planetwars.dev/web/pw-visualizer/assets/shaders/vert/image.glsl
2021-12-29 22:54:30 +01:00

33 lines
688 B
GLSL

#ifdef GL_ES
precision mediump float;
#endif
attribute vec2 a_position;
attribute vec2 a_texCoord;
uniform float u_time;
uniform vec4 u_viewbox; // [x, y, width, height]
uniform vec2 u_resolution;
uniform mat3 u_trans;
varying vec2 v_pos;
varying vec2 v_texCoord;
void main() {
vec3 pos = vec3(a_position, 1.0);
pos = u_trans * pos;
vec2 uv = pos.xy;
// 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.xy + (u_viewbox.zw * 0.5);
uv /= u_viewbox.zw * 0.5;
v_pos = (uv.xy + 1.0) * 0.5;
gl_Position = vec4(uv.xy, 0.0, 1.0);
v_texCoord = a_texCoord;
}