iOS内存使用量变量？

Question

I am developing an iPhone game with cocos2d-iphone.

I am particularly interested in how much memory is CCSpriteFrameCache "holding" at the moment. I am wondering - is there a way to know that? Without using any Xcode tools?

Perhaps there is a variable that will already let me know an estimate memory consumption value on my app?

Answer 1

Generally speaking the problem you are posing is not easy to solve.

In the case of CCSpriteFrameCache , since this class contains a pointer to an NSMutableDictionary of sprite frames, which are textures, you could iterate the dictionary and accumulating the texture dimensions (multiplied by the size of each pixel).

Another approach would be converting the dictionary into NSData like this:

NSData * data = [NSPropertyListSerialization dataFromPropertyList:spriteFrameDictionary
    format:NSPropertyListBinaryFormat_v1_0 errorDescription:NULL];    
NSLog(@"size: %d", [data length]);

but this would require you to implement the NSCoding protocol for the CCSpriteFrame class.

About accumulating the textures size, you can multiply width by height by pixel size; the pixel size depends on the pixel format: RGBA8888 is 32 bits, RGB565 is 16 bits; also you have to take into account that open gl textures have only sizes that are power of 2: 256x256, 512x512, 1024x512 etc.

Answer 2

Actually if you are concerned about memory consumption of your textures, they are stored by CCTextureCache. There is a CCTextureCache (Debug) method called dumpCachedTextureInfo method in there. I have not tried it myself, but here :

@implementation CCTextureCache (Debug)

-(void) dumpCachedTextureInfo
{
NSUInteger count = 0;
NSUInteger totalBytes = 0;
for (NSString* texKey in textures_) {
    CCTexture2D* tex = [textures_ objectForKey:texKey];
    NSUInteger bpp = [tex bitsPerPixelForFormat];
    // Each texture takes up width * height * bytesPerPixel bytes.
    NSUInteger bytes = tex.pixelsWide * tex.pixelsHigh * bpp / 8;
    totalBytes += bytes;
    count++;
    CCLOG( @"cocos2d: \"%@\" rc=%lu id=%lu %lu x %lu @ %ld bpp => %lu KB",
          texKey,
          (long)[tex retainCount],
          (long)tex.name,
          (long)tex.pixelsWide,
          (long)tex.pixelsHigh,
          (long)bpp,
          (long)bytes / 1024 );
}
CCLOG( @"cocos2d: CCTextureCache dumpDebugInfo: %ld textures, for %lu KB (%.2f MB)", (long)count, (long)totalBytes / 1024, totalBytes / (1024.0f*1024.0f));
}

You want to calculate per texture the bit format, since it is possible to store different texture formats in the cache, depending on your current needs. It will give you (last line) the summary of contents, including total memory consumed.