attribute vec4 a_position;
attribute vec2 a_texCoord;
uniform vec2 u_diffUVSize;

uniform vec2 u_uvSize;
varying vec2 v_texCoord;
varying vec2 v_diffTexCoord;

void main()
{
    gl_Position = a_position;
    v_texCoord = a_texCoord;
    v_diffTexCoord = a_texCoord * u_diffUVSize;
}
