Hi all,
I had been been trying for the double buffering technique to draw
line on movement of mouse on pictureBox.The following is the piece of code:



private void pictureBox1_MouseMove(object sender,MouseEventArgs
e)

{

if(e.Button==MouseButtons.Left)

{



Bitmap backbuffer=new
Bitmap(pictureBox1.Width,pictureBox1.Height);

Graphics bckgphcs=Graphics.FromImage(backbuffer);



Graphics picgphcs=pictureBox1.CreateGraphics();



SolidBrush redbrush=new SolidBrush(Color.Red);

Pen redpen=new Pen(redbrush,2);



endpoint.X=e.X;endpoint.Y=e.Y;



bckgphcs.DrawImage(pictureBox1.Image,0,0);

bckgphcs.DrawLine(redpen,startpoint,endpoint);



picgphcs.DrawImage(backbuffer,0,0);



bckgphcs.Dispose();

picgphcs.Dispose();



backbuffer.Dispose();

redbrush.Dispose();redpen.Dispose();

}



It works well when I try for the first time.As I do it again and again,my
CPU resources shoot upto 100% and line drawing becomes slow.



Is there any way out????



regards

Rithesh

Firstly, if you are to do custom drawing, don't use a PictureBox -- use a
custom control. Secondly, do not dispose the back buffer every-time. If it
has not changed size you can reuse it.

Regards,
Frank Hileman

check out VG.net: http://www.vgdotnet.com
Animated vector graphics system
Integrated Visual Studio .NET graphics editor

"Rithesh Pai" <rithesh (AT) sninform (DOT) com> wrote

You're breaking all the rules here.

#1 Don't use GetGraphics to obtain a graphics object to draw onto.

#2 Don't draw in event handlers that are not meant for drawing.

#3 Don't create objects that use large amounts of memory in event handlers
that occur many times a second.

#4 Don't use PictureBox for anything other than displaying a static picture.



--
Bob Powell [MVP]
Visual C#, System.Drawing

Ramuseco Limited .NET consulting
http://www.ramuseco.com

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"Rithesh Pai" <rithesh (AT) sninform (DOT) com> wrote

If you are open to looking at alternatives to Picturebox
Take a look at our MetaDraw component ( www.Bennet-Tec.com)
With MetaDraw it's easy
Take a look at the following web page
www.btis.com/btproducts/MetaDraw/WebSamples/Drawing/md3_demo.htm
This shows MetaDraw in use for end-user drawing within a web browser
Of course the same thing can be done with MetaDraw in your EXE
application.
Note that you can View Source on this web page to see the underlying
code
and how easy this is.
With MetaDraw you just set an EditMode property to specify the result
of user mouse actions ( drawing lines, rectangles, other shapes,
selecting or moving shapes, etc) Lot's more. Just as important as
ease of use, MetaDraw will also allow you to capture the drawn shapes
as individual elements and then when you save and reload you can
continue to recognize and modify the shapes. You'll also get higher
quality printed output and smaller saved files.

I hope this is helpful to you.


* * Please include a copy of this message with your reply

Jeff Bennett
Jeff (AT) Bennet-Tec (DOT) Com

* Bennet-Tec Information Systems, Inc
* 50 Jericho Tpk, Jericho, NY 11753
* Phone 516 997 5596, Fax - 5597
* RELIABLE Components Make You Look Sharp!
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