cocos2d for iPhone

A fast, easy to use, free, and community supported 2D game engine

1. 

   CJ
   Moderator

   This would be really helpful if anyone knows how to get a UIImage back from an existing Texture2D.

   Posted 2 years ago #
2. 

   Steve Oldmeadow
   Administrator

   Jason Booth's RenderTexture class could be used for this. It saves the texture to a file but part of doing that is creating a UIImage so it wouldn't be hard to hack your own texture to UIImage method.

   http://code.google.com/p/cocos2d-iphone/source/browse/trunk/cocos2d/RenderTexture.m?spec=svn1233&r=1233

   Posted 2 years ago #
3. 

   CJ
   Moderator

   Thanks for the quick reply :)

   I've been messing with the RenderTexture class for a few hours before I posted my request above.

   I cannot get it to work without actually writing/reading the file.

   I made a copy of the "saveBuffer" method and named it "-(UIImage *)bufferAsUIImage"
   and just removed the stuff about writing to a file and then return the UIImage...
   But at runtime it fails with the error "CGSConvertRGBX8888toRGBA8888"

   Here is the relevant stack trace from the point I try to make a new Texture2D from the UIImage I got from capturing a sprite:

   #0 0x00299d00 in CGSConvertRGBX8888toRGBA8888
   #1 0x002601f4 in RGBA32_image
   #2 0x04fa4ed8 in ripl_Mark
   #3 0x04fa9306 in ripl_BltImage
   #4 0x04f928ac in ripc_RenderImage
   #5 0x04fa1bd8 in ripc_DrawImage
   #6 0x00207ce4 in CGContextDrawImage
   #7 0x00076bd8 in -[Texture2D(Image) initWithImage:] at Texture2D.m:260

   Also, I COULD just use the saveBuffer method and read it back into a UIImage but for some reason I lose alpha channel info even when using PNG format.

   Posted 2 years ago #
4. 

   CJ
   Moderator

   OK... I got it all figured out :)

   Here are the changes I made to RenderTexture
   http://www.copypastecode.com/8403/

   And...
   Now it is trivial to get a UIImage from a Texture2D...

   //This is a method I put into a Category to extend UIImage
   + (UIImage *) imageWithTexture2D:(Texture2D *)texture
   {
   int tx = texture.contentSize.width;
   int ty = texture.contentSize.height;

   RenderTexture *renderer = [[RenderTexture alloc] initWithWidth:tx height:ty];

   Sprite *tempSprite = [Sprite spriteWithTexture:texture];
   tempSprite.anchorPoint = CGPointZero;

   [renderer begin];
   [tempSprite visit];
   [renderer end];

   return [renderer getUIImageFromBuffer];
   }

   BTW, is it possible to get involved directly with the Cocos2D source and commit back to the repo?

   Posted 2 years ago #
5. 

   Steve Oldmeadow
   Administrator

   @CJ - well done. If you look at the Google code page you can see there are a few committers for the cocos2d project so it is possible to get involved as a committer. However, in this circumstance I think the best approach would be to create a patch and either raise an issue or forward the patch to Jason Booth (Slipster216).

   http://code.google.com/p/cocos2d-iphone/

   Posted 2 years ago #
6. 

   slipster216
   Moderator

   Yes, please commit this back to the repro. I meant to do this a while back and never got around to solving the problems. Riq can give you access, or I can merge the changes and submit it if you'd like..

   Posted 2 years ago #
7. 

   slipster216
   Moderator

   Ok, I'll try to submit this back tonight..

   Posted 2 years ago #
8. 

   riq
   Key Master

   thanks slipster216.

   Posted 2 years ago #

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