Gltf Importer

[ykafia]

PR Details

This PR aims to add SharpGLTF as an asset loader for gltf/glb files

Description

• Added a project Stride.Importer.Gltf
• Added the necessary files to handle the gltf importer in Stride.Assets.Model

Related Issue

#603
#336 (to some extent)

Motivation and Context

glTF is a relatively new 3d scene file specification, being able to store way more information than common specifications. It's open source and doesn't need any native binding of any sort. It's also a very well supported file specification across well known 3D softwares (Maya, 3DSMax, Blender, ZBrush)

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My change requires a change to the documentation.
• I have added tests to cover my changes.
• All new and existing tests passed.

Gltf samples working

multi model files are annotated with MM

• 2CylinderEngine
• AlphaBlendModeTest
• AnimatedCube
• AnimatedMorphCube
• AnimatedMorphSphere
• AnimatedTriangle
• AntiqueCamera
• Avocado
• BarramundiFish
• BoomBox
• BoomBoxWithAxes
• Box
• Box With Spaces
• BoxAnimated
• BoxInterleaved
• BoxTextured
• BoxTexturedNonPowerOfTwo
• BoxVertexColors
• BrainStem
• Buggy
• Cameras
• CesiumMan
• CesiumMilkTruck
• ClearCoatTest
• Corset
• Cube
• DamagedHelmet
• Duck
• EnvironmentTest
• FlightHelmet
• Fox
• GearboxAssy
• InterpolationTest
• Lantern
• MaterialsVariantsShoe
• MetalRoughSpheres
• MetalRoughSpheresNoTextures
• MorphPrimitivesTest
• MorphStressTest
• MultiUVTest
• NormalTangentMirrorTest
• NormalTangentTest
• OrientationTest
• ReciprocatingSaw
• RiggedFigure
• RiggedSimple
• SciFiHelmet
• SheenChair
• SheenCloth
• SimpleMeshes
• SimpleMorph
• SimpleSkin
• SimpleSparseAccessor
• SpecGlossVsMetalRough
• Sponza
• Suzanne
• TextureCoordinateTest
• TextureEncodingTest
• TextureSettingsTest
• TextureTransformMultiTest
• TextureTransformTest
• ToyCar
• TransmissionTest
• Triangle
• TriangleWithoutIndices
• TwoSidedPlane
• UnlitTest
• VC
• VertexColorTest
• WaterBottle

[ykafia]

I'm sorry for creating another pull request, i preferred creating it from another branch instead of my master!
Also @xen2 do you have a bit of time to help me with the Stride.Importer.Gltf.csproj parameters i need to add ? I have a bit of trouble understanding how to integrate the project well in Stride.
The issue being : when i compile Stride.Importer.Gltf, dlls of the referenced projects are not found (TFM issue it seems)

[dnfadmin]

All CLA requirements met.

[ykafia]

Known issues so far

• Color vertex models render weirdly (most likely due to a bad VertexDeclaration conversion
• Normal map textures are correctly imported but render fails on some models (DamagedHelmet and Fox). It might be due to the fact that i extract the textures and save them (probably in the wrong format)

[ykafia]

• Importing scenes as a whole, with lights and cameras.
• Multi model scenes import, currently only imports the first model present in the scene. Related to first point. Reason for that is because importing a model in Game Studio is designed to import one object only.
• Only vanilla gltf specification is supported, some extensions can be added though

[Eideren]

I see, I'm pretty sure the fbx importer imports multiple models as one model asset, I think it makes sense for the gltf importer to replicate that behavior ?

[ykafia]

Haven't realized that about fbx but yes it makes sense to replicate this behavior, i think i had a draft somewhere about merging gltf meshes, animations will need more work though

[Eideren]

Oi, again, just create a new issue mate, this is out of scope of this PR.

[Eideren]

Hello @ykafia, how's this PR coming along ? Should I mark this PR as a draft or is this ready to be reviewed ?

[ykafia]

You can mark it as a draft, I will focus my attention on the Assimp PR.

[Aggror]

Would this topic be available for funding from the open collective?

[NicusorN5]

Hey, any progress on this?

[ykafia]

Not much progress except I've made a C# port of MikktSpace tangent generation.

[tebjan]

MikktSpace tangent generation

Shouldn't we use the tangent generation that we already have, because it will fit with the Stride PBR material shaders?

[vjgegenlicht]

Are there any updates on this? Im sure people would support an open collective as mentioned before. It could even be related to the opencollective project about support for multiple animations per file. An update would be nice since we have already prototyped a vvvv vl.stride plugin for GLTF but having it work in stride itself would be much nicer since everyone would benifit.

[ykafia]

Very old PR, should be started again since it's in conflict with the assimp library.