Do i need to call [convertToGl]? - cocos2d-iphone

Question

i'm using cocos2d and i have subclassed cccnode (i want to draw circles and that works)
.h
#interface CCSpriteCircle : CCSprite {
float radius;
float angle; //in radians
NSUInteger segments;
BOOL drawLineToCenter;
ccColor4B cColor;
}
-(id) initWithRadius: (float)radius_ withAngle: (float)angle_ withSegments: (NSUInteger)segments_ withDrawLineToCenter:(BOOL)drawLineToCenter_;
#property(nonatomic,assign) float radius;
#property(nonatomic,assign) float angle;
#property(nonatomic,assign) NSUInteger segments;
#property(nonatomic,assign) BOOL drawLineToCenter;
#property(nonatomic,assign) ccColor4B cColor;
#end
//my .m file
#implementation CCSpriteCircle
#synthesize radius, angle,segments,drawLineToCenter,cColor;
-(id) initWithRadius: (float)radius_ withAngle: (float)angle_ withSegments: (NSUInteger)segments_ withDrawLineToCenter:(BOOL)drawLineToCenter_
{
if( (self=[super init])) {
self.radius = radius_;
self.angle = angle_;
self.segments = segments_;
self.drawLineToCenter = drawLineToCenter_;
//[self draw];
}
return self;
}
-(void)draw {
glLineWidth(1);
glColor4ub(cColor.r, cColor.g, cColor.b, cColor.a);
ccDrawCircle(ccp(self.position.x,self.position.y), radius, angle, segments, drawLineToCenter);
// restore original values
glLineWidth(1);
glColor4ub(255,255,255,255);
glPointSize(1);
}
#end
All works fine except that if i place the center of my ccspritecircle to 480 (that's the end of the screen) it doesnt appears but if i place it to 200px it's at the end of the screen.
if i change the position code in my helloworld scene like this:
from:
circle_.position = ccp(480, 0);
to:
circle_.position = [[CCDirector sharedDirector] convertToGL: CGPointMake(480,0)];
then i dont see the circle anymore. Am i doing something wrong?

Answer 1

If your only purpose is to draw a custom circle, without any other form of graphics (image files) then you should subclass CCNode, not CCSprite. CCSprite is a special type of CCNode that handles the loading and display of graphics files.
You should also call "[super draw]" from inside your override, to ensure that additional processing is done correctly - this can either be before or after your code, depending on how it affects your end result.
ccDrawCircle is already converting the x/y coordinates to GL space, so you don't need to worry about that either.
Your CCNode's anchorPoint and position could be a factor here though. The default 0.5/0.5 anchorPoint should set the center of your circle at the x/y position of your node so (480,0) with a radius of 32 would put a 64x64 circle at the bottom right of the screen (in portrait) and you would only be able to see the top-left quadrant of the circle.
You say that setting it to 200px places it at the end of the screen, without seeing how the circle was initialized, it's hard to identify why this would occur - but it more than likely has to do with the radius of the circle your using.
Keep in mind that changing the anchorPoint may not affect the rendering of the circle as your "draw" method is not taking into account the current anchorPoint, so it may be placing the circle at the x/y irregardless of anchorPoint settings.