struct VS_Output
{  
    float4 Pos : SV_POSITION;              
    float2 Tex : TEXCOORD0;
};
 
VS_Output Video_VS(uint id : SV_VertexID)
{
    VS_Output Output;
    Output.Tex = float2((id << 1) & 2, id & 2);
    Output.Pos = float4(Output.Tex * float2(2,-2) + float2(-1,1), 0, 1);
    return Output;
}
