Class GltfLoader

Inheritance Relationships

Base Type

Class Documentation

class GltfLoader : public portal::resources::ResourceLoader

Loader for GLTF composite resources.

The GltfLoader handles loading GLTF (.gltf, .glb) files, which are composite resources that contain multiple embedded assets within a single file. A GLTF file can contain:

  • Multiple textures (PNG, JPEG embedded or referenced)

  • Multiple materials (PBR material definitions)

  • Multiple meshes (vertex data, primitives)

  • Multiple scenes (entity hierarchies with transforms)

Composite Resource Pattern:

GLTF loading happens in two phases:

  1. Metadata Enrichment: The database calls enrich_metadata() during filesystem scanning to discover child resources. This parses the GLTF file and creates SourceMetadata entries for each texture, material, mesh, and scene found. These are stored in CompositeMetadata::children.

  2. Resource Loading: When the registry loads the GLTF, load() is called. It iterates through the children and loads each one by dispatching jobs through the registry. The main composite resource tracks these child references.

Usage Example: 

// Loading a GLTF creates a composite with child resources
auto gltf_ref = registry.load<Composite>(STRING_ID("models/character.gltf"));

// Wait for loading to complete
while (!gltf_ref.is_valid()) {
    // Show loading screen
}

// Access child resources through the composite
auto& composite = gltf_ref.get();
auto mesh_ref = composite.get_mesh("character_body");
auto material_ref = composite.get_material("skin_material");
auto scene_ref = composite.get_scene("default_scene");

Dependencies:

See also

enrich_metadata() for the metadata discovery phase

See also

load() for the loading phase

See also

CompositeMetadata for how children are stored

See also

ResourceType::Composite for the composite resource type

Public Functions

GltfLoader(ResourceRegistry &registry, const renderer::vulkan::VulkanContext &context)

Constructor.

Parameters:

  • registry – Reference to ResourceRegistry for loading child resources

  • context – Reference to VulkanContext

virtual Reference<Resource> load(const SourceMetadata &meta, const ResourceSource &source) override

Load a GLTF composite resource and all its children.

Note

This method blocks until the GLTF is parsed and child jobs are dispatched

Note

Child resources load asynchronously on the job system

Parameters:
Returns:

Reference to Composite resource, or nullptr on error

Public Static Functions

static void enrich_metadata(SourceMetadata &meta, const ResourceSource &source)

Enrich metadata by discovering child resources in a GLTF file.

This static method is called during database filesystem scanning. It parses the GLTF file to discover all embedded assets and creates SourceMetadata entries for each child resource. These are stored in CompositeMetadata::children.

Discovered children include:

  • Textures: Each image in the GLTF creates a texture child

  • Materials: Each material creates a material child with texture dependencies

  • Meshes: Each mesh creates a mesh child

  • Scenes: Each scene creates a scene child with mesh/material dependencies

Note

This is called during database scanning, before any loading occurs

Note

The metadata is persisted to .portal-db to avoid re-parsing on startup

Parameters:

Protected Functions

Job load_texture(SourceMetadata texture_meta, const fastgltf::Asset &asset, const fastgltf::Texture &texture) const
Job load_material(SourceMetadata material_meta, const fastgltf::Asset &asset, const fastgltf::Material &material) const
Job load_mesh(SourceMetadata mesh_meta, const fastgltf::Asset &asset, const fastgltf::Mesh &mesh) const
void load_scenes(SourceMetadata meta, const fastgltf::Asset &asset) const

Protected Attributes

const renderer::vulkan::VulkanContext &context
Reference<renderer::vulkan::VulkanPipeline> g_transparent_pipeline
Reference<renderer::vulkan::VulkanPipeline> g_color_pipeline

Protected Static Functions

static fastgltf::Asset load_asset(const SourceMetadata &meta, fastgltf::GltfDataGetter &data)
static std::pair<SourceMetadata, std::unique_ptr<ResourceSource>> find_image_source(const std::filesystem::path &base_name, const std::filesystem::path &base_path, const fastgltf::Asset &asset, const fastgltf::Texture &texture)