https://github.com/finger563/unreal-pgm

Projective Grid Mapping for Planetary Terrain Implementation for Unreal Engine 4 / 5
https://github.com/finger563/unreal-pgm

Last synced: 13 days ago
JSON representation

Projective Grid Mapping for Planetary Terrain Implementation for Unreal Engine 4 / 5

• Host: GitHub
• URL: https://github.com/finger563/unreal-pgm
• Owner: finger563
• License: mit
• Created: 2021-12-19T20:15:41.000Z (about 3 years ago)
• Default Branch: main
• Last Pushed: 2021-12-29T22:35:00.000Z (almost 3 years ago)
• Last Synced: 2024-10-26T03:51:38.310Z (about 2 months ago)
• Size: 49.8 MB
• Stars: 0
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

        
# unreal-pgm

Projective Grid Mapping for Planetary Terrain Implementation for Unreal Engine 4 / 5

## References

* [Projective Grid Mapping for Planetary Terrain (Thesis)](https://www.cse.unr.edu/~fredh/papers/thesis/046-mahsman/thesis.pdf) (2010)

* [Projective Grid Mapping for Planetary Terrain Visualization (YouTube)](https://www.youtube.com/watch?v=xtFxDCJE-0Y) (2012)

* [Geometry Reinvented with Mesh Shading - NVIDIA SIGGRAPH 2019](https://www.youtube.com/watch?v=rLEbO0Vrzz4) (2019)

* [Planetary Rendering With Mesh Shaders](https://www.cg.tuwien.ac.at/research/publications/2020/rumpelnik_martin_2020_PRM/rumpelnik_martin_2020_PRM-Thesis.pdf) (2020)

## Progress

So far I've gotten a basic matirial which projects from absolute world position

onto a sphere with the given center and radius. This is applied to sprites of a

niagra emitter which spawns particles in a grid (statically) and those particles

/ that grid are placed very close in front of the camera, approximating the

screen-space grid from the PGM paper.

### Current Images

Textured (Earth) onto PGM sphere:

![Textured PGM](./images/textured_pgm.png)

Normal Vector visualized on PGM sphere

![Textured PGM](./images/normal_1_pgm.png)

### Older Images

Here is an example of the current (very beta) version of that system:

![Example PGM](./images/pgm_test.png)

Here is that same scene, but in wireframe mode:

![Wireframe PGM](./images/wireframe_pgm.png)

## TODO

- [ ] Better ray-sphere intersection calculation to move the vertices of near-misses onto the sphere for smoother sphere edge without needing to drastically increase the resolution of the particle grid

- [ ] Better management of particle spawning to remove motion blur and ensure that it updates frequently enough

- [x] Better calculation of normal / tangent vectors (since they seem to be .... not so great...)

- [ ] Update to affect lighting (since right now the particles (and thus the sphere) don't affect the lighting in the scene / don't cast shadows)

- [x] Texture mapping onto the sphere

- [ ] Height mapping / displacement onto the sphere (texture lookup)

- [ ] Conversion of height map into TSDF for use in ray-sphere ray-sdf intersection calculation

- [ ] Addition of atmosphere shader / integration with UE atmosphere system?

- [ ] Addition of water shader / integration with UE water system?

- [ ] Addition of clouds / integration with UE cloud system?