DirectX 3D 之C#开发

C#下进行directX的3D开发，一个旋转的4棱锥的例子。

建议看两个文档<Managed DirectX 9图形和游戏编程简略中文文档>和<Managed DirectX 9 SDK 中文文档>。

另外最好下载个DirectX SDK (August 2007).rar。里面有些范例还是非常好的。

一、首先在电脑上装了DirectX。

二、建立一个C#的Windows应用程序，添加两个引用Microsoft.DirectX和Microsoft.DirectX.Direct3D;

三、Form1.cs

具体代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using Microsoft.DirectX;          //开发directx需要包含的两个命名空间
using Microsoft.DirectX.Direct3D;

namespace Rectangle
{
    public partial class form1 : Form
    {
        
        /// <summary>
        /// 设备对象，场景中所有图形对象的父对象
        /// </summary>
        private Device device = null;

/// <summary>
        /// 坐标系四棱锥顶点缓冲
        /// </summary>
        VertexBuffer vertexBuffer = null;

/// <summary>
        /// 此参数设置为必须，它定义了要创建的Direct3D设备的表示参数，如后台缓冲区的高度、宽度和像素格式、如何从后台缓冲区复制到前台缓存、以及屏幕显示的方式等等
        /// </summary>
        PresentParameters presentParameters = new PresentParameters();
        
        /// <summary>
        /// 暂停标志
        /// </summary>
        bool pause = false;

/// <summary>
        /// 随机数，用来生成随机颜色用的
        /// </summary>
        Random rn = new Random();

/// <summary>
        /// 构造函数，设置窗体大小
        /// </summary>
        public form1()
        {
            this.ClientSize = new System.Drawing.Size(300, 300);
        }

/// <summary>
        /// 初始化绘图环境
        /// </summary>
        /// <returns></returns>
        public bool InitializeGraphics()
        {
            try
            {
                //设置屏幕显示模式为窗口模式
                presentParameters.Windowed = true;
                //设置如何从后台缓冲区复制到前台缓冲区(SwapEffect.Discard表示缓冲区在显示后立即被舍弃,这样可以节省开销)
                presentParameters.SwapEffect = SwapEffect.Discard;
                //创建一个设备
                device = new Device(0, DeviceType.Hardware, this, CreateFlags.SoftwareVertexProcessing, presentParameters);
                //为设备释放订阅事件处理
                device.DeviceReset += new System.EventHandler(this.OnResetDevice);
                
                this.OnCreateDevice(device, null);
                this.OnResetDevice(device, null);
                pause = false;
                return true;
            }

catch (DirectXException)
            {
                return false;
            }
        }

/// <summary>
        /// 设备创建时建立顶点缓冲
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void OnCreateDevice(object sender, EventArgs e)
        {
            Device dev = (Device)sender;

//创建顶点缓冲,有个顶点
            vertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionColored), 18, dev, 0, CustomVertex.PositionColored.Format, Pool.Default);
            //为创建顶点缓存订阅事件处理
            vertexBuffer.Created += new System.EventHandler(this.OnCreateVertexBuffer);

this.OnCreateVertexBuffer(vertexBuffer, null);
        }

/// <summary>
        /// 设备撤销的事件处理
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void OnResetDevice(object sender, EventArgs e)
        {
            Device dev = (Device)sender;
            //关闭剔除模式，使我们能看见此四棱锥的前面和后面
            dev.RenderState.CullMode = Cull.None;
            // 关闭场景里的灯光，显示顶点自己的颜色
            dev.RenderState.Lighting = false;
        }

/// <summary>
        /// 创建顶点缓存的事件处理
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void OnCreateVertexBuffer(object sender, EventArgs e)
        {
            
            VertexBuffer vb = (VertexBuffer)sender;
            CustomVertex.PositionColored[] verts = (CustomVertex.PositionColored[])vb.Lock(0, 0);
            
            //四棱锥原始的个点
            Vector3 vertex1 = new Vector3(25, 0, 0);
            Vector3 vertex2 = new Vector3(0, 0, -25);
            Vector3 vertex3 = new Vector3(-25, 0, 0);
            Vector3 vertex4 = new Vector3(0, 0, 25);
            Vector3 vertex5 = new Vector3(0, 25, 0);

//四棱锥中包含个三角形，所以要构造个点来绘制
            verts[0].Position = vertex1;
            verts[1].Position = vertex2;
            verts[2].Position = vertex5;
            verts[3].Position = vertex2;
            verts[4].Position = vertex3;
            verts[5].Position = vertex5;
            verts[6].Position = vertex3;
            verts[7].Position = vertex4;
            verts[8].Position = vertex5;
            verts[9].Position = vertex4;
            verts[10].Position = vertex1;
            verts[11].Position = vertex5;
            verts[12].Position = vertex2;
            verts[13].Position = vertex1;
            verts[14].Position = vertex3;
            verts[15].Position = vertex3;
            verts[16].Position = vertex1;
            verts[17].Position = vertex4;

//给每个点赋予随机颜色
            for (int i = 0; i < 18; i++)
            {
                verts[i].Color = Color.FromArgb(SetColor(), SetColor(), SetColor()).ToArgb();

}
                vb.Unlock();

}

/// <summary>
        /// 返回到之间的一个随机数，用来生成随机颜色
        /// </summary>
        /// <returns></returns>
        public int SetColor()
        {
            int number = rn.Next(256);
            return number;
        }

/// <summary>
        /// 设置摄像机的位置
        /// </summary>
        private void SetupCamera()
        {
            //设置世界矩阵，根据系统运行时间而变化
            device.Transform.World = Matrix.RotationAxis(new Vector3((float)Math.Cos(Environment.TickCount / 250.0f), 1, (float)Math.Sin(Environment.TickCount / 250.0f)), Environment.TickCount / 3000.0f);
            //设置摄像机的位置，它在z轴上-50处，看着原点，y轴为正方向
            device.Transform.View = Matrix.LookAtLH(new Vector3(0.0f, 0.0f, -50f), new Vector3(0.0f, 0.0f, 0.0f), new Vector3(0.0f, 1.0f, 0.0f));

//设置摄像机的视界，角度为度，看的最近为,看的最远处为.不再这个视界中的影像都不会被显示
            device.Transform.Projection = Matrix.PerspectiveFovLH(((float)(float)Math.PI / 2 ), 1.0f, 10.0f, 200.0f);
        }

/// <summary>
        /// 绘制图形
        /// </summary>
        public void Render()
        {
            if (device == null)
                return;

if (pause)
                return;

//背景设为绿色
            device.Clear(ClearFlags.Target, System.Drawing.Color.Blue, 1.0f, 0);
            //开始场景
            device.BeginScene();
            // 设置世界，视野和投影矩阵
            SetupCamera();

// 给设备指定顶点缓存
            device.SetStreamSource(0, vertexBuffer, 0);

//设置设备的顶点格式
            device.VertexFormat = CustomVertex.PositionColored.Format;

//绘制图形，使用的方法为三角形列表，个数为个
            device.DrawPrimitives(PrimitiveType.TriangleList, 0, 6);
                        
            //结束场景
            device.EndScene();

//更新场景
            device.Present();
        }

//重载OnPaint函数
        protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
        {
            //绘制图形
            this.Render(); 
        }
    }
}

四，program.cs中的代码为：

using System;
using System.Collections.Generic;
using System.Windows.Forms;

namespace Rectangle
{
    static class Program
    {
        /// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main()
        {
            using (form1 frm = new form1())
            {

if (!frm.InitializeGraphics()) // 初始化 Direct3D
                {
                    MessageBox.Show("不能初始化 Direct3D.程序将退出.");
                    return;
                }
                frm.Show();

// While the form is still valid, render and process messages
                while (frm.Created)
                {
                    frm.Render();
                    Application.DoEvents(); //处理当前在消息队列中的所有 Windows 消息
                }
            }
        }
    }
}

运行后你会看到一个不断旋转的四棱锥。