Lesson 26: Mastering Graphics Programming in VB2022

' Create graphics object for the form
Dim g As Graphics = Me.CreateGraphics()

' Create graphics for a PictureBox
Dim pbGraphics As Graphics = PictureBox1.CreateGraphics()

' Create graphics from a Bitmap (for persistent drawings)
Dim bmp As New Bitmap(400, 300)
Dim memGraphics As Graphics = Graphics.FromImage(bmp)

' Create a blue pen with 3px width
Dim bluePen As New Pen(Color.Blue, 3)

' Create a red solid brush
Dim redBrush As New SolidBrush(Color.Red)

' Create a gradient brush
Dim gradBrush As New LinearGradientBrush(
    New Point(0, 0),
    New Point(100, 100),
    Color.Yellow,
    Color.Orange)

Private Sub BtnDrawLine_Click(sender As Object, e As EventArgs) Handles BtnDrawLine.Click
    ' Create graphics object
    Dim g As Graphics = Me.CreateGraphics()
    
    ' Create a pen
    Dim myPen As New Pen(Brushes.DarkMagenta, 10)
    
    ' Draw a line from (60,80) to (220,50)
    g.DrawLine(myPen, 60, 80, 220, 50)
    
    ' Dispose of resources
    myPen.Dispose()
    g.Dispose()
End Sub

Private Sub BtnDrawRectangle_Click(sender As Object, e As EventArgs) Handles BtnDrawRectangle.Click
    Dim g As Graphics = Me.CreateGraphics()
    
    ' Create a blue pen for border
    Dim borderPen As New Pen(Color.Blue, 3)
    
    ' Create a red brush for fill
    Dim fillBrush As New SolidBrush(Color.Red)
    
    ' Define rectangle position and size
    Dim rect As New Rectangle(50, 50, 200, 150)
    
    ' Draw the rectangle border
    g.DrawRectangle(borderPen, rect)
    
    ' Fill the rectangle
    g.FillRectangle(fillBrush, rect)
    
    ' Clean up resources
    borderPen.Dispose()
    fillBrush.Dispose()
    g.Dispose()
End Sub

Private Sub BtnDrawCircle_Click(sender As Object, e As EventArgs) Handles BtnDrawCircle.Click
    Dim g As Graphics = Me.CreateGraphics()
    
    ' Create a green pen
    Dim circlePen As New Pen(Color.Green, 4)
    
    ' Create a yellow brush
    Dim circleBrush As New SolidBrush(Color.Yellow)
    
    ' Define circle position and size
    Dim circleRect As New Rectangle(100, 100, 150, 150)
    
    ' Draw the circle
    g.DrawEllipse(circlePen, circleRect)
    g.FillEllipse(circleBrush, circleRect)
    
    ' Draw an ellipse
    Dim ellipseRect As New Rectangle(300, 150, 200, 100)
    g.DrawEllipse(Pens.Blue, ellipseRect)
    g.FillEllipse(Brushes.Cyan, ellipseRect)
    
    ' Clean up resources
    circlePen.Dispose()
    circleBrush.Dispose()
    g.Dispose()
End Sub

Private Sub BtnDrawHouse_Click(sender As Object, e As EventArgs) Handles BtnDrawHouse.Click
    Dim g As Graphics = Me.CreateGraphics()
    
    ' Create pens and brushes
    Dim wallPen As New Pen(Color.Black, 2)
    Dim wallBrush As New SolidBrush(Color.LightBlue)
    Dim roofPen As New Pen(Color.Brown, 3)
    Dim roofBrush As New SolidBrush(Color.SaddleBrown)
    Dim doorBrush As New SolidBrush(Color.Brown)
    Dim windowBrush As New SolidBrush(Color.White)
    
    ' Draw house body (rectangle)
    Dim houseRect As New Rectangle(100, 150, 200, 150)
    g.FillRectangle(wallBrush, houseRect)
    g.DrawRectangle(wallPen, houseRect)
    
    ' Draw roof (triangle)
    Dim roofPoints() As Point = {
        New Point(90, 150),  ' Left point
        New Point(200, 80),  ' Top center
        New Point(310, 150)  ' Right point
    }
    g.FillPolygon(roofBrush, roofPoints)
    g.DrawPolygon(roofPen, roofPoints)
    
    ' Draw door
    Dim doorRect As New Rectangle(180, 220, 40, 80)
    g.FillRectangle(doorBrush, doorRect)
    g.DrawRectangle(wallPen, doorRect)
    
    ' Draw windows
    Dim leftWindow As New Rectangle(130, 180, 30, 30)
    Dim rightWindow As New Rectangle(240, 180, 30, 30)
    
    g.FillRectangle(windowBrush, leftWindow)
    g.DrawRectangle(wallPen, leftWindow)
    
    g.FillRectangle(windowBrush, rightWindow)
    g.DrawRectangle(wallPen, rightWindow)
    
    ' Draw window panes
    g.DrawLine(wallPen, 145, 180, 145, 210) ' Vertical
    g.DrawLine(wallPen, 130, 195, 160, 195) ' Horizontal
    
    g.DrawLine(wallPen, 255, 180, 255, 210) ' Vertical
    g.DrawLine(wallPen, 240, 195, 270, 195) ' Horizontal
    
    ' Clean up resources
    wallPen.Dispose()
    wallBrush.Dispose()
    roofPen.Dispose()
    roofBrush.Dispose()
    doorBrush.Dispose()
    windowBrush.Dispose()
    g.Dispose()
End Sub