Ken, I played around with this some more and I can get satisfactory results by setting the image interpolation to NSImageInterpolationHigh, along with making sure the dest size lies on integers. So it looks like I was being bit by the default resampling method.
Thanks! - Dave.S On Thu, Aug 21, 2008 at 2:34 PM, David Springer <[EMAIL PROTECTED]> wrote: > Hi Ken, > > I can build a test app - give me a couple hours to put it together. > > As for antialiasing, I thought that might be the problem, but I set > the image interpolation on the graphics context to > NSImageInterpolationNone and get the same results. > > I am on Leopard 10.5.4 (this all has to work on Tiger, as well though). > > Thanks > - Dave.S > > > On Thu, Aug 21, 2008 at 2:26 PM, Ken Ferry <[EMAIL PROTECTED]> wrote: >> Hi David, >> >> Could you post a complete test app? There's nothing in what you've >> posted that looks problematic[1]. Also, what OS are you working on? >> >> -Ken >> >> [1]: well, except maybe that you're likely to see antialiasing on the edges. >> Your problem looks more severe than antialiasing, though. >> >> On Thu, Aug 21, 2008 at 12:47 PM, David Springer <[EMAIL PROTECTED]> wrote: >>> Folks, >>> >>> For some reason, I am not able to figure this out. I want to draw a >>> scaled NSImage, but the edges of the image are not drawn, it seems >>> like the resizing actually clips the image. >>> >>> I have an NSBitmapImageRep created from some data. I then create the >>> NSImage like this: >>> >>> NSImage *image = [[NSImage alloc] initWithSize:NSMakeSize([myBitmap >>> pixelsWide], [myBitmap pixelsHigh]); >>> [image addRepresentation:myBitmap]; >>> [image setScalesWhenResized:YES]; >>> >>> // Figure out the new image size so that it is proportionally scaled >>> by |scaleFactor|. >>> NSSize scaledSize = ProportionallyScale([image size], scaleFactor); >>> [image drawInRect:NSMakeRect((kTileImageSize - scaledSize.width) * 0.5, >>> (kTileImageSize - scaledSize.height) * >>> 0.5, >>> scaledSize.width, >>> scaledSize.height) >>> fromRect:NSZeroRect >>> operation:NSCompositeSourceOver >>> fraction:1.0]; >>> >>> This sometimes works (that is, the entire original image is visible). >>> But more often than not, the edges of the original image are not >>> drawn. See the screen shots for a picture of what I get. >>> >>> What am I doing wrong here? I have scoured the archives, I have tried >>> things like making sure scaledSize has integer values, I have even >>> done crazy things like add one to the height just to see what would >>> happen. Note that if I write out the TIFFRepresentation of |image| >>> (both before and after) the entire image gets into the file (that is, >>> the edges are not clipped). >>> >>> In the attached picture, the top tile is correct (you see all the >>> black edges), the bottom two tiles are incorrect (not all the black >>> edges are visible). >>> >>> Help? >>> Thanks! >>> - Dave.S >>> >>> _______________________________________________ >>> >>> 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/kenferry%40gmail.com >>> >>> This email sent to [EMAIL PROTECTED] >>> >> > _______________________________________________ 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 [EMAIL PROTECTED]
