axmol/tests/cpp-tests/Resources/Shaders/example_Blur.fsh

49 lines
1.0 KiB
GLSL

#ifdef GL_ES
precision mediump float;
#endif
varying vec4 v_fragmentColor;
varying vec2 v_texCoord;
uniform vec2 resolution;
uniform float blurRadius;
uniform float sampleNum;
uniform sampler2D u_texture;
vec4 blur(vec2);
void main(void)
{
vec4 col = blur(v_texCoord); //* v_fragmentColor.rgb;
gl_FragColor = vec4(col) * v_fragmentColor;
}
vec4 blur(vec2 p)
{
if (blurRadius > 0.0 && sampleNum > 1.0)
{
vec4 col = vec4(0);
vec2 unit = 1.0 / resolution.xy;
float r = blurRadius;
float sampleStep = r / sampleNum;
float count = 0.0;
for(float x = -r; x < r; x += sampleStep)
{
for(float y = -r; y < r; y += sampleStep)
{
float weight = (r - abs(x)) * (r - abs(y));
col += texture2D(u_texture, p + vec2(x * unit.x, y * unit.y)) * weight;
count += weight;
}
}
return col / count;
}
return texture2D(u_texture, p);
}