> On Aug 24, 2016, at 1:23 AM, Jeff Szuhay <j...@szuhay.org> wrote: > > I’m using a bunch of layers to draw images to, compose them, and then draw > into a viewRect > with > > CGContextDrawLayerInRect( viewContext, viewRect, myLayer); > > Of course, I’m trying to pick the most reasonable size for my layers. I > currently use 1024x1024 > but could easily make them 512x512 or 768x768. > > So my question is, “Is is more efficient to draw the layer into a smaller > viewRect (down-sample) > or into a larger ViewRect (up-sample)?” > > Or does it even matter?
It depends on if quality or performance matters more. Downsampling is generally more expensive because you have to deal with more data and so you become more easily bandwidth limited, but at the same time if you must resample an image, down sampling generally produces better quality. Upsampling is the opposite of all that. So if performance matters more than quality, then you probably want to upsample. > > I have an internal goal of using less than 1% of the CPU for my 1 second > image drawing so it is > actually quite important for me to know. > > TIA > > Jeff Szuhay > a.k.a tickt...@quartertil2.com <mailto:t...@quartertil2.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: > https://lists.apple.com/mailman/options/cocoa-dev/david.duncan%40apple.com > > This email sent to david.dun...@apple.com -- David Duncan _______________________________________________ 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
