摄像机矩阵变换

[code]     [code]public partial class MainForm : Form

{

public MainForm()

    {

InitializeComponent();

this.InitialDX();

}

private Device device;

private Vector3 camPosition = new Vector3(0, 30, -50);

private Vector3 camTarget = new Vector3(0, 0, 0);

private Vector3 camUp = new Vector3(0, 1, 0);

private float angle = 0.01f;

private void InitialDX()

    {

PresentParameters presentParams = new PresentParameters();

presentParams.Windowed = true;

presentParams.SwapEffect = SwapEffect.Discard;

device = new Device(

0,

DeviceType.Hardware,

this,

CreateFlags.SoftwareVertexProcessing,

presentParams);

device.RenderState.Lighting = false;

device.RenderState.CullMode = Cull.None;

device.Transform.View = Matrix.LookAtLH(

camPosition,

camTarget,

camUp);

device.Transform.Projection = Matrix.PerspectiveFovLH(

(float)Math.PI / 4,

this.Width / this.Height,

10,

500);

Texture texture = Texture.FromBitmap(

device,

(Bitmap)Image.FromFile("w.png"),

Usage.None,

Pool.Managed);

device.SetTexture(0, texture);

}

protected override void OnPaint(PaintEventArgs e)

    {

base.OnPaint(e);

this.DrawDX();

}

private void DrawDX()

    {

device.Clear(ClearFlags.Target, Color.Teal, 1f, 0);

device.BeginScene();

this.DrawMyGraphics();

device.EndScene();

device.Present();

}

private void DrawMyGraphics()

    {

CustomVertex.PositionTextured[] vertexs = new CustomVertex.PositionTextured[4];

vertexs[0].Position = new Vector3(10f, 0, 10f);

vertexs[1].Position = new Vector3(10f, 0, -10f);

vertexs[2].Position = new Vector3(-10f, 0, -10f);

vertexs[3].Position = new Vector3(-10f, 0, 10f);

vertexs[0].Tu = 1f;

vertexs[0].Tv = 0f;

vertexs[1].Tu = 1f;

vertexs[1].Tv = 1f;

vertexs[2].Tu = 0f;

vertexs[2].Tv = 1f;

vertexs[3].Tu = 0f;

vertexs[3].Tv = 0f;

device.VertexFormat = CustomVertex.PositionTextured.Format;

device.DrawUserPrimitives(PrimitiveType.TriangleFan,

2,

vertexs);

}

protected override void OnKeyDown(KeyEventArgs e)

    {

base.OnKeyDown(e);

Vector4 tempV;

switch (e.KeyCode)

 {

case Keys.Add: //放大

  {

camPosition.Subtract(camTarget);

camPosition.Scale(0.95f);

camPosition.Add(camTarget);

  }

break;

case Keys.Subtract: //缩小

  {

camPosition.Subtract(camTarget);

camPosition.Scale(1.05f);

camPosition.Add(camTarget);

  }

break;

case Keys.Up: //摄像机绕X轴顺时针旋转（目标逆时针旋转）

  {

camPosition.Subtract(camTarget);

tempV = Vector3.Transform(

            camPosition,

Matrix.RotationQuaternion(

Quaternion.RotationAxis(new Vector3(

device.Transform.View.M11,

device.Transform.View.M21,

device.Transform.View.M31),

angle)));

camPosition.X = tempV.X + camTarget.X;

camPosition.Y = tempV.Y + camTarget.Y;

camPosition.Z = tempV.Z + camTarget.Z;

  }

break;

case Keys.Down: //摄像机绕X轴逆时针旋转

  {

camPosition.Subtract(camTarget);

tempV = Vector3.Transform(

            camPosition,

Matrix.RotationQuaternion(

Quaternion.RotationAxis(new Vector3(

device.Transform.View.M11,

device.Transform.View.M21,

device.Transform.View.M31),

-angle)));

camPosition.X = tempV.X + camTarget.X;

camPosition.Y = tempV.Y + camTarget.Y;

camPosition.Z = tempV.Z + camTarget.Z;

  }

break;

case Keys.Left: //摄像机绕Y轴顺时针旋转（目标逆时针旋转）

  {

camPosition.Subtract(camTarget);

tempV = Vector3.Transform(

            camPosition,

Matrix.RotationQuaternion(Quaternion.RotationAxis(

new Vector3(device.Transform.View.M12,

device.Transform.View.M22,

device.Transform.View.M32),

angle)));

camPosition.X = tempV.X + camTarget.X;

camPosition.Y = tempV.Y + camTarget.Y;

camPosition.Z = tempV.Z + camTarget.Z;

  }

break;

case Keys.Right: //摄像机绕Y轴逆时针旋转

  {

camPosition.Subtract(camTarget);

tempV = Vector3.Transform(

            camPosition,

Matrix.RotationQuaternion(Quaternion.RotationAxis(

new Vector3(device.Transform.View.M12,

device.Transform.View.M22,

device.Transform.View.M32),

-angle)));

camPosition.X = tempV.X + camTarget.X;

camPosition.Y = tempV.Y + camTarget.Y;

camPosition.Z = tempV.Z + camTarget.Z;

  }

break;

case Keys.S:  //左平移

  {

camPosition.Subtract(camTarget);

camTarget.X -= 1f;

camPosition.Add(camTarget);

  }

break;

case Keys.F: //右平移

  {

camPosition.Subtract(camTarget);

camTarget.X += 1f;

camPosition.Add(camTarget);

  }

break;

 }

device.Transform.View = Matrix.LookAtLH(

camPosition,

camTarget,

camUp);

this.Invalidate();

}

}