2023.06.04

• DLSS, FSR, TSR
• output quantization error

DLSS, FSR, TSR

https://zhuanlan.zhihu.com/p/598916763
https://github.com/GPUOpen-Effects/FidelityFX-FSR2

output quantization error

UE TAA output 最后加了一个很小的noise
Stocastically round up or down using the hardware RWTexture2D truncation unit to take into precision loss due to pixel format encoding.

taa_half3 QuantizeForFloatRenderTarget(taa_half3 Color, taa_half E, float3 QuantizationError)
{
	taa_half3 Error = Color * taa_half3(QuantizationError);

	#if 0
		// NOP
	#elif CONFIG_COMPILE_FP16
	{
		uint16_t3 UError = asint16(Error);

		Error = asfloat16(UError & uint16_t(~0x03FF));
	}
	#else
	{
		Error.x = asfloat(asuint(Error.x) & ~0x007FFFFF);
		Error.y = asfloat(asuint(Error.y) & ~0x007FFFFF);
		Error.z = asfloat(asuint(Error.z) & ~0x007FFFFF);
	}
	#endif
	
	return Color + Error * E;
}