紋理就是3D模型外表面上的圖案。在3D場景中紋理極大地增加了物體的真實性。紋理的本質是把平面圖形貼到3D物體表面。在Direct3D中紋理的x和y座標一般稱爲Tu和Tv座標，紋理座標範圍都是0.0-1.0。如果知道一個面的頂點座標，使面的頂點座標和句型圖片紋理座標相對應，就可以將這些二維圖片貼到3D圖形表面。在Direct 3D中Texture類定義紋理。
如果希望爲牆壁貼上瓷磚，可以只繪製一個瓷磚的平面圖形，然後把瓷磚圖形自動平鋪到牆壁上。這裏運用了Direct 3D默認的尋址模式TextureAddress.Wrap，如果紋理的x座標大於1，例如爲n，表示圖片沿X軸方向重複貼圖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 牆壁貼瓷磚
{
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; //不是全屏顯示，在一個窗口顯示
presentParams.SwapEffect = SwapEffect.Discard; //後備緩存交換的方式
presentParams.EnableAutoDepthStencil = true; //允許使用自動深度模板測試
//深度緩衝區單元爲16位二進制數
presentParams.AutoDepthStencilFormat = DepthFormat.D16;
device = new Device(0, DeviceType.Hardware, this, //建立設備類對象
CreateFlags.SoftwareVertexProcessing, presentParams);
//設置設備重置事件(device.DeviceReset)事件函數爲this.OnResetDevice
device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(device, null);//自定義方法，初始化Device的工作放到這個方法中
this.OnResetDevice(device, null);//調用設備重置事件(device.DeviceReset)事件函數
} //設備重置事件函數要設置Device參數，初始函數中必須調用該函數
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; //取消燈光
SetupMatrices(); //在程序運行期間，Device的3個變換不改變，因此放在此處
}
public void Render() //渲染方法，本方法沒有任何渲染代碼，可認爲是渲染方法的框架
{
if (device == null) //如果未建立設備對象，退出
return;
if (pause)
return;
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.LightCoral, 1.0f, 0);
device.BeginScene();//開始渲染
SetupMatrices();
device.SetTexture(0, texture); //爲Device類對象device增加使用的第0個紋理
device.SetStreamSource(0, vertexBuffer1, 0);
device.VertexFormat = CustomVertex.PositionTextured.Format;
device.DrawPrimitives(PrimitiveType.TriangleList, 0, 2);
device.EndScene(); //渲染結束
device.Present(); //更新顯示區域，把後備緩存的D圖形送到圖形卡的顯存中顯示
}
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);//牆壁
verts[0].Position = new Vector3(-2.0f, -2.0f, 2.0f); //頂點0位置
verts[0].Tu = 0.0f; //頂點0紋理座標Tu
verts[0].Tv = 10.0f;
verts[1].Position = new Vector3(-2.0f, 2.0f, 2.0f); //頂點1位置
verts[1].Tu = 0.0f; //頂點1紋理座標Tu
verts[1].Tv = 0.0f;
verts[2].Position = new Vector3(2.0f, 2.0f, 2.0f); //頂點2位置
verts[2].Tu = 10.0f; //頂點2紋理座標Tu
verts[2].Tv = 0.0f;
verts[3].Position = new Vector3(-2.0f, -2.0f, 2.0f); //頂點3位置
verts[3].Tu = 0.0f; //頂點3紋理座標Tu
verts[3].Tv = 10.0f;
verts[4].Position = new Vector3(2.0f, 2.0f, 2.0f); //頂點4位置
verts[4].Tu = 10.0f; //頂點4紋理座標Tu
verts[4].Tv = 0.0f;
verts[5].Position = new Vector3(2.0f, -2.0f, 2.0f); //頂點5位置
verts[5].Tu = 10.0f; //頂點5紋理座標Tu
verts[5].Tv = 10.0f;
vertexBuffer1.Unlock();
}
private void SetupMatrices() //修改Device的3個變換
{
device.Transform.World = Matrix.RotationY(0); //世界變換矩陣
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); //投影變換矩陣
}
private void Form1_Load(object sender, EventArgs e)
{
InitializeGraphics();
this.Show();
Render();
}
}
}
爲有光照的空心圓柱增加紋理，此時還需要考慮光照的影響。Device類對象的TextureState數組記錄了每一個紋理的狀態，允許多層紋理，數組的索引值爲0~7，其屬性ColorOperation記錄了該元素所代表的紋理圖片顏色和其他參數(e.g.光照顏色)的混合方法；屬性ColorArgument1和ColorArgument2用來指定屬性ColorOperation使用的參數
實現如下：
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 爲空心圓柱增加紋理
{
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; //不是全屏顯示，在一個窗口顯示
presentParams.SwapEffect = SwapEffect.Discard; //後備緩存交換的方式
presentParams.EnableAutoDepthStencil = true; //允許使用自動深度模板測試
//深度緩衝區單元爲16位二進制數
presentParams.AutoDepthStencilFormat = DepthFormat.D16;
device = new Device(0, DeviceType.Hardware, this, //建立設備類對象
CreateFlags.SoftwareVertexProcessing, presentParams);
//設置設備重置事件(device.DeviceReset)事件函數爲this.OnResetDevice
device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(device, null);//自定義方法，初始化Device的工作放到這個方法中
this.OnResetDevice(device, null);//調用設備重置事件(device.DeviceReset)事件函數
} //設備重置事件函數要設置Device參數，初始函數中必須調用該函數
catch (DirectXException)
{
return false;
}
return true;
}
public void OnCreateDevice(object sender, EventArgs e)
{
Device dev = (Device)sender; //注意陰影部分
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; //物體的顏色
mtrl.Ambient = System.Drawing.Color.Red; //反射環境光的顏色
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; //打開Z緩衝
device.RenderState.Lighting = true; //打開燈光
SetupLights(); //設置燈光
}
public void Render() //渲染方法，本方法沒有任何渲染代碼，可認爲是渲染方法的框架
{
if (device == null) //如果未建立設備對象，退出
return;
if (pause)
return;
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.WhiteSmoke, 1.0f, 0);
SetupMatrices();
device.BeginScene(); //開始渲染
device.SetTexture(0, texture);
device.TextureState[0].ColorOperation = TextureOperation.Modulate;
device.TextureState[0].ColorArgument1 = TextureArgument.TextureColor;//紋理顏色
device.TextureState[0].ColorArgument2 = TextureArgument.Diffuse;//光照顏色
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();//渲染結束
device.Present();//更新顯示區域，把後備緩存的D圖形送到圖形卡的顯存中顯示
}
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();
}
}
}
可以爲上面的空心圓柱添加背景，所謂的背景就是固定不動的圖像，也就是在進行三個變換時，背景位置不變。
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 空心圓柱添加背景
{
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; //不是全屏顯示，在一個窗口顯示
presentParams.SwapEffect = SwapEffect.Discard; //後備緩存交換的方式
presentParams.EnableAutoDepthStencil = true; //允許使用自動深度模板測試
//深度緩衝區單元爲16位二進制數
presentParams.AutoDepthStencilFormat = DepthFormat.D16;
device = new Device(0, DeviceType.Hardware, this, //建立設備類對象
CreateFlags.SoftwareVertexProcessing, presentParams);
//設置設備重置事件(device.DeviceReset)事件函數爲this.OnResetDevice
device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(device, null);//自定義方法，初始化Device的工作放到這個方法中
this.OnResetDevice(device, null);//調用設備重置事件(device.DeviceReset)事件函數
} //設備重置事件函數要設置Device參數，初始函數中必須調用該函數
catch (DirectXException)
{
return false;
}
return true;
}
public void OnCreateDevice(object sender, EventArgs e)
{
Device dev = (Device)sender; //陰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; //物體的顏色
mtrl.Ambient = System.Drawing.Color.Red; //反射環境光的顏色
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; //打開Z緩衝
device.RenderState.Lighting = true; //打開燈光
SetupLights();
}
public void Render() //渲染方法，本方法沒有任何渲染代碼，可認爲是渲染方法的框架
{
if (device == null) //如果未建立設備對象，退出
return;
if (pause)
return;
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.WhiteSmoke, 1.0f, 0);
SetupMatrices();
device.BeginScene(); //開始渲染
device.SetTexture(0, texture1); //這段代碼必須放在渲染圓柱體代碼之前
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(); //渲染結束
device.Present(); //更新顯示區域，把後備緩存的D圖形送到圖形卡的顯存中顯示
}
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();
}
}
}
爲正方形增加紋理，如果正方形尺寸較大，而紋理的分辨率較低，這時紋理圖像可能要出現馬賽克，如果正方形尺寸較大，而紋理圖片分辨率較高時，此時要縮小圖形以適應正方形尺寸。爲了解決這個問題，可以使用紋理濾波器，紋理濾波器的本質是數學差值。3D圖形的表面可以貼多個圖片，稱爲多層紋理。爲正方形增加兩個紋理，一個是一面不規則的牆的圖案，另一個是一個光影。多紋理的混合需要一個是半透明的，兩個混合後纔有效果，通過設置紋理0的混合方法，再設置紋理1的混合方法，然後再把紋理0圖案的顏色設置爲半透明的即可。
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 正方形添加多紋理
{
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; //不是全屏顯示，在一個窗口顯示
presentParams.SwapEffect = SwapEffect.Discard; //後備緩存交換的方式
presentParams.EnableAutoDepthStencil = true; //允許使用自動深度模板測試
//深度緩衝區單元爲16位二進制數
presentParams.AutoDepthStencilFormat = DepthFormat.D16;
device = new Device(0, DeviceType.Hardware, this, //建立設備類對象
CreateFlags.SoftwareVertexProcessing, presentParams);
//設置設備重置事件(device.DeviceReset)事件函數爲this.OnResetDevice
device.DeviceReset += new System.EventHandler(this.OnResetDevice);
this.OnCreateDevice(device, null);//自定義方法，初始化Device的工作放到這個方法中
this.OnResetDevice(device, null);//調用設備重置事件(device.DeviceReset)事件函數
} //設備重置事件函數要設置Device參數，初始函數中必須調用該函數
catch (DirectXException)
{
return false;
}
return true;
}
public void OnCreateDevice(object sender, EventArgs e)
{
Device dev = (Device)sender; //注意有陰影部分
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; //取消燈光
SetupMatrices(); //在程序運行期間，Device的3個變換不改變，因此放在此處
device.SamplerState[0].MagFilter = TextureFilter.Linear; //使用線性濾波器
}
public void Render() //渲染方法，本方法沒有任何渲染代碼，可認爲是渲染方法的框架
{
if (device == null) //如果未建立設備對象，退出
return;
if (pause)
return;
device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, Color.Blue, 1.0f, 0);
device.BeginScene(); //開始渲染
device.SetTexture(0, texture); //索引號爲0的紋理是牆壁圖案
device.SetTexture(1, texture1); //索引號爲1的紋理是光影圖案
device.TextureState[0].TextureCoordinateIndex = 0; //紋理座標Tu和Tv初始值
device.TextureState[1].TextureCoordinateIndex = 0;
device.SamplerState[0].MagFilter = TextureFilter.Linear; //放大圖形使用線形濾波器
device.SamplerState[1].MagFilter = TextureFilter.Linear; //縮小圖形使用線形濾波器
device.TextureState[0].ColorOperation = TextureOperation.SelectArg1;
device.TextureState[0].ColorArgument1 = TextureArgument.TextureColor;
//以下兩句設置紋理0爲半透明的，和紋理1混合後能看到混合效果，透明效果見10.2節
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(); //渲染結束
device.Present(); //更新顯示區域，把後備緩存的圖形送到圖形卡的顯存中顯示
}
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); //牆壁
verts[0].Position = new Vector3(-2.0f, -2.0f, 2.0f); //頂點0位置
verts[0].Tu = 0.0f; //頂點0紋理座標Tu
verts[0].Tv = 1.0f;
verts[1].Position = new Vector3(-2.0f, 2.0f, 2.0f); //頂點1位置
verts[1].Tu = 0.0f; //頂點1紋理座標Tu
verts[1].Tv = 0.0f;
verts[2].Position = new Vector3(2.0f, 2.0f, 2.0f); //頂點2位置
verts[2].Tu = 1.0f; //頂點2紋理座標Tu
verts[2].Tv = 0.0f;
verts[3].Position = new Vector3(-2.0f, -2.0f, 2.0f); //頂點3位置
verts[3].Tu = 0.0f; //頂點3紋理座標Tu
verts[3].Tv = 1.0f;
verts[4].Position = new Vector3(2.0f, 2.0f, 2.0f); //頂點4位置
verts[4].Tu = 1.0f; //頂點4紋理座標Tu
verts[4].Tv = 0.0f;
verts[5].Position = new Vector3(2.0f, -2.0f, 2.0f); //頂點5位置
verts[5].Tu = 1.0f; //頂點5紋理座標Tu
verts[5].Tv = 1.0f;
vertexBuffer1.Unlock();
}
private void SetupMatrices() //修改Device的3個變換
{
device.Transform.World = Matrix.RotationY(0); //世界變換矩陣
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); //投影變換矩陣
}
private void Form1_Load(object sender, EventArgs e)
{
InitializeGraphics();
this.Show();
Render();
}
}
}
在程序運行時有時需要多個不同分辨率的同一張圖片，以適合大小不同的物體表面貼圖用，當物體離觀察者近的適合使用高質量的紋理，而物體離觀察者遠的時候使用低分辨率的紋理。這時就需要使用多級漸進紋理來控制渲染時紋理的質量，但是這樣做的代價是會吃掉更多的內存。