struct Output {
  float4 position : POSITION;
  float3 color    : COLOR;
};

Output vert_shader(float4 position : POSITION,
				   float4 color    : COLOR,
				   uniform float twisting,
				   uniform float4x4 MVP : state.matrix.mvp)
{	
  Output OUT;

  OUT.position[0] = position[0];
  OUT.position[1] = position[1];
  OUT.position[2] = 0;
  OUT.position[3] = 1;

  OUT.position = mul(MVP, OUT.position);

  OUT.color = color;
  return OUT;	
}