View Issue Details
|ID||Project||Category||View Status||Date Submitted||Last Update|
|0010332||Lazarus||-||public||2007-12-03 00:39||2008-04-24 10:08|
|Reporter||Martin Friebe||Assigned To||Vincent Snijders|
|Status||closed||Resolution||no change required|
|Summary||0010332: DrawGrid.Canvas.Pixel problem with x coords 256-511 (bit 8 set) (Windows)|
|Description||Accessing the canvas.Pixel property of a DrawGrid shows a strange behaviour.|
You can Draw Lines, or use any function to draw anywhere on the Canvas. BUT if you use the Pixel[X,Y]:=TColor property you will experience a strange behaviour.
Any X coordinate with bit8 set (256-511, 768=1023, ...) will be ignored.
Using a TPaintbox, or TImage will work fine. Using Functions such as Rectangle or Line will also work (even on the TDrawGrid).
|Additional Information||To Reproduce, set up a new Application with a TButton and a TDrawGrid on a TForm|
Ensure the Drawgrid is at least 600 pixel width.
add the following code to the ButtonClick, and run it:
procedure TForm1.Button1Click(Sender: TObject);
var i : integer;
for i := 1 to 600 do begin
You will be noticing a 256 Pixel Gap in the Red line
|Tags||No tags attached.|
|Fixed in Revision|
I cannot reproduce this issue. Can you create a example applictaion and a screenshot?
What windows version do you use?
What color depth do you use?
canvas.rar (389,051 bytes)
I am running Windows Vista (Home Prem) 32Bit Version. Running on Intel Core2Duo.
Color deep is 32 bit.
The application is compiled with the settings for win32.
I get the issue using Lazarus 0.9.24 with fpc 2.2.0 (from sourceforge).
I also get it with the snapshot from 23 Nov (0.9.25 with fpc 2.2.1).
The ZIP contains Source, Exe, and a JPEG.
In the jpeg you can see a thin red line at the top of the grid. It should be continuous.
It is also notice-able that the issue exists only for the X-coordinate. If I draw the line along the Y-axis, it works.
This seems to be Windows VISTA only.
I tried the same exe (the exe that was compiled under Vista (and is in the attachment)), running this exe under Windows-XP, produces correct results.
Running it under Vista, produces the error.
This may be a bug in Vista, rather than Lazarus.
I have just created the same project with Turbo Delphi. (created a new project from scratch). Turbo Delphi has the same problem.
Another Vista user checked and didn't report this problem. Maybe it has something to do with your specific Vista setup.
I will close this issue for Lazarus.
|2007-12-03 00:39||Martin Friebe||New Issue|
|2007-12-03 00:39||Martin Friebe||Widgetset||=> Win32|
|2007-12-03 03:28||Vincent Snijders||LazTarget||=> 1.0|
|2007-12-03 03:28||Vincent Snijders||Status||new => acknowledged|
|2007-12-03 17:51||Vincent Snijders||Note Added: 0016563|
|2007-12-03 17:51||Vincent Snijders||Status||acknowledged => feedback|
|2007-12-04 03:22||Martin Friebe||File Added: canvas.rar|
|2007-12-04 03:31||Martin Friebe||Note Added: 0016572|
|2007-12-04 12:52||Martin Friebe||Note Added: 0016586|
|2007-12-04 21:48||Martin Friebe||Note Added: 0016594|
|2007-12-05 09:00||Vincent Snijders||Status||feedback => resolved|
|2007-12-05 09:00||Vincent Snijders||Resolution||open => no change required|
|2007-12-05 09:00||Vincent Snijders||Assigned To||=> Vincent Snijders|
|2007-12-05 09:00||Vincent Snijders||Note Added: 0016598|
|2008-03-29 12:18||Marc Weustink||Status||resolved => closed|
|2008-04-24 10:08||Vincent Snijders||Target Version||=> 1.0.0|
|2010-03-12 14:52||Vincent Snijders||Relationship added||related to 0015822|