r3d/ROADMAP.md

R3D Roadmap

v0.6

• [ ] Modular State System and On-Demand Resource Loading Replace r3d_state.h with a modular system, split by responsibility, with internal on-demand loading management. For example, introduce a shader cache that loads all shaders lazily when they are first requested during rendering. Apply the same approach to render targets and any other applicable resources. Note: some "details" like details/r3d_light.c or details/r3d_primitives.c could also become modules with lazy loading.

• [ ] Light Module Refactor and Optimization Alongside the modularization of lights:

  • Simplify their update system, including the flag indicating whether shadows need updating.
  • Compute and store transformations (matVP) and AABBs whenever the light's spatial state changes, and retain them for future use.
  • Simplify AABB calculation for spotlights (slightly oversized bounding boxes are acceptable).
  • Revise directional light projection management: remove "scene bounds" from the environment, compute the projection relative to the camera, and use the light's range as the projection distance for directional shadows.
  • Manage the list of visible light indices (from camera) within the light module itself, instead of in r3d_draw.c (see light batch).
  • Add helper functions for testing light influence, e.g. checking if a bounding box is illuminated by a light.
  • Consider adding a real frustum culling by light for shadows, rather than the current crude tests.

• [ ] Draw Call System Refactor Migrate all content from details/r3d_drawcall.h into r3d_draw.c.

• [ ] Unified Draw Call Storage and Index-Based Sorting Replace multiple draw call arrays and in-place object sorting with:

  • a single array containing all draw calls
  • multiple index arrays per category Perform sorting and culling on the index arrays rather than directly on the draw call structures themselves.

v0.7

• [ ] Adding the R3D_InstanceBuffer type to manage instances. See: https://github.com/Bigfoot71/r3d/discussions/121

• [ ] Merge Scene Vertex Shaders Merge all vertex shaders used by the scene module into a single unified vertex shader.

• [ ] Environment API Refactor Replace all environment-related functions with a single R3D_Environment structure, while keeping a global environment state. See: https://github.com/Bigfoot71/r3d/discussions/117

• [ ] Skybox Revision and Reflection Probes Revise the skybox system and add support for reflection probes, including probe blending.

v0.8

• [ ] Add Support for Custom Screen-Space Shaders (Post-Processing) Allow custom shaders to be used in screen-space for post-processing effects.

• [ ] Add Support for Custom Material Shaders Allow custom shaders per material. This will likely require a different approach for deferred vs. forward rendering. Deferred mode will probably offer fewer possibilities than forward mode for custom material shaders.

• [ ] Better logs Add better logs for initialization, shutdown, loading operations, and failures.

v0.9

• [ ] Improve Shadow Map Management Instead of using one shadow map per light, implement an internal batching system with a 2D texture array and Sample2DArray in shaders. Note: This would remove per-light independent shadow map resolutions.

• [ ] Implement Cascaded Shadow Maps (CSM) Add CSM support for directional lights.

• [ ] Make a Wiki Add wiki pages to the Github repository.

Note: v0.9 features are still unsure and/or incomplete.

Ideas (Not Planned Yet)

• After implementing Sampler2DArray for shadow maps, explore using UBOs for lights, but also for environment and matrices/camera data.
• Provide an easy way to configure the number of lights in forward shaders (preferably runtime-configurable).
• Implement a system to save loaded skyboxes together with their generated irradiance and prefiltered textures for later reloading.
• Improve support for shadow/transparency interaction (e.g., colored shadows).