# Forest Radiance Field

**Repository Path**: sg-first/forest-radiance-field

## Basic Information

- **Project Name**: Forest Radiance Field
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2025-08-12
- **Last Updated**: 2025-08-12

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

RF Forest
============
实验了一下Radiance Field类方法。首先用视频生成了Luma Field和RF，使用Luma插件导入UE5

Luma Field
---------------
![RF](img/RF.png)

屏占比高的时候帧率急剧下降，5FPS左右（3060），搞的电脑都很卡

![RF](img/RF-sr.png)

GPU bound

![RF](img/RF-gpu.png)

估计是shader的问题，先看下插件源码：

``` cpp
void ALumaScene::RefreshNiagaraComponents()
{

	CreateBox(CropBox, "CropBox1_", {64, 64, 64});
	CreateBox(CullBox1, "CullBox1_", {1, 1, 1});	
	CreateBox(CullBox2, "CullBox2_", {1, 1, 1});	
	CreateBox(CullBox3, "CullBox3_", {1, 1, 1});	
	CreateBox(CullBox4, "CullBox4_", {1, 1, 1});	
	
	ApplyShaderParams();
	
#if WITH_EDITOR

	if(LumaNiagaraComponents.IsEmpty())
		return;
	
	for (int i = 0; i < LumaNiagaraComponents.Num(); i++)
	{
		if(LumaNiagaraComponents[i]->GetAsset() == nullptr)
			continue;
		
		LumaNiagaraComponents[i]->GetAsset()->EnsureFullyLoaded();
		LumaNiagaraComponents[i]->GetAsset()->InvalidateCachedData();
		LumaNiagaraComponents[i]->GetAsset()->RequestCompile(false);
	}
#endif
}

void ALumaField::ApplyShaderParams() const
{
	if(!LumaMaterialInstance)
		return;
	
	LumaMaterialInstance->SetVectorParameterValue(LumaConstants::CropMin, CropMin);
	LumaMaterialInstance->SetVectorParameterValue(LumaConstants::CropMax, CropMax);
	LumaMaterialInstance->SetVectorParameterValue(LumaConstants::CropCenter, CropCenter);
	LumaMaterialInstance->SetVectorParameterValue(LumaConstants::CropRotation, CropRotation.Euler());	
	LumaMaterialInstance->SetVectorParameterValue(LumaConstants::Exposure, Exposure);
	LumaMaterialInstance->SetScalarParameterValue(LumaConstants::QualityMode, static_cast<float>(QualityMode));	
}
```

看对应材质实现

![RF](img/RF-shader2.png)

![RF](img/RF-shader.png)

场景里用的这个材质PS指令数2193，可能是这里比较重。但材质函数梳理逻辑比较困难（很多节点+一些内嵌HLSL代码），不太好优化


3DGS
------------
体感上类似于把field里的信息在3D空间静态化了（基于Niagara渲染，而Luma Field是GPU driven的static mesh），不用一转视角就得重新跑shader里的raymarch，所以帧数有很大提升，平均帧率接近60，与示例空场景相差不大了，视觉效果整体也比Luma Field好一些（Luma Field比较糊，而且有距离近时物体会融化的问题。RF的import速度也比Luma Field快很多）

![RF](img/3DGS.png)

![RF](img/3DGS-sr.png)

![RF](img/3DGS-GPU.png)

各项stat数据也与空场景区别不大了