Filling Figures with Brushes

You use brushes to fill in graphics figures. (See the previous topic and the discussion in the In Depth section of this chapter.) To illustrate, take a look at the FillGraphics example on the CD-ROM, which you can see at work in Figure 13.2. This example draws four ellipses and fills them in with the FillEllipse method using various brushes-LinearGradientBrush, HatchBrush, SolidBrush, and TextureBrush. To use these classes, you import the System.Drawing.Drawing2D namespace. Here's what this example looks like in code; note that the texture brush uses an image to fill a figure. In this case, I'm using the greenstone.bmp image that comes with Windows 2000:

Imports System.Drawing.Drawing2D
Public Class Form1
    Inherits System.Windows.Forms.Form

    'Windows Form Designer generated code

    Private Sub Form1_Paint(ByVal sender As Object, _
        ByVal e As System.Windows.Forms.PaintEventArgs) _
        Handles MyBase.Paint
        Dim g As Graphics
        Dim r As Rectangle
        g = Me.CreateGraphics()

        r = New Rectangle(20, 20, 60, 60)
        Dim lb As New LinearGradientBrush(_
           r, Color.Red, Color.Yellow, LinearGradientMode.Horizontal)
        g.FillEllipse(lb, r)

        r = New Rectangle(20, 100, 60, 60)
        Dim hb As New HatchBrush(HatchStyle.DarkDownwardDiagonal, _
            Color.LightBlue)
        g.FillEllipse(hb, r)

        r = New Rectangle(100, 20, 60, 60)
        Dim sb As New SolidBrush(Color.Coral)
        g.FillEllipse(sb, r)

        r = New Rectangle(100, 100, 60, 60)
        Dim tb As New TextureBrush(Bitmap.FromFile("greenstone.bmp"))
        g.FillEllipse(tb, r)
    End Sub
End Class

To use a Pen, you use the DrawXXX method of the Graphics class, and to fill the figure in using a brush, you use the FillXXX methods. For more on setting the colors of brushes, see "Specifying Drawing Colors," and to see how to use pre-defined brushes, see "Using the Pens and Brushes Classes," both in this chapter.