• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: drawing/masking one image with the alpha value from another
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: drawing/masking one image with the alpha value from another


  • Subject: Re: drawing/masking one image with the alpha value from another
  • From: Alastair Houghton <email@hidden>
  • Date: Tue, 22 Sep 2009 09:38:28 +0100

On 22 Sep 2009, at 06:18, Roland King wrote:

I hadn't seen CIFilter, no, that might have been a good avenue to explore however I think that's not available on the phone (and this is for the phone even though I didn't explicitly state that earlier, apologies). So I'll have to use something a bit more primitive.

I think perhaps a bitmap context is what I may want

CIFilter would be ideal, I think, but if you need to work on an environment without it then I think BravoBug Software (whoever that is) was right; you want to grab the data with the -bitmapData method and manipulate it directly yourself.


Of course, that means that you must support any pixel format (and endianness) issues that result, but it does mean you can do what you please with the data.

Using a bitmap context IMO is a red herring... I don't see how it helps you to do what you need, and even if you were to misuse such a thing (e.g. drawing rectangles to fill individual pixels), it'd be horribly slow by comparison to direct image manipulation I think.

Kind regards,

Alastair.

--
http://alastairs-place.net



_______________________________________________

Cocoa-dev mailing list (email@hidden)

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:
This email sent to email@hidden


References: 
 >drawing/masking one image with the alpha value from another (From: Roland King <email@hidden>)
 >Re: drawing/masking one image with the alpha value from another (From: BravoBug Software <email@hidden>)
 >Re: drawing/masking one image with the alpha value from another (From: Roland King <email@hidden>)

  • Prev by Date: Re: NSArrayController addObject or insertObject:atArrangedObjectIndex:
  • Next by Date: WebView and PickerView problem
  • Previous by thread: Re: drawing/masking one image with the alpha value from another
  • Next by thread: Re: drawing/masking one image with the alpha value from another
  • Index(es):
    • Date
    • Thread