42 lines
1.2 KiB
GLSL
42 lines
1.2 KiB
GLSL
//-----------------------------------------------------------------------------
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// SolveSpace Edge rendering shader
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//
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// Copyright 2016 Aleksey Egorov
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//-----------------------------------------------------------------------------
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const float feather = 0.5;
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attribute vec3 pos;
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attribute vec3 loc;
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attribute vec3 tan;
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uniform mat4 modelview;
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uniform mat4 projection;
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uniform float width;
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uniform float pixel;
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varying vec3 fragLoc;
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void main() {
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// get camera direction from modelview matrix
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vec3 dir = vec3(modelview[0].z, modelview[1].z, modelview[2].z);
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// calculate line contour extension basis for constant width and caps
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vec3 norm = normalize(cross(tan, dir));
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norm = normalize(norm - dir * dot(dir, norm));
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vec3 perp = normalize(cross(dir, norm));
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// calculate line extension width considering antialiasing
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float ext = width + feather * pixel;
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// extend line contour
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vec3 vertex = pos;
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vertex += ext * loc.x * normalize(perp);
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vertex += ext * loc.y * normalize(norm);
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// write fragment location for calculating caps and antialiasing
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fragLoc = loc;
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// transform resulting vertex with modelview and projection matrices
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gl_Position = projection * modelview * vec4(vertex, 1.0);
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}
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