DirectX天空球和天空盒子模型

在一些大型的3D游戏中，有几个必不可少的元素，比如说天空和大地，这些元素的存在可以增加3D场景的真实感。三维场景中天空和大地场景的模拟其实很简单，这种场景跟古人所说的“天圆地方”有着异曲同工之妙。天空其实就是一个很大的容器，把整个世界都罩在下面，大地就是一个平面，场景中所有的元素都显示在二者所包围的空间中。三维天空的技术主要包括三种类型：一种是平面型天空（Sky Plane），仅用一个平面盖在所有元素的头顶。这种技术有点弱，很容易被识破，真实感也很低，有时还需要用雾来覆盖远景以增加真实感，但是效果和技术含量依然很低；还有一种就是天空穹庐（Sky
Dome），有时也称为天空球，即放到场景元素头顶上的是一个曲面，通常都会为一个半球，这种技术的真实性和立体感最强，但是不是目前使用最广泛的方案，通常会涉及到天空无缝衔接的素材匮乏等的问题；另外一种就是天空盒子（Sky Box），即把天空做成一个立方体，所有的元素都罩在其下，这种技术是目前使用最广泛的三维天空模拟技术，在一些高级的应用中，天空盒子的纹理可能同时会用来生成Cube Map，并用之来做水面倒影、云影、反光等很眩的特效，网络上关于这方面的素材也很多，感兴趣的可以自己搜一下。这里主要给出后面两种模型的实现即天空球和天空盒子，引擎框架用的是微软的DirectX，用C#来实现。

天空球

因为最近在研究道路的三维仿真，所以实现的背景就是道路的三维显示，为了增加真实感，在其上罩了一个天空球。关于道路的三维显示，采用了一个很简单的思路，利用传感器采集的道路数据，一般是是BMP格式的，把采集获得的BMP数据的输出作为道路的高程图(Height Map)，根据各个点像素值计算道路的高程值(世界坐标系中Y方向上的高度值)，建立顶点缓冲和顶点索引缓冲，再进行三角形构网和道路的纹理贴图就OK了。Demo版本的思路暂时是这样的，这里给出Demo版本的实现。这里贴上一张道路的三维网格效果图如下：



天空球的实现更加简单，利用专业的软件3dsMax把天空模型和大地模型做好，导出.x文件，再利用DirectX提供的接口将其加载进去，然后进行相应的坐标系空间转换调整一下就行了。3dsMax下建好的模型如下：





下面再贴上一张DirectX下实现的带有天空球的道路模型：





这里贴上该模型实现的核心代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Microsoft.DirectX;
using Microsoft.DirectX.Direct3D;
using System.IO;

namespace RoadSkydom
{
public partial class RoadSkydom : Form
{
private Device m_device = null;
bool pause = false;
Mesh skyboxMesh = null;
Material skyboxMeshMaterials;
Texture[] skyboxMeshTextures;
Microsoft.DirectX.Direct3D.Material[] meshMaterials1;
float Angle = 0, ViewZ = -5.0f;

private float angleY = 0.01f;//定义绕Y轴旋转变量

private int mouseLastX, mouseLastY;//记录鼠标按下时的坐标位置
private bool isRotateByMouse = false;//记录是否由鼠标控制旋转
private bool isMoveByMouse = false;//记录是否由鼠标控制移动

private CustomVertex.PositionTextured[] vertices;//定义顶点变量
private Texture texture;//定义贴图变量
private Material material;//定义材质变量

private VertexBuffer vertexBuffer;//定义顶点缓冲变量
private IndexBuffer indexBuffer;//定义索引缓冲变量
private int[] indices;//定义索引号变量

private int xCount = 5, yCount = 4;//定义横向和纵向网格数目
private float cellHeight = 1f, cellWidth = 1f;//定义单元的宽度和长度

Material bottomMaterial;//底部材质变量
Texture bottomTexture;//底部纹理变量
VertexBuffer bottomVertexBuffer = null;//保存建立底部正方形的顶点

private VertexBuffer borderFrontVertexBuffer = null;
private CustomVertex.PositionColored[] borderFrontVertices;//定义前面边缘顶点变量
private IndexBuffer borderFrontIndexBuffer;//定义前面边缘顶点索引缓冲变量
private int[] borderFrontIndices;//定义前面边缘顶点的索引号变量

private VertexBuffer borderBackVertexBuffer = null;
private CustomVertex.PositionColored[] borderBackVertices;//定义背面边缘顶点变量
private IndexBuffer borderBackIndexBuffer;//定义背面边缘顶点索引缓冲变量
private int[] borderBackIndices;//定义背面边缘顶点的索引号变量

private VertexBuffer borderLeftVertexBuffer = null;
private CustomVertex.PositionColored[] borderLeftVertices;//定义左面边缘顶点变量
private IndexBuffer borderLeftIndexBuffer;//定义左面边缘顶点索引缓冲变量
private int[] borderLeftIndices;//定义左面边缘顶点的索引号变量

private VertexBuffer borderRightVertexBuffer = null;
private CustomVertex.PositionColored[] borderRightVertices;//定义右面边缘顶点变量
private IndexBuffer borderRightIndexBuffer;//定义右面边缘顶点索引缓冲变量
private int[] borderRightIndices;//定义右面边缘顶点的索引号变量
public RoadSkydom()
{
InitializeComponent();
}
public bool InitializeGraphics()
{
try
{
PresentParameters presentParams = new PresentParameters();
presentParams.Windowed = true;				//不是全屏显示，在一个窗口显示
presentParams.SwapEffect = SwapEffect.Discard;		 //后备缓存交换的方式
presentParams.EnableAutoDepthStencil = true;			 //允许使用自动深度模板测试
//深度缓冲区单元为16位二进制数
presentParams.AutoDepthStencilFormat = DepthFormat.D16;
m_device = new Device(0, DeviceType.Hardware, this, 	 //建立设备类对象
CreateFlags.SoftwareVertexProcessing, presentParams);
//设置设备重置事件(device.DeviceReset)事件函数为this.OnResetDevice
m_device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(m_device, null);//自定义方法，初始化Device的工作放到这个方法中
this.OnResetDevice(m_device, null);//调用设备重置事件(device.DeviceReset)事件函数
}		//设备重置事件函数要设置Device参数，初始函数中必须调用该函数
catch (DirectXException)
{
return false;
}
return true;
}

public void OnCreateDevice(object sender, EventArgs e)
{
Device device = (Device)sender;
ExtendedMaterial[] materials = null;
//设定运行程序所在目录的上两级目录为当前默认目录
Directory.SetCurrentDirectory(Application.StartupPath + @"\..\..\..\");
GraphicsStream adjacency;

skyboxMesh = Mesh.FromFile("skydom_bottom.x", MeshFlags.Managed, m_device, out adjacency, out materials);
if (skyboxMeshTextures == null)			//如果还未设置纹理，为3D图形增加纹理和材质
{
skyboxMeshTextures = new Texture[materials.Length];				//纹理数组
meshMaterials1 = new Material[materials.Length];			//材质数组
for (int i = 0; i < materials.Length; i++)					//读入纹理和材质
{
meshMaterials1[i] = materials[i].Material3D;
meshMaterials1[i].Ambient = meshMaterials1[i].Diffuse;
skyboxMeshTextures[i] = TextureLoader.FromFile(m_device,
materials[i].TextureFilename);
}
}	//下句优化Mesh，减少属性的状态改变提高渲染速度
skyboxMesh.Optimize(MeshFlags.Managed | MeshFlags.OptimizeAttributeSort, adjacency);

material = new Material();
material.Diffuse = Color.White;
material.Specular = Color.LightGray;
material.SpecularSharpness = 15.0F;
device.Material = material;
texture = TextureLoader.FromFile(device, @"F:\\workdir\\VC# Based DirectX\\RoadTexture.jpg");

//底部材料和贴图
bottomMaterial = new Material();
bottomMaterial.Ambient = Color.FromArgb(200, 255, 255, 255);
bottomMaterial.Diffuse = Color.FromArgb(200, 255, 255, 255);
bottomTexture = TextureLoader.FromFile(device, "F:\\workdir\\VC# Based DirectX\\BottomTexture.bmp");
bottomVertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionNormalTextured), 6, device, 0, CustomVertex.PositionNormalTextured.Format, Pool.Default);
bottomVertexBuffer.Created += new System.EventHandler(this.OnCreateBottomVertexBuffer);
this.OnCreateBottomVertexBuffer(device, null);
}
//底部顶点
public void OnCreateBottomVertexBuffer(object sender, EventArgs e)
{
CustomVertex.PositionNormalTextured[] bottomVerts = (CustomVertex.PositionNormalTextured[])bottomVertexBuffer.Lock(0, 0);//绘制底面正方形的6个顶点
string bitmapPath = @"F:\\workdir\\VC# Based DirectX\\RoadHeight.BMP";
float minHeight = GetMinHeight(bitmapPath);
float xWidth = GetBitMapWidth(bitmapPath);
float yHeight = GetBitMapHeight(bitmapPath);
bottomVerts[0].Position = new Vector3(-100.0f, minHeight - 5.0f, -100.0f);
bottomVerts[0].Normal = new Vector3(0, 0, -1);
bottomVerts[0].Tu = 0.0f;//顶点0纹理坐标Tu
bottomVerts[0].Tv = 5.0f;//纹理图片沿Y轴方向重复贴图50次

bottomVerts[1].Position = new Vector3(-100.0f, minHeight - 5.0f, yHeight + 100.0f);
bottomVerts[1].Normal = new Vector3(0, 0, -1);
bottomVerts[1].Tu = 0.0f;
bottomVerts[1].Tv = 0.0f;

bottomVerts[2].Position = new Vector3(xWidth + 100.0f, minHeight - 5.0f, yHeight + 100.0f);
bottomVerts[2].Normal = new Vector3(0, 0, -1);
bottomVerts[2].Tu = 5.0f;
bottomVerts[2].Tv = 0.0f;

bottomVerts[3].Position = new Vector3(-100.0f, minHeight - 5.0f, -100.0f);
bottomVerts[3].Normal = new Vector3(0, 0, -1);
bottomVerts[3].Tu = 0.0f;
bottomVerts[3].Tv = 5.0f;

bottomVerts[4].Position = new Vector3(xWidth + 100.0f, minHeight - 5.0f, yHeight + 100.0f);
bottomVerts[4].Normal = new Vector3(0, 0, -1);
bottomVerts[4].Tu = 5.0f;
bottomVerts[4].Tv = 0.0f;

bottomVerts[5].Position = new Vector3(xWidth + 100.0f, minHeight - 5.0f, -100.0f);
bottomVerts[5].Normal = new Vector3(0, 0, -1);
bottomVerts[5].Tu = 5.0f;
bottomVerts[5].Tv = 5.0f;

bottomVertexBuffer.Unlock();
}
//避免精度损失
public float GetBitMapHeight(string bitmapPath)
{
Bitmap bitmap = new Bitmap(bitmapPath);
xCount = (bitmap.Width - 1) / 2;
yCount = xCount;
cellWidth = bitmap.Width / xCount;
cellHeight = bitmap.Height / yCount;
return (float)(yCount * cellHeight);
}
//避免精度损失
public float GetBitMapWidth(string bitmapPath)
{
Bitmap bitmap = new Bitmap(bitmapPath);
xCount = (bitmap.Width - 1) / 2;
yCount = xCount;
cellWidth = bitmap.Width / xCount;
cellHeight = bitmap.Height / yCount;
return (float)(xCount * cellWidth);
}
//获得高度图Y方向上的最小高度值
public float GetMinHeight(string bitmapPath)
{
float minHeight = 6553500.0f;
Bitmap bitmap = new Bitmap(bitmapPath);
xCount = (bitmap.Width - 1) / 2;
yCount = xCount;
cellWidth = bitmap.Width / xCount;
cellHeight = bitmap.Height / yCount;
for (int i = 0; i < yCount + 1; i++)
for (int j = 0; j < xCount + 1; j++)
{
Color color = bitmap.GetPixel((int)(j * cellWidth), (int)(i * cellHeight));
float height = float.Parse(color.R.ToString()) +
float.Parse(color.G.ToString()) + float.Parse(color.B.ToString());
height /= 10;
if (height < minHeight)
minHeight = height;
}
return minHeight;
}

public void OnResetDevice(object sender, EventArgs e)
{
Device device = (Device)sender;
device.RenderState.ZBufferEnable = true;		 	//允许使用深度缓冲
device.RenderState.Ambient = System.Drawing.Color.White;//设定环境光为白色
device.Lights[0].Type = LightType.Directional;  	//设置灯光类型
device.Lights[0].Diffuse = Color.White;			//设置灯光颜色
device.Lights[0].Direction = new Vector3(0, -1, 0);	//设置灯光位置
device.Lights[0].Update();						//更新灯光设置，创建第一盏灯光
device.Lights[0].Enabled = true;				//使设置有效

string bitmapPath = @"F:\\workdir\\VC# Based DirectX\\RoadHeight.BMP";
Bitmap bitmap = new Bitmap(bitmapPath);
xCount = (bitmap.Width - 1) / 2;
yCount = xCount;
cellWidth = bitmap.Width / xCount;
cellHeight = bitmap.Height / yCount;

vertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionTextured), (xCount + 1) * (yCount + 1), device,
Usage.Dynamic | Usage.WriteOnly, CustomVertex.PositionColored.Format, Pool.Default);
vertices = new CustomVertex.PositionTextured[(xCount + 1) * (yCount + 1)];//定义顶点
for (int i = 0; i < yCount + 1; i++)
{
for (int j = 0; j < xCount + 1; j++)
{
Color color = bitmap.GetPixel((int)(j * cellWidth), (int)(i * cellHeight));
float height = float.Parse(color.R.ToString()) + float.Parse(color.G.ToString()) + float.Parse(color.B.ToString());
height /= 10;
vertices[j + i * (xCount + 1)].Position = new Vector3(j * cellWidth, height, i * cellHeight);
vertices[j + i * (xCount + 1)].Tu = (float)j / (xCount + 1);
vertices[j + i * (xCount + 1)].Tv = (float)i / (yCount + 1);
}
}
vertexBuffer.SetData(vertices, 0, LockFlags.None);
CamTarget = new Vector3(bitmap.Width / 2, 0f, bitmap.Height / 2);//设置摄像机目标位置

indexBuffer = new IndexBuffer(typeof(int), 6 * xCount * yCount, device, Usage.WriteOnly, Pool.Default);
indices = new int[6 * xCount * yCount];
for (int i = 0; i < yCount; i++)
{
for (int j = 0; j < xCount; j++)
{
indices[6 * (j + i * xCount)] = j + i * (xCount + 1);
indices[6 * (j + i * xCount) + 1] = j + (i + 1) * (xCount + 1);
indices[6 * (j + i * xCount) + 2] = j + i * (xCount + 1) + 1;
indices[6 * (j + i * xCount) + 3] = j + i * (xCount + 1) + 1;
indices[6 * (j + i * xCount) + 4] = j + (i + 1) * (xCount + 1);
indices[6 * (j + i * xCount) + 5] = j + (i + 1) * (xCount + 1) + 1;
}
}
indexBuffer.SetData(indices, 0, LockFlags.None);
/*******第1个四周边界********/
float minY = GetMinHeight(bitmapPath) - 5.0f;
borderFrontVertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionColored),
2 * (xCount + 1),//四周的一个面封闭总共所需要的顶点的数目
device,
Usage.Dynamic | Usage.WriteOnly,
CustomVertex.PositionColored.Format,
Pool.Default);
borderFrontVertices = new CustomVertex.PositionColored[2 * (xCount + 1)];//定义顶点
int k;
for (k = 0; k < xCount + 1; k++)//X轴上的点的定义
{
borderFrontVertices[k].Position = new Vector3(k * cellWidth, minY, 0.0f);
borderFrontVertices[k].Color = System.Drawing.Color.Red.ToArgb();
}
for (; k < 2 * (xCount + 1); k++)//高程图上的边界点的定义
{
Color color = bitmap.GetPixel((int)((k - xCount - 1) * cellWidth), 0);
float height = float.Parse(color.R.ToString()) + float.Parse(color.G.ToString()) + float.Parse(color.B.ToString());
height /= 10;
borderFrontVertices[k].Position = new Vector3((k - xCount - 1) * cellWidth, height, 0);//i * cellHeight=0
borderFrontVertices[k].Color = System.Drawing.Color.Aqua.ToArgb();
}

borderFrontVertexBuffer.SetData(borderFrontVertices, 0, LockFlags.None);

borderFrontIndexBuffer = new IndexBuffer(typeof(int),
6 * xCount * 1,
device,
Usage.WriteOnly,
Pool.Default);
borderFrontIndices = new int[6 * xCount * 1];//初始化索引顶点

for (int j = 0; j < xCount; j++)
{
borderFrontIndices[6 * (j)] = j;
borderFrontIndices[6 * (j) + 1] = j + (xCount + 1);
borderFrontIndices[6 * (j) + 2] = j + 1;
borderFrontIndices[6 * (j) + 3] = j + 1;
borderFrontIndices[6 * (j) + 4] = j + (xCount + 1);
borderFrontIndices[6 * (j) + 5] = j + (xCount + 1) + 1;
}
borderFrontIndexBuffer.SetData(borderFrontIndices, 0, LockFlags.None);

/**第2个四周边界**/
borderBackVertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionColored),
2 * (xCount + 1),//四周的一个面封闭总共所需要的顶点的数目
device,
Usage.Dynamic | Usage.WriteOnly,
CustomVertex.PositionColored.Format,
Pool.Default);
borderBackVertices = new CustomVertex.PositionColored[2 * (xCount + 1)];//定义顶点
for (k = 0; k < xCount + 1; k++)//X轴平行方向上的点的定义
{
borderBackVertices[k].Position = new Vector3(k * cellWidth, minY, yCount * cellHeight);
borderBackVertices[k].Color = System.Drawing.Color.Aqua.ToArgb();
}
for (; k < 2 * (xCount + 1); k++)//高程图上的边界点的定义
{
Color color = bitmap.GetPixel((int)((k - xCount - 1) * cellWidth), (int)(yCount * cellHeight));//不能直接写死
float height = float.Parse(color.R.ToString()) + float.Parse(color.G.ToString()) + float.Parse(color.B.ToString());
height /= 10;
borderBackVertices[k].Position = new Vector3((k - xCount - 1) * cellWidth, height, yCount * cellHeight);
borderBackVertices[k].Color = System.Drawing.Color.Aqua.ToArgb();
}

borderBackVertexBuffer.SetData(borderBackVertices, 0, LockFlags.None);

borderBackIndexBuffer = new IndexBuffer(typeof(int),
6 * xCount * 1,
device,
Usage.WriteOnly,
Pool.Default);
borderBackIndices = new int[6 * xCount * 1];//初始化索引顶点

for (int j = 0; j < xCount; j++)
{
borderBackIndices[6 * (j)] = j;
borderBackIndices[6 * (j) + 1] = j + (xCount + 1);
borderBackIndices[6 * (j) + 2] = j + 1;
borderBackIndices[6 * (j) + 3] = j + 1;
borderBackIndices[6 * (j) + 4] = j + (xCount + 1);
borderBackIndices[6 * (j) + 5] = j + (xCount + 1) + 1;
}
borderBackIndexBuffer.SetData(borderBackIndices, 0, LockFlags.None);

int diff = yCount - xCount;
/**第3个四周边界**/
borderLeftVertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionColored),
2 * (yCount + 1),//四周的一个面封闭总共所需要的顶点的数目
device,
Usage.Dynamic | Usage.WriteOnly,
CustomVertex.PositionColored.Format,
Pool.Default);
borderLeftVertices = new CustomVertex.PositionColored[2 * (yCount + 1)];//定义顶点

for (k = 0; k < yCount + 1; k++)//Z轴平行方向上的点的定义
{
borderLeftVertices[k].Position = new Vector3(0, minY, k * cellHeight);
borderLeftVertices[k].Color = System.Drawing.Color.Aqua.ToArgb();
}
for (; k < 2 * (yCount + 1); k++)//高程图上的边界点的定义
{
Color color = bitmap.GetPixel(0, (int)((k - yCount - 1) * cellHeight));//边界点不能直接传进去写死，容易产生溢出的异常
float height = float.Parse(color.R.ToString()) + float.Parse(color.G.ToString()) + float.Parse(color.B.ToString());
height /= 10;
borderLeftVertices[k].Position = new Vector3(0, height, (k - yCount - 1) * cellHeight);
borderLeftVertices[k].Color = System.Drawing.Color.Aqua.ToArgb();
}

borderLeftVertexBuffer.SetData(borderLeftVertices, 0, LockFlags.None);

borderLeftIndexBuffer = new IndexBuffer(typeof(int),
6 * yCount * 1,
device,
Usage.WriteOnly,
Pool.Default);
borderLeftIndices = new int[6 * yCount * 1];//初始化索引顶点

for (int j = 0; j < yCount; j++)
{
borderLeftIndices[6 * (j)] = j;
borderLeftIndices[6 * (j) + 1] = j + (yCount + 1);
borderLeftIndices[6 * (j) + 2] = j + 1;
borderLeftIndices[6 * (j) + 3] = j + 1;
borderLeftIndices[6 * (j) + 4] = j + (yCount + 1);
borderLeftIndices[6 * (j) + 5] = j + (yCount + 1) + 1;
}
borderLeftIndexBuffer.SetData(borderLeftIndices, 0, LockFlags.None);
//MessageBox.Show(borderLeftIndices[0]+","+borderLeftIndices[1]+","+borderLeftIndices[2]);

/**第4个四周边界**/
borderRightVertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionColored),
2 * (yCount + 1),//四周的一个面封闭总共所需要的顶点的数目
device,
Usage.Dynamic | Usage.WriteOnly,
CustomVertex.PositionColored.Format,
Pool.Default);
borderRightVertices = new CustomVertex.PositionColored[2 * (yCount + 1)];//定义顶点
for (k = 0; k < yCount + 1; k++)//Z轴平行方向上的点的定义
{
borderRightVertices[k].Position = new Vector3(xCount * cellWidth, minY, k * cellHeight);
borderRightVertices[k].Color = System.Drawing.Color.Aqua.ToArgb();
}
for (; k < 2 * (yCount + 1); k++)//高程图上的边界点的定义
{
Color color = bitmap.GetPixel((int)(xCount * cellWidth), (int)((k - yCount - 1) * cellHeight));//边界点不能直接传进去写死，容易产生溢出和精度损失
float height = float.Parse(color.R.ToString()) + float.Parse(color.G.ToString()) + float.Parse(color.B.ToString());
height /= 10;
borderRightVertices[k].Position = new Vector3(xCount * cellWidth, height, (k - yCount - 1) * cellHeight);
borderRightVertices[k].Color = System.Drawing.Color.Aqua.ToArgb();
}

borderRightVertexBuffer.SetData(borderRightVertices, 0, LockFlags.None);

borderRightIndexBuffer = new IndexBuffer(typeof(int),
6 * yCount * 1,
device,
Usage.WriteOnly,
Pool.Default);
borderRightIndices = new int[6 * yCount * 1];//初始化索引顶点

for (int j = 0; j < yCount; j++)
{
borderRightIndices[6 * (j)] = j;
borderRightIndices[6 * (j) + 1] = j + (yCount + 1);
borderRightIndices[6 * (j) + 2] = j + 1;
borderRightIndices[6 * (j) + 3] = j + 1;
borderRightIndices[6 * (j) + 4] = j + (yCount + 1);
borderRightIndices[6 * (j) + 5] = j + (yCount + 1) + 1;
}
borderRightIndexBuffer.SetData(borderRightIndices, 0, LockFlags.None);

device.SamplerState[0].MagFilter = TextureFilter.Linear;//使用纹理滤波器进行线性滤波

}
private Vector3 CamPostion = new Vector3(0.0f, 0.0f, -100.0f);//定义摄像机位置
private Vector3 CamTarget = new Vector3(0.0f, 0.0f, 0.0f);//定义摄像机目标位置
//         void SetupMatrices()
//         {
//             m_device.Transform.World = Matrix.RotationX((float)Math.PI/180)*Matrix.Translation(0,-20,0);//世界变换，下调为观察变换矩阵
//             Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
//             m_device.Transform.Projection = Matrix.PerspectiveFovLH((float)Math.PI / 4, this.Width / this.Height, 1.0f, 6500.0f);
//             m_device.Transform.View = viewMatrix;
//         }
public void Render()
{
if (m_device == null)
return;
m_device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.White, 1.0f, 0);
/*SetupMatrices();*/
m_device.Transform.World = Matrix.Scaling(8,8,8)*Matrix.Translation(250,0,250);//世界变换，下调为观察变换矩阵
m_device.Transform.View = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.Projection = Matrix.PerspectiveFovLH((float)Math.PI / 4, this.Width / this.Height, 1.0f, 6500.0f);

m_device.BeginScene();
m_device.RenderState.FillMode = FillMode.Solid;
m_device.RenderState.CullMode = Cull.None;
m_device.RenderState.Lighting = false;

m_device.Material = skyboxMeshMaterials;					//指定设备的材质
for (int i = 0; i < meshMaterials1.Length; i++)		//Mesh中可能有多个3D图形，逐一显示
{
m_device.Material = meshMaterials1[i];		//设定3D图形的材质
m_device.SetTexture(0, skyboxMeshTextures[i]);	//设定3D图形的纹理
skyboxMesh.DrawSubset(i);
}
m_device.Transform.World = Matrix.Identity;

Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.Projection = Matrix.PerspectiveFovLH(
(float)Math.PI / 4,
this.Width / this.Height,
1.0f,
6500.0f);
m_device.Transform.View = viewMatrix;

m_device.SetTexture(0, texture);//设置贴图
m_device.VertexFormat = CustomVertex.PositionTextured.Format;
m_device.SetStreamSource(0, vertexBuffer, 0);
m_device.Indices = indexBuffer;
m_device.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0, (xCount + 1) * (yCount + 1), 0, indices.Length / 3);

//m_device.Transform.World = Matrix.Translation(0.0f, 0.0f, 0.0f);//底部世界变换
//             m_device.Material = bottomMaterial;//底部使用的材质
//
//             m_device.RenderState.DiffuseMaterialSource = ColorSource.Material;
//             m_device.RenderState.AlphaBlendEnable = true;
//             m_device.SetTexture(0, bottomTexture);
//
//             m_device.SetStreamSource(0, bottomVertexBuffer, 0);
//             m_device.VertexFormat = CustomVertex.PositionNormalTextured.Format;
//             m_device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);

/*第1个边界三角形*/
m_device.SetStreamSource(0, borderFrontVertexBuffer, 0);
m_device.VertexFormat = CustomVertex.PositionColored.Format;
m_device.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0, 2 * (xCount + 1), 0, borderFrontIndices.Length / 3);
/*第2个边界三角形*/
m_device.SetStreamSource(0, borderBackVertexBuffer, 0);
m_device.VertexFormat = CustomVertex.PositionColored.Format;
m_device.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0, 2 * (xCount + 1), 0, borderBackIndices.Length / 3);
/*第3个边界三角形*/
m_device.SetStreamSource(0, borderLeftVertexBuffer, 0);
m_device.VertexFormat = CustomVertex.PositionColored.Format;
m_device.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0, 2 * (yCount + 1), 0, borderLeftIndices.Length / 3);
/*第4个边界三角形*/
m_device.SetStreamSource(0, borderRightVertexBuffer, 0);
m_device.VertexFormat = CustomVertex.PositionColored.Format;
m_device.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0, 2 * (yCount + 1), 0, borderRightIndices.Length / 3);

m_device.EndScene();
m_device.Present();
}
private void OnKeyDown(object sender, KeyEventArgs e)
{
Vector4 tempV4;
Matrix currentView = m_device.Transform.View;//当前摄像机的视图矩阵
switch (e.KeyCode)
{
case Keys.Left:
CamPostion.Subtract(CamTarget);
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(currentView.M12, currentView.M22, currentView.M32), -angleY)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
break;
case Keys.Right:
CamPostion.Subtract(CamTarget);
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(currentView.M12, currentView.M22, currentView.M32), angleY)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
break;
case Keys.Up:
CamPostion.Subtract(CamTarget);
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(m_device.Transform.View.M11
, m_device.Transform.View.M21, m_device.Transform.View.M31), -angleY)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
break;
case Keys.Down:
CamPostion.Subtract(CamTarget);
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(m_device.Transform.View.M11
, m_device.Transform.View.M21, m_device.Transform.View.M31), angleY)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
break;
case Keys.Add:
CamPostion.Subtract(CamTarget);
CamPostion.Scale(0.95f);
CamPostion.Add(CamTarget);
break;
case Keys.Subtract:
CamPostion.Subtract(CamTarget);
CamPostion.Scale(1.05f);
CamPostion.Add(CamTarget);
break;
}
Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.View = viewMatrix;
Render();
}

private void OnMouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
mouseLastX = e.X;
mouseLastY = e.Y;
isRotateByMouse = true;
}
else if (e.Button == MouseButtons.Middle)
{
mouseLastX = e.X;
mouseLastY = e.Y;
isMoveByMouse = true;
}
}

private void OnMouseUp(object sender, MouseEventArgs e)
{
isRotateByMouse = false;
isMoveByMouse = false;
}

private void OnMouseMove(object sender, MouseEventArgs e)
{
if (isRotateByMouse)
{
Matrix currentView = m_device.Transform.View;//当前摄像机的视图矩阵
float tempAngleY = 2 * (float)(e.X - mouseLastX) / this.Width;
CamPostion.Subtract(CamTarget);

Vector4 tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(currentView.M12, currentView.M22, currentView.M32), tempAngleY)));
CamPostion.X = tempV4.X;
CamPostion.Y = tempV4.Y;
CamPostion.Z = tempV4.Z;

float tempAngleX = 4 * (float)(e.Y - mouseLastY) / this.Height;
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(currentView.M11, currentView.M21, currentView.M31), tempAngleX)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.View = viewMatrix;

mouseLastX = e.X;
mouseLastY = e.Y;
Render();
}
else if (isMoveByMouse)
{
Matrix currentView = m_device.Transform.View;//当前摄像机的视图矩阵
float moveFactor = 0.01f;
CamTarget.X += -moveFactor * ((e.X - mouseLastX) * currentView.M11 - (e.Y - mouseLastY) * currentView.M12);
CamTarget.Y += -moveFactor * ((e.X - mouseLastX) * currentView.M21 - (e.Y - mouseLastY) * currentView.M22);
CamTarget.Z += -moveFactor * ((e.X - mouseLastX) * currentView.M31 - (e.Y - mouseLastY) * currentView.M32);

CamPostion.X += -moveFactor * ((e.X - mouseLastX) * currentView.M11 - (e.Y - mouseLastY) * currentView.M12);
CamPostion.Y += -moveFactor * ((e.X - mouseLastX) * currentView.M21 - (e.Y - mouseLastY) * currentView.M22);
CamPostion.Z += -moveFactor * ((e.X - mouseLastX) * currentView.M31 - (e.Y - mouseLastY) * currentView.M32);

Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.View = viewMatrix;
mouseLastX = e.X;
mouseLastY = e.Y;
Render();
}
}
private void OnMouseWheel(object sender, MouseEventArgs e)
{
float scaleFactor = -(float)e.Delta / 2000 + 1f;
CamPostion.Subtract(CamTarget);
CamPostion.Scale(scaleFactor);
CamPostion.Add(CamTarget);
Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.View = viewMatrix;
Render();
}

private void OnLoad(object sender, EventArgs e)
{
InitializeGraphics();
this.Show();
Render();
}
private void OnPaint(object sender, PaintEventArgs e)
{
this.Render();
}

private void OnResize(object sender, EventArgs e)
{
pause = ((this.WindowState == FormWindowState.Minimized) || !this.Visible);
}
}
}

天空盒子

天空盒子的实现更加简单，这个可以完全通过代码来实现，需要准备几张天空360°无缝衔接的全景图，然后按照一定的顺组组合贴图即可。



建立一个立方体模型，为了增加渲染的效率，可以考虑只绘制一个基准面，然后利用这个基准面进行旋转平移变换就可以得到其他的面，绘制的时候，设置不同的纹理贴图即可。下面贴上几张天空盒子的效果图：







下面附上实现的核心代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Microsoft.DirectX;
using Microsoft.DirectX.Direct3D;

namespace Test
{
public partial class SkyBox : Form
{
private Device m_device = null;
bool pause = false;
VertexBuffer skyboxVertexBuffer = null;
Material skyboxMtrl;
float Angle = 0, ViewZ = -6.0f;
Texture skyboxFrontTexture = null;//定义skybox模型6个面的纹理变量
Texture skyboxBackTexture = null;
Texture skyboxTopTexture = null;
Texture skyboxBottomTexture = null;
Texture skyboxLeftTexture = null;
Texture skyboxRightTexture = null;

private float angleY = 0.0f;//定义绕Y轴旋转变量

private int mouseLastX, mouseLastY;//记录鼠标按下时的坐标位置
private bool isRotateByMouse = false;//记录是否由鼠标控制旋转
private bool isMoveByMouse = false;//记录是否由鼠标控制移动

public SkyBox()
{
InitializeComponent();
}

public bool InitializeGraphics()
{
try
{
PresentParameters presentParams = new PresentParameters();
presentParams.Windowed = true;				//不是全屏显示，在一个窗口显示
presentParams.SwapEffect = SwapEffect.Discard;		 //后备缓存交换的方式
presentParams.EnableAutoDepthStencil = true;			 //允许使用自动深度模板测试
//深度缓冲区单元为16位二进制数
presentParams.AutoDepthStencilFormat = DepthFormat.D16;
m_device = new Device(0, DeviceType.Hardware, this, CreateFlags.SoftwareVertexProcessing, presentParams);
//设置设备重置事件(device.DeviceReset)事件函数为this.OnResetDevice
m_device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(m_device, null);//自定义方法，初始化Device的工作放到这个方法中
this.OnResetDevice(m_device, null);//调用设备重置事件(device.DeviceReset)事件函数
}		//设备重置事件函数要设置Device参数，初始函数中必须调用该函数
catch (DirectXException)
{
return false;
}
return true;
}

public void OnCreateDevice(object sender, EventArgs e)
{
Device dev = (Device)sender;
skyboxVertexBuffer = new VertexBuffer(
typeof(CustomVertex.PositionNormalTextured),
6,
dev,
0,
CustomVertex.PositionNormalTextured.Format,
Pool.Default);
skyboxVertexBuffer.Created += new System.EventHandler(this.OnCreateSkyBoxVertexBuffer);
this.OnCreateSkyBoxVertexBuffer(skyboxVertexBuffer, null);

skyboxMtrl = new Material();
skyboxMtrl.Diffuse = System.Drawing.Color.Yellow;		//物体的颜色
skyboxMtrl.Ambient = System.Drawing.Color.Red;			//反射环境光的颜色
skyboxFrontTexture = TextureLoader.FromFile(dev, @"F:\\workdir\\VC# Based DirectX\\skybox\\neg_z.bmp");
skyboxBackTexture = TextureLoader.FromFile(dev, @"F:\\workdir\\VC# Based DirectX\\skybox\\pos_z.bmp");
skyboxTopTexture = TextureLoader.FromFile(dev, @"F:\\workdir\\VC# Based DirectX\\skybox\\pos_y.bmp");
skyboxBottomTexture = TextureLoader.FromFile(dev, @"F:\\workdir\\VC# Based DirectX\\skybox\\neg_y.bmp");
skyboxLeftTexture = TextureLoader.FromFile(dev, @"F:\\workdir\\VC# Based DirectX\\skybox\\pos_x.bmp");
skyboxRightTexture = TextureLoader.FromFile(dev, @"F:\\workdir\\VC# Based DirectX\\skybox\\neg_x.bmp");
}
public void OnCreateSkyBoxVertexBuffer(object sender, EventArgs e)
{
CustomVertex.PositionNormalTextured[] verts =
(CustomVertex.PositionNormalTextured[])skyboxVertexBuffer.Lock(0, 0);
verts[0].Position = new Vector3(-10.0f, -10.0f, 0.0f);	  //顶点0位置
verts[0].Normal = new Vector3(0, 0, -1);    	  		  //顶点0法线
verts[0].Tu = 0.0f;    	  						  	  //顶点0纹理坐标Tu
verts[0].Tv = 1.0f;
verts[1].Position = new Vector3(-10.0f, 10.0f, 0.0f);	  	  //顶点1位置
verts[1].Normal = new Vector3(0, 0, -1);				  //顶点1法线
verts[1].Tu = 0.0f;    	  							  //顶点0纹理坐标Tu
verts[1].Tv = 0.0f;
verts[2].Position = new Vector3(10.0f, 10.0f, 0.0f);	      //顶点2位置
verts[2].Normal = new Vector3(0, 0, -1);
verts[2].Tu = 1.0f;    	  							  //顶点0纹理坐标Tu
verts[2].Tv = 0.0f;
verts[3].Position = new Vector3(-10.0f, -10.0f, 0.0f);	  //顶点3位置
verts[3].Normal = new Vector3(0, 0, -1);    	  		  //顶点3法线
verts[3].Tu = 0.0f;    	  							  //顶点0纹理坐标Tu
verts[3].Tv = 1.0f;
verts[4].Position = new Vector3(10.0f, 10.0f, 0.0f);	  	  //顶点4位置
verts[4].Normal = new Vector3(0, 0, -1);
verts[4].Tu = 1.0f;    	  							  //顶点0纹理坐标Tu
verts[4].Tv = 0.0f;
verts[5].Position = new Vector3(10.0f, -10.0f, 0.0f);	      //顶点5位置
verts[5].Normal = new Vector3(0, 0, -1);
verts[5].Tu = 1.0f;    	  							  //顶点0纹理坐标Tu
verts[5].Tv = 1.0f;
skyboxVertexBuffer.Unlock();
}

public void OnResetDevice(object sender, EventArgs e)
{
Device dev = (Device)sender;
dev.RenderState.CullMode = Cull.None;		//没有背面剔除
m_device.RenderState.ZBufferEnable = true;				//打开Z缓冲
m_device.RenderState.Lighting = false;					//打开灯光
//SetupLights();										//设置灯光
//m_device.SamplerState[0].MagFilter = TextureFilter.Linear;//使用线性滤波，结合处容易出现裂缝
}

public void Render()		//渲染方法，本方法没有任何渲染代码，可认为是渲染方法的框架
{
if (m_device == null) //如果未建立设备对象，退出
return;
if (pause)
return;
m_device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.WhiteSmoke, 1.0f, 0);
m_device.BeginScene();		//开始渲染

SetupMatrices();
m_device.RenderState.CullMode = Cull.None;
m_device.RenderState.FillMode = FillMode.Solid;

m_device.SetStreamSource(0, skyboxVertexBuffer, 0);
m_device.VertexFormat = CustomVertex.PositionNormalTextured.Format;

m_device.SetTexture(0, skyboxFrontTexture);
m_device.Transform.World =
Matrix.Translation(0, 0, -10);//沿Z轴向观察者方向移动10个单位
m_device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);//正前面

m_device.SetTexture(0, skyboxBackTexture);
m_device.Transform.World =
Matrix.RotationY((float)Math.PI) * Matrix.Translation(0, 0, 10);
m_device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);//正后面

m_device.SetTexture(0, skyboxRightTexture);
m_device.Transform.World =
Matrix.RotationY(-(float)Math.PI / 2) * Matrix.Translation(10, 0, 0);
m_device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);//右侧面

m_device.SetTexture(0, skyboxLeftTexture);
m_device.Transform.World =
Matrix.RotationY((float)Math.PI / 2) * Matrix.Translation(-10, 0, 0);
m_device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);//左侧面

m_device.SetTexture(0, skyboxTopTexture);
m_device.Transform.World =
Matrix.RotationX((float)Math.PI / 2) * Matrix.RotationY(-(float)Math.PI / 2) * Matrix.Translation(0, 10, 0);
m_device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);//上面

m_device.SetTexture(0, skyboxBottomTexture);
m_device.Transform.World =
Matrix.RotationX(-(float)Math.PI / 2) * Matrix.RotationY(-(float)Math.PI/2)*Matrix.Translation(0, -10, 0);
m_device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);//下面

m_device.EndScene();			//渲染结束
m_device.Present();	//更新显示区域，把后备缓存的D图形送到图形卡的显存中显示

}
private Vector3 CamPostion = new Vector3(0.0f, 0.0f, -5.0f);//定义摄像机位置
private Vector3 CamTarget = new Vector3(0.0f, 0.0f, 0.0f);//定义摄像机目标位置
private void SetupMatrices()		//注意世界变换和观察变换参数可能要改变
{
//             device.Transform.World = Matrix.RotationY(0);	//世界变换矩阵
//             Vector3 v1 = new Vector3(0.0f, 0.0f, -5.0f);		//下句使v1点分别沿Y轴和X轴旋转
//             v1.TransformCoordinate(Matrix.RotationYawPitchRoll(Angle, ViewZ, 0));
//             device.Transform.View = Matrix.LookAtLH(v1, new Vector3(0.0f, 0.0f, 0.0f), new Vector3(0.0f, 1.0f, 0.0f));	//观察变换矩阵
//             device.Transform.Projection = Matrix.PerspectiveFovLH((float)Math.PI / 4,
//                             this.Width/this.Height, 1.0f, 100.0f);			//投影变换矩阵
Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.Projection = Matrix.PerspectiveFovLH(
(float)Math.PI / 4,
this.Width / this.Height,
1.0f,
6500.0f);
m_device.Transform.View = viewMatrix;
}

private void SetupLights()
{
m_device.Material = skyboxMtrl;
m_device.Lights[0].Type = LightType.Directional;			//灯光类型
m_device.Lights[0].Diffuse = System.Drawing.Color.White;	//光的颜色为白色
m_device.Lights[0].Direction = new Vector3(0, -2, 4);//灯光方向从观察者上方指向屏幕下方
m_device.Lights[0].Update();			//更新灯光设置，创建第一盏灯光
m_device.Lights[0].Enabled = true;		//使设置有效，下句设置环境光为白色
m_device.RenderState.Ambient = System.Drawing.Color.FromArgb(0x808080);
}

private void Form1_Load(object sender, EventArgs e)
{
InitializeGraphics();
this.Show();
Render();
}
private void Form1_Paint(object sender, PaintEventArgs e)
{
this.Render();
}

private void Form1_Resize(object sender, EventArgs e)
{
pause = ((this.WindowState == FormWindowState.Minimized) || !this.Visible);
}

private void OnKeyDown(object sender, KeyEventArgs e)
{
Vector4 tempV4;
Matrix currentView = m_device.Transform.View;//当前摄像机的视图矩阵
switch (e.KeyCode)
{
case Keys.Left:
CamPostion.Subtract(CamTarget);
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(currentView.M12, currentView.M22, currentView.M32), -angleY)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
break;
case Keys.Right:
CamPostion.Subtract(CamTarget);
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(currentView.M12, currentView.M22, currentView.M32), angleY)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
break;
case Keys.Up:
CamPostion.Subtract(CamTarget);
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(m_device.Transform.View.M11
, m_device.Transform.View.M21, m_device.Transform.View.M31), -angleY)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
break;
case Keys.Down:
CamPostion.Subtract(CamTarget);
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(m_device.Transform.View.M11
, m_device.Transform.View.M21, m_device.Transform.View.M31), angleY)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
break;
case Keys.Add:
CamPostion.Subtract(CamTarget);
CamPostion.Scale(0.95f);
CamPostion.Add(CamTarget);
break;
case Keys.Subtract:
CamPostion.Subtract(CamTarget);
CamPostion.Scale(1.05f);
CamPostion.Add(CamTarget);
break;
}
Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.View = viewMatrix;
Render();
}

private void OnMouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
mouseLastX = e.X;
mouseLastY = e.Y;
isRotateByMouse = true;
}
else if (e.Button == MouseButtons.Middle)
{
mouseLastX = e.X;
mouseLastY = e.Y;
isMoveByMouse = true;
}
}

private void OnMouseUp(object sender, MouseEventArgs e)
{
isRotateByMouse = false;
isMoveByMouse = false;
}

private void OnMouseMove(object sender, MouseEventArgs e)
{
if (isRotateByMouse)
{
Matrix currentView = m_device.Transform.View;//当前摄像机的视图矩阵
float tempAngleY = 2 * (float)(e.X - mouseLastX) / this.Width;
CamPostion.Subtract(CamTarget);

Vector4 tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(currentView.M12, currentView.M22, currentView.M32), tempAngleY)));
CamPostion.X = tempV4.X;
CamPostion.Y = tempV4.Y;
CamPostion.Z = tempV4.Z;

float tempAngleX = 4 * (float)(e.Y - mouseLastY) / this.Height;
tempV4 = Vector3.Transform(CamPostion, Matrix.RotationQuaternion(
Quaternion.RotationAxis(new Vector3(currentView.M11, currentView.M21, currentView.M31), tempAngleX)));
CamPostion.X = tempV4.X + CamTarget.X;
CamPostion.Y = tempV4.Y + CamTarget.Y;
CamPostion.Z = tempV4.Z + CamTarget.Z;
Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.View = viewMatrix;

mouseLastX = e.X;
mouseLastY = e.Y;
Render();
}
else if (isMoveByMouse)
{
Matrix currentView = m_device.Transform.View;//当前摄像机的视图矩阵
float moveFactor = 0.01f;
CamTarget.X += -moveFactor * ((e.X - mouseLastX) * currentView.M11 - (e.Y - mouseLastY) * currentView.M12);
CamTarget.Y += -moveFactor * ((e.X - mouseLastX) * currentView.M21 - (e.Y - mouseLastY) * currentView.M22);
CamTarget.Z += -moveFactor * ((e.X - mouseLastX) * currentView.M31 - (e.Y - mouseLastY) * currentView.M32);

CamPostion.X += -moveFactor * ((e.X - mouseLastX) * currentView.M11 - (e.Y - mouseLastY) * currentView.M12);
CamPostion.Y += -moveFactor * ((e.X - mouseLastX) * currentView.M21 - (e.Y - mouseLastY) * currentView.M22);
CamPostion.Z += -moveFactor * ((e.X - mouseLastX) * currentView.M31 - (e.Y - mouseLastY) * currentView.M32);

Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.View = viewMatrix;
mouseLastX = e.X;
mouseLastY = e.Y;
Render();
}
}
private void OnMouseWheel(object sender, MouseEventArgs e)
{
float scaleFactor = -(float)e.Delta / 2000 + 1f;
CamPostion.Subtract(CamTarget);
CamPostion.Scale(scaleFactor);
CamPostion.Add(CamTarget);
Matrix viewMatrix = Matrix.LookAtLH(CamPostion, CamTarget, new Vector3(0, 1, 0));
m_device.Transform.View = viewMatrix;
Render();
}
}
}