attribute vec2 a_position;
attribute vec2 a_texCoord;
varying vec2 v_texCoord;
varying vec2 v_pixNo;
uniform vec2 u_outputSize;

void main() {
    gl_Position = vec4(a_position, 0.0, 1.0);
    v_texCoord = a_texCoord;
    v_pixNo = a_texCoord * u_outputSize;
}
