diff --git a/demo2/cover.fs.glsl b/demo2/cover.fs.glsl
index 0deaafdc..e2c851bc 100644
--- a/demo2/cover.fs.glsl
+++ b/demo2/cover.fs.glsl
@@ -15,11 +15,12 @@ precision highp float;
uniform sampler2D uStencilTexture;
in vec2 vTexCoord;
+in float vBackdrop;
in vec4 vColor;
out vec4 oFragColor;
void main() {
- float coverage = abs(texture(uStencilTexture, vTexCoord).r);
+ float coverage = abs(texture(uStencilTexture, vTexCoord).r + vBackdrop);
oFragColor = vec4(vColor.rgb, vColor.a * coverage);
}
diff --git a/demo2/cover.vs.glsl b/demo2/cover.vs.glsl
index 49722b0f..dafad025 100644
--- a/demo2/cover.vs.glsl
+++ b/demo2/cover.vs.glsl
@@ -18,10 +18,12 @@ uniform vec2 uStencilTextureSize;
in vec2 aTessCoord;
in vec2 aTileOrigin;
+in float aBackdrop;
in uint aTileIndex;
in vec4 aColor;
out vec2 vTexCoord;
+out float vBackdrop;
out vec4 vColor;
vec2 computeTileOffset(uint tileIndex, float stencilTextureWidth) {
@@ -34,6 +36,7 @@ void main() {
vec2 position = aTileOrigin + uTileSize * aTessCoord;
vec2 texCoord = computeTileOffset(aTileIndex, uStencilTextureSize.x) + aTessCoord * uTileSize;
vTexCoord = texCoord / uStencilTextureSize;
+ vBackdrop = aBackdrop;
vColor = aColor;
gl_Position = vec4((position / uFramebufferSize * 2.0 - 1.0) * vec2(1.0, -1.0), 0.0, 1.0);
}
diff --git a/demo2/index.html b/demo2/index.html
index 5510ca0c..78fa63d6 100644
--- a/demo2/index.html
+++ b/demo2/index.html
@@ -5,10 +5,13 @@
Pathfinder Demo
-
+
+