Physics Editor - Integrating into Pixelwave
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When purchasing Texture Packer I was offered a deal to save some money if I bundle in Physics Editor (http://www.physicseditor.de/). It looked like a good tool and I wasn't sure if I could use it, but I bought it anyways. It turns out I can use it and it was a snap to integrate into our PixelWave project.
There are a couple of things to do:Physics editor contains a helper class called GB2ShapeCache. The method that loads the physics definitions from a plist file into a dictionary but it doesn't match up with Pixelwave's coordinate system. I solved this as follows, but also opened a feature request for Physics Editor and the author suggested an alternate fix - see it here: https://codeandweb.fogbugz.com/default.asp?1298_1o3lsb8kh3sh174bIn the function: -(void) addShapesWithFile:(NSString*)plistchange this code:for (NSString *pointString in polygonArray){CGPoint offset = CGPointFromString_(pointString);vertices[vindex].x = (offset.x / ptmRatio) ;vertices[vindex].y = (offset.y / ptmRatio) ;vindex++;}to this:for (NSString *pointString in [polygonArray reverseObjectEnumerator]){CGPoint offset = CGPointFromString_(pointString);vertices[vindex].x = (offset.x / ptmRatio) ;vertices[vindex].y = -(offset.y / ptmRatio) ;vindex++;}Then in the Box2DUtils class from the Pixelwave examples for box2d I added these two helper methods:+ (b2Body *) staticBodyInWorld:(b2World *)physicsWorldwithPEName:(NSString *)nameforObject:(PXSprite *)obj{b2BodyDef bodyDef;bodyDef.type = b2_staticBody;bodyDef.userData = obj;b2Body *body = physicsWorld->CreateBody(&bodyDef);[[GB2ShapeCache sharedShapeCache] addFixturesToBody:body forShapeName:name];return body;}+ (b2Body *) dynamicBodyInWorld:(b2World *)physicsWorldwithPEName:(NSString *)nameforObject:(PXSprite *)obj{b2BodyDef bodyDef;bodyDef.type = b2_dynamicBody;bodyDef.userData = obj;b2Body *body = physicsWorld->CreateBody(&bodyDef);[[GB2ShapeCache sharedShapeCache] addFixturesToBody:body forShapeName:name];return body;}Then in your code you can just implement something like this:b2Body *body = NULL;body = [Box2DUtils staticBodyInWorld:physicsWorld withPEName:myObject.name forObject:myObject];That's it - Cheers!
