Unable to open quartz 2D and body text

Question

I have a problem removing my OpenGL ES textures created using Quartz 2D and Core Text, as shown below:

- (void)drawText:(CGContextRef)contextP startX:(float)x startY:(float) y withText:(NSString *)standString { CGContextTranslateCTM(contextP, 0, (bottom-top)*2); CGContextScaleCTM(contextP, 1.0, -1.0); CGRect frameText = CGRectMake(1, 0, (right-left)*2, (bottom-top)*2); NSMutableAttributedString * attrString = [[NSMutableAttributedString alloc] initWithString:standString]; [attrString addAttribute:NSFontAttributeName value:[UIFont fontWithName:@"Helvetica-Bold" size:12.0] range:NSMakeRange(0, attrString.length)]; CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((__bridge CFAttributedStringRef)(attrString)); struct CGPath * p = CGPathCreateMutable(); CGPathAddRect(p, NULL, frameText); CTFrameRef frame = CTFramesetterCreateFrame(framesetter, CFRangeMake(0,0), p, NULL); CTFrameDraw(frame, contextP); CFRelease(framesetter); CFRelease(frame); CGPathRelease(p); standString = nil; attrString = nil; } - (UIImage *)drawTexture : (NSArray *)verticesPassed : (UIColor *)statusColour : (NSString *)standString { CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB(); CGRect shp = [self boundFromFrame:verticesPassed]; CGContextRef conPattern = CGBitmapContextCreate(NULL, shp.size.width*sceneScalar, shp.size.height*sceneScalar, 8, 0, rgbColorSpace, (CGBitmapInfo)kCGImageAlphaPremultipliedFirst); CGColorSpaceRelease(rgbColorSpace); CGContextSetLineWidth(conPattern, 2); CGContextSetStrokeColorWithColor(conPattern, [UIColor blackColor].CGColor); Line * start = [sortedVertices objectAtIndex:0]; StandPoint * startPoint = start.origin; CGContextMoveToPoint(conPattern, ([startPoint.x floatValue]-shp.origin.x)*sceneScalar , ([startPoint.y floatValue]-shp.origin.y)*sceneScalar); for (Line * vertice in sortedVertices) { StandPoint * standPoint = vertice.origin; CGContextAddLineToPoint(conPattern, ([standPoint.x floatValue]-shp.origin.x)*sceneScalar, ([standPoint.y floatValue]-shp.origin.y)*sceneScalar); } CGContextAddLineToPoint(conPattern, ([startPoint.x floatValue]-shp.origin.x)*sceneScalar , ([startPoint.y floatValue]-shp.origin.y)*sceneScalar); CGContextSetFillColorWithColor(conPattern, statusColour.CGColor); CGContextDrawPath(conPattern, kCGPathFillStroke); [self drawText:conPattern startX:0 startY:20 withText:standString]; CGImageRef cgImage = CGBitmapContextCreateImage(conPattern); UIImage *imgPattern = [[UIImage alloc]initWithCGImage:cgImage]; //UIImageWriteToSavedPhotosAlbum(imgPattern, nil, nil, nil); Uncomment if you need to view textures (photo album). self.standHeight = (top - bottom)*sceneScalar; self.standWidth = (right - left)*sceneScalar; self.xOffset = [startPoint.x floatValue]*sceneScalar; self.yOffset = (-[startPoint.y floatValue]*sceneScalar)+standHeight; CFRelease(cgImage); CGContextRelease(conPattern); return imgPattern; } 

However, when I try to remove textures as follows in viewWillDisappear, I see (in tools) that the memory is not freed:

 for (PolygonObject * stand in standArray) { GLuint name = stand.textureInfo.name; // delete texture from opengl glDeleteTextures(1, &name); // set texture info to nil stand.textureInfo = nil; } 

I think something is stored in the texture somewhere in the code above. Can anyone suggest where?

Answer 1

As far as I can see, there is no memory leak in your code if you use ARC. However, the UIImage returned from drawTexture may be retained by some other objects or by the automatic release pool.

To check if this is true, you can subclass UIImage, such as UIDebugImage, override the dealloc method and set a breakpoint there to see if it called.