private GLTFNode ExportMesh(BabylonMesh babylonMesh, GLTF gltf, GLTFNode gltfParentNode, BabylonScene babylonScene)
{
RaiseMessage("GLTFExporter.Mesh | Export mesh named: " + babylonMesh.name, 1);
// --------------------------
// ---------- Node ----------
// --------------------------
RaiseMessage("GLTFExporter.Mesh | Node", 2);
// Node
var gltfNode = new GLTFNode();
gltfNode.name = babylonMesh.name;
gltfNode.index = gltf.NodesList.Count;
gltf.NodesList.Add(gltfNode);
// Hierarchy
if (gltfParentNode != null)
{
RaiseMessage("GLTFExporter.Mesh | Add " + babylonMesh.name + " as child to " + gltfParentNode.name, 3);
gltfParentNode.ChildrenList.Add(gltfNode.index);
}
else
{
// It's a root node
// Only root nodes are listed in a gltf scene
RaiseMessage("GLTFExporter.Mesh | Add " + babylonMesh.name + " as root node to scene", 3);
gltf.scenes[0].NodesList.Add(gltfNode.index);
}
// Transform
gltfNode.translation = babylonMesh.position;
// TODO - Choose between this method and the extra root node
// Switch from left to right handed coordinate system
//gltfNode.translation[0] *= -1;
if (babylonMesh.rotationQuaternion != null)
{
gltfNode.rotation = babylonMesh.rotationQuaternion;
}
else
{
// Convert rotation vector to quaternion
BabylonVector3 rotationVector3 = new BabylonVector3
{
X = babylonMesh.rotation[0],
Y = babylonMesh.rotation[1],
Z = babylonMesh.rotation[2]
};
gltfNode.rotation = rotationVector3.toQuaternionGltf().ToArray();
}
gltfNode.scale = babylonMesh.scaling;
// --------------------------
// --- Mesh from babylon ----
// --------------------------
if (babylonMesh.positions == null)
{
RaiseMessage("GLTFExporter.Mesh | Mesh is a dummy", 2);
return(gltfNode);
}
RaiseMessage("GLTFExporter.Mesh | Mesh from babylon", 2);
// Retreive general data from babylon mesh
int nbVertices = babylonMesh.positions.Length / 3;
bool hasUV = babylonMesh.uvs != null && babylonMesh.uvs.Length > 0;
bool hasUV2 = babylonMesh.uvs2 != null && babylonMesh.uvs2.Length > 0;
bool hasColor = babylonMesh.colors != null && babylonMesh.colors.Length > 0;
RaiseMessage("GLTFExporter.Mesh | nbVertices=" + nbVertices, 3);
RaiseMessage("GLTFExporter.Mesh | hasUV=" + hasUV, 3);
RaiseMessage("GLTFExporter.Mesh | hasUV2=" + hasUV2, 3);
RaiseMessage("GLTFExporter.Mesh | hasColor=" + hasColor, 3);
// Retreive vertices data from babylon mesh
List <GLTFGlobalVertex> globalVertices = new List <GLTFGlobalVertex>();
for (int indexVertex = 0; indexVertex < nbVertices; indexVertex++)
{
GLTFGlobalVertex globalVertex = new GLTFGlobalVertex();
globalVertex.Position = createIPoint3(babylonMesh.positions, indexVertex);
// Switch from left to right handed coordinate system
//globalVertex.Position.X *= -1;
globalVertex.Normal = createIPoint3(babylonMesh.normals, indexVertex);
if (hasUV)
{
globalVertex.UV = createIPoint2(babylonMesh.uvs, indexVertex);
// For glTF, the origin of the UV coordinates (0, 0) corresponds to the upper left corner of a texture image
// While for Babylon, it corresponds to the lower left corner of a texture image
globalVertex.UV.Y = 1 - globalVertex.UV.Y;
}
if (hasUV2)
{
globalVertex.UV2 = createIPoint2(babylonMesh.uvs2, indexVertex);
// For glTF, the origin of the UV coordinates (0, 0) corresponds to the upper left corner of a texture image
// While for Babylon, it corresponds to the lower left corner of a texture image
globalVertex.UV2.Y = 1 - globalVertex.UV2.Y;
}
if (hasColor)
{
globalVertex.Color = createIPoint4(babylonMesh.colors, indexVertex).ToArray();
}
globalVertices.Add(globalVertex);
}
// Retreive indices from babylon mesh
List <ushort> babylonIndices = new List <ushort>();
babylonIndices = babylonMesh.indices.ToList().ConvertAll(new Converter <int, ushort>(n => (ushort)n));
// For triangle primitives in gltf, the front face has a counter-clockwise (CCW) winding order
// Swap face side
//for (int i = 0; i < babylonIndices.Count; i += 3)
//{
// var tmp = babylonIndices[i];
// babylonIndices[i] = babylonIndices[i + 2];
// babylonIndices[i + 2] = tmp;
//}
// --------------------------
// ------- Init glTF --------
// --------------------------
RaiseMessage("GLTFExporter.Mesh | Init glTF", 2);
// Mesh
var gltfMesh = new GLTFMesh {
name = babylonMesh.name
};
gltfMesh.index = gltf.MeshesList.Count;
gltf.MeshesList.Add(gltfMesh);
gltfNode.mesh = gltfMesh.index;
gltfMesh.gltfNode = gltfNode;
// Buffer
var buffer = new GLTFBuffer
{
uri = gltfMesh.name + ".bin"
};
buffer.index = gltf.BuffersList.Count;
gltf.BuffersList.Add(buffer);
// BufferView - Scalar
var bufferViewScalar = new GLTFBufferView
{
name = "bufferViewScalar",
buffer = buffer.index,
Buffer = buffer
};
bufferViewScalar.index = gltf.BufferViewsList.Count;
gltf.BufferViewsList.Add(bufferViewScalar);
// BufferView - Vector3
var bufferViewFloatVec3 = new GLTFBufferView
{
name = "bufferViewFloatVec3",
buffer = buffer.index,
Buffer = buffer,
byteOffset = 0,
byteStride = 12 // Field only defined for buffer views that contain vertex attributes. A vertex needs 3 * 4 bytes
};
bufferViewFloatVec3.index = gltf.BufferViewsList.Count;
gltf.BufferViewsList.Add(bufferViewFloatVec3);
// BufferView - Vector4
GLTFBufferView bufferViewFloatVec4 = null;
if (hasColor)
{
bufferViewFloatVec4 = new GLTFBufferView
{
name = "bufferViewFloatVec4",
buffer = buffer.index,
Buffer = buffer,
byteOffset = 0,
byteStride = 16 // Field only defined for buffer views that contain vertex attributes. A vertex needs 4 * 4 bytes
};
bufferViewFloatVec4.index = gltf.BufferViewsList.Count;
gltf.BufferViewsList.Add(bufferViewFloatVec4);
}
// BufferView - Vector2
GLTFBufferView bufferViewFloatVec2 = null;
if (hasUV || hasUV2)
{
bufferViewFloatVec2 = new GLTFBufferView
{
name = "bufferViewFloatVec2",
buffer = buffer.index,
Buffer = buffer,
byteStride = 8 // Field only defined for buffer views that contain vertex attributes. A vertex needs 2 * 4 bytes
};
bufferViewFloatVec2.index = gltf.BufferViewsList.Count;
gltf.BufferViewsList.Add(bufferViewFloatVec2);
}
// --------------------------
// ---- glTF primitives -----
// --------------------------
RaiseMessage("GLTFExporter.Mesh | glTF primitives", 2);
var meshPrimitives = new List <GLTFMeshPrimitive>();
// Global vertices are sorted per submesh
var globalVerticesSubMeshes = new List <List <GLTFGlobalVertex> >();
// In gltf, indices of each mesh primitive are 0-based (ie: min value is 0)
// Thus, the gltf indices list is a concatenation of sub lists all 0-based
// Example for 2 triangles, each being a submesh:
// babylonIndices = {0,1,2, 3,4,5} gives as result gltfIndicies = {0,1,2, 0,1,2}
var gltfIndices = new List <ushort>();
foreach (BabylonSubMesh babylonSubMesh in babylonMesh.subMeshes)
{
// --------------------------
// ------ SubMesh data ------
// --------------------------
List <GLTFGlobalVertex> globalVerticesSubMesh = globalVertices.GetRange(babylonSubMesh.verticesStart, babylonSubMesh.verticesCount);
globalVerticesSubMeshes.Add(globalVerticesSubMesh);
List <ushort> _indices = babylonIndices.GetRange(babylonSubMesh.indexStart, babylonSubMesh.indexCount);
// Indices of this submesh / primitive are updated to be 0-based
var minIndiceValue = _indices.Min(); // Should be equal to babylonSubMesh.indexStart
for (int indexIndice = 0; indexIndice < _indices.Count; indexIndice++)
{
_indices[indexIndice] -= minIndiceValue;
}
gltfIndices.AddRange(_indices);
// --------------------------
// -- Init glTF primitive ---
// --------------------------
// MeshPrimitive
var meshPrimitive = new GLTFMeshPrimitive
{
attributes = new Dictionary <string, int>()
};
meshPrimitives.Add(meshPrimitive);
// Accessor - Indices
var accessorIndices = new GLTFAccessor
{
name = "accessorIndices",
bufferView = bufferViewScalar.index,
BufferView = bufferViewScalar,
componentType = GLTFAccessor.ComponentType.UNSIGNED_SHORT,
type = GLTFAccessor.TypeEnum.SCALAR.ToString()
};
accessorIndices.index = gltf.AccessorsList.Count;
gltf.AccessorsList.Add(accessorIndices);
meshPrimitive.indices = accessorIndices.index;
// Accessor - Positions
var accessorPositions = new GLTFAccessor
{
name = "accessorPositions",
bufferView = bufferViewFloatVec3.index,
BufferView = bufferViewFloatVec3,
componentType = GLTFAccessor.ComponentType.FLOAT,
type = GLTFAccessor.TypeEnum.VEC3.ToString(),
min = new float[] { float.MaxValue, float.MaxValue, float.MaxValue },
max = new float[] { float.MinValue, float.MinValue, float.MinValue }
};
accessorPositions.index = gltf.AccessorsList.Count;
gltf.AccessorsList.Add(accessorPositions);
meshPrimitive.attributes.Add(GLTFMeshPrimitive.Attribute.POSITION.ToString(), accessorPositions.index);
// Accessor - Normals
var accessorNormals = new GLTFAccessor
{
name = "accessorNormals",
bufferView = bufferViewFloatVec3.index,
BufferView = bufferViewFloatVec3,
componentType = GLTFAccessor.ComponentType.FLOAT,
type = GLTFAccessor.TypeEnum.VEC3.ToString()
};
accessorNormals.index = gltf.AccessorsList.Count;
gltf.AccessorsList.Add(accessorNormals);
meshPrimitive.attributes.Add(GLTFMeshPrimitive.Attribute.NORMAL.ToString(), accessorNormals.index);
// Accessor - Colors
GLTFAccessor accessorColors = null;
if (hasColor)
{
accessorColors = new GLTFAccessor
{
name = "accessorColors",
bufferView = bufferViewFloatVec4.index,
BufferView = bufferViewFloatVec4,
componentType = GLTFAccessor.ComponentType.FLOAT,
type = GLTFAccessor.TypeEnum.VEC4.ToString()
};
accessorColors.index = gltf.AccessorsList.Count;
gltf.AccessorsList.Add(accessorColors);
meshPrimitive.attributes.Add(GLTFMeshPrimitive.Attribute.COLOR_0.ToString(), accessorColors.index);
}
// Accessor - UV
GLTFAccessor accessorUVs = null;
if (hasUV)
{
accessorUVs = new GLTFAccessor
{
name = "accessorUVs",
bufferView = bufferViewFloatVec2.index,
BufferView = bufferViewFloatVec2,
componentType = GLTFAccessor.ComponentType.FLOAT,
type = GLTFAccessor.TypeEnum.VEC2.ToString()
};
accessorUVs.index = gltf.AccessorsList.Count;
gltf.AccessorsList.Add(accessorUVs);
meshPrimitive.attributes.Add(GLTFMeshPrimitive.Attribute.TEXCOORD_0.ToString(), accessorUVs.index);
}
// Accessor - UV2
GLTFAccessor accessorUV2s = null;
if (hasUV2)
{
accessorUV2s = new GLTFAccessor
{
name = "accessorUV2s",
bufferView = bufferViewFloatVec2.index,
BufferView = bufferViewFloatVec2,
componentType = GLTFAccessor.ComponentType.FLOAT,
type = GLTFAccessor.TypeEnum.VEC2.ToString()
};
accessorUV2s.index = gltf.AccessorsList.Count;
gltf.AccessorsList.Add(accessorUV2s);
meshPrimitive.attributes.Add(GLTFMeshPrimitive.Attribute.TEXCOORD_1.ToString(), accessorUV2s.index);
}
// --------------------------
// - Update glTF primitive --
// --------------------------
RaiseMessage("GLTFExporter.Mesh | Mesh as glTF", 3);
// Material
if (babylonMesh.materialId != null)
{
// Retreive the babylon material
var babylonMaterialId = babylonMesh.materialId;
var babylonMaterials = new List <BabylonMaterial>(babylonScene.materials);
var babylonMaterial = babylonMaterials.Find(_babylonMaterial => _babylonMaterial.id == babylonMaterialId);
if (babylonMaterial == null)
{
// It's a multi material
var babylonMultiMaterials = new List <BabylonMultiMaterial>(babylonScene.multiMaterials);
var babylonMultiMaterial = babylonMultiMaterials.Find(_babylonMultiMaterial => _babylonMultiMaterial.id == babylonMesh.materialId);
babylonMaterialId = babylonMultiMaterial.materials[babylonSubMesh.materialIndex];
babylonMaterial = babylonMaterials.Find(_babylonMaterial => _babylonMaterial.id == babylonMaterialId);
}
// Update primitive material index
var indexMaterial = babylonMaterialsToExport.FindIndex(_babylonMaterial => _babylonMaterial == babylonMaterial);
if (indexMaterial == -1)
{
// Store material for exportation
indexMaterial = babylonMaterialsToExport.Count;
babylonMaterialsToExport.Add(babylonMaterial);
}
meshPrimitive.material = indexMaterial;
// TODO - Add and retreive info from babylon material
meshPrimitive.mode = GLTFMeshPrimitive.FillMode.TRIANGLES;
}
// Update min and max vertex position for each component (X, Y, Z)
globalVerticesSubMesh.ForEach((globalVertex) =>
{
var positionArray = new float[] { globalVertex.Position.X, globalVertex.Position.Y, globalVertex.Position.Z };
for (int indexComponent = 0; indexComponent < positionArray.Length; indexComponent++)
{
if (positionArray[indexComponent] < accessorPositions.min[indexComponent])
{
accessorPositions.min[indexComponent] = positionArray[indexComponent];
}
if (positionArray[indexComponent] > accessorPositions.max[indexComponent])
{
accessorPositions.max[indexComponent] = positionArray[indexComponent];
}
}
});
// Update byte length and count of accessors, bufferViews and buffers
// Scalar
AddElementsToAccessor(accessorIndices, _indices.Count);
// Vector3
AddElementsToAccessor(accessorPositions, globalVerticesSubMesh.Count);
AddElementsToAccessor(accessorNormals, globalVerticesSubMesh.Count);
// Vector4
if (hasColor)
{
AddElementsToAccessor(accessorColors, globalVerticesSubMesh.Count);
}
// Vector2
if (hasUV)
{
AddElementsToAccessor(accessorUVs, globalVerticesSubMesh.Count);
}
if (hasUV2)
{
AddElementsToAccessor(accessorUV2s, globalVerticesSubMesh.Count);
}
}
gltfMesh.primitives = meshPrimitives.ToArray();
// Update byte offset of bufferViews
GLTFBufferView lastBufferView = null;
gltf.BufferViewsList.FindAll(bufferView => bufferView.buffer == buffer.index).ForEach(bufferView =>
{
if (lastBufferView != null)
{
bufferView.byteOffset = lastBufferView.byteOffset + lastBufferView.byteLength;
}
lastBufferView = bufferView;
});
// --------------------------
// --------- Saving ---------
// --------------------------
string outputBinaryFile = Path.Combine(gltf.OutputPath, gltfMesh.name + ".bin");
RaiseMessage("GLTFExporter.Mesh | Saving " + outputBinaryFile, 2);
// Write data to binary file
using (BinaryWriter writer = new BinaryWriter(File.Open(outputBinaryFile, FileMode.Create)))
{
// BufferView - Scalar
gltfIndices.ForEach(n => writer.Write(n));
// BufferView - Vector3
globalVerticesSubMeshes.ForEach(globalVerticesSubMesh =>
{
List <float> vertices = globalVerticesSubMesh.SelectMany(v => new[] { v.Position.X, v.Position.Y, v.Position.Z }).ToList();
vertices.ForEach(n => writer.Write(n));
List <float> normals = globalVerticesSubMesh.SelectMany(v => new[] { v.Normal.X, v.Normal.Y, v.Normal.Z }).ToList();
normals.ForEach(n => writer.Write(n));
});
// BufferView - Vector4
globalVerticesSubMeshes.ForEach(globalVerticesSubMesh =>
{
if (hasColor)
{
List <float> colors = globalVerticesSubMesh.SelectMany(v => new[] { v.Color[0], v.Color[1], v.Color[2], v.Color[3] }).ToList();
colors.ForEach(n => writer.Write(n));
}
});
// BufferView - Vector2
globalVerticesSubMeshes.ForEach(globalVerticesSubMesh =>
{
if (hasUV)
{
List <float> uvs = globalVerticesSubMesh.SelectMany(v => new[] { v.UV.X, v.UV.Y }).ToList();
uvs.ForEach(n => writer.Write(n));
}
if (hasUV2)
{
List <float> uvs2 = globalVerticesSubMesh.SelectMany(v => new[] { v.UV2.X, v.UV2.Y }).ToList();
uvs2.ForEach(n => writer.Write(n));
}
});
}
return(gltfNode);
}
// TODO - Test if ok with a gltf viewer working with custom camera (babylon loader/sandbox doesn't load them)
private GLTFCamera ExportCamera(BabylonCamera babylonCamera, GLTF gltf, GLTFNode gltfParentNode)
{
RaiseMessage("GLTFExporter.Camera | Export camera named: " + babylonCamera.name, 1);
// --------------------------
// ---------- Node ----------
// --------------------------
RaiseMessage("GLTFExporter.Camera | Node", 2);
// Node
var gltfNode = new GLTFNode();
gltfNode.name = babylonCamera.name;
gltfNode.index = gltf.NodesList.Count;
gltf.NodesList.Add(gltfNode);
// Hierarchy
if (gltfParentNode != null)
{
RaiseMessage("GLTFExporter.Camera | Add " + babylonCamera.name + " as child to " + gltfParentNode.name, 3);
gltfParentNode.ChildrenList.Add(gltfNode.index);
}
else
{
// It's a root node
// Only root nodes are listed in a gltf scene
RaiseMessage("GLTFExporter.Camera | Add " + babylonCamera.name + " as root node to scene", 3);
gltf.scenes[0].NodesList.Add(gltfNode.index);
}
// Transform
gltfNode.translation = babylonCamera.position;
// Switch from left to right handed coordinate system
//gltfNode.translation[0] *= -1;
if (babylonCamera.rotationQuaternion != null)
{
gltfNode.rotation = babylonCamera.rotationQuaternion;
}
else
{
// Convert rotation vector to quaternion
BabylonVector3 rotationVector3 = new BabylonVector3
{
X = babylonCamera.rotation[0],
Y = babylonCamera.rotation[1],
Z = babylonCamera.rotation[2]
};
gltfNode.rotation = rotationVector3.toQuaternionGltf().ToArray();
}
// No scaling defined for babylon camera. Use identity instead.
gltfNode.scale = new float[3] {
1, 1, 1
};
// --- prints ---
RaiseMessage("GLTFExporter.Camera | babylonCamera data", 2);
RaiseMessage("GLTFExporter.Camera | babylonCamera.type=" + babylonCamera.type, 3);
RaiseMessage("GLTFExporter.Camera | babylonCamera.fov=" + babylonCamera.fov, 3);
RaiseMessage("GLTFExporter.Camera | babylonCamera.maxZ=" + babylonCamera.maxZ, 3);
RaiseMessage("GLTFExporter.Camera | babylonCamera.minZ=" + babylonCamera.minZ, 3);
// --------------------------
// ------- gltfCamera -------
// --------------------------
RaiseMessage("GLTFExporter.Camera | create gltfCamera", 2);
// Camera
var gltfCamera = new GLTFCamera {
name = babylonCamera.name
};
gltfCamera.index = gltf.CamerasList.Count;
gltf.CamerasList.Add(gltfCamera);
gltfNode.camera = gltfCamera.index;
gltfCamera.gltfNode = gltfNode;
// Camera type
switch (babylonCamera.mode)
{
case (BabylonCamera.CameraMode.ORTHOGRAPHIC_CAMERA):
var gltfCameraOrthographic = new GLTFCameraOrthographic();
gltfCameraOrthographic.xmag = 1; // TODO - How to retreive value from babylon? xmag:The floating-point horizontal magnification of the view
gltfCameraOrthographic.ymag = 1; // TODO - How to retreive value from babylon? ymag:The floating-point vertical magnification of the view
gltfCameraOrthographic.zfar = babylonCamera.maxZ;
gltfCameraOrthographic.znear = babylonCamera.minZ;
gltfCamera.type = GLTFCamera.CameraType.orthographic.ToString();
gltfCamera.orthographic = gltfCameraOrthographic;
break;
case (BabylonCamera.CameraMode.PERSPECTIVE_CAMERA):
var gltfCameraPerspective = new GLTFCameraPerspective();
gltfCameraPerspective.aspectRatio = null; // 0.8f; // TODO - How to retreive value from babylon? The aspect ratio in babylon is computed based on the engine rather than set on a camera (aspectRatio = _gl.drawingBufferWidth / _gl.drawingBufferHeight)
gltfCameraPerspective.yfov = babylonCamera.fov; // WARNING - Babylon camera fov mode is assumed to be vertical (FOVMODE_VERTICAL_FIXED)
gltfCameraPerspective.zfar = babylonCamera.maxZ;
gltfCameraPerspective.znear = babylonCamera.minZ;
gltfCamera.type = GLTFCamera.CameraType.perspective.ToString();
gltfCamera.perspective = gltfCameraPerspective;
break;
default:
RaiseError("GLTFExporter.Camera | camera mode not found");
break;
}
return(gltfCamera);
}