tei/MapLibreParticleLab
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[core][tile mode] Improve placement algorithm for variable labels

Browse Source
This commit is contained in:
Mikhail Pozdnyakov
2020-04-06 16:56:57 +03:00
parent 8165b7dee1
commit 88337c23f7
2 changed files with 26 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
src/mbgl/text/placement.cpp
View File

@@ -390,7 +390,6 @@ void Placement::placeSymbol(const SymbolInstance& symbolInstance,
const size_t placementAttempts = ctx.textAllowOverlap ? anchorsSize * 2 : anchorsSize;
for (size_t i = 0u; i < placementAttempts; ++i) {
auto anchor = variableTextAnchors[i % anchorsSize];
const bool isFirstAnchor = (anchor == variableTextAnchors.front());
const bool allowOverlap = (i >= anchorsSize);
shift = calculateVariableLayoutOffset(anchor,
width,
@@ -401,9 +400,8 @@ void Placement::placeSymbol(const SymbolInstance& symbolInstance,
ctx.pitchTextWithMap,
ctx.getTransformState().getBearing());
textBoxes.clear();
if (!isFirstAnchor &&
stickToFirstVariableAnchor(
symbolInstance.textCollisionFeature.boxes.front(), shift, posMatrix, ctx.pixelRatio)) {
if (!canPlaceAtVariableAnchor(
textBox, anchor, shift, variableTextAnchors, posMatrix, ctx.pixelRatio)) {
continue;
}
@@ -1263,10 +1261,12 @@ private:
const std::vector<PlacedSymbolData>& getPlacedSymbolsData() const override { return placedSymbolsData; }
optional<CollisionBoundaries> getAvoidEdges(const SymbolBucket&, const mat4&) override;
bool stickToFirstVariableAnchor(const CollisionBox& box,
Point<float> shift,
const mat4& posMatrix,
float textPixelRatio) override;
bool canPlaceAtVariableAnchor(const CollisionBox& box,
TextVariableAnchorType anchor,
Point<float> shift,
std::vector<style::TextVariableAnchorType>& anchors,
const mat4& posMatrix,
float textPixelRatio) override;
void newSymbolPlaced(const SymbolInstance&,
const JointPlacement&,
style::SymbolPlacementType,
@@ -1438,12 +1438,19 @@ void TilePlacement::placeSymbolBucket(const BucketPlacementData& params, std::se
}
}
bool TilePlacement::stickToFirstVariableAnchor(const CollisionBox& box,
Point<float> shift,
const mat4& posMatrix,
float textPixelRatio) {
bool TilePlacement::canPlaceAtVariableAnchor(const CollisionBox& box,
TextVariableAnchorType anchor,
Point<float> shift,
std::vector<style::TextVariableAnchorType>& anchors,
const mat4& posMatrix,
float textPixelRatio) {
assert(tileBorders);
auto status = collisionIndex.intersectsTileEdges(box, shift, posMatrix, textPixelRatio, *tileBorders);
if (status.flags == IntersectStatus::None) return true;
if (anchor != anchors.front()) return false;
status = collisionIndex.intersectsTileEdges(box, {}, posMatrix, textPixelRatio, *tileBorders);
return status.flags != IntersectStatus::None;
}

12
src/mbgl/text/placement.hpp
View File

@@ -157,11 +157,13 @@ protected:
return nullopt;
}
SymbolInstanceReferences getSortedSymbols(const BucketPlacementData&, float pixelRatio);
virtual bool stickToFirstVariableAnchor(const CollisionBox&,
Point<float> /*shift*/,
const mat4& /*posMatrix*/,
float /*textPixelRatio*/) {
return false;
virtual bool canPlaceAtVariableAnchor(const CollisionBox&,
style::TextVariableAnchorType,
Point<float> /*shift*/,
std::vector<style::TextVariableAnchorType>&,
const mat4& /*posMatrix*/,
float /*textPixelRatio*/) {
return true;
}
// Returns `true` if bucket vertices were updated; returns `false` otherwise.