Updated the shader *.fx files to XNA 4, as per Shawn Hargreaves suggestion of using the Bloom sample. First attempt at porting these shaders to GLSL.

StarterKits/MacOS/VectorRumble/Content/Effects/BloomCombine.fsh

@@ -1 +1,35 @@
+uniform sampler2D BloomSampler;
+uniform sampler2D BaseSampler;
 
+uniform vec2 float BloomIntensity;
+uniform vec2 float BaseIntensity;
+
+uniform vec2 float BloomSaturation;
+uniform vec2 float BaseSaturation;
+
+// Helper for modifying the saturation of a color.
+vec4 AdjustSaturation(vec4 color, vec saturation)
+{
+    // The constants 0.3, 0.59, and 0.11 are chosen because the
+    // human eye is more sensitive to green light, and less to blue.
+    vec grey = dot(color, vec3(0.3, 0.59, 0.11));
+
+    return lerp(grey, color, saturation);
+}
+
+void main()
+{
+	// Look up the bloom and original base image colors.
+	vec4 bloom = gl_Color * texture2D(BloomSampler, gl_TexCoord[0].xy);
+	vec4 base = gl_Color * texture2D(BaseSampler, gl_TexCoord[0].xy);
+	
+	// Adjust color saturation and intensity.
+	bloom = AdjustSaturation(bloom, BloomSaturation) * BloomIntensity;
+    base = AdjustSaturation(base, BaseSaturation) * BaseIntensity;
+    
+    // Darken down the base image in areas where there is a lot of bloom,
+    // to prevent things looking excessively burned-out.
+    base *= (1 - clamp(bloom,0.0,1.0));
+	
+    gl_FragColor = base + bloom;
+}

StarterKits/MacOS/VectorRumble/Content/Effects/BloomCombine.fx

@@ -23,7 +23,7 @@ float4 AdjustSaturation(float4 color, float saturation)
 }
 
 
-float4 PixelShader(float2 texCoord : TEXCOORD0) : COLOR0
+float4 PixelShaderFunction(float2 texCoord : TEXCOORD0) : COLOR0
 {
     // Look up the bloom and original base image colors.
     float4 bloom = tex2D(BloomSampler, texCoord);
@@ -46,6 +46,6 @@ technique BloomCombine
 {
     pass Pass1
     {
-        PixelShader = compile ps_2_0 PixelShader();
+        PixelShader = compile ps_2_0 PixelShaderFunction();
     }
 }

StarterKits/MacOS/VectorRumble/Content/Effects/BloomExtract.fsh

@@ -1,32 +1,15 @@
-uniform sampler2D bgl_RenderedTexture;
+uniform sampler2D TextureSampler;
+
+uniform vec2 BloomThreshold;
 
 void main()
 {
-   vec4 sum = vec4(0);
-   vec2 texcoord = vec2(gl_TexCoord[0]);
-   int j;
-   int i;
-
-   for( i= -4 ;i < 4; i++)
-   {
-        for (j = -3; j < 3; j++)
-        {
-            sum += texture2D(bgl_RenderedTexture, texcoord + vec2(j, i)*0.004) * 0.25;
-        }
-   }
-       if (texture2D(bgl_RenderedTexture, texcoord).r < 0.3)
-    {
-       gl_FragColor = sum*sum*0.012 + texture2D(bgl_RenderedTexture, texcoord);
-    }
-    else
-    {
-        if (texture2D(bgl_RenderedTexture, texcoord).r < 0.5)
-        {
-            gl_FragColor = sum*sum*0.009 + texture2D(bgl_RenderedTexture, texcoord);
-        }
-        else
-        {
-            gl_FragColor = sum*sum*0.0075 + texture2D(bgl_RenderedTexture, texcoord);
-        }
-    }
+	// Look up the original image color.
+	vec4 tex = gl_Color * texture2D(TextureSampler, gl_TexCoord[0].xy);
+	
+	// Adjust it to keep only values brighter than the specified threshold.
+	vec4 color = tex;
+	color *= clamp((tex.a - BloomThreshold) / (1 - BloomThreshold),0.0,1.0);
+	
+    gl_FragColor = color;
 }

StarterKits/MacOS/VectorRumble/Content/Effects/BloomExtract.fx

@@ -6,7 +6,7 @@ sampler TextureSampler : register(s0);
 float BloomThreshold;
 
 
-float4 PixelShader(float2 texCoord : TEXCOORD0) : COLOR0
+float4 PixelShaderFunction(float2 texCoord : TEXCOORD0) : COLOR0
 {
     // Look up the original image color.
     float4 c = tex2D(TextureSampler, texCoord);
@@ -20,6 +20,6 @@ technique BloomExtract
 {
     pass Pass1
     {
-        PixelShader = compile ps_2_0 PixelShader();
+        PixelShader = compile ps_2_0 PixelShaderFunction();
     }
 }

StarterKits/MacOS/VectorRumble/Content/Effects/GaussianBlur.fsh

@@ -1 +1,21 @@
+uniform sampler2D TextureSampler;
 
+#define SAMPLE_COUNT 15
+
+vec2 SampleOffsets[SAMPLE_COUNT];
+vec SampleWeights[SAMPLE_COUNT];
+
+void main()
+{
+	// Look up the original image color.
+	vec4 color = vec4(0);
+   	vec2 texcoord = vec2(gl_TexCoord[0]);
+	
+	// Combine a number of weighted image filter taps.
+    for (int i = 0; i < SAMPLE_COUNT; i++)
+    {
+        color += gl_Color * (texture2D(TextureSampler, texcoord + SampleOffsets[i]) * SampleWeights[i]);
+    }
+	
+    gl_FragColor = color;
+}

StarterKits/MacOS/VectorRumble/Content/Effects/GaussianBlur.fx

@@ -10,7 +10,7 @@ float2 SampleOffsets[SAMPLE_COUNT];
 float SampleWeights[SAMPLE_COUNT];
 
 
-float4 PixelShader(float2 texCoord : TEXCOORD0) : COLOR0
+float4 PixelShaderFunction(float2 texCoord : TEXCOORD0) : COLOR0
 {
     float4 c = 0;
     
@@ -28,6 +28,6 @@ technique GaussianBlur
 {
     pass Pass1
     {
-        PixelShader = compile ps_2_0 PixelShader();
+        PixelShader = compile ps_2_0 PixelShaderFunction();
     }
 }