tab.vert

 1attribute highp vec2 pos;
 2
 3uniform mat3 proj;
 4uniform highp vec2 pixelOffset;
 5uniform highp vec2 pixelSize;
 6uniform highp vec2 monitorSize;
 7
 8varying highp vec2 pixCoord;
 9varying highp vec2 monitorTexCoord;
10
11void main() {
12	pixCoord = pos * pixelSize;
13	monitorTexCoord = (pixelOffset + pixCoord) / monitorSize;
14	gl_Position = vec4(proj * vec3(monitorTexCoord, 1.0), 1.0);
15}