Exposing Your True Artist

Okay, we've covered most of the basic GDI+ features used to draw images. It's all now just a matter of issuing the drawing commands for shapes, images, and text on a graphics surface. Most of the time, you'll stick with the methods included on the Graphics object, all 12 bazillion of them. Perhaps I over-counted, but there are quite a few. Here's just a sampling.

  • Clear method. Clear the background with a specific color.

  • CopyFromScreen method. If the "Prnt Scrn" button on your keyboard falls off, this is the method for you.

  • DrawArc method. Draw a portion of an arc along the edge of an ellipse. Zero degrees starts at three o'clock. Positive arc sweep values move in a clockwise direction; use negative sweep values to move counterclockwise.

  • DrawBezier and DrawBeziers methods. Draw one Bezier spline, or a continuing curve made up of multiple connected splines.

  • DrawCurve, DrawClosedCurve, and FillClosedCurve methods. Draw "cardinal" curves, with an optional brush fill.

  • DrawEllipse and FillEllipse methods. Draw an ellipse or a circle (which is a variation of an ellipse).

  • DrawIcon, DrawIconUnstretched, DrawImage, DrawImageUnscaled, and DrawImageUnscaledAndClipped methods. Different ways of drawing images and icons.

  • DrawLine and DrawLines methods. Draw one or more lines with lots of options for making the lines snazzy.

  • DrawPath and FillPath methods. I'll discuss "graphic paths" a little later.

  • DrawPie and FillPie methods. Draw a pie-slice border along the edge of an ellipse.

  • DrawPolygon and FillPolygon methods. Draw a regular or irregular geometric shape based on a set of points.

  • DrawRectangle, DrawRectangles, FillRectangle, and FillRectangles methods. Draw squares and rectangles.

  • DrawString method. We used this before to output text to the canvas.

  • FillRegion method. I'll discuss regions later in the chapter.

Here's some sample drawing code.

' ----- Line from (10, 10) to (40, 40). e.Graphics.DrawLine(Pens.Black, 10, 10, 40, 40) ' ----- 90degree clockwise arc for 40-pixel diameter circle. e.Graphics.DrawArc(Pens.Black, 50, 10, 40, 40, 0, -90) ' ----- Filled 40x40 rectangle with a dashed line. e.Graphics.FillRectangle(Brushes.Honeydew, 120, 10, 40, 40) Dim dashedPen As New Pen(Color.Black, 2) dashedPen.DashStyle = Drawing2D.DashStyle.Dash e.Graphics.DrawRectangle(dashedPen, 120, 10, 40, 40) dashedPen.Dispose() ' ----- A slice of elliptical pie. e.Graphics.FillPie(Brushes.BurlyWood, 180, 10, 80, 40, _    180, 120) 

And so on. You get the idea. Figure 17-9 shows the output for this code.

Figure 17-9. Some simple drawings

Start-to-Finish Visual Basic 2005. Learn Visual Basic 2005 as You Design and Develop a Complete Application
Start-to-Finish Visual Basic 2005: Learn Visual Basic 2005 as You Design and Develop a Complete Application
ISBN: 0321398009
EAN: 2147483647
Year: 2006
Pages: 247
Authors: Tim Patrick

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net