revert r28750 and r28588 to keep compatibility with opengl versions lower than 3.0

git-svn-id: https://xbmc.svn.sourceforge.net/svnroot/xbmc/trunk@28753 568bbfeb-2a22-0410-94d2-cc84cf5bfa90

2 files changed, 68 insertions, 49 deletions

diff --git a/system/shaders/convolution-4x4.glsl b/system/shaders/convolution-4x4.glsl
index 70813f45cb..fa3f8c11ec 100644
--- a/system/shaders/convolution-4x4.glsl
+++ b/system/shaders/convolution-4x4.glsl
@@ -1,22 +1,25 @@
-#version 130
-
 uniform sampler2D img;
 uniform sampler1D kernelTex;
 uniform vec2      stepxy;
 uniform float     m_stretch;
-out     vec4      gl_FragColor;
-in      vec4      gl_TexCoord[];
-in      vec4      gl_Color;
+
+//nvidia's half is a 16 bit float and can bring some speed improvements
+//without affecting quality
+#ifndef __GLSL_CG_DATA_TYPES
+  #define half float
+  #define half3 vec3
+  #define half4 vec4
+#endif
 
 #if (HAS_FLOAT_TEXTURE)
-vec4 weight(float pos)
+half4 weight(float pos)
 {
-  return texture(kernelTex, pos);
+  return texture1D(kernelTex, pos);
 }
 #else
-vec4 weight(float pos)
+half4 weight(float pos)
 {
-  return texture(kernelTex, pos) * 2.0 - 1.0;
+  return texture1D(kernelTex, pos) * 2.0 - 1.0;
 }
 #endif
 
@@ -33,13 +36,18 @@ vec2 stretch(vec2 pos)
 #endif
 }
 
-vec3 line (vec2 pos, const int yoffset, vec4 linetaps)
+half3 pixel(float xpos, float ypos)
+{
+  return texture2D(img, vec2(xpos, ypos)).rgb;
+}
+
+half3 line (float ypos, vec4 xpos, half4 linetaps)
 {
   return
-    textureOffset(img, pos, ivec2(-1, yoffset)).rgb * linetaps.r +
-    textureOffset(img, pos, ivec2( 0, yoffset)).rgb * linetaps.g +
-    textureOffset(img, pos, ivec2( 1, yoffset)).rgb * linetaps.b +
-    textureOffset(img, pos, ivec2( 2, yoffset)).rgb * linetaps.a;
+    pixel(xpos.r, ypos) * linetaps.r +
+    pixel(xpos.g, ypos) * linetaps.g +
+    pixel(xpos.b, ypos) * linetaps.b +
+    pixel(xpos.a, ypos) * linetaps.a;
 }
 
 void main()
@@ -47,20 +55,21 @@ void main()
   vec2 pos = stretch(gl_TexCoord[0].xy);
   vec2 f = fract(pos / stepxy);
 
-  vec4 linetaps   = weight(1.0 - f.x);
-  vec4 columntaps = weight(1.0 - f.y);
+  half4 linetaps   = weight(1.0 - f.x);
+  half4 columntaps = weight(1.0 - f.y);
 
   //make sure all taps added together is exactly 1.0, otherwise some (very small) distortion can occur
   linetaps /= linetaps.r + linetaps.g + linetaps.b + linetaps.a;
   columntaps /= columntaps.r + columntaps.g + columntaps.b + columntaps.a;
 
-  vec2 xystart = (0.5 - f) * stepxy + pos;
+  vec2 xystart = (-0.5 - f) * stepxy + pos;
+  vec4 xpos = vec4(xystart.x, xystart.x + stepxy.x, xystart.x + stepxy.x * 2.0, xystart.x + stepxy.x * 3.0);
 
   gl_FragColor.rgb =
-    line(xystart, -1, linetaps) * columntaps.r +
-    line(xystart,  0, linetaps) * columntaps.g +
-    line(xystart,  1, linetaps) * columntaps.b +
-    line(xystart,  2, linetaps) * columntaps.a;
+    line(xystart.y                 , xpos, linetaps) * columntaps.r +
+    line(xystart.y + stepxy.y      , xpos, linetaps) * columntaps.g +
+    line(xystart.y + stepxy.y * 2.0, xpos, linetaps) * columntaps.b +
+    line(xystart.y + stepxy.y * 3.0, xpos, linetaps) * columntaps.a;
 
   gl_FragColor.a = gl_Color.a;
 }
diff --git a/system/shaders/convolution-6x6.glsl b/system/shaders/convolution-6x6.glsl
index 7741a8c57f..f37dd6105a 100644
--- a/system/shaders/convolution-6x6.glsl
+++ b/system/shaders/convolution-6x6.glsl
@@ -1,22 +1,25 @@
-#version 130
-
 uniform sampler2D img;
 uniform sampler1D kernelTex;
 uniform vec2      stepxy;
 uniform float     m_stretch;
-out     vec4      gl_FragColor;
-in      vec4      gl_TexCoord[];
-in      vec4      gl_Color;
+
+//nvidia's half is a 16 bit float and can bring some speed improvements
+//without affecting quality
+#ifndef __GLSL_CG_DATA_TYPES
+  #define half float
+  #define half3 vec3
+  #define half4 vec4
+#endif
 
 #if (HAS_FLOAT_TEXTURE)
-vec3 weight(float pos)
+half3 weight(float pos)
 {
-  return texture(kernelTex, pos).rgb;
+  return texture1D(kernelTex, pos).rgb;
 }
 #else
-vec3 weight(float pos)
+half3 weight(float pos)
 {
-  return texture(kernelTex, pos).rgb * 2.0 - 1.0;
+  return texture1D(kernelTex, pos).rgb * 2.0 - 1.0;
 }
 #endif
 
@@ -33,15 +36,20 @@ vec2 stretch(vec2 pos)
 #endif
 }
 
-vec3 line (vec2 pos, const int yoffset, vec3 linetaps1, vec3 linetaps2)
+half3 pixel(float xpos, float ypos)
+{
+  return texture2D(img, vec2(xpos, ypos)).rgb;
+}
+
+half3 line (float ypos, vec3 xpos1, vec3 xpos2, half3 linetaps1, half3 linetaps2)
 {
   return
-    textureOffset(img, pos, ivec2(-2, yoffset)).rgb * linetaps1.r +
-    textureOffset(img, pos, ivec2(-1, yoffset)).rgb * linetaps2.r +
-    textureOffset(img, pos, ivec2( 0, yoffset)).rgb * linetaps1.g +
-    textureOffset(img, pos, ivec2( 1, yoffset)).rgb * linetaps2.g +
-    textureOffset(img, pos, ivec2( 2, yoffset)).rgb * linetaps1.b +
-    textureOffset(img, pos, ivec2( 3, yoffset)).rgb * linetaps2.b;
+    pixel(xpos1.r, ypos) * linetaps1.r +
+    pixel(xpos1.g, ypos) * linetaps2.r +
+    pixel(xpos1.b, ypos) * linetaps1.g +
+    pixel(xpos2.r, ypos) * linetaps2.g +
+    pixel(xpos2.g, ypos) * linetaps1.b +
+    pixel(xpos2.b, ypos) * linetaps2.b; 
 }
 
 void main()
@@ -49,28 +57,30 @@ void main()
   vec2 pos = stretch(gl_TexCoord[0].xy);
   vec2 f = fract(pos / stepxy);
 
-  vec3 linetaps1   = weight((1.0 - f.x) / 2.0);
-  vec3 linetaps2   = weight((1.0 - f.x) / 2.0 + 0.5);
-  vec3 columntaps1 = weight((1.0 - f.y) / 2.0);
-  vec3 columntaps2 = weight((1.0 - f.y) / 2.0 + 0.5);
+  half3 linetaps1   = weight((1.0 - f.x) / 2.0);
+  half3 linetaps2   = weight((1.0 - f.x) / 2.0 + 0.5);
+  half3 columntaps1 = weight((1.0 - f.y) / 2.0);
+  half3 columntaps2 = weight((1.0 - f.y) / 2.0 + 0.5);
 
   //make sure all taps added together is exactly 1.0, otherwise some (very small) distortion can occur
-  float sum = linetaps1.r + linetaps1.g + linetaps1.b + linetaps2.r + linetaps2.g + linetaps2.b;
+  half sum = linetaps1.r + linetaps1.g + linetaps1.b + linetaps2.r + linetaps2.g + linetaps2.b;
   linetaps1 /= sum;
   linetaps2 /= sum;
   sum = columntaps1.r + columntaps1.g + columntaps1.b + columntaps2.r + columntaps2.g + columntaps2.b;
   columntaps1 /= sum;
   columntaps2 /= sum;
 
-  vec2 xystart = (0.5 - f) * stepxy + pos;
+  vec2 xystart = (-1.5 - f) * stepxy + pos;
+  vec3 xpos1 = vec3(xystart.x, xystart.x + stepxy.x, xystart.x + stepxy.x * 2.0);
+  vec3 xpos2 = vec3(xystart.x + stepxy.x * 3.0, xystart.x + stepxy.x * 4.0, xystart.x + stepxy.x * 5.0);
 
   gl_FragColor.rgb =
-   line(xystart, -2, linetaps1, linetaps2) * columntaps1.r +
-   line(xystart, -1, linetaps1, linetaps2) * columntaps2.r +
-   line(xystart,  0, linetaps1, linetaps2) * columntaps1.g +
-   line(xystart,  1, linetaps1, linetaps2) * columntaps2.g +
-   line(xystart,  2, linetaps1, linetaps2) * columntaps1.b +
-   line(xystart,  3, linetaps1, linetaps2) * columntaps2.b;
+   line(xystart.y                 , xpos1, xpos2, linetaps1, linetaps2) * columntaps1.r +
+   line(xystart.y + stepxy.y      , xpos1, xpos2, linetaps1, linetaps2) * columntaps2.r +
+   line(xystart.y + stepxy.y * 2.0, xpos1, xpos2, linetaps1, linetaps2) * columntaps1.g +
+   line(xystart.y + stepxy.y * 3.0, xpos1, xpos2, linetaps1, linetaps2) * columntaps2.g +
+   line(xystart.y + stepxy.y * 4.0, xpos1, xpos2, linetaps1, linetaps2) * columntaps1.b +
+   line(xystart.y + stepxy.y * 5.0, xpos1, xpos2, linetaps1, linetaps2) * columntaps2.b;
 
   gl_FragColor.a = gl_Color.a;
 }