Objective c 无法释放Quartz 2D和Core文本创建的图像

我在删除通过Quartz 2D和Core文本创建的OpenGL ES纹理时遇到问题，如下所示：

- (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;

}

但是，当我尝试在VIEWWILLOVERE中删除以下纹理时，我可以看到（在仪器中）内存没有释放：

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;
        }

---

我认为在上面代码的某个地方纹理中保留了一些东西。有人能告诉我在哪里吗？

据我所知，如果使用ARC，代码中不会出现内存泄漏。但是，从drawTexture返回的UIImage可能会被其他一些对象或自动释放池保留

---

若要检查是否存在这种情况，您可以将UIImage子类化，例如UIDebugImage，覆盖dealloc方法并在那里设置断点，以查看是否调用了它。

检查您的CTFramesetterRef，使用answerlooks释放，就像OpenGL中没有的问题一样，尝试创建图像并删除，而不创建纹理。并在-[UIImage imageWithCGImage:]上替换