如何：创建三维场景
更新：2007 年 11 月
本示例演示如何创建类似于已旋转的平板纸的三维对象。利用 Viewport3D 以及下面的组件创建这一简单的三维场景：
使用 PerspectiveCamera 创建一个照相机。该照相机指定三维场景的哪个部分是可见的。
创建一个网格，以使用 GeometryModel3D 的 Geometry 属性指定三维对象（平板纸）的形状。
使用 GeometryModel3D 的 Material 属性指定要在对象表面显示的材料（本示例中是线性渐变）。
使用 DirectionalLight 创建在对象上发光的光源。
示例
下面的代码演示如何以 XAML 创建三维场景。
<Page xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml" >
<DockPanel>
<Viewbox>
<Canvas Width="321" Height="201">
<!-- The Viewport3D provides a rendering surface for 3-D visual content. -->
<Viewport3D ClipToBounds="True" Width="150" Height="150" Canvas.Left="0" Canvas.Top="10">
<!-- Defines the camera used to view the 3D object. -->
<Viewport3D.Camera>
<PerspectiveCamera Position="0,0,2" LookDirection="0,0,-1" FieldOfView="60" />
</Viewport3D.Camera>
<!-- The ModelVisual3D children contain the 3D models -->
<Viewport3D.Children>
<!-- This ModelVisual3D defines the light cast in the scene. Without light, the 3D
object cannot be seen. Also, the direction of the lights affect shadowing. If desired,
you can create multiple lights with different colors that shine from different directions. -->
<ModelVisual3D>
<ModelVisual3D.Content>
<DirectionalLight Color="#FFFFFF" Direction="-0.612372,-0.5,-0.612372" />
</ModelVisual3D.Content>
</ModelVisual3D>
<ModelVisual3D>
<ModelVisual3D.Content>
<GeometryModel3D>
<!-- The geometry specifes the shape of the 3D plane. In this sample, a flat sheet is created. -->
<GeometryModel3D.Geometry>
<MeshGeometry3D
TriangleIndices="0,1,2 3,4,5 "
Normals="0,0,1 0,0,1 0,0,1 0,0,1 0,0,1 0,0,1 "
TextureCoordinates="0,0 1,0 1,1 1,1 0,1 0,0 "
Positions="-0.5,-0.5,0.5 0.5,-0.5,0.5 0.5,0.5,0.5 0.5,0.5,0.5 -0.5,0.5,0.5 -0.5,-0.5,0.5 " />
</GeometryModel3D.Geometry>
<!-- The material specifies the material applied to the 3D object. In this sample a linear gradient
covers the surface of the 3D object.-->
<GeometryModel3D.Material>
<MaterialGroup>
<DiffuseMaterial>
<DiffuseMaterial.Brush>
<LinearGradientBrush StartPoint="0,0.5" EndPoint="1,0.5">
<LinearGradientBrush.GradientStops>
<GradientStop Color="Yellow" Offset="0" />
<GradientStop Color="Red" Offset="0.25" />
<GradientStop Color="Blue" Offset="0.75" />
<GradientStop Color="LimeGreen" Offset="1" />
</LinearGradientBrush.GradientStops>
</LinearGradientBrush>
</DiffuseMaterial.Brush>
</DiffuseMaterial>
</MaterialGroup>
</GeometryModel3D.Material>
<!-- Apply a transform to the object. In this sample, a rotation transform is applied, rendering the
3D object rotated. -->
<GeometryModel3D.Transform>
<RotateTransform3D>
<RotateTransform3D.Rotation>
<AxisAngleRotation3D Axis="0,3,0" Angle="40" />
</RotateTransform3D.Rotation>
</RotateTransform3D>
</GeometryModel3D.Transform>
</GeometryModel3D>
</ModelVisual3D.Content>
</ModelVisual3D>
</Viewport3D.Children>
</Viewport3D>
</Canvas>
</Viewbox>
</DockPanel>
</Page>
下面的代码演示如何以程序代码创建同一三维场景。
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Media3D;
namespace SDKSample
{
public partial class Basic3DShapeExample : Page
{
public Basic3DShapeExample()
{
// Declare scene objects.
Viewport3D myViewport3D = new Viewport3D();
Model3DGroup myModel3DGroup = new Model3DGroup();
GeometryModel3D myGeometryModel = new GeometryModel3D();
ModelVisual3D myModelVisual3D = new ModelVisual3D();
// Defines the camera used to view the 3D object. In order to view the 3D object,
// the camera must be positioned and pointed such that the object is within view
// of the camera.
PerspectiveCamera myPCamera = new PerspectiveCamera();
// Specify where in the 3D scene the camera is.
myPCamera.Position = new Point3D(0, 0, 2);
// Specify the direction that the camera is pointing.
myPCamera.LookDirection = new Vector3D(0, 0, -1);
// Define camera's horizontal field of view in degrees.
myPCamera.FieldOfView = 60;
// Asign the camera to the viewport
myViewport3D.Camera = myPCamera;
// Define the lights cast in the scene. Without light, the 3D object cannot
// be seen. Also, the direction of the lights affect shadowing. Note: to
// illuminate an object from additional directions, create additional lights.
DirectionalLight myDirectionalLight = new DirectionalLight();
myDirectionalLight.Color = Colors.White;
myDirectionalLight.Direction = new Vector3D(-0.61, -0.5, -0.61);
myModel3DGroup.Children.Add(myDirectionalLight);
// The geometry specifes the shape of the 3D plane. In this sample, a flat sheet
// is created.
MeshGeometry3D myMeshGeometry3D = new MeshGeometry3D();
// Create a collection of normal vectors for the MeshGeometry3D.
Vector3DCollection myNormalCollection = new Vector3DCollection();
myNormalCollection.Add(new Vector3D(0,0,1));
myNormalCollection.Add(new Vector3D(0,0,1));
myNormalCollection.Add(new Vector3D(0,0,1));
myNormalCollection.Add(new Vector3D(0,0,1));
myNormalCollection.Add(new Vector3D(0,0,1));
myNormalCollection.Add(new Vector3D(0,0,1));
myMeshGeometry3D.Normals = myNormalCollection;
// Create a collection of vertex positions for the MeshGeometry3D.
Point3DCollection myPositionCollection = new Point3DCollection();
myPositionCollection.Add(new Point3D(-0.5, -0.5, 0.5));
myPositionCollection.Add(new Point3D(0.5, -0.5, 0.5));
myPositionCollection.Add(new Point3D(0.5, 0.5, 0.5));
myPositionCollection.Add(new Point3D(0.5, 0.5, 0.5));
myPositionCollection.Add(new Point3D(-0.5, 0.5, 0.5));
myPositionCollection.Add(new Point3D(-0.5, -0.5, 0.5));
myMeshGeometry3D.Positions = myPositionCollection;
// Create a collection of texture coordinates for the MeshGeometry3D.
PointCollection myTextureCoordinatesCollection = new PointCollection();
myTextureCoordinatesCollection.Add(new Point(0, 0));
myTextureCoordinatesCollection.Add(new Point(1, 0));
myTextureCoordinatesCollection.Add(new Point(1, 1));
myTextureCoordinatesCollection.Add(new Point(1, 1));
myTextureCoordinatesCollection.Add(new Point(0, 1));
myTextureCoordinatesCollection.Add(new Point(0, 0));
myMeshGeometry3D.TextureCoordinates = myTextureCoordinatesCollection;
// Create a collection of triangle indices for the MeshGeometry3D.
Int32Collection myTriangleIndicesCollection = new Int32Collection();
myTriangleIndicesCollection.Add(0);
myTriangleIndicesCollection.Add(1);
myTriangleIndicesCollection.Add(2);
myTriangleIndicesCollection.Add(3);
myTriangleIndicesCollection.Add(4);
myTriangleIndicesCollection.Add(5);
myMeshGeometry3D.TriangleIndices = myTriangleIndicesCollection;
// Apply the mesh to the geometry model.
myGeometryModel.Geometry = myMeshGeometry3D;
// The material specifies the material applied to the 3D object. In this sample a
// linear gradient covers the surface of the 3D object.
// Create a horizontal linear gradient with four stops.
LinearGradientBrush myHorizontalGradient = new LinearGradientBrush();
myHorizontalGradient.StartPoint = new Point(0, 0.5);
myHorizontalGradient.EndPoint = new Point(1, 0.5);
myHorizontalGradient.GradientStops.Add(new GradientStop(Colors.Yellow, 0.0));
myHorizontalGradient.GradientStops.Add(new GradientStop(Colors.Red, 0.25));
myHorizontalGradient.GradientStops.Add(new GradientStop(Colors.Blue, 0.75));
myHorizontalGradient.GradientStops.Add(new GradientStop(Colors.LimeGreen, 1.0));
// Define material and apply to the mesh geometries.
DiffuseMaterial myMaterial = new DiffuseMaterial(myHorizontalGradient);
myGeometryModel.Material = myMaterial;
// Apply a transform to the object. In this sample, a rotation transform is applied,
// rendering the 3D object rotated.
RotateTransform3D myRotateTransform3D = new RotateTransform3D();
AxisAngleRotation3D myAxisAngleRotation3d = new AxisAngleRotation3D();
myAxisAngleRotation3d.Axis = new Vector3D(0,3,0);
myAxisAngleRotation3d.Angle = 40;
myRotateTransform3D.Rotation = myAxisAngleRotation3d;
myGeometryModel.Transform = myRotateTransform3D;
// Add the geometry model to the model group.
myModel3DGroup.Children.Add(myGeometryModel);
// Add the group of models to the ModelVisual3d.
myModelVisual3D.Content = myModel3DGroup;
//
myViewport3D.Children.Add(myModelVisual3D);
// Apply the viewport to the page so it will be rendered.
this.Content = myViewport3D;
}
}
}