added shader programs for variance shadow mapping with blur

src/fgt/decorate_shadow/shader/vsmb/blurVSM.frag

@@ -0,0 +1,17 @@
+uniform sampler2D scene;
+uniform vec2 scale;
+void main() {
+    vec4 color = vec4(vec3(0.0), 1.0);
+
+    color += texture2D( scene, gl_TexCoord[0].st + vec2( -3.0 * scale.x, -3.0 * scale.y ) ) * 0.015625;
+    color += texture2D( scene, gl_TexCoord[0].st + vec2( -2.0 * scale.x, -2.0 * scale.y ) )*0.09375;
+    color += texture2D( scene, gl_TexCoord[0].st + vec2( -1.0 * scale.x, -1.0 * scale.y) )*0.234375;
+    color += texture2D( scene, gl_TexCoord[0].st + vec2( 0.0 , 0.0) )*0.3125;
+    color += texture2D( scene, gl_TexCoord[0].st + vec2( 1.0 * scale.x,  1.0 * scale.y ) )*0.234375;
+    color += texture2D( scene, gl_TexCoord[0].st + vec2( 2.0 * scale.x,  2.0 * scale.y ) )*0.09375;
+    color += texture2D( scene, gl_TexCoord[0].st + vec2( 3.0 * scale.x, -3.0 * scale.y ) ) * 0.015625;
+    
+    if(color.x == 1.0 && color.y == 1.0 && color.z == 1.0)
+      discard;
+    gl_FragColor = color;
+}

src/fgt/decorate_shadow/shader/vsmb/blurVSM.vert

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+void main(){
+  gl_Position = ftransform();
+  gl_TexCoord[0] = gl_MultiTexCoord0;
+}

src/fgt/decorate_shadow/shader/vsmb/depthVSM.frag

@@ -0,0 +1,16 @@
+varying vec4 point;
+
+void main(void)
+{
+  float depth = point.z;// / point.w;
+  depth = depth * 0.5 + 0.5;
+  
+  float moment1 = depth;
+  float moment2 = depth * depth;
+
+  float dx = dFdx(depth);
+  float dy = dFdy(depth);
+  moment2 += 0.25 * (dx * dx + dy * dy);
+
+  gl_FragColor = vec4(moment1, moment2 , 0.0, 1.0);
+}

src/fgt/decorate_shadow/shader/vsmb/depthVSM.vert

@@ -0,0 +1,6 @@
+varying vec4 point;
+
+void main(){
+  gl_Position = ftransform();
+  point = gl_Position;
+}

src/fgt/decorate_shadow/shader/vsmb/objectVSM.frag

@@ -0,0 +1,40 @@
+uniform mat4 mvpl;
+uniform sampler2D shadowMap;
+uniform float texSize;
+varying vec4 shadowCoord; 
+
+
+vec4 shadowCoordPostW;
+float chebyshevUpperBound( float distance) {
+  // We retrive the two moments previously stored (depth and depth*depth) 
+  vec2 moments = texture2D(shadowMap,shadowCoordPostW.xy).rb; 
+  // Surface is fully lit. as the current fragment is before the light occluder 
+  if (distance <= moments.x) 
+    return 1.0 ; 
+
+  float variance = moments.y - (moments.x*moments.x); 
+  //variance = max(variance,0.00002);
+  variance = max(variance,0.000195);  
+  float d = distance - moments.x; 
+  float p_max = variance / (variance + d*d); 
+  return p_max;
+}
+
+void main() {
+  shadowCoordPostW = shadowCoord / shadowCoord.w;
+  shadowCoordPostW = shadowCoordPostW * 0.5 + 0.5;
+  float shadow = chebyshevUpperBound(shadowCoordPostW.z);
+
+  //vec4 ka = gl_LightSource[0].ambient;
+  vec4 kd = gl_LightSource[0].diffuse;
+  //vec4 ks = gl_LightSource[0].specular;
+  //vec4 color = ka + kd + ks;
+  //vec4 color = vec4(vec3(0.5), 1.0);
+  //gl_FragColor = vec4(shadow ) * color;
+  if (shadow > 0.4){
+    //discard;
+      gl_FragColor = vec4(vec3(kd), 0.0);
+  }
+    else
+      gl_FragColor = vec4(vec3(shadow), 1.0);
+} 

src/fgt/decorate_shadow/shader/vsmb/objectVSM.vert

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+uniform mat4 mvpl;
+varying vec4 shadowCoord; 
+void main() { 
+shadowCoord= mvpl * gl_Vertex;
+gl_Position = ftransform(); 
+}