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

client/renderers/EGL/shader/ffx_fsr1_rcas.frag

@@ -0,0 +1,36 @@
+#version 300 es
+precision mediump float;
+
+#include "compat.h"
+
+in  vec2  iFragCoord;
+out vec4  fragColor;
+
+uniform sampler2D iChannel0;
+uniform uvec2     uInRes[8];
+uniform float     uSharpness;
+
+#define A_GPU  1
+#define A_GLSL 1
+#define A_FULL 1
+
+#include "ffx_a.h"
+
+AF4 FsrRcasLoadF(ASU2 p) { return texelFetch(iChannel0, ASU2(p), 0); }
+void FsrRcasInputF(inout AF1 r, inout AF1 g, inout AF1 b) {}
+
+#define FSR_RCAS_F       1
+#define FSR_RCAS_DENOISE 1
+#include "ffx_fsr1.h"
+
+void main()
+{
+  vec2 inRes  = vec2(uInRes[0]);
+  uvec2 point = uvec2(iFragCoord * inRes);
+
+  uvec4 const0;
+  FsrRcasCon(const0, 1.0f - uSharpness);
+
+  FsrRcasF(fragColor.r, fragColor.g, fragColor.b, point, const0);
+  fragColor.a = 1.0f;
+}