Comments on: How to implement a basic bitmap brush http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/ smarter than your average squirrel, on most non-acorn related topics Thu, 24 Dec 2009 13:45:24 -0800 http://wordpress.org/?v=2.9.2 hourly 1 By: Robert Collins http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-490 Robert Collins Thu, 10 Jul 2008 22:50:15 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-490 Thanks a lot for sharing this ! Trying to code a little sketch program. Using a wacom for drawing I add modifications to handle tablet pressure for opacity (via NSEvent pressure) but I never found a way to handle smooth curve drawing (I mean drawing stamps along a curve interpolating between mouse locations) Thanks, Robert Thanks a lot for sharing this ! Trying to code a little sketch program.
Using a wacom for drawing I add modifications to handle tablet pressure for opacity (via NSEvent pressure) but I never found a way to handle smooth curve drawing (I mean drawing stamps along a curve interpolating between mouse locations)

Thanks,
Robert

]]> By: Pixeled http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-489 Pixeled Tue, 04 Sep 2007 04:53:09 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-489 > The past tense of ‘drag’ is ‘dragged’, not ‘drug’. bzzt. .thanks for playing. drug 2 [druhg] Pronunciation Key - Show IPA Pronunciation –verb Chiefly Midland and Southern U.S. Nonstandard. a pt. and pp. of drag. and who the hell comments (incorrectly) about grammar in a programming blog. get a fricken life. > The past tense of ‘drag’ is ‘dragged’, not ‘drug’.

bzzt. .thanks for playing.

drug 2 [druhg] Pronunciation Key – Show IPA Pronunciation
–verb Chiefly Midland and Southern U.S. Nonstandard.
a pt. and pp. of drag.

and who the hell comments (incorrectly) about grammar in a programming blog. get a fricken life.

]]> By: Pieter Omvlee http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-488 Pieter Omvlee Sat, 01 Sep 2007 09:51:47 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-488 Just when I was about to implement a brush in my own application... Perfect timing. A few things were new for me, thank you very much. Just when I was about to implement a brush in my own application…
Perfect timing.
A few things were new for me, thank you very much.

]]> By: Thomas C. http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-487 Thomas C. Sat, 25 Aug 2007 01:34:40 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-487 Very well done. Thank you for posting the link on the Quartz mailing list. Very well done. Thank you for posting the link on the Quartz mailing list.

]]> By: Andy http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-486 Andy Fri, 24 Aug 2007 19:19:25 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-486 > What is the difference between this implementation and using NSImage and the associated compositing methods? Probably not much. NSImage is probably heavier than a CGImageRef, but other than that, after creating the brush image, stamping is just compositing. The truth is I was already in CG land with the graphics and just decided to stay there (instead of switching to NSImage). However, I will point out that drawing the brush image into a CGLayerRef (instead of a CGBitmapContext), and then using the CGLayerRef to stamp would give a performance improvement over the current implementation. > What is the difference between this implementation and using NSImage and the associated compositing methods?

Probably not much. NSImage is probably heavier than a CGImageRef, but other than that, after creating the brush image, stamping is just compositing. The truth is I was already in CG land with the graphics and just decided to stay there (instead of switching to NSImage).

However, I will point out that drawing the brush image into a CGLayerRef (instead of a CGBitmapContext), and then using the CGLayerRef to stamp would give a performance improvement over the current implementation.

]]> By: Brian G. http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-485 Brian G. Fri, 24 Aug 2007 03:31:23 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-485 What is the difference between this implementation and using NSImage and the associated compositing methods? What is the difference between this implementation and using NSImage and the associated compositing methods?

]]> By: Michael Tsai - Blog - How to Implement a Basic Bitmap Brush http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-484 Michael Tsai - Blog - How to Implement a Basic Bitmap Brush Thu, 23 Aug 2007 14:20:25 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-484 [...] Andy Finnell: [...] [...] Andy Finnell: [...]

]]> By: sweetie http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-483 sweetie Tue, 21 Aug 2007 18:31:24 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-483 I think you tried to explain it to me, and I sat there and nodded dumbly for about thirty seconds before I realized I was waaaaaay out of my element. I'd always wanted to take a graphics class, and now I'm marrying someone who knows way more than I ever wanted to know. I think that's almost as good, don't you think? I know what you think of perl, but I'll stick to that. :) I think you tried to explain it to me, and I sat there and nodded dumbly for about thirty seconds before I realized I was waaaaaay out of my element.

I’d always wanted to take a graphics class, and now I’m marrying someone who knows way more than I ever wanted to know. I think that’s almost as good, don’t you think?

I know what you think of perl, but I’ll stick to that. :)

]]> By: Andy http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-482 Andy Mon, 20 Aug 2007 18:44:48 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-482 > Now how could one implement a paint bucket ? heh. That's actually the next thing I'm working on (sort of). I'm working on implementing a magic wand tool, which would use the same basic flood fill algorithm as a paint bucket. It's more in depth that a comment on a post could cover. I'm still investigating, but it looks like I'll have to drop down to manipulating the pixel data manually in order to implement it. This sort of makes sense because CoreGraphics doesn't really know about pixels, which is required to implement a flood fill algorithm. > Now how could one implement a paint bucket ?

heh. That’s actually the next thing I’m working on (sort of). I’m working on implementing a magic wand tool, which would use the same basic flood fill algorithm as a paint bucket. It’s more in depth that a comment on a post could cover.

I’m still investigating, but it looks like I’ll have to drop down to manipulating the pixel data manually in order to implement it. This sort of makes sense because CoreGraphics doesn’t really know about pixels, which is required to implement a flood fill algorithm.

]]> By: Andy http://losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/comment-page-1/#comment-481 Andy Mon, 20 Aug 2007 18:38:46 +0000 http://www.losingfight.com/blog/2007/08/18/how-to-implement-a-basic-bitmap-brush/#comment-481 > I think it’s worth pointing out that this kind of thing is far easier to do with a Quartz Composer view. I'm afraid I'm not all that familiar with Quartz Composer view. In what way would this be easier? > I think it’s worth pointing out that this kind of thing is far easier to do with a Quartz Composer view.

I’m afraid I’m not all that familiar with Quartz Composer view. In what way would this be easier?

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