生成 OpenGL ES 纹理后释放 UIImage 时程序崩溃答案

【问题标题】：Program crashes when releases UIImage after generating OpenGL ES texture生成 OpenGL ES 纹理后释放 UIImage 时程序崩溃
【发布时间】：2009-09-11 14:57:06
【问题描述】：

现在，我已经按照这个教程学习了：

http://iphonedevelopment.blogspot.com/2009/05/opengl-es-from-ground-up-part-6_25.html

如果我尝试释放 UIImage，它不起作用：我会得到一个“EXC_BAD_ACCESS”。现在，我将 UIImage 设为实例变量并保留它们。我不让它自动释放。但问题是有时我想删除我的纹理。我需要释放那些 UIImage 否则我会泄漏。（Performance Tool Leaks 报告说 UIImage 会导致泄漏）但是如果我释放 UIImage，我会得到 EXC_BAD_ACCESS。而且我什至根本没有在任何地方绘制它们或访问它们。该程序只是在它发布的地方崩溃：

#0  0x30011940 in objc_msgSend ()
#1  0x302395f4 in CFGetTypeID ()
#2  0x308f480c in -[UIImage(UIImageDeprecated) imageRef] ()
#3  0x308f4ae0 in SharedIdentifierForImage ()
#4  0x308f4a30 in _UISharedImageDealloc ()
#5  0x308f4964 in -[UIImage dealloc] ()
#6  0x30236b78 in -[NSObject release] ()
#7  0x0000a374 in -[Texture dealloc] (self=0x184b30, _cmd=0x300f7fd0) at /Users/akaraphan/Desktop/Competition/TrapRoom/Classes/Texture.m:329
#8  0x30236b78 in -[NSObject release] ()
#9  0x30235f24 in CFRelease ()
#10 0x302043bc in __CFTypeCollectionRelease ()
#11 0x30205dac in __CFArrayReleaseValues ()
#12 0x30205c18 in __CFArrayDeallocate ()
#13 0x30236020 in _CFRelease ()
#14 0x30235efe in CFRelease ()
#15 0x3054836a in -[NSCFArray release] ()
#16 0x00011658 in -[GameSprite dealloc] (self=0x1838d0, _cmd=0x300f7fd0) at /Users/akaraphan/Desktop/Competition/TrapRoom/Classes/GameSprite.m:40
...
...

Texture.m 中的第 329 行是我发布 UIImage 的地方。

我的代码与教程略有不同，但应该非常相似：

- (id) initFromImage: (NSString*)imageFile{

    if (self = [super init]){

        path = [[NSBundle mainBundle] pathForResource:imageFile ofType:@"png"];
        texData = [[NSData alloc] initWithContentsOfFile:path];
        img = [[UIImage alloc] initWithData:texData];

        CGImageRef image = img.CGImage;

        width = CGImageGetWidth(image);
        height = CGImageGetHeight(image);

        if (image){
            int tempWidth = (int)width, tempHeight = (int)height;

            if ((tempWidth & (tempWidth - 1)) != 0 ){
                NSLog(@"CAUTION! width is not power of 2. width == %d", tempWidth);
            }else if ((tempHeight & (tempHeight - 1)) != 0 ){
                NSLog(@"CAUTION! height is not power of 2. height == %d", tempHeight);
            }else{
                GLubyte *spriteData = (GLubyte*) calloc(width * 4, height * 4);

                CGContextRef spriteContext = CGBitmapContextCreate(spriteData, width, height, 8, width*4, CGImageGetColorSpace(image), kCGImageAlphaPremultipliedLast);

                CGContextDrawImage(spriteContext, CGRectMake(0.0, 0.0, width, height), image);

                CGContextRelease(spriteContext);

                glGenTextures(1, &GLtexture);

                glBindTexture(GL_TEXTURE_2D, GLtexture);

                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, spriteData);

                free(spriteData);

                CGImageRelease(image);

                NSLog(@"Texture %d", GLtexture);

            }

        }else NSLog(@"ERROR: Image not loaded...");

        return self;
    }
    return nil;
}

如果你能看出什么问题，请指导我。谢谢。

【问题讨论】：

标签： opengl-es uiimage textures

【解决方案1】：

不知何故删除

CGImageRelease(image)

解决了这个问题。之后我可以毫无问题地删除 UIImage 并且也没有泄漏。

【讨论】：