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

22 lines
448 B
GLSL

/* Viewport width and height */
uniform ivec2 viewport_size;
/* Position of lower left corner of glyph */
uniform ivec2 position;
/* Vertex coordinates: x, y */
attribute vec2 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), 0, 1);
}