3d-games

# 3D Game Development > Principles for 3D game systems. --- ## 1. Rendering Pipeline ### Stages ``` 1. Vertex Processing → Transform geometry 2. Rasterization → Convert to pixels 3. Fragment Processing → Color pixels 4. Output → To screen ``` ### Optimization Principles | Technique | Purpose | |-----------|---------| | **Frustum culling** | Don't render off-screen | | **Occlusion culling** | Don't render hidden | | **LOD** | Less detail at distance | | **Batching** | Combine draw calls | --- ## 2. Shader Principles ### Shader Types | Type | Purpose | |------|---------| | **Vertex** | Position, normals | | **Fragment/Pixel** | Color, lighting | | **Compute** | General computation | ### When to Write Custom Shaders - Special effects (water, fire, portals) - Stylized rendering (toon, sketch) - Performance optimization - Unique visual identity --- ## 3. 3D Physics ### Collision Shapes | Shape | Use Case | |-------|----------| | **Box** | Buildings, crates | | **Sphere** | Balls, quick checks | | **Capsule** | Characters | | **Mesh** | Terrain (expensive) | ### Principles - Simple colliders, complex visuals - Layer-based filtering - Raycasting for line-of-sight --- ## 4. Camera Systems ### Camera Types | Type | Use | |------|-----| | **Third-person** | Action, adventure | | **First-person** | Immersive, FPS | | **Isometric** | Strategy, RPG | | **Orbital** | Inspection, editors | ### Camera Feel - Smooth following (lerp) - Collision avoidance - Look-ahead for movement - FOV changes for speed --- ## 5. Lighting ### Light Types | Type | Use | |------|-----| | **Directional** | Sun, moon | | **Point** | Lamps, torches | | **Spot** | Flashlight, stage | | **Ambient** | Base illumination | ### Performance Consideration - Real-time shadows are expensive - Bake when possible - Shadow cascades for large worlds --- ## 6. Level of Detail (LOD) ### LOD Strategy | Distance | Model | |----------|-------| | Near | Full detail | | Medium | 50% triangles | | Far | 25% or billboard | --- ## 7. Anti-Patterns | ❌ Don't | ✅ Do | |----------|-------| | Mesh colliders everywhere | Simple shapes | | Real-time shadows on mobile | Baked or blob shadows | | One LOD for all distances | Distance-based LOD | | Unoptimized shaders | Profile and simplify | --- > **Remember:** 3D is about illusion. Create the impression of detail, not the detail itself.