Allen- this looks great. I didn't know 0.8 had a bezier path either (I'm just starting to use 0.8 today). I'm curious to see how it works.

-Bryan

Oh sweet. I didn't realize that had been added in (I'm using 0.7.3). Thanks for the tip... I'll try it out later.

0.8 has bezier path. See SpritesTest.m.

I've been playing around with the idea of sprites following pre-defined paths. I really just want the ability to move along arbitrary curves... I seem to remember there being a spline or bezier action in the python version of cocos2d, but I'm not sure if it was ever ported to this iPhone branch. I might try to implement it myself later, but just as a test I made the following action:

@implementation TraversePathAction

+(id) actionWithDuration: (ccTime) t path: (NSArray*) path {
	return [[[self alloc] initWithDuration:t path:path] autorelease];
}

-(id) initWithDuration: (ccTime) t path: (NSArray*) path {
	self = [super initWithDuration:t];
	if (self != nil) {
		pathArray = [path retain];
	}
	return self;
}

-(id) copyWithZone: (NSZone *)zone {
	Action *copy = [[[self class] allocWithZone:zone] initWithDuration:[self duration] path:pathArray];
	return copy;
}

-(void) start {
	[super start];

}

-(void) update: (ccTime) t {
	int pathPointCount = [pathArray count];
	int index = (int) ((((float)pathPointCount-1)+0.5f)*t);

	NSValue *value = [pathArray objectAtIndex:index];
	CGPoint movePoint = [value CGPointValue];
	//todo: interpolation

	[target setPosition:movePoint];
}

-(void) dealloc {
	[pathArray release];
	[super dealloc];
}

@end

This works well if you set up the path array with CGPoint objects (contained in NSValue objects) representing a curve, but it needs a significant point resolution to appear smooth. It could be improved (as I noted in the todo) by using interpolation... moving between array points based on the remaining time after integer index truncation.

Have you guys implemented something similar or better?