Comments on: Texture Atlas (Sprite Sheet) Generator

By: Rew

Rew — Fri, 14 Jan 2011 09:15:58 +0000

I’ve taken a look at your test PNGs with the latest version of the tool and they work fine. I’m not sure if there was a fix done previously that isn’t in the version on the site, so I’ve uploaded the latest version. Give it a test and hopefully it’ll work.

By: Rew

Rew — Wed, 12 Jan 2011 14:04:02 +0000

Hi Stando. I’ve sent you an e-mail about the crashing. If you send me some example PNGs that cause it to crash and I’ll take a look. Cheers.

By: Stando

Stando — Wed, 12 Jan 2011 13:45:03 +0000

It seems to me like there is a problem when some of the soucre images have alpha channel and some haven’t.

By: Stando

Stando — Wed, 12 Jan 2011 13:39:12 +0000

Hi. It’s very handy utility but unfortunately it crashes quite a lot of time. I tried it on different machines and always the same problem. Sometimes it helps to enable transparency packing but with some other images it crashes always. I am using about 20 small png images of various sizes (the biggest one has 32 x 32 pixels).

By: Rew

Rew — Wed, 24 Nov 2010 13:05:04 +0000

Hi. My guess would be that the png library is failing to malloc for some reason. Not sure why that would be though. Have you tried including the libpng files directly in your project instead of as a static library? If that works, I’d take a look at your project settings for your app and for the libpng library, to make sure they’re the same.

By: jRayx

jRayx — Wed, 10 Nov 2010 05:25:42 +0000

Hey Rew, first of all thanks for providing this I used your Atlas generator to create a simple atlas with just two sprites to start with. Also, i got the libpng project working correctly as a static library in my atlas test project. The problem i’m having is when the ImageLoad.mm file calls this line : “png_structp pPNGReadStruct = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)” it always returns null.

I spent some time on google trying to find some reason why this would return null to no avail. I was wondering if you had any insight as to why this line would fail.

Btw, my next steps are to just try it on a standard png not generated by your atlas generator. If that doesn’t work i’ll try retrieving the error from that function by passing values into instead of NULL’s.

Thanks again!

By: TMK

TMK — Tue, 25 May 2010 23:11:32 +0000

Ah, cool, that makes sense

Awesome tool by the way, great job

By: Rew

Rew — Tue, 25 May 2010 17:54:01 +0000

Yeah, it adds a 1 pixel border around each sprite so that if there is any filtering when you’re drawing (say, if the texture is resized), then the edges will be filtered with the border pixels. If the border pixels were transparent, then any pixels at the edge of the sprite would be blended with the transparent pixels. Duplicating the ones around the edge eliminates this “bleeding” of colours outside of the image if there is any texture filtering. Hope that makes sense

By: TMK

TMK — Tue, 25 May 2010 02:13:55 +0000

Ah, great program, I’ve been looking for a good sprite atlas builder!

I noticed one small problem, it seems to duplicate the edge pixels, so if you have e.g. a 32×32 image where the edge pixels are black, and the 30×30 center pixels are white, you get an extra black border of pixels around the whole sprite in the generated sprite atlas.

If possible, it would be great if you can remove these extra edge pixels or just make them transparent instead (that way they work as a 1 pixel separator between the sprites as well), thanks