[client] egl: rework post process filters and add AMD FXR

client/renderers/EGL/shader/compat.h

@@ -0,0 +1,32 @@
+#if __VERSION__ == 300
+  vec4 textureGather(sampler2D tex, vec2 uv, int comp)
+  {
+    vec4 c0 = textureOffset(tex, uv, ivec2(0,1));
+    vec4 c1 = textureOffset(tex, uv, ivec2(1,1));
+    vec4 c2 = textureOffset(tex, uv, ivec2(1,0));
+    vec4 c3 = textureOffset(tex, uv, ivec2(0,0));
+    return vec4(c0[comp], c1[comp], c2[comp],c3[comp]);
+  }
+#elif __VERSION__ < 300
+  vec4 textureGather(sampler2D tex, vec2 uv, int comp)
+  {
+    vec4 c3 = texture2D(tex, uv);
+    return vec4(c3[comp], c3[comp], c3[comp],c3[comp]);
+  }
+#endif
+
+#if __VERSION__ < 310
+  uint bitfieldExtract(uint val, int off, int size)
+  {
+    uint mask = uint((1 << size) - 1);
+    return uint(val >> off) & mask;
+  }
+
+  uint bitfieldInsert(uint a, uint b, int c, int d)
+  {
+    uint mask = ~(0xffffffffu << d) << c;
+    mask = ~mask;
+    a &= mask;
+    return a | (b << c);
+  }
+#endif