... perhaps there's a way to set the transforming object's origin to it's center some how? i could work with that...
On Wed, Jun 17, 2009 at 2:37 PM, Chunk 1978<chunk1...@gmail.com> wrote: > still having issues. i've changed the order of transforms: > > -=-=-=- > CGAffineTransform transform = > CGAffineTransformMakeTranslation(centerPoint.x, centerPoint.y); > transform = CGAffineTransformScale(transform, 2, 2); > transform = CGAffineTransformRotate(transform, > kDegreesToRadian(90)); > square.transform = transform; > -=-=-=- > > although this code supposedly scales the Square before translating it > to it's new origin, it maintains the Squares original origin based on > it's original size. so eventhough the Square is now twice as big, it > is translated to the center of the screen minus it's new scale. i can > remedy it by adding this: > > -=-=-=- > CGRect squareFrame = [square frame]; > CGAffineTransform transform = > CGAffineTransformMakeTranslation(centerPoint.x + > squareFrame.size.width / 2, centerPoint.y + squareFrame.size.height / > 2); > -=-=-=- > > but that seems like a hack... > > any ideas? > > > On Wed, Jun 17, 2009 at 12:31 PM, Kyle Sluder<kyle.slu...@gmail.com> wrote: >> On Wed, Jun 17, 2009 at 9:14 AM, Gordon Apple<g...@ed4u.com> wrote: >>> IMHO, matrix operations are one of the most confusing and cumbersome >>> aspects of Cocoa. Every time I use them, I end up trying most combinations >>> until I get the desired result. C++ doesn't have this problem. You can >>> simply write the matrix equations and be done with it. I love Objective C, >>> but operator overloading (and ctors/dtors) are the things I miss most. >>> Multiple inheritance -- not so much. >> >> This isn't a C++/ObjC issue. Whatever matrix library you were using >> under C++ happened to define matrix multiplication in such a way that >> it performed the operations in reverse order. XNA, on the other hand, >> follows the same pattern as Cocoa, even though it's written in C# and >> therefore has operator overloading. >> >> The AppKit team could very easily have implemented NSAffineTransform >> to transparently define a stack. But they didn't. Neither did the >> OpenGL people, or the XNA people. But it's not a language issue. >> >> --Kyle Sluder >> _______________________________________________ >> >> Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) >> >> Please do not post admin requests or moderator comments to the list. >> Contact the moderators at cocoa-dev-admins(at)lists.apple.com >> >> Help/Unsubscribe/Update your Subscription: >> http://lists.apple.com/mailman/options/cocoa-dev/chunk1978%40gmail.com >> >> This email sent to chunk1...@gmail.com >> > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
