DirectX 3D纹理
纹理就是3D模型外表面上的图案。在3D场景中纹理极大地增加了物体的真实性。纹理的本质是把平面图形贴到3D物体表面。在Direct3D中纹理的x和y坐标一般称为Tu和Tv坐标，纹理坐标范围都是0.0-1.0。如果知道一个面的顶点坐标，使面的顶点坐标和句型图片纹理坐标相对应，就可以将这些二维图片贴到3D图形表面。在Direct 3D中Texture类定义纹理。
如果希望为墙壁贴上瓷砖，可以只绘制一个瓷砖的平面图形，然后把瓷砖图形自动平铺到墙壁上。这里运用了Direct 3D默认的寻址模式TextureAddress.Wrap，如果纹理的x坐标大于1，例如为n，表示图片沿X轴方向重复贴图n次。
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 墙壁贴瓷砖
{
public partial class Form1 : Form
{
private Device device = null;
bool pause = false;
VertexBuffer vertexBuffer1 = null;
Texture texture = null;
public Form1()
{
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;
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
device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(device, null);//自定义方法，初始化Device的工作放到这个方法中
this.OnResetDevice(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;
vertexBuffer1 = new VertexBuffer(typeof(CustomVertex.PositionTextured), 6, dev, 0, CustomVertex.PositionTextured.Format, Pool.Default);
vertexBuffer1.Created += new EventHandler(vertexBuffer1_Created);
this.vertexBuffer1_Created(vertexBuffer1, null);
texture = TextureLoader.FromFile(dev, Application.StartupPath + @"\..\..\..\p2.bmp");
}
public void OnResetDevice(object sender, EventArgs e)
{
Device dev = (Device)sender;
dev.RenderState.CullMode = Cull.None; //取消背面剔除
dev.RenderState.Lighting = false; //取消灯光
SetupMatrices(); //在程序运行期间，Device的3个变换不改变，因此放在此处
}
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 (device == null) //如果未建立设备对象，退出
return;
if (pause)
return;
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.LightCoral, 1.0f, 0);
device.BeginScene();//开始渲染
SetupMatrices();
device.SetTexture(0, texture); //为Device类对象device增加使用的第0个纹理
device.SetStreamSource(0, vertexBuffer1, 0);
device.VertexFormat = CustomVertex.PositionTextured.Format;
device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);
device.EndScene(); //渲染结束
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 void Form1_Paint(object sender, PaintEventArgs e)
{
this.Render();
}
private void Form1_Resize(object sender, EventArgs e)
{
pause = ((this.WindowState == FormWindowState.Minimized) || !this.Visible);
}
void vertexBuffer1_Created(object sender, EventArgs e)
{
CustomVertex.PositionTextured[] verts =
(CustomVertex.PositionTextured[])vertexBuffer1.Lock(0, 0);//墙壁
verts[0].Position = new Vector3(-2.0f, -2.0f, 2.0f); //顶点0位置
verts[0].Tu = 0.0f; //顶点0纹理坐标Tu
verts[0].Tv = 10.0f;
verts[1].Position = new Vector3(-2.0f, 2.0f, 2.0f); //顶点1位置
verts[1].Tu = 0.0f; //顶点1纹理坐标Tu
verts[1].Tv = 0.0f;
verts[2].Position = new Vector3(2.0f, 2.0f, 2.0f); //顶点2位置
verts[2].Tu = 10.0f; //顶点2纹理坐标Tu
verts[2].Tv = 0.0f;
verts[3].Position = new Vector3(-2.0f, -2.0f, 2.0f); //顶点3位置
verts[3].Tu = 0.0f; //顶点3纹理坐标Tu
verts[3].Tv = 10.0f;
verts[4].Position = new Vector3(2.0f, 2.0f, 2.0f); //顶点4位置
verts[4].Tu = 10.0f; //顶点4纹理坐标Tu
verts[4].Tv = 0.0f;
verts[5].Position = new Vector3(2.0f, -2.0f, 2.0f); //顶点5位置
verts[5].Tu = 10.0f; //顶点5纹理坐标Tu
verts[5].Tv = 10.0f;
vertexBuffer1.Unlock();
}
private void SetupMatrices() //修改Device的3个变换
{
device.Transform.World = Matrix.RotationY(0); //世界变换矩阵
device.Transform.View = Matrix.LookAtLH(new Vector3(0.0f, 0.0f, -4.0f), new Vector3(0.0f, 0.0f, 0.0f), new Vector3(0.0f, 1.0f, 0.0f));
device.Transform.Projection = Matrix.PerspectiveFovLH((float)Math.PI / 4, 1.0f, 1.0f, 100.0f); //投影变换矩阵
}
private void Form1_Load(object sender, EventArgs e)
{
InitializeGraphics();
this.Show();
Render();
}
}
}
为有光照的空心圆柱增加纹理，此时还需要考虑光照的影响。Device类对象的TextureState数组记录了每一个纹理的状态，允许多层纹理，数组的索引值为0~7，其属性ColorOperation记录了该元素所代表的纹理图片颜色和其他参数(e.g.光照颜色)的混合方法；属性ColorArgument1和ColorArgument2用来指定属性ColorOperation使用的参数
实现如下：
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 为空心圆柱增加纹理
{
public partial class Form1 : Form
{
private Device device = null;
bool pause = false;
VertexBuffer vertexBuffer = null;
Material mtrl;
Texture texture = null;
public Form1()
{
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;
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
device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(device, null);//自定义方法，初始化Device的工作放到这个方法中
this.OnResetDevice(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; //注意阴影部分
vertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionNormalTextured), 100, dev,
Usage.WriteOnly, CustomVertex.PositionNormalTextured.Format, Pool.Default);
vertexBuffer.Created += new System.EventHandler(this.OnCreateVertexBuffer);
this.OnCreateVertexBuffer(vertexBuffer, null);
mtrl = new Material();
mtrl.Diffuse = System.Drawing.Color.Yellow; //物体的颜色
mtrl.Ambient = System.Drawing.Color.Red; //反射环境光的颜色
texture = TextureLoader.FromFile(dev, Application.StartupPath + @"\..\..\..\p1.JPG");
}
public void OnResetDevice(object sender, EventArgs e)
{
Device dev = (Device)sender;
dev.RenderState.CullMode = Cull.None; //取消背面剔除
device.RenderState.ZBufferEnable = true; //打开Z缓冲
device.RenderState.Lighting = true; //打开灯光
SetupLights(); //设置灯光
}
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 (device == null) //如果未建立设备对象，退出
return;
if (pause)
return;
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.WhiteSmoke, 1.0f, 0);
SetupMatrices();
device.BeginScene(); //开始渲染
device.SetTexture(0, texture);
device.TextureState[0].ColorOperation = TextureOperation.Modulate;
device.TextureState[0].ColorArgument1 = TextureArgument.TextureColor;//纹理颜色
device.TextureState[0].ColorArgument2 = TextureArgument.Diffuse;//光照颜色
device.TextureState[0].AlphaOperation = TextureOperation.Disable;
device.SetStreamSource(0, vertexBuffer, 0);
device.VertexFormat = CustomVertex.PositionNormalTextured.Format;
device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, (4 * 25) - 2);
device.EndScene();//渲染结束
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 void Form1_Paint(object sender, PaintEventArgs e)
{
this.Render();
}
private void Form1_Resize(object sender, EventArgs e)
{
pause = ((this.WindowState == FormWindowState.Minimized) || !this.Visible);
}
public void OnCreateVertexBuffer(object sender, EventArgs e)
{
CustomVertex.PositionNormalTextured[] verts =
(CustomVertex.PositionNormalTextured[])vertexBuffer.Lock(0, 0);
for (int i = 0; i < 50; i++)
{
float theta = (float)(2 * Math.PI * i) / 49;
verts[2 * i].Position = new Vector3((float)Math.Sin(theta), -1, (float)Math.Cos(theta));
verts[2 * i].Normal = new Vector3((float)Math.Sin(theta), 0, (float)Math.Cos(theta));
verts[2 * i].Tu = ((float)i) / (50 - 1);
verts[2 * i].Tv = 1.0f;
verts[2 * i + 1].Position = new Vector3((float)Math.Sin(theta), 1, (float)Math.Cos(theta));
verts[2 * i + 1].Normal = new Vector3((float)Math.Sin(theta), 0, (float)Math.Cos(theta));
verts[2 * i + 1].Tu = ((float)i) / (50 - 1);
verts[2 * i + 1].Tv = 0.0f;
}
vertexBuffer.Unlock();
}
private void SetupMatrices()
{
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);
device.Transform.View = Matrix.LookAtLH(new Vector3(0.0f, 3.0f, -5.0f),
new Vector3(0.0f, 0.0f, 0.0f), new Vector3(0.0f, 1.0f, 0.0f));
device.Transform.Projection = Matrix.PerspectiveFovLH((float)Math.PI / 4, 1.0f, 1.0f, 100.0f);
}
private void SetupLights()
{
device.Material = mtrl;
device.Lights[0].Type = LightType.Directional;
device.Lights[0].Diffuse = System.Drawing.Color.White;
device.Lights[0].Direction = new Vector3((float)Math.Cos(Environment.TickCount / 250.0f),
1.0f, (float)Math.Sin(Environment.TickCount / 250.0f));
device.Lights[0].Enabled = true;
device.RenderState.Ambient = System.Drawing.Color.FromArgb(0x404040);
}
private void Form1_load(object sender, EventArgs e)
{
InitializeGraphics();
this.Show();
Render();
}
}
}
可以为上面的空心圆柱添加背景，所谓的背景就是固定不动的图像，也就是在进行三个变换时，背景位置不变。
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 空心圆柱添加背景
{
public partial class Form1 : Form
{
private Device device = null;
bool pause = false;
VertexBuffer vertexBuffer = null;
Material mtrl;
Texture texture = null;
VertexBuffer vertexBuffer1 = null;
Texture texture1 = null;
public Form1()
{
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;
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
device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(device, null);//自定义方法，初始化Device的工作放到这个方法中
this.OnResetDevice(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; //阴影部分是所作的修改
vertexBuffer = new VertexBuffer(typeof(CustomVertex.PositionNormalTextured), 100, dev,
Usage.WriteOnly, CustomVertex.PositionNormalTextured.Format, Pool.Default);
vertexBuffer.Created += new System.EventHandler(this.OnCreateVertexBuffer);
this.OnCreateVertexBuffer(vertexBuffer, null);
mtrl = new Material();
mtrl.Diffuse = System.Drawing.Color.Yellow; //物体的颜色
mtrl.Ambient = System.Drawing.Color.Red; //反射环境光的颜色
texture = TextureLoader.FromFile(dev, Application.StartupPath + @"\..\..\..\p1.JPG");
vertexBuffer1 = new VertexBuffer(typeof(CustomVertex.TransformedTextured), 4, dev, 0, CustomVertex.TransformedTextured.Format, Pool.Default);
vertexBuffer1.Created += new EventHandler(vertexBuffer1_Created);
this.vertexBuffer1_Created(vertexBuffer1, null);
texture1 = TextureLoader.FromFile(dev, Application.StartupPath + @"\..\..\..\p2.jpg");
}
public void OnResetDevice(object sender, EventArgs e)
{
Device dev = (Device)sender;
dev.RenderState.CullMode = Cull.None; //取消背面剔除
device.RenderState.ZBufferEnable = true; //打开Z缓冲
device.RenderState.Lighting = true; //打开灯光
SetupLights();
}
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 (device == null) //如果未建立设备对象，退出
return;
if (pause)
return;
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.WhiteSmoke, 1.0f, 0);
SetupMatrices();
device.BeginScene(); //开始渲染
device.SetTexture(0, texture1); //这段代码必须放在渲染圆柱体代码之前
device.RenderState.ZBufferEnable = false;
device.SetStreamSource(0, vertexBuffer1, 0);
device.VertexFormat = CustomVertex.TransformedTextured.Format;
device.DrawPrimitives(PrimitiveType.TriangleFan, 0, 2);
device.RenderState.ZBufferEnable = true;
device.SetTexture(0, texture);
device.TextureState[0].ColorOperation = TextureOperation.Modulate;
device.TextureState[0].ColorArgument1 = TextureArgument.TextureColor;
device.TextureState[0].ColorArgument2 = TextureArgument.Diffuse;
device.TextureState[0].AlphaOperation = TextureOperation.Disable;
device.SetStreamSource(0, vertexBuffer, 0);
device.VertexFormat = CustomVertex.PositionNormalTextured.Format;
device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, (4 * 25) - 2);
device.EndScene(); //渲染结束
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 void Form1_Paint(object sender, PaintEventArgs e)
{
this.Render();
}
private void Form1_Resize(object sender, EventArgs e)
{
pause = ((this.WindowState == FormWindowState.Minimized) || !this.Visible);
}
public void OnCreateVertexBuffer(object sender, EventArgs e)
{
CustomVertex.PositionNormalTextured[] verts =
(CustomVertex.PositionNormalTextured[])vertexBuffer.Lock(0, 0);
for (int i = 0; i < 50; i++)
{
float theta = (float)(2 * Math.PI * i) / 49;
verts[2 * i].Position = new Vector3((float)Math.Sin(theta), -1, (float)Math.Cos(theta));
verts[2 * i].Normal = new Vector3((float)Math.Sin(theta), 0, (float)Math.Cos(theta));
verts[2 * i].Tu = ((float)i) / (50 - 1);
verts[2 * i].Tv = 1.0f;
verts[2 * i + 1].Position = new Vector3((float)Math.Sin(theta), 1, (float)Math.Cos(theta));
verts[2 * i + 1].Normal = new Vector3((float)Math.Sin(theta), 0, (float)Math.Cos(theta));
verts[2 * i + 1].Tu = ((float)i) / (50 - 1);
verts[2 * i + 1].Tv = 0.0f;
}
vertexBuffer.Unlock();
}
private void SetupMatrices()
{
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);
device.Transform.View = Matrix.LookAtLH(new Vector3(0.0f, 3.0f, -5.0f),
new Vector3(0.0f, 0.0f, 0.0f), new Vector3(0.0f, 1.0f, 0.0f));
device.Transform.Projection = Matrix.PerspectiveFovLH((float)Math.PI / 4, 1.0f, 1.0f, 100.0f);
}
private void SetupLights()
{
device.Material = mtrl;
device.Lights[0].Type = LightType.Directional;
device.Lights[0].Diffuse = System.Drawing.Color.White;
device.Lights[0].Direction = new Vector3((float)Math.Cos(Environment.TickCount / 250.0f),
1.0f, (float)Math.Sin(Environment.TickCount / 250.0f));
device.Lights[0].Enabled = true;
device.RenderState.Ambient = System.Drawing.Color.FromArgb(0x404040);
}
void vertexBuffer1_Created(object sender, EventArgs e)
{
CustomVertex.TransformedTextured[] verts =
(CustomVertex.TransformedTextured[])vertexBuffer1.Lock(0, 0);
verts[0].Position = new Vector4(0, 0, 0, 1);
verts[0].Tu = 0.0f;
verts[0].Tv = 0.0f;
verts[1].Position = new Vector4(this.Width, 0, 0, 1);
verts[1].Tu = 1.0f;
verts[1].Tv = 0.0f;
verts[2].Position = new Vector4(this.Width, this.Height, 0, 1);
verts[2].Tu = 1.0f;
verts[2].Tv = 1.0f;
verts[3].Position = new Vector4(0, this.Height, 0, 1);
verts[3].Tu = 0.0f;
verts[3].Tv = 1.0f;
vertexBuffer1.Unlock();
}
private void Form1_Load(object sender, EventArgs e)
{
InitializeGraphics();
this.Show();
Render();
}
}
}
为正方形增加纹理，如果正方形尺寸较大，而纹理的分辨率较低，这时纹理图像可能要出现马赛克，如果正方形尺寸较大，而纹理图片分辨率较高时，此时要缩小图形以适应正方形尺寸。为了解决这个问题，可以使用纹理滤波器，纹理滤波器的本质是数学差值。3D图形的表面可以贴多个图片，称为多层纹理。为正方形增加两个纹理，一个是一面不规则的墙的图案，另一个是一个光影。多纹理的混合需要一个是半透明的，两个混合后才有效果，通过设置纹理0的混合方法，再设置纹理1的混合方法，然后再把纹理0图案的颜色设置为半透明的即可。
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 正方形添加多纹理
{
public partial class Form1 : Form
{
private Device device = null;
bool pause = false;
VertexBuffer vertexBuffer1 = null;
Texture texture = null;
Texture texture1 = null;
public Form1()
{
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;
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
device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(device, null);//自定义方法，初始化Device的工作放到这个方法中
this.OnResetDevice(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; //注意有阴影部分
vertexBuffer1 = new VertexBuffer(typeof(CustomVertex.PositionTextured), 6, dev, 0,
CustomVertex.PositionTextured.Format, Pool.Default);
vertexBuffer1.Created += new EventHandler(vertexBuffer1_Created);
this.vertexBuffer1_Created(vertexBuffer1, null);
texture = TextureLoader.FromFile(dev, Application.StartupPath + @"\..\..\..\p1.bmp");
texture1 = TextureLoader.FromFile(dev, Application.StartupPath + @"\..\..\..\p2.bmp");
}
public void OnResetDevice(object sender, EventArgs e)
{
Device dev = (Device)sender;
dev.RenderState.CullMode = Cull.None; //取消背面剔除
dev.RenderState.Lighting = false; //取消灯光
SetupMatrices(); //在程序运行期间，Device的3个变换不改变，因此放在此处
device.SamplerState[0].MagFilter = TextureFilter.Linear; //使用线性滤波器
}
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 (device == null) //如果未建立设备对象，退出
return;
if (pause)
return;
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.Blue, 1.0f, 0);
device.BeginScene(); //开始渲染
device.SetTexture(0, texture); //索引号为0的纹理是墙壁图案
device.SetTexture(1, texture1); //索引号为1的纹理是光影图案
device.TextureState[0].TextureCoordinateIndex = 0; //纹理坐标Tu和Tv初始值
device.TextureState[1].TextureCoordinateIndex = 0;
device.SamplerState[0].MagFilter = TextureFilter.Linear; //放大图形使用线形滤波器
device.SamplerState[1].MagFilter = TextureFilter.Linear; //缩小图形使用线形滤波器
device.TextureState[0].ColorOperation = TextureOperation.SelectArg1;
device.TextureState[0].ColorArgument1 = TextureArgument.TextureColor;
//以下两句设置纹理0为半透明的，和纹理1混合后能看到混合效果，透明效果见10.2节
device.TextureState[0].AlphaOperation = TextureOperation.SelectArg1;
device.TextureState[0].AlphaArgument1 = TextureArgument.TextureColor;
device.TextureState[1].ColorOperation = TextureOperation.Modulate;
device.TextureState[1].ColorArgument1 = TextureArgument.TextureColor;
device.TextureState[1].ColorArgument2 = TextureArgument.Current;
//device.TextureState[1].AlphaOperation = TextureOperation.Disable;
//device.TextureState[2].ColorOperation = TextureOperation.Disable;
//device.TextureState[2].AlphaOperation = TextureOperation.Disable;
device.SetStreamSource(0, vertexBuffer1, 0);
device.VertexFormat = CustomVertex.PositionTextured.Format;
device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);
device.EndScene(); //渲染结束
device.Present(); //更新显示区域，把后备缓存的图形送到图形卡的显存中显示
}
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);
}
void vertexBuffer1_Created(object sender, EventArgs e)
{
CustomVertex.PositionTextured[] verts =
(CustomVertex.PositionTextured[])vertexBuffer1.Lock(0, 0); //墙壁
verts[0].Position = new Vector3(-2.0f, -2.0f, 2.0f); //顶点0位置
verts[0].Tu = 0.0f; //顶点0纹理坐标Tu
verts[0].Tv = 1.0f;
verts[1].Position = new Vector3(-2.0f, 2.0f, 2.0f); //顶点1位置
verts[1].Tu = 0.0f; //顶点1纹理坐标Tu
verts[1].Tv = 0.0f;
verts[2].Position = new Vector3(2.0f, 2.0f, 2.0f); //顶点2位置
verts[2].Tu = 1.0f; //顶点2纹理坐标Tu
verts[2].Tv = 0.0f;
verts[3].Position = new Vector3(-2.0f, -2.0f, 2.0f); //顶点3位置
verts[3].Tu = 0.0f; //顶点3纹理坐标Tu
verts[3].Tv = 1.0f;
verts[4].Position = new Vector3(2.0f, 2.0f, 2.0f); //顶点4位置
verts[4].Tu = 1.0f; //顶点4纹理坐标Tu
verts[4].Tv = 0.0f;
verts[5].Position = new Vector3(2.0f, -2.0f, 2.0f); //顶点5位置
verts[5].Tu = 1.0f; //顶点5纹理坐标Tu
verts[5].Tv = 1.0f;
vertexBuffer1.Unlock();
}
private void SetupMatrices() //修改Device的3个变换
{
device.Transform.World = Matrix.RotationY(0); //世界变换矩阵
device.Transform.View = Matrix.LookAtLH(new Vector3(0.0f, 0.0f, -4.0f), new Vector3(0.0f, 0.0f, 0.0f), new Vector3(0.0f, 1.0f, 0.0f));
device.Transform.Projection = Matrix.PerspectiveFovLH((float)Math.PI / 4, 1.0f, 1.0f, 100.0f); //投影变换矩阵
}
private void Form1_Load(object sender, EventArgs e)
{
InitializeGraphics();
this.Show();
Render();
}
}
}
在程序运行时有时需要多个不同分辨率的同一张图片，以适合大小不同的物体表面贴图用，当物体离观察者近的适合使用高质量的纹理，而物体离观察者远的时候使用低分辨率的纹理。这时就需要使用多级渐进纹理来控制渲染时纹理的质量，但是这样做的代价是会吃掉更多的内存。