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Fragment Colorv0.12.7
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v0.12.0: 3D scenes, glTF loading and PBR materials

Rafael Beckel
Rafael Beckel
Maintainer

v0.12.0 is the largest release so far. It adds a Scene graph, a glTF model loader, and physically based (PBR) materials.

Full detail is in CHANGELOG.md.

3D scene graph and glTF loading

Section titled “3D scene graph and glTF loading”
  • Scene top-level container implementing Renderable, with a default Camera and Light injected at render time.
  • Scene::load, a glTF 2.0 loader for .gltf and .glb: mesh primitives, per-node transforms flattened into Model matrices, embedded cameras, and KHR_lights_punctual lights.
  • Camera, Light, and Model as first-class scene objects, all absorbed through one generic Scene::add / Pass::add (the SceneObject trait).
  • Higher-level Material + Model objects layered over the existing Shader / Mesh core.
  • Unified Light type with one constructor per kind: directional, point, and spot.
  • Multi-light arrays plus scene-wide ambient, with the per-shader light cap raised from 8 to 32.
  • Loader robustness: face-normal fallback for POSITION-only meshes, and glTF sampler state (wrap modes, filtering) mapped into SamplerOptions.

PBR materials and shading

Section titled “PBR materials and shading”
  • Material::pbr() with metallic-roughness factors and all five glTF texture slots (base color, metallic-roughness, normal, occlusion, emissive).
  • PBR texture sampling routed through the material uniform binding.
  • Lazy texture sources, drained on first render or explicitly via Renderer::load.
  • Alpha modes (Opaque / Mask / Blend) plus double_sided.
  • Automatic back-to-front depth sort for alpha_mode: Blend, so translucent models compose correctly regardless of insertion order.
  • Tangent-space normal mapping via a full TBN transform, with TANGENT from the accessor or a fixed-axis fallback.
  • KHR_texture_transform through Material::uv_transform(offset, scale, rotation).
  • Per-vertex color (COLOR_0) and a second UV set (TEXCOORD_1) as PBR vertex inputs.

Geometry and shaders

Section titled “Geometry and shaders”
  • Vertex::pbr(position) seeds the five-attribute PBR layout with neutral defaults.
  • Mesh indices for indexed draws.
  • Vertex attribute name constants (Vertex::UV0, Vertex::NORMAL, and the rest).

Docs

Section titled “Docs”
  • Texture group restructure: Texture and Mipmap move out of core/ into their own group.

Upgrading

Section titled “Upgrading”
  • Shaders rendered without a material draw with blending off and render both faces. Every pipeline used premultiplied alpha blending before. To blend again, wrap the shader in Material::custom(shader).alpha_mode(AlphaMode::Blend).
  • TextureMipChain becomes Mipmap. Its prepare turns into build, base_size into size, and level_count into count, while format and levels keep their names.

Release notes: GitHub v0.12.0.

Rafael

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