recp / gkern Goto Github PK

https://stackoverflow.com/questions/23280692/opengl-es2-alpha-test-problems/23283256#23283256

https://www.opengl.org/archives/resources/faq/technical/transparency.htm

Possible Techniques:

1. Alpha Testing
2. Sorting and Blending
3. Depth Peeling
4. Alpha to Coverage
5. Screen door transparency

Hello,

I was wondering if / when a basic example will be provided. I would like to contribute to this project, but I don't know where to begin. As documentation hasn't been created yet, having an example implementation of some of the features would be greatly appreciated so I could better understand how things should be put together.

Thanks.

The current implementation of node hierarchy can be improved by making graph linear (I don't know if this is the right word)

Current impl:

Randomly allocated nodes:

    Scene
      |
     Node
    /   \
Node      Node
           \
           ....

Considered impl:

Array:

Scene  -  [ Node | Node | Node | ... ]

Currently I'm working on frustum culling; accessing nodes recursively for every operation or in every render frame is not what I want, also it is not effective because you need to switch to another function due to recursion... Maybe making this linear / array would also make exec faster because of cache locality and less memory consumption

• Basic shadowmap
  • Shadowmap for Directional Lights
  • Shadowmap for Spot Lights
  • Shadowmap for Point Lights
• Cascaded shadowmap
  • Shadowmap for Directional Lights
  • Shadowmap for Spot Lights
  • Shadowmap for Point Lights

A shader manager could provide a compiled program or collect combinations of shaders then compile them as program.

This will be used for COMMON profiles/techniques.

• Shader manager
  • Shader manager for common materials; mesh/primitives must use same program/shaders if all attribs, features are same
  • Custom shaders?
• Shader generator
  • Shader generator common materials
    • constant
    • lambert
    • blinn
    • phong
  • Shader generator PBR materials
    • Metallic-Roughness
    • Specular Glossiness

• Multiple render targets
• Off screen [multiple] framebuffers
• Render target manager
• Framebuffer manager

We must define custom material definition format and file, plus a Sharing Language like Google did for Filament:
https://google.github.io/filament/Materials.md.html#overview/coreconcepts or bsl in banshee3d: https://docs.banshee3d.com/Native/bsl.html

File extension could be .gpumat or .mat or .gkmat or .gmat, .effect ...

Desired properties:

• Provide builtin compiler for that material
• Ability to compile at runtime
• Allow multiple passes
• Support all glTF and COLLADA materials

This project will use gpu (this is private repo for now) library as backend. So GPU library may use .gpumat. Also GPU library may provide a shading language or gk could do that.

There's no build system. How do you build gk?

I can contribute Meson build files if that helps.

Today I implemented weighted, blended order independed transparency.

It is time to implement COLLADA's transparency with all opaque modes. At first it seemed difficult to implement but now I think I understand how to implement it. Maybe implementing all opaque modes may be problem with OIT transparency but I will give a try.

it is all about setting blending functions/equations correctly