hietwll / fumeng

Fumeng path tracing engine

Fumeng (浮梦)

Fumeng is a hobby project which implements a monte-carlo path tracer from scratch. Fumeng means illusory dream in English.

Features

Camera

• Pin-hole camera
• Thin-lens camera (with depth of field)

Shape

• Sphere
• Rectangle
• Triangle
• OBJ mesh

Material

• Lambert diffuse
• Specular reflection
• Specular transmission
• Disney BSDF
• Subsurface scatering
• Volumetric media

Light

• Directional light
• Area light
• Image-based light (HDR)

Accelerator

• Built-in BVH
• Embree BVH (opitional, but highly recommended)

Ray Tracer

• Basic monte-carlo path tracer
• Bidirectional path tracer

Sampling

• Multiple importance sampling

Denoise

• OIDN denoise (opitional, but highly recommended)

Post process

• Tonemapping

Texture

• Image texture
• Constant texture
• Checkerboard

Scene format

• Custom description using json

Build and Run

1. Download source code

git clone --recursive https://github.com/hietwll/Fumeng.git

2. Install third-party libraries

Both Embree and OIDN are optional for Fumeng, but it's strongly recommended to use them. You can just download the pre-built packages from their websites, and extract the packages.

Embree: windows and linux

OIDN: windows and linux

3. Config

cd /path/to/fumeng
cmake -B build -DCMAKE_BUILD_TYPE=Release -DUSE_FLOAT=TRUE -DUSE_EMBREE=TRUE -DUSE_OIDN=TRUE -Dembree_DIR=/path/to/embree/lib/cmake/embree-x.x.x -DOpenImageDenoise_DIR=/path/to/oidn/lib/cmake/OpenImageDenoise-x.x.x

• -DUSE_FLOAT: use single precision if TRUE, use double precision if FALSE
• -Dembree_DIR: directory of embree cmake config file
• -DOpenImageDenoise_DIR: directory of embree cmake config file

4. Build

cmake --build build --parallel 4 --target CMD_EXE

Supported complier:

• VS 2017/2019 for windows
• gcc and clang for linux

5. Run

cd /path/to/fumeng/scenes
../build/src/cmd/CMD_EXE DamagedHelmet/DamagedHelmet.json

result can be found in the same directory of the scene file.

Scenes

Damaged Helmet:

DoF Camera:

Substance Boy:

Hyperion:

Storm Trooper:

Dining Room:

Classroom: