Less fading for line labels.

2 files changed, 14 insertions, 11 deletions

diff --git a/src/mbgl/text/placement.cpp b/src/mbgl/text/placement.cpp
index 85f6385ce6..112d641be0 100644
--- a/src/mbgl/text/placement.cpp
+++ b/src/mbgl/text/placement.cpp
@@ -8,8 +8,8 @@
 
 namespace mbgl {
 
-OpacityState::OpacityState(bool placed_, bool offscreen)
-    : opacity((offscreen && placed_) ? 1 : 0)
+OpacityState::OpacityState(bool placed_, bool skipFadeIn)
+    : opacity((skipFadeIn && placed_) ? 1 : 0)
     , placed(placed_)
 {
 }
@@ -22,9 +22,9 @@ bool OpacityState::isHidden() const {
     return opacity == 0 && !placed;
 }
 
-JointOpacityState::JointOpacityState(bool placedIcon, bool placedText, bool offscreen) :
-    icon(OpacityState(placedIcon, offscreen)),
-    text(OpacityState(placedText, offscreen)) {}
+JointOpacityState::JointOpacityState(bool placedIcon, bool placedText, bool skipFadeIn) :
+    icon(OpacityState(placedIcon, skipFadeIn)),
+    text(OpacityState(placedText, skipFadeIn)) {}
 
 JointOpacityState::JointOpacityState(const JointOpacityState& prevOpacityState, float increment, bool placedIcon, bool placedText) :
     icon(OpacityState(prevOpacityState.icon, increment, placedIcon)),
@@ -104,6 +104,7 @@ void Placement::placeLayerBucket(
             bool placeText = false;
             bool placeIcon = false;
             bool offscreen = true;
+            bool lineLabel = false;
 
             if (symbolInstance.placedTextIndex) {
                 PlacedSymbol& placedSymbol = bucket.text.placedSymbols.at(*symbolInstance.placedTextIndex);
@@ -117,6 +118,7 @@ void Placement::placeLayerBucket(
                         showCollisionBoxes);
                 placeText = placed.first;
                 offscreen &= placed.second;
+                lineLabel = symbolInstance.textCollisionFeature.alongLine;
             }
 
             if (symbolInstance.placedIconIndex) {
@@ -152,7 +154,7 @@ void Placement::placeLayerBucket(
 
             assert(symbolInstance.crossTileID != 0);
 
-            placements.emplace(symbolInstance.crossTileID, JointPlacement(placeText, placeIcon, offscreen));
+            placements.emplace(symbolInstance.crossTileID, JointPlacement(placeText, placeIcon, offscreen, lineLabel));
             seenCrossTileIDs.insert(symbolInstance.crossTileID);
         }
     } 
@@ -164,7 +166,7 @@ bool Placement::commit(const Placement& prevPlacement, TimePoint now) {
     bool placementChanged = false;
 
     float increment = mapMode == MapMode::Continuous ?
-        std::chrono::duration<float>(commitTime - prevPlacement.commitTime) / Duration(std::chrono::milliseconds(300)) :
+        std::chrono::duration<float>(commitTime - prevPlacement.commitTime) / Duration(std::chrono::milliseconds(2000)) :
         1.0;
 
     // add the opacities from the current placement, and copy their current values from the previous placement
@@ -176,7 +178,7 @@ bool Placement::commit(const Placement& prevPlacement, TimePoint now) {
                 jointPlacement.second.icon != prevOpacity->second.icon.placed ||
                 jointPlacement.second.text != prevOpacity->second.text.placed;
         } else {
-            opacities.emplace(jointPlacement.first, JointOpacityState(jointPlacement.second.icon, jointPlacement.second.text, jointPlacement.second.offscreen));
+            opacities.emplace(jointPlacement.first, JointOpacityState(jointPlacement.second.icon, jointPlacement.second.text, jointPlacement.second.offscreen || jointPlacement.second.lineLabel));
             placementChanged = placementChanged || jointPlacement.second.icon || jointPlacement.second.text;
         }
     }
@@ -287,7 +289,7 @@ JointOpacityState Placement::getOpacity(uint32_t crossTileSymbolID) const {
 
 float Placement::symbolFadeChange(TimePoint now) const {
     if (mapMode == MapMode::Continuous) {
-        return std::chrono::duration<float>(now - commitTime) / Duration(std::chrono::milliseconds(300));
+        return std::chrono::duration<float>(now - commitTime) / Duration(std::chrono::milliseconds(2000));
     } else {
         return 1.0;
     }
diff --git a/src/mbgl/text/placement.hpp b/src/mbgl/text/placement.hpp
index c6d1f259a5..68de16a358 100644
--- a/src/mbgl/text/placement.hpp
+++ b/src/mbgl/text/placement.hpp
@@ -32,8 +32,8 @@ public:
 
 class JointPlacement {
 public:
-    JointPlacement(bool text_, bool icon_, bool offscreen_)
-        : text(text_), icon(icon_), offscreen(offscreen_)
+    JointPlacement(bool text_, bool icon_, bool offscreen_, bool lineLabel_)
+        : text(text_), icon(icon_), offscreen(offscreen_), lineLabel(lineLabel_)
     {}
 
     const bool text;
@@ -43,6 +43,7 @@ public:
     // and if a subsequent viewport change brings them into view, they'll be fully
     // visible right away.
     const bool offscreen;
+    const bool lineLabel;
 };
 
 class Placement {