gles 3 shaders

data/ofxMsdfgen/shaders/simple/ES3/shader.frag

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+#version 300 es
+precision highp float;
+
+// these are our textures
+uniform sampler2D msdf;
+
+uniform vec4 fontColor;
+uniform float pxRange;
+
+// this comes from the vertex shader
+in vec2 texCoordVarying;
+out vec4 outputColor;
+
+float median(float r, float g, float b) {
+    return max(min(r, g), min(max(r, g), b));
+}
+
+float screenPxRange() {
+    ivec2 ts = textureSize(msdf, 0);
+    vec2 unitRange = vec2(pxRange)/vec2(ts);
+    vec2 screenTexSize = vec2(1.0)/fwidth(texCoordVarying);
+    return max(0.5*dot(unitRange, screenTexSize), 1.0);
+}
+
+void main()
+{
+    vec4 bgColor = vec4(fontColor.rgb,0);
+    vec4 fgColor = fontColor;
+
+    vec3 msdf_rgb = texture(msdf, texCoordVarying).rgb;
+    float sd = median(msdf_rgb.r, msdf_rgb.g, msdf_rgb.b);
+    float screenPxDistance = screenPxRange()*(sd - 0.5);
+    float opacity = clamp(screenPxDistance + 0.5, 0.0, 1.0);
+    outputColor = mix(bgColor, fgColor, opacity);
+}

data/ofxMsdfgen/shaders/simple/ES3/shader.vert

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+#version 300 es
+
+// whoops these are for the programmable pipeline system
+uniform mat4 modelViewProjectionMatrix;
+
+in vec4 position;
+in vec2 texcoord;
+
+out vec2 texCoordVarying;
+
+void main()
+{
+    texCoordVarying = texcoord;
+    gl_Position = modelViewProjectionMatrix * position;
+}