问个简单问题

123工艺品 2011-07-02 05:42:49





    Private Sub 光照效果ToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles 光照效果ToolStripMenuItem.Click

        '以光照效果显示图像,若按原设计则图片尺寸过大

        'Dim MyGraphics As Graphics = Me.PictureBox1.CreateGraphics()

        'MyGraphics.Clear(Color.White)

        'Dim MyBmp As New Bitmap(Me.PictureBox1.Image,Me.PictureBox1.Width, Me.PictureBox1.Height)

        'Dim MyWidth As Integer = MyBmp.Width

        'Dim MyHeight As Integer = MyBmp.Height

        Try

            Dim MyWidth As Integer = PictureBox1.Image.Width

            Dim MyHeight As Integer = PictureBox1.Image.Height

            Dim MyBmp As New Bitmap(Me.PictureBox1.Image, MyWidth, MyHeight)

            Dim MyImage As Bitmap = MyBmp.Clone(New RectangleF(0, 0, _

                MyWidth, MyHeight), System.Drawing.Imaging.PixelFormat.DontCare)

            'MyCenter图片中心点，发亮此值会让强光中心发生偏移

            Dim MyCenter As New Point(MyWidth / 2, MyHeight / 2)

            'Radius强光照射面的半径，即”光晕”

            Dim Radius As Integer = Math.Min(MyWidth / 2, MyHeight / 2)

            For i As Integer = MyWidth - 1 To 1 Step -1

                For j As Integer = MyHeight - 1 To 1 Step -1

                    Dim MyLength As Single = CType(Math.Sqrt(Math.Pow((i - _

                        MyCenter.X), 2) + Math.Pow((j - MyCenter.Y), 2)), Single)

                    '如果像素位于”光晕”之内

                    If (MyLength < Radius) Then

                        Dim MyColor As Color = MyImage.GetPixel(i, j)

                        Dim r, g, b As Integer

                        '220亮度增加常量，该值越大，光亮度越强

                        Dim MyPixel As Integer = 220.0F * (1.0F - MyLength / Radius)

                        r = MyColor.R + CType(MyPixel, Integer)

                        r = Math.Max(0, Math.Min(r, 255))

                        g = MyColor.G + CType(MyPixel, Integer)

                        g = Math.Max(0, Math.Min(g, 255))

                        b = MyColor.B + CType(MyPixel, Integer)

                        b = Math.Max(0, Math.Min(b, 255))

                        '将增亮后的像素值回写到位图

                        Dim MyNewColor As Color = Color.FromArgb(255, r, g, b)

                        MyImage.SetPixel(i, j, MyNewColor)

                    End If

                Next

                ' MyGraphics.DrawImage(MyImage, New Rectangle(0, 0, MyWidth, MyHeight))

            Next

            Me.PictureBox1.Image = MyImage

        Catch ex As Exception

            MessageBox.Show(ex.Message, "信息提示", _

                        MessageBoxButtons.OK, MessageBoxIcon.Information)

        End Try

    End Sub