planet-wars/frontend/www/static/shaders/vert/vor.glsl
2019-09-24 14:29:13 +02:00

26 lines
519 B
GLSL

#ifdef GL_ES
precision mediump float;
#endif
attribute vec2 a_pos;
uniform vec4 u_viewbox; // [x, y, width, height]
uniform vec2 u_resolution;
varying vec2 v_pos;
void main() {
vec2 uv = (a_pos.xy + 1.0) * 0.5;
uv = 1.0 - uv;
// uv *= -1.0;
// Viewbox's center is top left, a_position's is in the center to the screen
// So translate and scale the viewbox**
uv *= u_viewbox.zw;
uv -= u_viewbox.xy + u_viewbox.zw;
v_pos = uv.xy;
gl_Position = vec4(a_pos, 0.0, 1.0);
}