factor/extra/gpu/effects/blur/blur.factor

83 lines
3.3 KiB
Factor

! Copyright (C) 2010 Erik Charlebois.
! See http://factorcode.org/license.txt for BSD license.
USING: arrays destructors fry gpu.framebuffers gpu.render gpu.shaders
gpu.state gpu.textures gpu.util images kernel locals math
math.rectangles sequences ;
IN: gpu.effects.blur
GLSL-SHADER: blur-fragment-shader fragment-shader
uniform sampler2D texture;
uniform bool horizontal;
uniform float blurSize;
varying vec2 texcoord;
void main()
{
vec4 col = 0.16 * texture2D(texture, texcoord);
if (horizontal)
{
vec2 blurX1 = vec2(blurSize, 0.0);
vec2 blurX2 = vec2(blurSize * 2.0, 0.0);
vec2 blurX3 = vec2(blurSize * 3.0, 0.0);
vec2 blurX4 = vec2(blurSize * 4.0, 0.0);
col += 0.15 * ( texture2D(texture, texcoord - blurX1)
+ texture2D(texture, texcoord + blurX1));
col += 0.12 * ( texture2D(texture, texcoord - blurX2)
+ texture2D(texture, texcoord + blurX2));
col += 0.09 * ( texture2D(texture, texcoord - blurX3)
+ texture2D(texture, texcoord + blurX3));
col += 0.05 * ( texture2D(texture, texcoord - blurX4)
+ texture2D(texture, texcoord + blurX4));
}
else
{
vec2 blurY1 = vec2(0.0, blurSize);
vec2 blurY2 = vec2(0.0, blurSize * 2.0);
vec2 blurY3 = vec2(0.0, blurSize * 3.0);
vec2 blurY4 = vec2(0.0, blurSize * 4.0);
col += 0.15 * ( texture2D(texture, texcoord - blurY1)
+ texture2D(texture, texcoord + blurY1));
col += 0.12 * ( texture2D(texture, texcoord - blurY2)
+ texture2D(texture, texcoord + blurY2));
col += 0.09 * ( texture2D(texture, texcoord - blurY3)
+ texture2D(texture, texcoord + blurY3));
col += 0.05 * ( texture2D(texture, texcoord - blurY4)
+ texture2D(texture, texcoord + blurY4));
}
gl_FragColor = col;
}
;
UNIFORM-TUPLE: blur-uniforms
{ "texture" texture-uniform f }
{ "horizontal" bool-uniform f }
{ "blurSize" float-uniform f } ;
GLSL-PROGRAM: blur-program window-vertex-shader blur-fragment-shader window-vertex-format ;
:: (blur) ( texture horizontal? framebuffer dim -- )
{ 0 0 } dim <rect> <viewport-state> set-gpu-state
texture horizontal? 1.0 dim horizontal? [ first ] [ second ] if / blur-uniforms boa framebuffer {
{ "primitive-mode" [ 2drop triangle-strip-mode ] }
{ "uniforms" [ drop ] }
{ "vertex-array" [ 2drop blur-program <program-instance> <window-vertex-array> &dispose ] }
{ "indexes" [ 2drop T{ index-range f 0 4 } ] }
{ "framebuffer" [ nip ] }
} 2<render-set> render ;
:: blur ( texture horizontal? -- texture )
texture 0 texture-dim :> dim
dim RGB float-components <2d-render-texture> :> ( target-framebuffer target-texture )
texture horizontal? target-framebuffer dim (blur)
target-framebuffer dispose
target-texture ;
: horizontal-blur ( texture -- texture ) t blur ; inline
: vertical-blur ( texture -- texture ) f blur ; inline
: discompose ( quot1 quot2 -- compose )
'[ @ &dispose @ ] with-destructors ; inline
: gaussian-blur ( texture -- texture )
[ horizontal-blur ] [ vertical-blur ] discompose ;