Set up normals or UV on the Cube and Add Material to 3D Entities

Aspose.3D for .NET offers to manage normals and UV on the geometric shapes. A mesh stores the key properties for every vertex are its position in space and its normal, a vector perpendicular to the original surface. The normal is major to shading counts. The normals should be unit vectors. Most mesh formats also support some form of UV coordinates which are a separate 2d representation of the mesh “unfolded” to show what portion of a 2-dimensional texture map to apply to different polygons of the mesh.

The Mesh class object is being used in the code. We can create a Mesh class object as narrated there and then point node to the Mesh geometry by Creating a 3D Scene.

Create Normal Vectors

To have a good visual look on lighting, we need to specify normals information for each vertex, to have a better details, we can also use normal and diffuse map (sure you can use shadow / specular map) to perform per-pixel normal/color. A per-vertex information like normal or vertex color is achieved by VertexElement. In Aspose.3D we can map extra information to control points/polygon vertex/polygon/edge, a sample to define normals for vertex:

	// For complete examples and data files, please go to https://github.com/aspose-3d/Aspose.3D-for-.NET
	// Raw normal data
	Vector4[] normals = new Vector4[]
	{
	new Vector4(-0.577350258,-0.577350258, 0.577350258, 1.0),
	new Vector4( 0.577350258,-0.577350258, 0.577350258, 1.0),
	new Vector4( 0.577350258, 0.577350258, 0.577350258, 1.0),
	new Vector4(-0.577350258, 0.577350258, 0.577350258, 1.0),
	new Vector4(-0.577350258,-0.577350258,-0.577350258, 1.0),
	new Vector4( 0.577350258,-0.577350258,-0.577350258, 1.0),
	new Vector4( 0.577350258, 0.577350258,-0.577350258, 1.0),
	new Vector4(-0.577350258, 0.577350258,-0.577350258, 1.0)
	};

	// Call Common class create mesh using polygon builder method to set mesh instance
	Mesh mesh = Common.CreateMeshUsingPolygonBuilder();

	VertexElementNormal elementNormal = mesh.CreateElement(VertexElementType.Normal, MappingMode.ControlPoint, ReferenceMode.Direct) as VertexElementNormal;
	// Copy the data to the vertex element
	elementNormal.Data.AddRange(normals);

view raw Examples-CSharp-Geometry-and-Hierarchy-SetupNormalsOnCube-SetupNormalsOnCube.cs hosted with ❤ by GitHub

The 8 normal vectors are mapped to 8 control points directly, in the next example, we’ll demonstrate a bit more complex scenario.

Create UV Coordinates

Here,we only defined 4 UV coordinates, but applied them to 24 polygon vertices (6 face * 4 vertex per polygon) by using indices. The Aspose.3D provides 5 mapping modes:

ControlPoint - each data is mapped to the control point of the geometry.
PolygonVertex - the data is mapped to the polygon’s vertex.
Polygon - the data is mapped to the polygon.
Edge - the data is mapped to the edge.
AllSame - one data mapped to the whole geometry.

	// For complete examples and data files, please go to https://github.com/aspose-3d/Aspose.3D-for-.NET
	// UVs
	Vector4[] uvs = new Vector4[]
	{
	new Vector4( 0.0, 1.0,0.0, 1.0),
	new Vector4( 1.0, 0.0,0.0, 1.0),
	new Vector4( 0.0, 0.0,0.0, 1.0),
	new Vector4( 1.0, 1.0,0.0, 1.0)
	};

	// Indices of the uvs per each polygon
	int[] uvsId = new int[]
	{
	0,1,3,2,2,3,5,4,4,5,7,6,6,7,9,8,1,10,11,3,12,0,2,13
	};

	// Call Common class create mesh using polygon builder method to set mesh instance
	Mesh mesh = Common.CreateMeshUsingPolygonBuilder();

	// Create UVset
	VertexElementUV elementUV = mesh.CreateElementUV(TextureMapping.Diffuse, MappingMode.PolygonVertex, ReferenceMode.IndexToDirect);
	// Copy the data to the UV vertex element
	elementUV.Data.AddRange(uvs);
	elementUV.Indices.AddRange(uvsId);

view raw Examples-CSharp-Geometry-and-Hierarchy-SetupUVOnCube-SetupUVOnCube.cs hosted with ❤ by GitHub

Add Materials to 3D Objects

Aspose.3D for .NET allows developers to use shading algorithm for accurate shading and highlights. The Phong has several map inputs which we can use to mask the effect to the node. Physically Based Rendering (PBR) takes some physical properties of objects into account, such an approach provides the appearance of materials as in the real world.

Phong Material with Texture for Cube

When the UV coordinates are ready to use, we can apply a texture on the surface of mesh by using material. Only vertex color cannot describe the details of surface, that’s what materials used for. Here’s an example to attach a Phong material to the cube node:

	// For complete examples and data files, please go to https://github.com/aspose-3d/Aspose.3D-for-.NET
	// Initialize scene object
	Scene scene = new Scene();

	// Initialize cube node object
	Node cubeNode = new Node("cube");

	// Call Common class create mesh using polygon builder method to set mesh instance
	Mesh mesh = Common.CreateMeshUsingPolygonBuilder();

	// Point node to the mesh
	cubeNode.Entity = mesh;

	// Add cube to the scene
	scene.RootNode.ChildNodes.Add(cubeNode);

	// Initiallize PhongMaterial object
	PhongMaterial mat = new PhongMaterial();

	// Initiallize Texture object
	Texture diffuse = new Texture();

	// The path to the documents directory.

	// Set local file path
	diffuse.FileName = RunExamples.GetOutputFilePath("surface.dds");

	// Set Texture of the material
	mat.SetTexture("DiffuseColor", diffuse);

	// Embed raw content data to FBX (only for FBX and optional)
	// Set file name
	diffuse.FileName = "embedded-texture.png";
	// Set binary content
	diffuse.Content = File.ReadAllBytes(RunExamples.GetDataFilePath("aspose-logo.jpg"));

	// Set color
	mat.SpecularColor = new Vector3(Color.Red);

	// Set brightness
	mat.Shininess = 100;

	// Set material property of the cube object
	cubeNode.Material = mat;

	// Save 3D scene in the supported file formats
	scene.Save("MaterialToCube.fbx");

view raw Examples-CSharp-Geometry-and-Hierarchy-MaterialToCube-AddMaterialToCube.cs hosted with ❤ by GitHub

We specified the diffuse texture mapping, and a specular color with a shininess parameter.

Apply Physically Based Rendering (PBR) Material to a Box

PBR plays a key role for the game engine visuals, with its efficient and realistic rendering of interactions between light and surface via attenuation of the brightness and scattering of reflected light. Developers can use Aspose.3D API to apply PBR material to 3D objects in a scene. This code example demonstrates to how to create a Box object, and then apply the PBR material.

.NET, C#

 // initialize a scene

Scene scene = new Scene();

// initialize PBR material object

PbrMaterial mat = new PbrMaterial();

// an almost metal material

mat.MetallicFactor = 0.9;

// material surface is very rough

mat.RoughnessFactor = 0.9;

// create a box to which the material will be applied

var boxNode = scene.RootNode.CreateChildNode("box", new Box());

boxNode.Material = mat;

// save 3d scene into STL format

scene.Save(@"C:\3D\PBR_Material_Box_Out.stl", FileFormat.STLASCII);

Adding Transformation to the Node