uniform vec2 texelSize;

out vec2 vCenterUv1;
out vec2 vCenterUv2;
out vec2 vCenterUv3;
out vec2 vCenterUv4;
out vec2 vRowUv1;
out vec2 vRowUv2;
out vec2 vRowUv3;
out vec2 vRowUv4;
out vec2 vRowUv5;
out vec2 vRowUv6;
out vec2 vRowUv7;
out vec2 vRowUv8;
out vec2 vRowUv9;

void main() {
  vec2 uv = position.xy * 0.5 + 0.5;
  vCenterUv1 = uv + texelSize * vec2(-1.0, 1.0);
  vCenterUv2 = uv + texelSize * vec2(1.0, 1.0);
  vCenterUv3 = uv + texelSize * vec2(-1.0, -1.0);
  vCenterUv4 = uv + texelSize * vec2(1.0, -1.0);
  vRowUv1 = uv + texelSize * vec2(-2.0, 2.0);
  vRowUv2 = uv + texelSize * vec2(0.0, 2.0);
  vRowUv3 = uv + texelSize * vec2(2.0, 2.0);
  vRowUv4 = uv + texelSize * vec2(-2.0, 0.0);
  vRowUv5 = uv + texelSize;
  vRowUv6 = uv + texelSize * vec2(2.0, 0.0);
  vRowUv7 = uv + texelSize * vec2(-2.0, -2.0);
  vRowUv8 = uv + texelSize * vec2(0.0, -2.0);
  vRowUv9 = uv + texelSize * vec2(2.0, -2.0);

  gl_Position = vec4(position.xy, 1.0, 1.0);
}