Feat add loader for gltf subasset #1071

[zhuxudong]

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[codecov-commenter]

Codecov Report

Base: 44.24% // Head: 41.89% // Decreases project coverage by -2.34% ⚠️

Coverage data is based on head (f316914) compared to base (e3e5b71).
Patch coverage: 4.60% of modified lines in pull request are covered.

Additional details and impacted files

@@             Coverage Diff             @@
##           dev/0.9    #1075      +/-   ##
===========================================
- Coverage    44.24%   41.89%   -2.35%     
===========================================
  Files          342      343       +1     
  Lines        17837    17947     +110     
  Branches      2459     2491      +32     
===========================================
- Hits          7892     7519     -373     
- Misses        9295     9825     +530     
+ Partials       650      603      -47     

Impacted Files	Coverage Δ
packages/loader/src/GLTFLoader.ts	8.10% <0.00%> (-16.90%)	⬇️
packages/loader/src/MaterialLoader.ts	4.65% <0.00%> (-0.23%)	⬇️
packages/loader/src/gltf/GLTFParser.ts	33.33% <0.00%> (ø)
packages/loader/src/gltf/GLTFResource.ts	6.66% <ø> (ø)
packages/loader/src/gltf/parser/AnimationParser.ts	2.40% <0.00%> (-0.17%)	⬇️
packages/loader/src/gltf/parser/BufferParser.ts	17.64% <0.00%> (-1.11%)	⬇️
packages/loader/src/gltf/parser/MaterialParser.ts	3.19% <0.00%> (-0.47%)	⬇️
packages/loader/src/gltf/parser/MeshParser.ts	2.91% <0.00%> (-0.21%)	⬇️
packages/loader/src/gltf/parser/Parser.ts	40.74% <ø> (ø)
packages/loader/src/gltf/parser/ParserContext.ts	11.11% <0.00%> (-22.23%)	⬇️
... and 45 more

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[gz65555]

Sub asset parser should use sub asset loader. You use the cache of parser result if you have loaded the sub asset. Such as:

for(let i = 0;i < textures.length: i++) {
  contex.textures[i] = resourceManager.load(context.url + `q=textures[${i}]`);
}