Codejock Developer Community : TrackControl overflow problem http://forum.codejock.com/ Copyright (c) 2006-2013 Web Wiz Forums - All Rights Reserved. Tue, 19 May 2026 05:24:17 +0000 Wed, 23 Jun 2010 05:02:22 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 12.04 360 forum.codejock.com/RSS_post_feed.asp?TID=16855 <![CDATA[Codejock Developer Community]]> http://forum.codejock.com/forum_images/codejock-logo.gif http://forum.codejock.com/ <![CDATA[TrackControl overflow problem : Thanks, replaced also. ]]> http://forum.codejock.com/forum_posts.asp?TID=16855&PID=59077&title=trackcontrol-overflow-problem#59077 Author: Oleg
Subject: 16855
Posted: 23 June 2010 at 5:02am

Thanks, replaced also.]]> Wed, 23 Jun 2010 05:02:22 +0000 http://forum.codejock.com/forum_posts.asp?TID=16855&PID=59077&title=trackcontrol-overflow-problem#59077 <![CDATA[TrackControl overflow problem : No problem. I also found a couple...]]> http://forum.codejock.com/forum_posts.asp?TID=16855&PID=59063&title=trackcontrol-overflow-problem#59063 Author: Aaron Koolen
Subject: 16855
Posted: 21 June 2010 at 5:49pm

No problem. I also found a couple of other places where the same thing occurs.

XTPrackPaintManager::DrawTrackHeader, around line 305.
XTPTrackHeader::OnLButtonDown, around line 418.

Both of those perform out of range multiplications.

Cheers
Aaron

]]> Mon, 21 Jun 2010 17:49:35 +0000 http://forum.codejock.com/forum_posts.asp?TID=16855&PID=59063&title=trackcontrol-overflow-problem#59063 <![CDATA[TrackControl overflow problem : Thanks, replaced to int fromPosition...]]> http://forum.codejock.com/forum_posts.asp?TID=16855&PID=59050&title=trackcontrol-overflow-problem#59050 Author: Oleg
Subject: 16855
Posted: 21 June 2010 at 9:24am

Thanks, replaced to


     int fromPosition = MulDiv(m_ptStartDrag.x, (pControl->GetTimeLineMax() - pControl->GetTimeLineMin()), rcSliderArea.Width());
     int toPosition = MulDiv(pt.x, (pControl->GetTimeLineMax() - pControl->GetTimeLineMin()), rcSliderArea.Width());
]]> Mon, 21 Jun 2010 09:24:01 +0000 http://forum.codejock.com/forum_posts.asp?TID=16855&PID=59050&title=trackcontrol-overflow-problem#59050 <![CDATA[TrackControl overflow problem : Hi there. I was getting strange...]]> http://forum.codejock.com/forum_posts.asp?TID=16855&PID=59037&title=trackcontrol-overflow-problem#59037 Author: Aaron Koolen
Subject: 16855
Posted: 20 June 2010 at 11:17pm

Hi there.
I was getting strange behaviour with my TrackControl where the slider would jump to the end of my time line range when I reached a certain position. I tracked the issue down to an overflow in the CXTPTrackControlHeader OnMoveSlider (~line 180) method. 



int fromPosition = m_ptStartDrag.x * (pControl->GetTimeLineMax() - pControl->GetTimeLineMin()) / rcSliderArea.Width();

int toPosition = pt.x * (pControl->GetTimeLineMax() - pControl->GetTimeLineMin()) / rcSliderArea.Width();

int delta = toPosition - fromPosition;


With large timelines, as I had, the initial multiplication overflowed into negative. The fromPosition and toPosition can actually be removed and the delta performed before the multiplication and division. Even better would be to divide first, as I don't think the difference in rounding would matter. I have made the change in my code and all is working well.

As an aside to this, I would suggest that CXTPTrackControl handled unsigned.

Aaron

]]> Sun, 20 Jun 2010 23:17:56 +0000 http://forum.codejock.com/forum_posts.asp?TID=16855&PID=59037&title=trackcontrol-overflow-problem#59037