diff options
Diffstat (limited to 'src/mbgl/text/placement.cpp')
| -rw-r--r-- | src/mbgl/text/placement.cpp | 91 |
1 files changed, 70 insertions, 21 deletions
diff --git a/src/mbgl/text/placement.cpp b/src/mbgl/text/placement.cpp index 8740e4b021..49c3831d63 100644 --- a/src/mbgl/text/placement.cpp +++ b/src/mbgl/text/placement.cpp @@ -356,8 +356,11 @@ void Placement::placeBucket(const SymbolBucket& bucket, textBoxes.clear(); if (mapMode == MapMode::Tile && !isFirstAnchor && - collisionIndex.featureIntersectsTileBorders( - textCollisionFeature, shift, posMatrix, pixelRatio, *tileBorders)) { + collisionIndex.intercectsTileEdges(symbolInstance.textCollisionFeature.boxes.front(), + shift, + posMatrix, + pixelRatio, + *tileBorders)) { continue; } @@ -561,19 +564,42 @@ void Placement::placeBucket(const SymbolBucket& bucket, } else if (mapMode == MapMode::Tile && !avoidEdges) { // In this case we first try to place symbols, which intersects the tile borders, so that // those symbols will remain even if each tile is handled independently. - const auto& symbolInstances = bucket.symbolInstances; - std::vector<std::reference_wrapper<const SymbolInstance>> sorted(symbolInstances.begin(), - symbolInstances.end()); + std::vector<std::reference_wrapper<const SymbolInstance>> symbolInstances(bucket.symbolInstances.begin(), + bucket.symbolInstances.end()); optional<style::TextVariableAnchorType> variableAnchor; if (!variableTextAnchors.empty()) variableAnchor = variableTextAnchors.front(); - std::unordered_map<uint32_t, bool> sortedCache; - sortedCache.reserve(sorted.size()); - auto intersectsTileBorder = [&](const SymbolInstance& symbol) -> bool { - if (symbol.textCollisionFeature.alongLine || symbol.textCollisionFeature.boxes.empty()) return false; + std::unordered_map<uint32_t, bool> locationCache; + locationCache.reserve(symbolInstances.size()); - auto it = sortedCache.find(symbol.crossTileID); - if (it != sortedCache.end()) return it->second; + // Keeps the data necessary to find a feature location according to a tile. + struct NeighborTileData { + NeighborTileData(const CollisionIndex& collisionIndex, UnwrappedTileID id_, Point<float> shift_) + : id(id_), shift(shift_), matrix() { + collisionIndex.getTransformState().matrixFor(matrix, id); + matrix::multiply(matrix, collisionIndex.getTransformState().getProjectionMatrix(), matrix); + borders = collisionIndex.projectTileBoundaries(matrix); + } + + UnwrappedTileID id; + Point<float> shift; + mat4 matrix; + CollisionBoundaries borders; + }; + + uint8_t z = renderTile.id.canonical.z; + uint32_t x = renderTile.id.canonical.x; + uint32_t y = renderTile.id.canonical.y; + const std::array<NeighborTileData, 4> neightbors{{ + {collisionIndex, UnwrappedTileID(z, x, y - 1), {0.0f, util::EXTENT}}, // top + {collisionIndex, UnwrappedTileID(z, x, y + 1), {0.0f, -util::EXTENT}}, // bottom + {collisionIndex, UnwrappedTileID(z, x - 1, y), {util::EXTENT, 0.0f}}, // left + {collisionIndex, UnwrappedTileID(z, x + 1, y), {-util::EXTENT, 0.0f}} // right + }}; + + auto intercectsTileEdges = [&](const CollisionBox& collisionBox, const SymbolInstance& symbol) -> bool { + auto it = locationCache.find(symbol.crossTileID); + if (it != locationCache.end()) return it->second; Point<float> offset{}; if (variableAnchor) { @@ -589,18 +615,41 @@ void Placement::placeBucket(const SymbolBucket& bucket, pitchTextWithMap, state.getBearing()); } - bool result = collisionIndex.featureIntersectsTileBorders( - symbol.textCollisionFeature, offset, posMatrix, pixelRatio, *tileBorders); - sortedCache.insert(std::make_pair(symbol.crossTileID, result)); - return result; - }; - std::stable_sort( - sorted.begin(), sorted.end(), [&intersectsTileBorder](const SymbolInstance& a, const SymbolInstance& b) { - return intersectsTileBorder(a) && !intersectsTileBorder(b); - }); + bool intercects = + collisionIndex.intercectsTileEdges(collisionBox, offset, renderTile.matrix, pixelRatio, *tileBorders); + if (!intercects) { + // Check if this symbol intersects the neighbor tile borders. + // If so, it also shall be placed with priority (location = FeatureLocation::IntersectsTileBorder). + for (const auto& neighbor : neightbors) { + intercects = collisionIndex.intercectsTileEdges( + collisionBox, offset + neighbor.shift, neighbor.matrix, pixelRatio, neighbor.borders); + if (intercects) break; + } + } + + locationCache.insert(std::make_pair(symbol.crossTileID, intercects)); + return intercects; + }; - for (const SymbolInstance& symbol : sorted) { + std::stable_sort(symbolInstances.begin(), + symbolInstances.end(), + [&intercectsTileEdges](const SymbolInstance& a, const SymbolInstance& b) { + if (a.textCollisionFeature.alongLine || a.textCollisionFeature.boxes.empty()) return false; + if (b.textCollisionFeature.alongLine || b.textCollisionFeature.boxes.empty()) return false; + + auto intercectsA = intercectsTileEdges(a.textCollisionFeature.boxes.front(), a); + auto intercectsB = intercectsTileEdges(b.textCollisionFeature.boxes.front(), b); + if (intercectsA) { + if (!intercectsB) return true; + // Both symbols are inrecepting the tile borders, we need a universal cross-tile rule + // to define which of them shall be placed first - use anchor `y` point. + return a.anchor.point.y < b.anchor.point.y; + } + return false; + }); + + for (const SymbolInstance& symbol : symbolInstances) { placeSymbol(symbol); } |