Unity Shader 获取屏幕坐标检测测试

v2f vert(appdata_t v)
{
    
    
    v2f OUT;

    OUT.vertex = vPosition;
    OUT.screenPos = ComputeScreenPos(OUT.vertex);
    return OUT;
}

fixed4 frag(v2f IN) : SV_Target
{
    
    
    half4 color = IN.color * (tex2D(_MainTex, IN.texcoord) + _TextureSampleAdd);

    float2 screenPos = IN.screenPos;
    screenPos.xy *= _ScreenParams.xy;
    screenPos.xy = floor(screenPos.xy * 0.1) * 0.5;
    float checker = -frac(screenPos.r + screenPos.g);
    clip(checker);

    return color;
}