Line texture: fix fragment shader, #105

mapsforge · Aug 7, 2016 · a4934a5 · a4934a5
1 parent c926a71
commit a4934a5
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Showing 2 changed files with 23 additions and 4 deletions.
diff --git a/vtm/resources/assets/shaders/linetex_layer_tex.glsl b/vtm/resources/assets/shaders/linetex_layer_tex.glsl
@@ -38,9 +38,25 @@ uniform vec4 u_bgcolor;
 uniform float u_pwidth;
 varying vec2 v_st;
 uniform sampler2D tex;
+uniform float u_mode;
 void
 main(){
-  vec4 c=texture2D(tex,vec2(abs(mod(v_st.s+1.0,2.0)),(v_st.t+1.0)*0.5));
-  float fuzz=fwidth(c.a);
-  gl_FragColor=(c * u_color) *smoothstep(0.5-fuzz,0.5+fuzz,c.a);
+  if (u_mode == 1.0) {
+    vec4 c=texture2D(tex,vec2(abs(mod(v_st.s+1.0,2.0)),(v_st.t+1.0)*0.5));
+    float fuzz=fwidth(c.a);
+    gl_FragColor=(c * u_color) *smoothstep(0.5-fuzz,0.5+fuzz,c.a);
+  }
+  else {
+    /* distance on perpendicular to the line */
+    float dist = abs(v_st.t);
+    float fuzz = fwidth(v_st.t);
+    float fuzz_p = fwidth(v_st.s);
+    float line_w = smoothstep(0.0, fuzz, 1.0 - dist);
+    float stipple_w = smoothstep(0.0, fuzz, u_pwidth - dist);
+    /* triangle waveform in the range 0..1 for regular pattern */
+    float phase = abs(mod(v_st.s, 2.0) - 1.0);
+    /* interpolate between on/off phase, 0.5 = equal phase length */
+    float stipple_p = smoothstep(0.5 - fuzz_p, 0.5 + fuzz_p, phase);
+    gl_FragColor = line_w * mix(u_bgcolor, u_color, min(stipple_w, stipple_p));
+  }
 }
diff --git a/vtm/src/org/oscim/renderer/bucket/LineTexBucket.java b/vtm/src/org/oscim/renderer/bucket/LineTexBucket.java
@@ -217,7 +217,7 @@ protected void compile(ShortBuffer vboData, ShortBuffer iboData) {
     }
 
     static class Shader extends GLShader {
-        int uMVP, uColor, uWidth, uBgColor, uScale;
+        int uMVP, uColor, uWidth, uBgColor, uScale, uMode;
         int uPatternWidth, uPatternScale;
         int aPos0, aPos1, aLen0, aLen1, aFlip;
 
@@ -231,6 +231,7 @@ static class Shader extends GLShader {
             uColor = getUniform("u_color");
             uWidth = getUniform("u_width");
             uBgColor = getUniform("u_bgcolor");
+            uMode = getUniform("u_mode");
 
             uPatternWidth = getUniform("u_pwidth");
             uPatternScale = getUniform("u_pscale");
@@ -360,6 +361,8 @@ public static RenderBucket draw(RenderBucket b, GLViewport v,
                 LineTexBucket lb = (LineTexBucket) b;
                 LineStyle line = lb.line.current();
 
+                gl.uniform1f(shader.uMode, line.texture != null ? 1 : 0);
+
                 if (line.texture != null)
                     line.texture.bind();