jes-ruby/runtime/shaders/rect.v.glsl

26 lines
545 B
GLSL

#version 410
/* Viewport width and height */
uniform ivec2 viewport_size;
/* Position of lower left corner of rectangle */
uniform ivec2 position;
/* Size of the rectangle */
uniform ivec2 size;
/* Vertex coordinates: x, y (0 or 1) */
layout(location = 0) in ivec2 coords;
/**
* Map coordinates such that:
* (0 .. viewport_size.[xy]) => (-1.0 .. 1.0)
*/
vec2 map_to_screen(vec2 position)
{
return 2.0 * position / viewport_size - 1.0;
}
void main(void)
{
gl_Position = vec4(map_to_screen(vec2(position + coords * size)), 0, 1);
}