diff options
Diffstat (limited to 'src/effects/shaders_ng/displace.frag')
-rw-r--r-- | src/effects/shaders_ng/displace.frag | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/src/effects/shaders_ng/displace.frag b/src/effects/shaders_ng/displace.frag new file mode 100644 index 0000000..df6bc78 --- /dev/null +++ b/src/effects/shaders_ng/displace.frag @@ -0,0 +1,39 @@ +#version 440 + +layout(location = 0) in vec2 qt_TexCoord0; +layout(location = 0) out vec4 fragColor; + +layout(std140, binding = 0) uniform buf { + // qt_Matrix and qt_Opacity must always be both present + // if the built-in vertex shader is used. + mat4 qt_Matrix; + float qt_Opacity; + float displacement; + float xPixel; + float yPixel; +}; + +layout(binding = 1) uniform sampler2D source; +layout(binding = 2) uniform sampler2D displacementSource; + +float linearstep(float e0, float e1, float x) +{ + return clamp((x - e0) / (e1 - e0), 0.0, 1.0); +} + +void main() +{ + vec4 offset = texture(displacementSource, qt_TexCoord0); + offset.xy -= vec2(0.5, 0.5); + offset.xy = offset.xy * step(vec2(1.0/256.0), abs(offset.xy)); + vec2 tx = qt_TexCoord0 + (vec2(-offset.x, offset.y) * displacement); + + float e1 = linearstep(0.0, xPixel, tx.x); + float e2 = linearstep(0.0, yPixel, tx.y); + float e3 = 1.0 - linearstep(1.0, 1.0 + xPixel, tx.x); + float e4 = 1.0 - linearstep(1.0, 1.0 + yPixel, tx.y); + + vec4 samp = texture(source, tx); + samp.rgb *= e1 * e2 * e3 * e4; + fragColor = samp * qt_Opacity * offset.a; +} |