Matrix.Reset 方法

定义

命名空间:

System.Drawing.Drawing2D

程序集:

System.Drawing.Common.dll

包:

System.Drawing.Common v8.0.0

Source:

Matrix.cs

重置此 Matrix 得到单位矩阵的元素。

public:
 void Reset();

public void Reset ();

member this.Reset : unit -> unit

Public Sub Reset ()

示例

下面的代码示例旨在与 Windows 窗体 一起使用，它需要 PaintEventArgse事件Paint对象。 此代码执行以下操作：

• 创建缩放矩阵。

• 将矩阵元素Lists屏幕。

• 将矩阵重置为标识。

• 将元素Lists屏幕。

• 将矩阵在 x 轴上平移 50 磅，在 y 轴上平移 40 磅。

• 将转换矩阵的元素Lists到屏幕。

• 在 (蓝色矩形) 应用矩阵转换之前，绘制一个矩形。

• 将转换应用于矩形。

• 使用与上一个矩形相同的坐标，将转换的矩形绘制到屏幕 (红色矩形) 。

请注意，由于重置) ，红色矩形未 (缩放，而是在 x 轴和 y 轴中转换。

public:
   void ResetExample( PaintEventArgs^ e )
   {
      Pen^ myPen = gcnew Pen( Color::Blue,1.0f );
      Pen^ myPen2 = gcnew Pen( Color::Red,1.0f );

      // Create a matrix that scales by 5 in the x direction and
      // by 3 in the y direction.
      Matrix^ myMatrix = gcnew Matrix( 5.0f,0.0f,0.0f,3.0f,0.0f,0.0f );

      // List the matrix elements to the screen.
      ListMatrixElements( e, myMatrix, "Beginning Matrix", 6, 20 );

      // Reset the matrix to identity.
      myMatrix->Reset();

      // Again list the matrix elements to the screen.
      ListMatrixElements2( e, myMatrix, "Matrix After Reset", 6, 40 );

      // Translate the matrix by 50 points in the x-axis and 40 points
      // in the y-axis.
      myMatrix->Translate( 50.0f, 40.0f );

      // List the matrix elements to the screen.
      ListMatrixElements1( e, myMatrix, "Matrix After Translation", 6, 60 );

      // Draw a rectangle to the screen.
      e->Graphics->DrawRectangle( myPen, 0, 0, 100, 100 );

      // Apply the matrix transform to the Graphics.
      e->Graphics->Transform = myMatrix;

      // Draw another rectangle to the screen that has the transform
      // applied.
      e->Graphics->DrawRectangle( myPen2, 0, 0, 100, 100 );
   }

   //-------------------------------------------------------
   // This function is a helper function to
   // list the contents of a matrix.
   //-------------------------------------------------------
   void ListMatrixElements2( PaintEventArgs^ e, Matrix^ matrix, String^ matrixName, int numElements, int y )
   {
      // Set up variables for drawing the array
      // of points to the screen.
      int i;
      float x = 20,X = 200;
      System::Drawing::Font^ myFont = gcnew System::Drawing::Font( "Arial",8 );
      SolidBrush^ myBrush = gcnew SolidBrush( Color::Black );

      // Draw the matrix name to the screen.
      e->Graphics->DrawString( String::Concat( matrixName, ":  " ), myFont, myBrush, (float)x, (float)y );

      // Draw the set of path points and types to the screen.
      for ( i = 0; i < numElements; i++ )
      {
         e->Graphics->DrawString( String::Concat( matrix->Elements[ i ], ", " ), myFont, myBrush, (float)X, (float)y );
         X += 30;
      }
   }

public void ResetExample(PaintEventArgs e)
{
    Pen myPen = new Pen(Color.Blue, 1);
    Pen myPen2 = new Pen(Color.Red, 1);
             
    // Create a matrix that scales by 5 in the x direction and
    // by 3 in the y direction.
    Matrix myMatrix = new Matrix(
        5.0f, 0.0f, 0.0f, 3.0f, 0.0f, 0.0f); 
             
    // List the matrix elements to the screen.
    ListMatrixElements(e, myMatrix, "Beginning Matrix", 6, 20);
             
    // Reset the matrix to identity.
    myMatrix.Reset();
             
    // Again list the matrix elements to the screen.
    ListMatrixElements2(e, myMatrix, "Matrix After Reset", 6, 40);
             
    // Translate the matrix by 50 points in the x-axis and 40 points
    // in the y-axis.
    myMatrix.Translate(50.0f, 40.0f); 
  
    // List the matrix elements to the screen.
    ListMatrixElements1(e, myMatrix, "Matrix After Translation", 6, 60);
             
    // Draw a rectangle to the screen.
    e.Graphics.DrawRectangle(myPen, 0, 0, 100, 100);
             
    // Apply the matrix transform to the Graphics.
    e.Graphics.Transform = myMatrix;
             
    // Draw another rectangle to the screen that has the transform
    // applied.
    e.Graphics.DrawRectangle(myPen2, 0, 0, 100, 100);
}
             
//-------------------------------------------------------
// This function is a helper function to
// list the contents of a matrix.
//-------------------------------------------------------
public void ListMatrixElements2(
    PaintEventArgs e,
    Matrix matrix,
    string matrixName,
    int numElements,
    int y)
{
             
    // Set up variables for drawing the array
    // of points to the screen.
    int i;
    float x = 20, X = 200;
    Font myFont = new Font("Arial", 8);
    SolidBrush myBrush = new SolidBrush(Color.Black);
             
    // Draw the matrix name to the screen.
    e.Graphics.DrawString(
        matrixName + ":  ",
        myFont,
        myBrush,
        x,
        y);
             
    // Draw the set of path points and types to the screen.
    for(i=0; i < numElements; i++)
    {
        e.Graphics.DrawString(
            matrix.Elements[i].ToString() + ", ",
            myFont,
            myBrush,
            X,
            y);
        X += 30;
    }
}

Public Sub ResetExample(ByVal e As PaintEventArgs)
    Dim myPen As New Pen(Color.Blue, 1)
    Dim myPen2 As New Pen(Color.Red, 1)
    Dim myMatrix As New Matrix(5.0F, 0.0F, 0.0F, 3.0F, 0.0F, 0.0F)

    ListMatrixElementsHelper2(e, myMatrix, "Beginning Matrix", 6, 20)
    myMatrix.Reset()
    ListMatrixElementsHelper(e, myMatrix, "Matrix After Reset", 6, 40)

    ' Translate.
    myMatrix.Translate(50.0F, 40.0F)

    ListMatrixElementsHelper(e, myMatrix, "Matrix After Translation", _
        6, 60)
    e.Graphics.DrawRectangle(myPen, 0, 0, 100, 100)
    e.Graphics.Transform = myMatrix
    e.Graphics.DrawRectangle(myPen2, 0, 0, 100, 100)
End Sub

' A helper function to list the contents of a matrix.
Public Sub ListMatrixElementsHelper2(ByVal e As PaintEventArgs, _
ByVal matrix As Matrix, ByVal matrixName As String, ByVal numElements As Integer, _
ByVal y As Integer)

    ' Set up variables for drawing the array
    ' of points to the screen.
    Dim i As Integer
    Dim x As Single = 20
    Dim j As Single = 200
    Dim myFont As New Font("Arial", 8)
    Dim myBrush As New SolidBrush(Color.Black)

    ' Draw the matrix name to the screen.
    e.Graphics.DrawString(matrixName + ":  ", myFont, myBrush, x, y)

    ' Draw the set of path points and types to the screen.
    For i = 0 To numElements - 1
        e.Graphics.DrawString(matrix.Elements(i).ToString() + ", ", _
        myFont, myBrush, j, y)
        j += 30
    Next i
End Sub

注解

标识矩阵main对角线上的元素为 1。 标识矩阵的所有其他元素均为 0。