From 3d960c8136541f1f6d71409e23b8f56eee9dd1d0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Konstantin=20K=C3=A4fer?= <mail@kkaefer.com>
Date: Tue, 6 Sep 2016 14:38:49 +0200
Subject: [PATCH] [core] change bool round to LinePatternCap

---
 src/mbgl/geometry/line_atlas.cpp   | 14 ++++++++------
 src/mbgl/geometry/line_atlas.hpp   |  9 +++++++--
 src/mbgl/renderer/painter_line.cpp |  6 ++++--
 3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/src/mbgl/geometry/line_atlas.cpp b/src/mbgl/geometry/line_atlas.cpp
index f08ea1e5f..bc81c38f5 100644
--- a/src/mbgl/geometry/line_atlas.cpp
+++ b/src/mbgl/geometry/line_atlas.cpp
@@ -21,8 +21,10 @@ LineAtlas::LineAtlas(GLsizei w, GLsizei h)
 
 LineAtlas::~LineAtlas() = default;
 
-LinePatternPos LineAtlas::getDashPosition(const std::vector<float>& dasharray, bool round) {
-    size_t key = round ? std::numeric_limits<size_t>::min() : std::numeric_limits<size_t>::max();
+LinePatternPos LineAtlas::getDashPosition(const std::vector<float>& dasharray,
+                                          LinePatternCap patternCap) {
+    size_t key = patternCap == LinePatternCap::Round ? std::numeric_limits<size_t>::min()
+                                                     : std::numeric_limits<size_t>::max();
     for (const float part : dasharray) {
         boost::hash_combine<float>(key, part);
     }
@@ -30,7 +32,7 @@ LinePatternPos LineAtlas::getDashPosition(const std::vector<float>& dasharray, b
     // Note: We're not handling hash collisions here.
     const auto it = positions.find(key);
     if (it == positions.end()) {
-        auto inserted = positions.emplace(key, addDash(dasharray, round));
+        auto inserted = positions.emplace(key, addDash(dasharray, patternCap));
         assert(inserted.second);
         return inserted.first->second;
     } else {
@@ -38,8 +40,8 @@ LinePatternPos LineAtlas::getDashPosition(const std::vector<float>& dasharray, b
     }
 }
 
-LinePatternPos LineAtlas::addDash(const std::vector<float>& dasharray, bool round) {
-    int n = round ? 7 : 0;
+LinePatternPos LineAtlas::addDash(const std::vector<float>& dasharray, LinePatternCap patternCap) {
+    int n = patternCap == LinePatternCap::Round ? 7 : 0;
     int dashheight = 2 * n + 1;
     const uint8_t offset = 128;
 
@@ -90,7 +92,7 @@ LinePatternPos LineAtlas::addDash(const std::vector<float>& dasharray, bool roun
             bool inside = (partIndex % 2) == 1;
             int signedDistance;
 
-            if (round) {
+            if (patternCap == LinePatternCap::Round) {
                 float distMiddle = n ? (float)y / n * (halfWidth + 1) : 0;
                 if (inside) {
                     float distEdge = halfWidth - fabs(distMiddle);
diff --git a/src/mbgl/geometry/line_atlas.hpp b/src/mbgl/geometry/line_atlas.hpp
index 1e6c0ac84..a2bda7186 100644
--- a/src/mbgl/geometry/line_atlas.hpp
+++ b/src/mbgl/geometry/line_atlas.hpp
@@ -19,6 +19,11 @@ typedef struct {
     float y;
 } LinePatternPos;
 
+enum class LinePatternCap : bool {
+    Square = false,
+    Round = true,
+};
+
 class LineAtlas {
 public:
     LineAtlas(GLsizei width, GLsizei height);
@@ -31,8 +36,8 @@ public:
     // the texture is only bound when the data is out of date (=dirty).
     void upload(gl::ObjectStore&, gl::Config&, uint32_t unit);
 
-    LinePatternPos getDashPosition(const std::vector<float>&, bool);
-    LinePatternPos addDash(const std::vector<float>& dasharray, bool round);
+    LinePatternPos getDashPosition(const std::vector<float>&, LinePatternCap);
+    LinePatternPos addDash(const std::vector<float>& dasharray, LinePatternCap);
 
     const GLsizei width;
     const GLsizei height;
diff --git a/src/mbgl/renderer/painter_line.cpp b/src/mbgl/renderer/painter_line.cpp
index 2702440d2..f6afaa7ec 100644
--- a/src/mbgl/renderer/painter_line.cpp
+++ b/src/mbgl/renderer/painter_line.cpp
@@ -72,8 +72,10 @@ void Painter::renderLine(PaintParameters& parameters,
         linesdfShader.u_color = color;
         linesdfShader.u_opacity = opacity;
 
-        LinePatternPos posA = lineAtlas->getDashPosition(properties.lineDasharray.value.from, layout.lineCap == LineCapType::Round);
-        LinePatternPos posB = lineAtlas->getDashPosition(properties.lineDasharray.value.to, layout.lineCap == LineCapType::Round);
+        const LinePatternCap cap =
+            layout.lineCap == LineCapType::Round ? LinePatternCap::Round : LinePatternCap::Square;
+        LinePatternPos posA = lineAtlas->getDashPosition(properties.lineDasharray.value.from, cap);
+        LinePatternPos posB = lineAtlas->getDashPosition(properties.lineDasharray.value.to, cap);
 
         const float widthA = posA.width * properties.lineDasharray.value.fromScale * layer.impl->dashLineWidth;
         const float widthB = posB.width * properties.lineDasharray.value.toScale * layer.impl->dashLineWidth;