24 lines
519 B
GLSL
24 lines
519 B
GLSL
/* Viewport width and height */
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uniform ivec2 viewport_size;
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/* Position of lower left corner of rectangle */
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uniform ivec2 position;
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/* Size of the rectangle */
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uniform ivec2 size;
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/* Vertex coordinates: x, y (0 or 1) */
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attribute ivec2 coords;
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/**
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* Map coordinates such that:
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* (0 .. viewport_size.[xy]) => (-1.0 .. 1.0)
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*/
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vec2 map_to_screen(vec2 position)
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{
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return 2.0 * position / viewport_size - 1.0;
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}
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void main(void)
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{
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gl_Position = vec4(map_to_screen((vec2)(position + coords * size)), 0, 1);
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}
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