IN(0) vec2 in_position;
IN(1) vec2 in_tex_coord_0;

UNIFORM_BEGIN
  UNIFORM_V(vec2 scale)
  UNIFORM_V(mat4 projection)
  UNIFORM_F(vec2 sky_offset)
UNIFORM_END

OUT(0) vec2 tex_coord_0;

void main() {
  // Simple 2d transform.
  vec2 position = in_position;
  position *= PARAM(scale);

  tex_coord_0 = in_tex_coord_0;

  gl_Position = PARAM(projection) * vec4(position, 0.0, 1.0);
}