Please do not reply to this email- if you want to comment on the bug, go to the URL shown below and enter your comments there.
Changed by [EMAIL PROTECTED] http://bugzilla.ximian.com/show_bug.cgi?id=79254 --- shadow/79254 2006-09-02 14:38:37.000000000 -0400 +++ shadow/79254.tmp.31284 2006-09-02 14:38:37.000000000 -0400 @@ -0,0 +1,62 @@ +Bug#: 79254 +Product: Mono: Class Libraries +Version: unspecified +OS: +OS Details: 2.6.11-1.1369_FC4 #1 Thu Jun 2 22:55:56 EDT 2005 i686 i686 i386 GNU/Linux +Status: NEW +Resolution: +Severity: +Priority: Major +Component: Sys.Drawing. +AssignedTo: [EMAIL PROTECTED] +ReportedBy: [EMAIL PROTECTED] +QAContact: [EMAIL PROTECTED] +TargetMilestone: --- +URL: +Cc: +Summary: Matrix.Scale() causes unwanted x,y Translation. + +Please fill in this template when reporting a bug, unless you know what you +are doing. +Description of Problem: + +When using Matrix.Scale() it appears that an unwanted translation occurs as +a result. The amount of translation is apparently proportional to the +scale factors used in Matrix.Scale(sf, sf). + +Actual Results: +If Scale(100, 100) is used just before drawing a line with +DrawLine(0,0...), then the actual visible results are drawn at (128, 64...). + +Expected Results: +I would expect the start of the line (0,0) to be at (0,0) because scaline +0,0 would have no effect. + +How often does this happen? +Every time without fail. (Many millions of attempts) + +Additional Information: + +A test app that I wrote on Windows to check this actually performed +correctly on windows, but when that binary was run on my linux box with +mono (Compiler: gmcs, versions 1.1.14 and 1.1.17) this strange phenomena +was observed. + +I have managed to get around the problem by adding the following kludge-fix + in my own code... + +I insert this line BEFORE any of my program-specific scaling and +translating code: + +MyMatrix.Translate( -scalefactor, -(scalefactor / 2)); + +This seems to fix the problem. To me it feels like there is a bug in the +Matrix.Scale() implementation, just a hunch though. + +(I'm a seasoned graphics programmer so I know make sure I've reset all my +transformations each time I render from scratch.) + +I only noticed this bug because I'm writing a CAD package for Windows/Linux +and I need to make sure that everything is drawn as pixel perfect as possible. + +Hope this helps. _______________________________________________ mono-bugs maillist - [email protected] http://lists.ximian.com/mailman/listinfo/mono-bugs
