Fixed traffic rendering

6 files changed, 67 insertions, 2 deletions

diff --git a/shaders/CMakeLists.txt b/shaders/CMakeLists.txt
index 1a61cfbaa2..2c65193980 100644
--- a/shaders/CMakeLists.txt
+++ b/shaders/CMakeLists.txt
@@ -96,6 +96,8 @@ set(
   GL/texturing_gui.vsh.glsl
   GL/traffic.fsh.glsl
   GL/traffic.vsh.glsl
+  GL/traffic_circle.fsh.glsl
+  GL/traffic_circle.vsh.glsl
   GL/traffic_line.fsh.glsl
   GL/traffic_line.vsh.glsl
   GL/transit.fsh.glsl
diff --git a/shaders/GL/shader_index.txt b/shaders/GL/shader_index.txt
index 26b82eb11a..2514ad6075 100644
--- a/shaders/GL/shader_index.txt
+++ b/shaders/GL/shader_index.txt
@@ -43,6 +43,7 @@ TextBillboard text_billboard.vsh.glsl text.fsh.glsl
 TextFixedBillboard text_billboard.vsh.glsl text_fixed.fsh.glsl
 Traffic traffic.vsh.glsl traffic.fsh.glsl
 TrafficLine traffic_line.vsh.glsl traffic_line.fsh.glsl
+TrafficCircle traffic_circle.vsh.glsl traffic_circle.fsh.glsl
 SmaaEdges smaa_edges.vsh.glsl smaa_edges.fsh.glsl
 SmaaBlendingWeight smaa_blending_weight.vsh.glsl smaa_blending_weight.fsh.glsl
 SmaaFinal smaa_final.vsh.glsl smaa_final.fsh.glsl
diff --git a/shaders/GL/traffic_circle.fsh.glsl b/shaders/GL/traffic_circle.fsh.glsl
new file mode 100644
index 0000000000..e26402112d
--- /dev/null
+++ b/shaders/GL/traffic_circle.fsh.glsl
@@ -0,0 +1,23 @@
+// Warning! Beware to use this shader. "discard" command may significally reduce performance.
+// Unfortunately some CG algorithms cannot be implemented on OpenGL ES 2.0 without discarding
+// fragments from depth buffer.
+
+varying vec2 v_colorTexCoord;
+varying vec3 v_radius;
+
+uniform sampler2D u_colorTex;
+uniform float u_opacity;
+
+const float kAntialiasingThreshold = 0.92;
+
+void main()
+{
+  vec4 color = texture2D(u_colorTex, v_colorTexCoord);
+  float smallRadius = v_radius.z * kAntialiasingThreshold;
+  float stepValue = smoothstep(smallRadius * smallRadius, v_radius.z * v_radius.z,
+                               v_radius.x * v_radius.x + v_radius.y * v_radius.y);
+  color.a = u_opacity * (1.0 - stepValue);
+  if (color.a < 0.01)
+    discard;
+  gl_FragColor = color;
+}
diff --git a/shaders/GL/traffic_circle.vsh.glsl b/shaders/GL/traffic_circle.vsh.glsl
new file mode 100644
index 0000000000..914f0ba838
--- /dev/null
+++ b/shaders/GL/traffic_circle.vsh.glsl
@@ -0,0 +1,36 @@
+attribute vec4 a_position;
+attribute vec4 a_normal;
+attribute vec2 a_colorTexCoord;
+
+uniform mat4 u_modelView;
+uniform mat4 u_projection;
+uniform mat4 u_pivotTransform;
+
+uniform vec3 u_lightArrowColor; // Here we store left sizes by road classes.
+uniform vec3 u_darkArrowColor; // Here we store right sizes by road classes.
+
+varying vec2 v_colorTexCoord;
+varying vec3 v_radius;
+
+void main()
+{
+  vec2 normal = a_normal.xy;
+  vec2 transformedAxisPos = (vec4(a_position.xy, 0.0, 1.0) * u_modelView).xy;
+  int index = int(a_position.w);
+  float leftSize = u_lightArrowColor[index];
+  float rightSize = u_darkArrowColor[index];
+  if (dot(normal, normal) != 0.0)
+  {
+    // offset by normal = rightVec * (rightSize - leftSize) / 2
+    vec2 norm = normal * 0.5 * (rightSize - leftSize);
+    transformedAxisPos = calcLineTransformedAxisPos(transformedAxisPos, a_position.xy + norm,
+                                                    u_modelView, length(norm));
+  }
+  // radius = (leftSize + rightSize) / 2
+  v_radius = vec3(a_normal.zw, 1.0) * 0.5 * (leftSize + rightSize);
+
+  vec2 finalPos = transformedAxisPos + v_radius.xy;
+  v_colorTexCoord = a_colorTexCoord;
+  vec4 pos = vec4(finalPos, a_position.z, 1.0) * u_projection;
+  gl_Position = applyPivotTransform(pos, u_pivotTransform, 0.0);
+}
diff --git a/shaders/program_params.hpp b/shaders/program_params.hpp
index 4dd1077bff..3ea1478c90 100644
--- a/shaders/program_params.hpp
+++ b/shaders/program_params.hpp
@@ -118,7 +118,8 @@ struct TrafficProgramParams
 
   BIND_PROGRAMS(TrafficProgramParams,
     Program::Traffic,
-    Program::TrafficLine)
+    Program::TrafficLine,
+    Program::TrafficCircle)
 };
 
 struct TransitProgramParams
@@ -163,7 +164,7 @@ struct ShapesProgramParams
   float m_opacity = 1.0f;
   float m_azimut = 0.0;
 
-  BIND_PROGRAMS(AccuracyProgramParams,
+  BIND_PROGRAMS(ShapesProgramParams,
     Program::Accuracy,
     Program::MyPosition)
 };
diff --git a/shaders/programs.hpp b/shaders/programs.hpp
index 1a5379b141..0510369343 100644
--- a/shaders/programs.hpp
+++ b/shaders/programs.hpp
@@ -54,6 +54,7 @@ enum class Program
   TextFixedBillboard,
   Traffic,
   TrafficLine,
+  TrafficCircle,
   SmaaEdges,
   SmaaBlendingWeight,
   SmaaFinal,
@@ -110,6 +111,7 @@ inline std::string DebugPrint(Program p)
   case Program::TextFixedBillboard: return "TextFixedBillboard";
   case Program::Traffic: return "Traffic";
   case Program::TrafficLine: return "TrafficLine";
+  case Program::TrafficCircle: return "TrafficCircle";
   case Program::SmaaEdges: return "SmaaEdges";
   case Program::SmaaBlendingWeight: return "SmaaBlendingWeight";
   case Program::SmaaFinal: return "SmaaFinal";