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HSLBlend images alpha fix

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This commit is contained in:
justburner 2023-01-22 03:24:18 +00:00 committed by manongjohn
parent 7b474d9950
commit b33713d62d
1 changed files with 6 additions and 14 deletions
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20
stuff/library/shaders/programs/HSLBlendGPU.frag
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@ -95,7 +95,7 @@ void main( void )
vec4 fg_frag = texture2D(inputImage[0], fg_texPos);
vec4 bg_frag = texture2D(inputImage[1], bg_texPos);
// De-premultiplication
// De-premultiplication of textures
vec3 fg_pix = vec3(0.0);
if (fg_frag.a > 0.0) fg_pix = fg_frag.rgb / fg_frag.a;
vec3 bg_pix = vec3(0.0);
@ -107,20 +107,12 @@ void main( void )
if (bmask) {
gl_FragColor.a = bg_alpha;
} else {
gl_FragColor.a = fg_alpha + bg_alpha * (1.0 - fg_alpha);
gl_FragColor.a = bg_alpha + fg_alpha * (1.0 - bg_alpha);
}
if (gl_FragColor.a <= 0.0) discard;
// Perform blending
if (fg_alpha > 0.0 && bg_alpha > 0.0) {
vec3 o_pix = SetLumSat(bhue ? fg_pix : bg_pix, bsat ? fg_pix : bg_pix, blum ? fg_pix : bg_pix);
gl_FragColor.rgb = mix(bg_pix, o_pix, balpha);
} else if (fg_alpha > 0.0) {
gl_FragColor.rgb = fg_pix;
} else {
gl_FragColor.rgb = bg_pix;
}
// Premultiplication
gl_FragColor.rgb *= gl_FragColor.a;
// Perform blending
vec3 o_pix = SetLumSat(bhue ? fg_pix : bg_pix, bsat ? fg_pix : bg_pix, blum ? fg_pix : bg_pix);
vec3 b_pix = bmask ? vec3(0.0) : fg_pix;
gl_FragColor.rgb = bg_pix * bg_alpha * (1.0 - fg_alpha) + mix(b_pix, o_pix, bg_alpha) * fg_alpha;
}