager->setObserver(this);
 }
 
@@ -348,26 +351,6 @@ void Renderer::Impl::render(const UpdateParameters& updateParameters) {
                 continue;
             }
 
-            // We're not clipping symbol layers, so when we have both parents and children of symbol
-            // layers, we drop all children in favor of their parent to avoid duplicate labels.
-            // See https://github.com/mapbox/mapbox-gl-native/issues/2482
-            if (symbolLayer) {
-                bool skip = false;
-                // Look back through the buckets we decided to render to find out whether there is
-                // already a bucket from this layer that is a parent of this tile. Tiles are ordered
-                // by zoom level when we obtain them from getTiles().
-                for (auto it = sortedTilesForInsertion.rbegin();
-                     it != sortedTilesForInsertion.rend(); ++it) {
-                    if (tile.tile.id.isChildOf(it->get().tile.id)) {
-                        skip = true;
-                        break;
-                    }
-                }
-                if (skip) {
-                    continue;
-                }
-            }
-
             auto bucket = tile.tile.getBucket(*layer->baseImpl);
             if (bucket) {
                 sortedTilesForInsertion.emplace_back(tile);
@@ -388,6 +371,45 @@ void Renderer::Impl::render(const UpdateParameters& updateParameters) {
     frameHistory.record(parameters.timePoint,
                         parameters.state.getZoom(),
                         parameters.mapMode == MapMode::Continuous ? util::DEFAULT_TRANSITION_DURATION : Milliseconds(0));
+    bool symbolBucketsChanged = false;
+    if (parameters.mapMode == MapMode::Still) {
+        // TODO: Think about right way for symbol index to handle still rendering
+        crossTileSymbolIndex->reset();
+    }
+    for (auto it = order.rbegin(); it != order.rend(); ++it) {
+        if (it->layer.is<RenderSymbolLayer>()) {
+            if (crossTileSymbolIndex->addLayer(*it->layer.as<RenderSymbolLayer>())) symbolBucketsChanged = true;
+        }
+    }
+
+    bool placementChanged = false;
+    if (!placement->stillRecent(parameters.timePoint)) {
+        auto newPlacement = std::make_unique<Placement>(parameters.state, parameters.mapMode);
+        for (auto it = order.rbegin(); it != order.rend(); ++it) {
+            if (it->layer.is<RenderSymbolLayer>()) {
+                newPlacement->placeLayer(*it->layer.as<RenderSymbolLayer>(), parameters.projMatrix, parameters.debugOptions & MapDebugOptions::Collision);
+            }
+        }
+
+        placementChanged = newPlacement->commit(*placement, parameters.timePoint);
+        if (placementChanged || symbolBucketsChanged) {
+            placement = std::move(newPlacement);
+        }
+
+        placement->setRecent(parameters.timePoint);
+    } else {
+        placement->setStale();
+    }
+
+    parameters.symbolFadeChange = placement->symbolFadeChange(parameters.timePoint);
+
+    if (placementChanged || symbolBucketsChanged) {
+        for (auto it = order.rbegin(); it != order.rend(); ++it) {
+            if (it->layer.is<RenderSymbolLayer>()) {
+                placement->updateLayerOpacities(*it->layer.as<RenderSymbolLayer>());
+            }
+        }
+    }
 
     // - UPLOAD PASS -------------------------------------------------------------------------------
     // Uploads all required buffers and images before we do any actual rendering.
@@ -607,7 +629,7 @@ void Renderer::Impl::render(const UpdateParameters& updateParameters) {
 
     observer->onDidFinishRenderingFrame(
         loaded ? RendererObserver::RenderMode::Full : RendererObserver::RenderMode::Partial,
-        updateParameters.mode == MapMode::Continuous && (hasTransitions() || frameHistory.needsAnimation(util::DEFAULT_TRANSITION_DURATION))
+        updateParameters.mode == MapMode::Continuous && (hasTransitions(parameters.timePoint))
     );
 
     if (!loaded) {
@@ -647,7 +669,7 @@ std::vector<Feature> Renderer::Impl::queryRenderedFeatures(const ScreenLineStrin
     std::unordered_map<std::string, std::vector<Feature>> resultsByLayer;
     for (const auto& sourceID : sourceIDs) {
         if (RenderSource* renderSource = getRenderSource(sourceID)) {
-            auto sourceResults = renderSource->queryRenderedFeatures(geometry, transformState, layers, options);
+            auto sourceResults = renderSource->queryRenderedFeatures(geometry, transformState, layers, options, placement->getCollisionIndex());
             std::move(sourceResults.begin(), sourceResults.end(), std::inserter(resultsByLayer, resultsByLayer.begin()));
         }
     }
@@ -727,7 +749,7 @@ RenderSource* Renderer::Impl::getRenderSource(const std::string& id) const {
     return it != renderSources.end() ? it->second.get() : nullptr;
 }
 
-bool Renderer::Impl::hasTransitions() const {
+bool Renderer::Impl::hasTransitions(TimePoint timePoint) const {
     if (renderLight.hasTransition()) {
         return true;
     }
@@ -738,6 +760,10 @@ bool Renderer::Impl::hasTransitions() const {
         }
     }
 
+    if (placement->hasTransitions(timePoint)) {
+        return true;
+    }
+
     return false;
 }
 
diff --git a/src/mbgl/renderer/renderer_impl.hpp b/src/mbgl/renderer/renderer_impl.hpp
index 720e01ed53..e4cc893d07 100644
--- a/src/mbgl/renderer/renderer_impl.hpp
+++ b/src/mbgl/renderer/renderer_impl.hpp
@@ -11,6 +11,7 @@
 #include <mbgl/map/transform_state.hpp>
 #include <mbgl/map/zoom_history.hpp>
 #include <mbgl/text/glyph_manager_observer.hpp>
+#include <mbgl/text/placement.hpp>
 
 #include <memory>
 #include <string>
@@ -31,6 +32,7 @@ class Scheduler;
 class GlyphManager;
 class ImageManager;
 class LineAtlas;
+class CrossTileSymbolIndex;
 
 class Renderer::Impl : public GlyphManagerObserver,
                        public RenderSourceObserver{
@@ -56,7 +58,7 @@ public:
 
 private:
     bool isLoaded() const;
-    bool hasTransitions() const;
+    bool hasTransitions(TimePoint) const;
 
     RenderSource* getRenderSource(const std::string& id) const;
 
@@ -108,6 +110,9 @@ private:
     std::unordered_map<std::string, std::unique_ptr<RenderLayer>> renderLayers;
     RenderLight renderLight;
 
+    std::unique_ptr<CrossTileSymbolIndex> crossTileSymbolIndex;
+    std::unique_ptr<Placement> placement;
+
     bool contextLost = false;
 };
 
diff --git a/src/mbgl/renderer/tile_pyramid.cpp b/src/mbgl/renderer/tile_pyramid.cpp
index 3e2311089d..f3ee787442 100644
--- a/src/mbgl/renderer/tile_pyramid.cpp
+++ b/src/mbgl/renderer/tile_pyramid.cpp
@@ -5,7 +5,6 @@
 #include <mbgl/renderer/tile_parameters.hpp>
 #include <mbgl/renderer/query.hpp>
 #include <mbgl/map/transform.hpp>
-#include <mbgl/text/placement_config.hpp>
 #include <mbgl/math/clamp.hpp>
 #include <mbgl/util/tile_cover.hpp>
 #include <mbgl/util/enum.hpp>
@@ -120,6 +119,7 @@ void TilePyramid::update(const std::vector<Immutable<style::Layer::Impl>>& layer
     // use because they're still loading. In addition to that, we also need to retain all tiles that
     // we're actively using, e.g. as a replacement for tile that aren't loaded yet.
     std::set<OverscaledTileID> retain;
+    std::set<UnwrappedTileID> rendered;
 
     auto retainTileFn = [&](Tile& tile, TileNecessity necessity) -> void {
         if (retain.emplace(tile.id).second) {
@@ -150,6 +150,7 @@ void TilePyramid::update(const std::vector<Immutable<style::Layer::Impl>>& layer
     };
     auto renderTileFn = [&](const UnwrappedTileID& tileID, Tile& tile) {
         renderTiles.emplace_back(tileID, tile);
+        rendered.emplace(tileID);
     };
 
     renderTiles.clear();
@@ -177,6 +178,13 @@ void TilePyramid::update(const std::vector<Immutable<style::Layer::Impl>>& layer
         auto tilesIt = tiles.begin();
         auto retainIt = retain.begin();
         while (tilesIt != tiles.end()) {
+            auto renderedIt = rendered.find(tilesIt->first.toUnwrapped());
+            if (renderedIt == rendered.end()) {
+                // Since this tile isn't in the render set, crossTileIDs won't be kept
+                // updated by CrossTileSymbolIndex. We need to reset the stored crossTileIDs
+                // so they're not reused if/when this tile is re-added to the render set
+                tilesIt->second->resetCrossTileIDs();
+            }
             if (retainIt == retain.end() || tilesIt->first < *retainIt) {
                 if (!needsRelayout) {
                     tilesIt->second->setNecessity(TileNecessity::Optional);
@@ -193,13 +201,7 @@ void TilePyramid::update(const std::vector<Immutable<style::Layer::Impl>>& layer
     }
 
     for (auto& pair : tiles) {
-        const PlacementConfig config { parameters.transformState.getAngle(),
-                                       parameters.transformState.getPitch(),
-                                       parameters.transformState.getCameraToCenterDistance(),
-                                       parameters.transformState.getCameraToTileDistance(pair.first.toUnwrapped()),
-                                       parameters.debugOptions & MapDebugOptions::Collision };
-
-        pair.second->setPlacementConfig(config);
+        pair.second->setShowCollisionBoxes(parameters.debugOptions & MapDebugOptions::Collision);
     }
 }
 
diff --git a/src/mbgl/text/collision_feature.cpp b/src/mbgl/text/collision_feature.cpp
index 3eb08da8d1..6d6f2aabc7 100644
--- a/src/mbgl/text/collision_feature.cpp
+++ b/src/mbgl/text/collision_feature.cpp
@@ -13,8 +13,9 @@ CollisionFeature::CollisionFeature(const GeometryCoordinates& line,
                                    const float padding,
                                    const style::SymbolPlacementType placement,
                                    IndexedSubfeature indexedFeature_,
-                                   const AlignmentType alignment)
-        : indexedFeature(std::move(indexedFeature_)) {
+                                   const float overscaling)
+        : indexedFeature(std::move(indexedFeature_))
+        , alongLine(placement == style::SymbolPlacementType::Line) {
     if (top == 0 && bottom == 0 && left == 0 && right == 0) return;
 
     const float y1 = top * boxScale - padding;
@@ -22,7 +23,7 @@ CollisionFeature::CollisionFeature(const GeometryCoordinates& line,
     const float x1 = left * boxScale - padding;
     const float x2 = right * boxScale + padding;
 
-    if (placement == style::SymbolPlacementType::Line) {
+    if (alongLine) {
         float height = y2 - y1;
         const double length = x2 - x1;
 
@@ -31,29 +32,26 @@ CollisionFeature::CollisionFeature(const GeometryCoordinates& line,
         height = std::max(10.0f * boxScale, height);
 
         GeometryCoordinate anchorPoint = convertPoint<int16_t>(anchor.point);
-
-        if (alignment == AlignmentType::Straight) {
-            // used for icon labels that are aligned with the line, but don't curve along it
-            const GeometryCoordinate vector = convertPoint<int16_t>(util::unit(convertPoint<double>(line[anchor.segment + 1] - line[anchor.segment])) * length);
-            const GeometryCoordinates newLine({ anchorPoint - vector, anchorPoint + vector });
-            bboxifyLabel(newLine, anchorPoint, 0, length, height);
-        } else {
-            // used for text labels that curve along a line
-            bboxifyLabel(line, anchorPoint, anchor.segment, length, height);
-        }
+        bboxifyLabel(line, anchorPoint, anchor.segment, length, height, overscaling);
     } else {
-        boxes.emplace_back(anchor.point, Point<float>{ 0, 0 }, x1, y1, x2, y2, std::numeric_limits<float>::infinity());
+        boxes.emplace_back(anchor.point, Point<float>{ 0, 0 }, x1, y1, x2, y2);
     }
 }
 
 void CollisionFeature::bboxifyLabel(const GeometryCoordinates& line, GeometryCoordinate& anchorPoint,
-                                    const int segment, const float labelLength, const float boxSize) {
+                                    const int segment, const float labelLength, const float boxSize, const float overscaling) {
     const float step = boxSize / 2;
     const int nBoxes = std::floor(labelLength / step);
-    // We calculate line collision boxes out to 300% of what would normally be our
+    // We calculate line collision circles out to 300% of what would normally be our
     // max size, to allow collision detection to work on labels that expand as
     // they move into the distance
-    const int nPitchPaddingBoxes = std::floor(nBoxes / 2);
+    // Vertically oriented labels in the distant field can extend past this padding
+    // This is a noticeable problem in overscaled tiles where the pitch 0-based
+    // symbol spacing will put labels very close together in a pitched map.
+    // To reduce the cost of adding extra collision circles, we slowly increase
+    // them for overscaled tiles.
+    const float overscalingPaddingFactor = 1 + .4 * std::log(overscaling) / std::log(2);
+    const int nPitchPaddingBoxes = std::floor(nBoxes * overscalingPaddingFactor / 2);
 
     // offset the center of the first box by half a box so that the edge of the
     // box is at the edge of the label.
@@ -124,47 +122,18 @@ void CollisionFeature::bboxifyLabel(const GeometryCoordinates& line, GeometryCoo
             p0.x + segmentBoxDistance / segmentLength * (p1.x - p0.x),
             p0.y + segmentBoxDistance / segmentLength * (p1.y - p0.y)
         };
-
-        // Distance from label anchor point to inner (towards center) edge of this box
-        // The tricky thing here is that box positioning doesn't change with scale,
-        // but box size does change with scale.
-        // Technically, distanceToInnerEdge should be:
-        // Math.max(Math.abs(boxDistanceToAnchor - firstBoxOffset) - (step / scale), 0);
-        // But using that formula would make solving for maxScale more difficult, so we
-        // approximate with scale=2.
-        // This makes our calculation spot-on at scale=2, and on the conservative side for
-        // lower scales
-        const float distanceToInnerEdge = std::max(std::fabs(boxDistanceToAnchor - firstBoxOffset) - step / 2, 0.0f);
-        float maxScale = util::division(labelLength / 2, distanceToInnerEdge, std::numeric_limits<float>::infinity());
-
-        // The box maxScale calculations are designed to be conservative on collisions in the scale range
-        // [1,2]. At scale=1, each box has 50% overlap, and at scale=2, the boxes are lined up edge
-        // to edge (beyond scale 2, gaps start to appear, which could potentially allow missed collisions).
-        // We add "pitch padding" boxes to the left and right to handle effective underzooming
-        // (scale < 1) when labels are in the distance. The overlap approximation could cause us to use
-        // these boxes when the scale is greater than 1, but we prevent that because we know
-        // they're only necessary for scales less than one.
-        // This preserves the pre-pitch-padding behavior for unpitched maps.
-        if (i < 0 || i >= nBoxes) {
-            maxScale = std::min(maxScale, 0.99f);
-        }
-
-        boxes.emplace_back(boxAnchor, boxAnchor - convertPoint<float>(anchorPoint), -boxSize / 2, -boxSize / 2, boxSize / 2, boxSize / 2, maxScale);
+        
+        // If the box is within boxSize of the anchor, force the box to be used
+        // (so even 0-width labels use at least one box)
+        // Otherwise, the .8 multiplication gives us a little bit of conservative
+        // padding in choosing which boxes to use (see CollisionIndex#placedCollisionCircles)
+        const float paddedAnchorDistance = std::abs(boxDistanceToAnchor - firstBoxOffset) < step ?
+            0 :
+            (boxDistanceToAnchor - firstBoxOffset) * 0.8;
+
+        boxes.emplace_back(boxAnchor, boxAnchor - convertPoint<float>(anchorPoint), -boxSize / 2, -boxSize / 2, boxSize / 2, boxSize / 2, paddedAnchorDistance, boxSize / 2);
     }
 }
 
-float CollisionBox::adjustedMaxScale(const std::array<float, 4>& rotationMatrix, const float yStretch) const {
-    // When the map is pitched the distance covered by a line changes.
-    // Adjust the max scale by (approximatePitchedLength / approximateRegularLength)
-    // to compensate for this.
-    const Point<float> rotatedOffset = util::matrixMultiply(rotationMatrix, offset);
-    const float xSqr = rotatedOffset.x * rotatedOffset.x;
-    const float ySqr = rotatedOffset.y * rotatedOffset.y;
-    const float yStretchSqr = ySqr * yStretch * yStretch;
-    const float adjustmentFactor = xSqr + ySqr != 0 ?
-        std::sqrt((xSqr + yStretchSqr) / (xSqr + ySqr)) :
-        1.0f;
-    return maxScale * adjustmentFactor;
-}
 
 } // namespace mbgl
diff --git a/src/mbgl/text/collision_feature.hpp b/src/mbgl/text/collision_feature.hpp
index 3b6e461a26..4ecd25c717 100644
--- a/src/mbgl/text/collision_feature.hpp
+++ b/src/mbgl/text/collision_feature.hpp
@@ -11,10 +11,8 @@ namespace mbgl {
 
 class CollisionBox {
 public:
-    CollisionBox(Point<float> _anchor, Point<float> _offset, float _x1, float _y1, float _x2, float _y2, float _maxScale) :
-        anchor(std::move(_anchor)), offset(_offset), x1(_x1), y1(_y1), x2(_x2), y2(_y2), maxScale(_maxScale) {}
-
-    float adjustedMaxScale(const std::array<float, 4>& rotationMatrix, const float yStretch) const;
+    CollisionBox(Point<float> _anchor, Point<float> _offset, float _x1, float _y1, float _x2, float _y2, float _signedDistanceFromAnchor = 0, float _radius = 0) :
+        anchor(std::move(_anchor)), offset(_offset), x1(_x1), y1(_y1), x2(_x2), y2(_y2), used(true), signedDistanceFromAnchor(_signedDistanceFromAnchor), radius(_radius) {}
 
     // the box is centered around the anchor point
     Point<float> anchor;
@@ -28,20 +26,23 @@ public:
     float x2;
     float y2;
 
-    // the box is only valid for scales < maxScale.
-    // The box does not block other boxes at scales >= maxScale;
-    float maxScale;
+    // Projected box geometry: generated/updated at placement time
+    float px1;
+    float py1;
+    float px2;
+    float py2;
+    
+    // Projected circle geometry: generated/updated at placement time
+    float px;
+    float py;
+    bool used;
 
-    // the scale at which the label can first be shown
-    float placementScale = 0.0f;
+    float signedDistanceFromAnchor;
+    float radius;
 };
 
 class CollisionFeature {
 public:
-    enum class AlignmentType : bool {
-        Straight = false,
-        Curved
-    };
 
     // for text
     CollisionFeature(const GeometryCoordinates& line,
@@ -50,8 +51,9 @@ public:
                      const float boxScale,
                      const float padding,
                      const style::SymbolPlacementType placement,
-                     const IndexedSubfeature& indexedFeature_)
-        : CollisionFeature(line, anchor, shapedText.top, shapedText.bottom, shapedText.left, shapedText.right, boxScale, padding, placement, indexedFeature_, AlignmentType::Curved) {}
+                     const IndexedSubfeature& indexedFeature_,
+                     const float overscaling)
+        : CollisionFeature(line, anchor, shapedText.top, shapedText.bottom, shapedText.left, shapedText.right, boxScale, padding, placement, indexedFeature_, overscaling) {}
 
     // for icons
     CollisionFeature(const GeometryCoordinates& line,
@@ -66,7 +68,7 @@ public:
                            (shapedIcon ? shapedIcon->bottom() : 0),
                            (shapedIcon ? shapedIcon->left() : 0),
                            (shapedIcon ? shapedIcon->right() : 0),
-                           boxScale, padding, placement, indexedFeature_, AlignmentType::Straight) {}
+                           boxScale, padding, placement, indexedFeature_, 1) {}
 
     CollisionFeature(const GeometryCoordinates& line,
                      const Anchor&,
@@ -78,14 +80,15 @@ public:
                      const float padding,
                      const style::SymbolPlacementType,
                      IndexedSubfeature,
-                     const AlignmentType);
+                     const float overscaling);
 
     std::vector<CollisionBox> boxes;
     IndexedSubfeature indexedFeature;
+    bool alongLine;
 
 private:
     void bboxifyLabel(const GeometryCoordinates& line, GeometryCoordinate& anchorPoint,
-                      const int segment, const float length, const float height);
+                      const int segment, const float length, const float height, const float overscaling);
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/text/placement.cpp b/src/mbgl/text/placement.cpp
index ac8c15aae9..b9f270d52e 100644
--- a/src/mbgl/text/placement.cpp
+++ b/src/mbgl/text/placement.cpp
@@ -62,13 +62,13 @@ void Placement::placeLayer(RenderSymbolLayer& symbolLayer, const mat4& projMatri
         state.matrixFor(posMatrix, renderTile.id);
         matrix::multiply(posMatrix, projMatrix, posMatrix);
 
-        mat4 textLabelPlaneMatrix = getLabelPlaneMatrix(renderTile.matrix,
+        mat4 textLabelPlaneMatrix = getLabelPlaneMatrix(posMatrix,
                 layout.get<TextPitchAlignment>() == style::AlignmentType::Map,
                 layout.get<TextRotationAlignment>() == style::AlignmentType::Map,
                 state,
                 pixelsToTileUnits);
 
-        mat4 iconLabelPlaneMatrix = getLabelPlaneMatrix(renderTile.matrix,
+        mat4 iconLabelPlaneMatrix = getLabelPlaneMatrix(posMatrix,
                 layout.get<IconPitchAlignment>() == style::AlignmentType::Map,
                 layout.get<IconRotationAlignment>() == style::AlignmentType::Map,
                 state,
diff --git a/src/mbgl/tile/geometry_tile.cpp b/src/mbgl/tile/geometry_tile.cpp
index 8c018ce3aa..576c23b682 100644
--- a/src/mbgl/tile/geometry_tile.cpp
+++ b/src/mbgl/tile/geometry_tile.cpp
@@ -15,7 +15,6 @@
 #include <mbgl/renderer/image_atlas.hpp>
 #include <mbgl/storage/file_source.hpp>
 #include <mbgl/geometry/feature_index.hpp>
-#include <mbgl/text/collision_tile.hpp>
 #include <mbgl/map/transform_state.hpp>
 #include <mbgl/style/filter_evaluator.hpp>
 #include <mbgl/util/logging.hpp>
@@ -33,7 +32,7 @@ using namespace style;
 
    GeometryTile's 'correlationID' is used for ensuring the tile will be flagged
    as non-pending only when the placement coming from the last operation (as in
-   'setData', 'setLayers',  'setPlacementConfig') occurs. This is important for
+   'setData', 'setLayers',  'setShowCollisionBoxes') occurs. This is important for
    still mode rendering as we want to render only when all layout and placement
    operations are completed.
 
@@ -52,13 +51,15 @@ GeometryTile::GeometryTile(const OverscaledTileID& id_,
       worker(parameters.workerScheduler,
              ActorRef<GeometryTile>(*this, mailbox),
              id_,
+             sourceID,
              obsolete,
              parameters.mode,
-             parameters.pixelRatio),
+             parameters.pixelRatio,
+             parameters.debugOptions & MapDebugOptions::Collision),
       glyphManager(parameters.glyphManager),
       imageManager(parameters.imageManager),
-      lastYStretch(1.0f),
-      mode(parameters.mode) {
+      mode(parameters.mode),
+      showCollisionBoxes(parameters.debugOptions & MapDebugOptions::Collision) {
 }
 
 GeometryTile::~GeometryTile() {
@@ -89,25 +90,6 @@ void GeometryTile::setData(std::unique_ptr<const GeometryTileData> data_) {
     worker.invoke(&GeometryTileWorker::setData, std::move(data_), correlationID);
 }
 
-void GeometryTile::setPlacementConfig(const PlacementConfig& desiredConfig) {
-    if (requestedConfig == desiredConfig) {
-        return;
-    }
-
-    // Mark the tile as pending again if it was complete before to prevent signaling a complete
-    // state despite pending parse operations.
-    pending = true;
-
-    ++correlationID;
-    requestedConfig = desiredConfig;
-    invokePlacement();
-}
-
-void GeometryTile::invokePlacement() {
-    if (requestedConfig) {
-        worker.invoke(&GeometryTileWorker::setPlacementConfig, *requestedConfig, correlationID);
-    }
-}
 
 void GeometryTile::setLayers(const std::vector<Immutable<Layer::Impl>>& layers) {
     // Mark the tile as pending again if it was complete before to prevent signaling a complete
@@ -134,14 +116,22 @@ void GeometryTile::setLayers(const std::vector<Immutable<Layer::Impl>>& layers)
     worker.invoke(&GeometryTileWorker::setLayers, std::move(impls), correlationID);
 }
 
+void GeometryTile::setShowCollisionBoxes(const bool showCollisionBoxes_) {
+    if (showCollisionBoxes != showCollisionBoxes_) {
+       showCollisionBoxes = showCollisionBoxes_;
+       ++correlationID;
+        worker.invoke(&GeometryTileWorker::setShowCollisionBoxes, showCollisionBoxes, correlationID);
+    }
+}
+
 void GeometryTile::onLayout(LayoutResult result, const uint64_t resultCorrelationID) {
-    loaded = true;
-    renderable = true;
+    // Don't mark ourselves loaded or renderable until the first successful placement
+    // TODO: Ideally we'd render this tile without symbols as long as this tile wasn't
+    //  replacing a tile at a different zoom that _did_ have symbols.
     (void)resultCorrelationID;
     nonSymbolBuckets = std::move(result.nonSymbolBuckets);
     featureIndex = std::move(result.featureIndex);
     data = std::move(result.tileData);
-    collisionTile.reset();
     observer->onTileChanged(*this);
 }
 
@@ -152,16 +142,13 @@ void GeometryTile::onPlacement(PlacementResult result, const uint64_t resultCorr
         pending = false;
     }
     symbolBuckets = std::move(result.symbolBuckets);
-    collisionTile = std::move(result.collisionTile);
     if (result.glyphAtlasImage) {
         glyphAtlasImage = std::move(*result.glyphAtlasImage);
     }
     if (result.iconAtlasImage) {
         iconAtlasImage = std::move(*result.iconAtlasImage);
     }
-    if (collisionTile.get()) {
-        lastYStretch = collisionTile->yStretch;
-    }
+
     observer->onTileChanged(*this);
 }
 
@@ -231,7 +218,8 @@ void GeometryTile::queryRenderedFeatures(
     const GeometryCoordinates& queryGeometry,
     const TransformState& transformState,
     const std::vector<const RenderLayer*>& layers,
-    const RenderedQueryOptions& options) {
+    const RenderedQueryOptions& options,
+    const CollisionIndex& collisionIndex) {
 
     if (!featureIndex || !data) return;
 
@@ -251,9 +239,10 @@ void GeometryTile::queryRenderedFeatures(
                         std::pow(2, transformState.getZoom() - id.overscaledZ),
                         options,
                         *data,
-                        id.canonical,
+                        id.toUnwrapped(),
+                        sourceID,
                         layers,
-                        collisionTile.get(),
+                        collisionIndex,
                         additionalRadius);
 }
 
@@ -293,11 +282,16 @@ void GeometryTile::querySourceFeatures(
     }
 }
 
-float GeometryTile::yStretch() const {
-    // collisionTile gets reset in onLayout but we don't clear the symbolBuckets
-    // until a new placement result comes along, so keep the yStretch value in
-    // case we need to render them.
-    return lastYStretch;
+void GeometryTile::resetCrossTileIDs() {
+    for (auto& bucket : symbolBuckets) {
+        auto symbolBucket = dynamic_cast<SymbolBucket*>(bucket.second.get());
+        if (symbolBucket && symbolBucket->bucketInstanceId) {
+            symbolBucket->bucketInstanceId = 0;
+            for (auto& symbolInstance : symbolBucket->symbolInstances) {
+                symbolInstance.crossTileID = 0;
+            }
+        }
+    }
 }
 
 } // namespace mbgl
diff --git a/src/mbgl/tile/geometry_tile.hpp b/src/mbgl/tile/geometry_tile.hpp
index a478aad504..3f4b36984b 100644
--- a/src/mbgl/tile/geometry_tile.hpp
+++ b/src/mbgl/tile/geometry_tile.hpp
@@ -4,12 +4,11 @@
 #include <mbgl/tile/geometry_tile_worker.hpp>
 #include <mbgl/renderer/image_manager.hpp>
 #include <mbgl/text/glyph_manager.hpp>
-#include <mbgl/text/placement_config.hpp>
-#include <mbgl/text/collision_tile.hpp>
 #include <mbgl/util/feature.hpp>
 #include <mbgl/util/throttler.hpp>
 #include <mbgl/actor/actor.hpp>
 #include <mbgl/geometry/feature_index.hpp>
+#include <mbgl/layout/symbol_layout.hpp>
 
 #include <atomic>
 #include <memory>
@@ -36,9 +35,9 @@ public:
     void setError(std::exception_ptr);
     void setData(std::unique_ptr<const GeometryTileData>);
 
-    void setPlacementConfig(const PlacementConfig&) override;
     void setLayers(const std::vector<Immutable<style::Layer::Impl>>&) override;
-    
+    void setShowCollisionBoxes(const bool showCollisionBoxes) override;
+
     void onGlyphsAvailable(GlyphMap) override;
     void onImagesAvailable(ImageMap, uint64_t imageCorrelationID) override;
     
@@ -56,7 +55,8 @@ public:
             const GeometryCoordinates& queryGeometry,
             const TransformState&,
             const std::vector<const RenderLayer*>& layers,
-            const RenderedQueryOptions& options) override;
+            const RenderedQueryOptions& options,
+            const CollisionIndex& collisionIndex) override;
 
     void querySourceFeatures(
         std::vector<Feature>& result,
@@ -82,16 +82,13 @@ public:
     class PlacementResult {
     public:
         std::unordered_map<std::string, std::shared_ptr<Bucket>> symbolBuckets;
-        std::unique_ptr<CollisionTile> collisionTile;
         optional<AlphaImage> glyphAtlasImage;
         optional<PremultipliedImage> iconAtlasImage;
 
         PlacementResult(std::unordered_map<std::string, std::shared_ptr<Bucket>> symbolBuckets_,
-                        std::unique_ptr<CollisionTile> collisionTile_,
                         optional<AlphaImage> glyphAtlasImage_,
                         optional<PremultipliedImage> iconAtlasImage_)
             : symbolBuckets(std::move(symbolBuckets_)),
-              collisionTile(std::move(collisionTile_)),
               glyphAtlasImage(std::move(glyphAtlasImage_)),
               iconAtlasImage(std::move(iconAtlasImage_)) {}
     };
@@ -99,7 +96,7 @@ public:
 
     void onError(std::exception_ptr, uint64_t correlationID);
     
-    float yStretch() const override;
+    void resetCrossTileIDs() override;
     
 protected:
     const GeometryTileData* getData() {
@@ -108,7 +105,6 @@ protected:
 
 private:
     void markObsolete();
-    void invokePlacement();
 
     const std::string sourceID;
 
@@ -122,7 +118,6 @@ private:
     ImageManager& imageManager;
 
     uint64_t correlationID = 0;
-    optional<PlacementConfig> requestedConfig;
 
     std::unordered_map<std::string, std::shared_ptr<Bucket>> nonSymbolBuckets;
     std::unique_ptr<FeatureIndex> featureIndex;
@@ -132,10 +127,11 @@ private:
     optional<PremultipliedImage> iconAtlasImage;
 
     std::unordered_map<std::string, std::shared_ptr<Bucket>> symbolBuckets;
-    std::unique_ptr<CollisionTile> collisionTile;
+    std::unordered_map<std::string, std::unique_ptr<SymbolLayout>> symbolLayouts;
 
-    float lastYStretch;
     const MapMode mode;
+    
+    bool showCollisionBoxes;
 
 public:
     optional<gl::Texture> glyphAtlasTexture;
diff --git a/src/mbgl/tile/geometry_tile_worker.cpp b/src/mbgl/tile/geometry_tile_worker.cpp
index 50429420c3..969b137c1f 100644
--- a/src/mbgl/tile/geometry_tile_worker.cpp
+++ b/src/mbgl/tile/geometry_tile_worker.cpp
@@ -1,7 +1,6 @@
 #include <mbgl/tile/geometry_tile_worker.hpp>
 #include <mbgl/tile/geometry_tile_data.hpp>
 #include <mbgl/tile/geometry_tile.hpp>
-#include <mbgl/text/collision_tile.hpp>
 #include <mbgl/layout/symbol_layout.hpp>
 #include <mbgl/renderer/bucket_parameters.hpp>
 #include <mbgl/renderer/group_by_layout.hpp>
@@ -24,15 +23,19 @@ using namespace style;
 GeometryTileWorker::GeometryTileWorker(ActorRef<GeometryTileWorker> self_,
                                        ActorRef<GeometryTile> parent_,
                                        OverscaledTileID id_,
+                                       const std::string& sourceID_,
                                        const std::atomic<bool>& obsolete_,
                                        const MapMode mode_,
-                                       const float pixelRatio_)
+                                       const float pixelRatio_,
+                                       const bool showCollisionBoxes_)
     : self(std::move(self_)),
       parent(std::move(parent_)),
       id(std::move(id_)),
+      sourceID(sourceID_),
       obsolete(obsolete_),
       mode(mode_),
-      pixelRatio(pixelRatio_) {
+      pixelRatio(pixelRatio_),
+      showCollisionBoxes(showCollisionBoxes_) {
 }
 
 GeometryTileWorker::~GeometryTileWorker() = default;
@@ -116,9 +119,9 @@ void GeometryTileWorker::setLayers(std::vector<Immutable<Layer::Impl>> layers_,
     }
 }
 
-void GeometryTileWorker::setPlacementConfig(PlacementConfig placementConfig_, uint64_t correlationID_) {
+void GeometryTileWorker::setShowCollisionBoxes(bool showCollisionBoxes_, uint64_t correlationID_) {
     try {
-        placementConfig = std::move(placementConfig_);
+        showCollisionBoxes = showCollisionBoxes_;
         correlationID = correlationID_;
 
         switch (state) {
@@ -372,7 +375,7 @@ bool GeometryTileWorker::hasPendingSymbolDependencies() const {
 }
 
 void GeometryTileWorker::attemptPlacement() {
-    if (!data || !layers || !placementConfig || hasPendingSymbolDependencies()) {
+    if (!data || !layers || hasPendingSymbolDependencies()) {
         return;
     }
     
@@ -392,13 +395,13 @@ void GeometryTileWorker::attemptPlacement() {
             }
 
             symbolLayout->prepare(glyphMap, glyphAtlas.positions,
-                                  imageMap, imageAtlas.positions);
+                                  imageMap, imageAtlas.positions,
+                                  id, sourceID);
         }
 
         symbolLayoutsNeedPreparation = false;
     }
 
-    auto collisionTile = std::make_unique<CollisionTile>(*placementConfig);
     std::unordered_map<std::string, std::shared_ptr<Bucket>> buckets;
 
     for (auto& symbolLayout : symbolLayouts) {
@@ -410,7 +413,7 @@ void GeometryTileWorker::attemptPlacement() {
             continue;
         }
 
-        std::shared_ptr<Bucket> bucket = symbolLayout->place(*collisionTile);
+        std::shared_ptr<Bucket> bucket = symbolLayout->place(showCollisionBoxes);
         for (const auto& pair : symbolLayout->layerPaintProperties) {
             buckets.emplace(pair.first, bucket);
         }
@@ -418,7 +421,6 @@ void GeometryTileWorker::attemptPlacement() {
 
     parent.invoke(&GeometryTile::onPlacement, GeometryTile::PlacementResult {
         std::move(buckets),
-        std::move(collisionTile),
         std::move(glyphAtlasImage),
         std::move(iconAtlasImage),
     }, correlationID);
diff --git a/src/mbgl/tile/geometry_tile_worker.hpp b/src/mbgl/tile/geometry_tile_worker.hpp
index 1425daa7a1..cc86248cec 100644
--- a/src/mbgl/tile/geometry_tile_worker.hpp
+++ b/src/mbgl/tile/geometry_tile_worker.hpp
@@ -4,7 +4,6 @@
 #include <mbgl/tile/tile_id.hpp>
 #include <mbgl/style/image_impl.hpp>
 #include <mbgl/text/glyph.hpp>
-#include <mbgl/text/placement_config.hpp>
 #include <mbgl/actor/actor_ref.hpp>
 #include <mbgl/util/optional.hpp>
 #include <mbgl/util/immutable.hpp>
@@ -28,14 +27,16 @@ public:
     GeometryTileWorker(ActorRef<GeometryTileWorker> self,
                        ActorRef<GeometryTile> parent,
                        OverscaledTileID,
+                       const std::string&,
                        const std::atomic<bool>&,
                        const MapMode,
-                       const float pixelRatio);
+                       const float pixelRatio,
+                       const bool showCollisionBoxes_);
     ~GeometryTileWorker();
 
     void setLayers(std::vector<Immutable<style::Layer::Impl>>, uint64_t correlationID);
     void setData(std::unique_ptr<const GeometryTileData>, uint64_t correlationID);
-    void setPlacementConfig(PlacementConfig, uint64_t correlationID);
+    void setShowCollisionBoxes(bool showCollisionBoxes_, uint64_t correlationID_);
     
     void onGlyphsAvailable(GlyphMap glyphs);
     void onImagesAvailable(ImageMap images, uint64_t imageCorrelationID);
@@ -57,6 +58,7 @@ private:
     ActorRef<GeometryTile> parent;
 
     const OverscaledTileID id;
+    const std::string sourceID;
     const std::atomic<bool>& obsolete;
     const MapMode mode;
     const float pixelRatio;
@@ -75,7 +77,6 @@ private:
     // Outer optional indicates whether we've received it or not.
     optional<std::vector<Immutable<style::Layer::Impl>>> layers;
     optional<std::unique_ptr<const GeometryTileData>> data;
-    optional<PlacementConfig> placementConfig;
 
     bool symbolLayoutsNeedPreparation = false;
     std::vector<std::unique_ptr<SymbolLayout>> symbolLayouts;
@@ -83,6 +84,8 @@ private:
     ImageDependencies pendingImageDependencies;
     GlyphMap glyphMap;
     ImageMap imageMap;
+    
+    bool showCollisionBoxes;
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/tile/tile.hpp b/src/mbgl/tile/tile.hpp
index 8be7c4d862..65a497aaae 100644
--- a/src/mbgl/tile/tile.hpp
+++ b/src/mbgl/tile/tile.hpp
@@ -23,7 +23,6 @@ namespace mbgl {
 class DebugBucket;
 class TransformState;
 class TileObserver;
-class PlacementConfig;
 class RenderLayer;
 class RenderedQueryOptions;
 class SourceQueryOptions;
@@ -47,7 +46,7 @@ public:
     virtual void upload(gl::Context&) = 0;
     virtual Bucket* getBucket(const style::Layer::Impl&) const = 0;
 
-    virtual void setPlacementConfig(const PlacementConfig&) {}
+    virtual void setShowCollisionBoxes(const bool) {}
     virtual void setLayers(const std::vector<Immutable<style::Layer::Impl>>&) {}
     virtual void setMask(TileMask&&) {}
 
@@ -92,6 +91,8 @@ public:
     bool isComplete() const {
         return loaded && !pending;
     }
+    
+    virtual void resetCrossTileIDs() {};
 
     void dumpDebugLogs() const;
 
@@ -101,8 +102,6 @@ public:
 
     // Contains the tile ID string for painting debug information.
     std::unique_ptr<DebugBucket> debugBucket;
-    
-    virtual float yStretch() const { return 1.0f; }
 
 protected:
     bool triedOptional = false;