Create animated mesh with tangents?

[ent1ty]

There is only a method for creating IMesh, how can one create IAnimatedMesh? Is it even possible?

[deadbeef]

Some time ago i had the same problem and i created additional method named "addMeshTangents" in MeshManipulator class. I dunno if its correct but works for me.

Some admin could add it to SVN. Its better than createMeshTangents and works with AnimatedMesh as well as Static.

Code: Select all

void CMeshManipulator::addMeshTangents(IAnimatedMesh* mesh, bool recalculateNormals, bool smooth, bool angleWeighted) const
{
	CSkinnedMesh* meshptr = (CSkinnedMesh*)mesh;

	if (!mesh)
		return;

	const u32 meshBufferCount = mesh->getMeshBufferCount();
	u32 b;

	// now calculate tangents
	for (b=0; b<meshBufferCount; ++b)
	{
		meshptr->getMeshBuffers()[b]->MoveTo_Tangents();

		const u32 vtxCnt = meshptr->getMeshBuffer(b)->getVertexCount();
		const u32 idxCnt = meshptr->getMeshBuffer(b)->getIndexCount();

		u16* idx = meshptr->getMeshBuffer(b)->getIndices();
		video::S3DVertexTangents* v =
			(video::S3DVertexTangents*)meshptr->getMeshBuffer(b)->getVertices();

		if (smooth)
		{
			u32 i;

			for ( i = 0; i!= vtxCnt; ++i )
			{
				if (recalculateNormals)
					v[i].Normal.set( 0.f, 0.f, 0.f );
				v[i].Tangent.set( 0.f, 0.f, 0.f );
				v[i].Binormal.set( 0.f, 0.f, 0.f );
			}

			//Each vertex gets the sum of the tangents and binormals from the faces around it
			for ( i=0; i<idxCnt; i+=3)
			{
				// if this triangle is degenerate, skip it!
				if (v[idx[i+0]].Pos == v[idx[i+1]].Pos || 
					v[idx[i+0]].Pos == v[idx[i+2]].Pos || 
					v[idx[i+1]].Pos == v[idx[i+2]].Pos 
					/*||
					v[idx[i+0]].TCoords == v[idx[i+1]].TCoords || 
					v[idx[i+0]].TCoords == v[idx[i+2]].TCoords || 
					v[idx[i+1]].TCoords == v[idx[i+2]].TCoords */
					) 
					continue;

				//Angle-weighted normals look better, but are slightly more CPU intensive to calculate
				core::vector3df weight(1.f,1.f,1.f);
				if (angleWeighted)
					weight = getAngleWeight(v[i+0].Pos,v[i+1].Pos,v[i+2].Pos);
				core::vector3df localNormal; 
				core::vector3df localTangent;
				core::vector3df localBinormal;

				calculateTangents(
					localNormal,
					localTangent,
					localBinormal,
					v[idx[i+0]].Pos,
					v[idx[i+1]].Pos,
					v[idx[i+2]].Pos,
					v[idx[i+0]].TCoords,
					v[idx[i+1]].TCoords,
					v[idx[i+2]].TCoords);

				if (recalculateNormals)
					v[idx[i+0]].Tangent += localTangent * weight.X;
				v[idx[i+0]].Binormal += localBinormal * weight.X;
				v[idx[i+0]].Normal += localNormal * weight.X;
				
				calculateTangents(
					localNormal,
					localTangent,
					localBinormal,
					v[idx[i+1]].Pos,
					v[idx[i+2]].Pos,
					v[idx[i+0]].Pos,
					v[idx[i+1]].TCoords,
					v[idx[i+2]].TCoords,
					v[idx[i+0]].TCoords);

				if (recalculateNormals)
					v[idx[i+1]].Tangent += localTangent * weight.Y;
				v[idx[i+1]].Binormal += localBinormal * weight.Y;
				v[idx[i+1]].Normal += localNormal * weight.Y;

				calculateTangents(
					localNormal,
					localTangent,
					localBinormal,
					v[idx[i+2]].Pos,
					v[idx[i+0]].Pos,
					v[idx[i+1]].Pos,
					v[idx[i+2]].TCoords,
					v[idx[i+0]].TCoords,
					v[idx[i+1]].TCoords);

				if (recalculateNormals)
					v[idx[i+2]].Tangent += localTangent * weight.Z;
				v[idx[i+2]].Binormal += localBinormal * weight.Z;
				v[idx[i+2]].Normal += localNormal * weight.Z;
			}

			// Normalize the tangents and binormals
			if (recalculateNormals)
			{
				for ( i = 0; i!= vtxCnt; ++i )
					v[i].Normal.normalize();
			}
			for ( i = 0; i!= vtxCnt; ++i )
			{
				v[i].Tangent.normalize();
				v[i].Binormal.normalize();
			}
		}
		else
		{
			core::vector3df localNormal; 
			for (u32 i=0; i<idxCnt; i+=3)
			{
				calculateTangents(
					localNormal,
					v[idx[i+0]].Tangent,
					v[idx[i+0]].Binormal,
					v[idx[i+0]].Pos,
					v[idx[i+1]].Pos,
					v[idx[i+2]].Pos,
					v[idx[i+0]].TCoords,
					v[idx[i+1]].TCoords,
					v[idx[i+2]].TCoords);
				if (recalculateNormals)
					v[idx[i+0]].Normal=localNormal;

				calculateTangents(
					localNormal,
					v[idx[i+1]].Tangent,
					v[idx[i+1]].Binormal,
					v[idx[i+1]].Pos,
					v[idx[i+2]].Pos,
					v[idx[i+0]].Pos,
					v[idx[i+1]].TCoords,
					v[idx[i+2]].TCoords,
					v[idx[i+0]].TCoords);
				if (recalculateNormals)
					v[idx[i+1]].Normal=localNormal;

				calculateTangents(
					localNormal,
					v[idx[i+2]].Tangent,
					v[idx[i+2]].Binormal,
					v[idx[i+2]].Pos,
					v[idx[i+0]].Pos,
					v[idx[i+1]].Pos,
					v[idx[i+2]].TCoords,
					v[idx[i+0]].TCoords,
					v[idx[i+1]].TCoords);
				if (recalculateNormals)
					v[idx[i+2]].Normal=localNormal;
			}
		}
	}
}

[ent1ty]

Nice, thanks

[user-r3]

I'm sorry for digging out a thread that is that old, but I cannot get this to work. All I get is the following message in the console before crashing:

No mesh, or mesh not of skinned mesh type

However, from what I've debugged it is not crashing in this function, neither directly after it, neither in rendering, however I guess there is just something wrong with the mesh created in this function.

Thanks for any help in advance!

[hybrid]

Better don't use this code, but the version that is now in the MeshManipulator class.