Re: +{NSImage imageNamed:fromBundle:]?

FROM : glenn andreas
DATE : Fri Jan 11 23:12:49 2008

On Jan 11, 2008, at 3:34 PM, Ricky Sharp wrote:

>
> On Jan 11, 2008, at 2:10 PM, glenn andreas wrote:
>

>> NSImage's +imageNamed: is documented as searching the named images 
>> cache, the apps main bundle, and then the AppKit framework bundle. 
>> Unfortunately, I've got code in a private framework that wants to 
>> get the image stored that framework (which isn't thus searched).
>>
>> Is there some way to add a framework to this search path?  (Which 
>> would be best, because it will allow any object, such as a button, 
>> that has an image name to automatically work correctly) Or at least 
>> a way to explicitly pass a bundle to search (via a hypothetical 
>> +imageNamed:fromBundle:).  The fall back, of course, is to get all 
>> the possible file extensions from NSImage and manually try each and 
>> every one of them, but I'd rather not have to duplicate this logic 
>> (plus this fails to support the generic button using a named image 
>> that resides in the private framework)...

>
> As others have pointed out, use NSBundle's pathForImageResource.  I 
> created an image factory that knows how to scan multiple areas 
> looking for images.


I've added code to explicitly call that, which seems to work (for a 
limited use where I know that I'm going to need that image), but the 
more I look at it, the more I want a global version that will update 
the cache so that plain old +imageNamed: works correctly (since it 
seems silly to subclass everything with an image to not only have to 
look for the image in a loaded framework, but to also have to then end 
up hard coding the image name, since pretty much nothing with an image 
lets you access the name of the image).

>
>

>> I suppose I could also, at startup, go through all the images in 
>> the framework, load them, and then do a "setName:" to get them in 
>> the cache (but this seems like it could impact program launch times)

>
>
> Well, that may not be bad since load times are often very, very 
> low.  It's probably the case where image data is not decoded until 
> you're actually drawing things.
>
> For example, all my images are PDF (to support res-ind).  While my 
> factory loads them on-demand (and not all at once), I did measure 
> the total loading time over the lifetime of the app.  This was the 
> time taken to actually alloc/init NSImage images and then call 
> setName:.
>
> When the images were then _drawn_, that's where the bulk of the time 
> was taken.  Maybe this is specific to PDF; I don't know.  For PDF 
> the raw data is loaded, but not "decoded" until drawn; also at the 
> time of drawing, that's where you end up with cached reps (e.g. a 
> cached bitmapimagerep) that will ultimately speed up drawing for the 
> 2nd, etc. times the image is drawn.



Yeah, I probably shouldn't be doing the premature optimization - 
there's about 70 or so images currently, so I figured it would be 
better to just try to load them at start up (most of them are png or 
tiff files):

@interface NSBundle(NameCacheImages)
- (void) cacheNamedImages;
@end
@implementation NSBundle(NameCacheImages)
- (void) cacheNamedImages;
{
    NSArray *types = [NSImage imageFileTypes];
    NSEnumerator *e = [types objectEnumerator];
    NSString *type;
    while ((type = [e nextObject]) != nil) {
   NSArray *files = [self pathsForResourcesOfType: type inDirectory: nil];
   NSEnumerator *e2 = [files objectEnumerator];
   NSString *path;
   while ((path = [e2 nextObject]) != nil) {
       NSString *name = [[path lastPathComponent] 
stringByDeletingPathExtension];
       NSImage *image = [NSImage imageNamed:name];
       if (!image) {
       NSImage *image = [[NSImage alloc]  initByReferencingFile:path];
       if (image) {
           [image setName: name];
       }
       }
   }
    }
}
@end

The result was that it cruised through the 74 images in 0.084809 
seconds, so I think I can live with that...


Glenn Andreas                      <email_removed>
  <http://www.gandreas.com/> wicked fun!
quadrium2 | build, mutate, evolve, animate  | images, textures, 
fractals, art