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-rw-r--r--src/opengl/util/trap_exact_aa.glsl58
1 files changed, 0 insertions, 58 deletions
diff --git a/src/opengl/util/trap_exact_aa.glsl b/src/opengl/util/trap_exact_aa.glsl
deleted file mode 100644
index 1637f430b5..0000000000
--- a/src/opengl/util/trap_exact_aa.glsl
+++ /dev/null
@@ -1,58 +0,0 @@
-float quad_aa()
-{
- float top = min(gl_FragCoord.y + 0.5, gl_TexCoord[0].x);
- float bottom = max(gl_FragCoord.y - 0.5, gl_TexCoord[0].y);
-
- float area = top - bottom;
-
- float left = gl_FragCoord.x - 0.5;
- float right = gl_FragCoord.x + 0.5;
-
- // use line equations to compute intersections of left/right edges with top/bottom of truncated pixel
- vec4 vecX = gl_TexCoord[1].xxzz * vec2(top, bottom).xyxy + gl_TexCoord[1].yyww;
-
- vec2 invA = gl_TexCoord[0].zw;
-
- // transform right line to left to be able to use same calculations for both
- vecX.zw = 2.0 * gl_FragCoord.x - vecX.zw;
-
- vec2 topX = vec2(vecX.x, vecX.z);
- vec2 bottomX = vec2(vecX.y, vecX.w);
-
- // transform lines such that top intersection is to the right of bottom intersection
- vec2 topXTemp = max(topX, bottomX);
- vec2 bottomXTemp = min(topX, bottomX);
-
- // make sure line slope reflects mirrored lines
- invA = mix(invA, -invA, step(topX, bottomX));
-
- vec2 vecLeftRight = vec2(left, right);
-
- // compute the intersections of the lines with the left and right edges of the pixel
- vec4 intersectY = bottom + (vecLeftRight.xyxy - bottomXTemp.xxyy) * invA.xxyy;
-
- vec2 temp = mix(area - 0.5 * (right - bottomXTemp) * (intersectY.yw - bottom), // left < bottom < right < top
- (0.5 * (topXTemp + bottomXTemp) - left) * area, // left < bottom < top < right
- step(topXTemp, right.xx));
-
- vec2 excluded = 0.5 * (top - intersectY.xz) * (topXTemp - left); // bottom < left < top < right
-
- excluded = mix((top - 0.5 * (intersectY.yw + intersectY.xz)) * (right - left), // bottom < left < right < top
- excluded, step(topXTemp, right.xx));
-
- excluded = mix(temp, // left < bottom < right (see calculation of temp)
- excluded, step(bottomXTemp, left.xx));
-
- excluded = mix(vec2(area, area), // right < bottom < top
- excluded, step(bottomXTemp, right.xx));
-
- excluded *= step(left, topXTemp);
-
- return (area - excluded.x - excluded.y) * step(bottom, top);
-}
-
-void main()
-{
- gl_FragColor = quad_aa().xxxx;
-}
-