Buffer grow changes:
The exporting of relatevely large data could take a few days, because reallocation of a buffer every time for a few new bytes is overkill. I've introduced standard capacity member for the buffer and growth it by 1.5 times every time. That helps a lot, descrease exporting to a minute (from a few days).
Large file support:
glTF is a json file, all lengths and offsets don't have a type, just numbers, but code was always reading it as uint32, this doesn't work for files bigger than int32 (almost all files we have as an example). So, I've changed it to be reading as size_t. Specification doesn't specify the type for it, so it's not against spec.
Refactors the glTF2 internal classes to more closely reflect the structure
of the actual GLTF2 file format. Adds implementations for reading skins
and animations from GLTF2 files into those structures.
Also provides implementations for converting skins and animations from GLTF
into assimp data structures. Special handling is required for bone weights
since assimp stores vertex-weights-per-bone whereas GLTF2 stores
bone-weights-per-vertex. Only supports keyframed LINEAR animation data;
STEP and CUBICSPLINE is not currently supported.
When I was merging a node’s multiple meshes into that node’s first mesh’s primitives, I was deleting the merged meshes from the node.
However, I wasn’t deleting the merged meshes from the mAsset->meshes Dict, causing the gltf2 export to contain extra unreferenced meshes and duplicate primitives.
This new code adds a new method to LazyDict, which removes the object from it, taking care to update indexes of the subsequent objects. This change also requires that `Ref`s of `Mesh`es (stored in node->meshes) have their indexes updated.
mainly unused parameter and unused function
some parameters are indeed used in a debug built, I used the
(void)(param) trick
warnings reported by clang 4
Samplers are now imported into assimp internal format from textures;
Samplers have defaults as per spec;
Sampler enums are strongly typed with UNSET values;
Samplers are exported properly;
Sampler filters are exported as well;
Samplers are re-used across textures on export
Default sampler values are not written
