A global cache of images that have been loaded from files or memory. More...
Inherits DeletedAtShutdown, and Timer.
Static Public Member Functions | |
| static Image * | getFromFile (const File &file) |
| Loads an image from a file, (or just returns the image if it's already cached). | |
| static Image * | getFromMemory (const void *imageData, int dataSize) |
| Loads an image from an in-memory image file, (or just returns the image if it's already cached). | |
| static void | release (Image *imageToRelease) |
| Releases an image that was previously created by the ImageCache. | |
| static void | releaseOrDelete (Image *imageToRelease) |
| Releases an image if it's in the cache, or deletes it if it isn't cached. | |
| static bool | isImageInCache (Image *imageToLookFor) |
| Checks whether an image is in the cache or not. | |
| static void | incReferenceCount (Image *image) |
| Increments the reference-count for a cached image. | |
| static Image * | getFromHashCode (int64 hashCode) |
| Checks the cache for an image with a particular hashcode. | |
| static void | addImageToCache (Image *image, int64 hashCode) |
| Adds an image to the cache with a user-defined hash-code. | |
| static void | setCacheTimeout (int millisecs) |
| Changes the amount of time before an unused image will be removed from the cache. | |
A global cache of images that have been loaded from files or memory.
If you're loading an image and may need to use the image in more than one place, this is used to allow the same image to be shared rather than loading multiple copies into memory.
Another advantage is that after images are released, they will be kept in memory for a few seconds before it is actually deleted, so if you're repeatedly loading/deleting the same image, it'll reduce the chances of having to reload it each time.
Loads an image from a file, (or just returns the image if it's already cached).
If the cache already contains an image that was loaded from this file, that image will be returned. Otherwise, this method will try to load the file, add it to the cache, and return it.
It's very important not to delete the image that is returned - instead use the ImageCache::release() method.
Also, remember that the image returned is shared, so drawing into it might affect other things that are using it!
| file | the file to try to load |
| static Image* ImageCache::getFromMemory | ( | const void * | imageData, | |
| int | dataSize | |||
| ) | [static] |
Loads an image from an in-memory image file, (or just returns the image if it's already cached).
If the cache already contains an image that was loaded from this block of memory, that image will be returned. Otherwise, this method will try to load the file, add it to the cache, and return it.
It's very important not to delete the image that is returned - instead use the ImageCache::release() method.
Also, remember that the image returned is shared, so drawing into it might affect other things that are using it!
| imageData | the block of memory containing the image data | |
| dataSize | the data size in bytes |
| static void ImageCache::release | ( | Image * | imageToRelease | ) | [static] |
Releases an image that was previously created by the ImageCache.
If an image has been returned by the getFromFile() or getFromMemory() methods, it mustn't be deleted directly, but should be released with this method instead.
| static void ImageCache::releaseOrDelete | ( | Image * | imageToRelease | ) | [static] |
Releases an image if it's in the cache, or deletes it if it isn't cached.
This is a handy function to use if you want to delete an image but are afraid that it might be cached.
| static bool ImageCache::isImageInCache | ( | Image * | imageToLookFor | ) | [static] |
Checks whether an image is in the cache or not.
| static void ImageCache::incReferenceCount | ( | Image * | image | ) | [static] |
Increments the reference-count for a cached image.
If the image isn't in the cache, this method won't do anything.
Checks the cache for an image with a particular hashcode.
If there's an image in the cache with this hashcode, it will be returned, otherwise it will return zero.
If an image is returned, it must be released with the release() method when no longer needed, to maintain the correct reference counts.
| hashCode | the hash code that would have been associated with the image by addImageToCache() |
Adds an image to the cache with a user-defined hash-code.
After calling this, responsibilty for deleting the image will be taken by the ImageCache.
The image will be initially be given a reference count of 1, so call the release() method to delete it.
| image | the image to add | |
| hashCode | the hash-code to associate with it |
| static void ImageCache::setCacheTimeout | ( | int | millisecs | ) | [static] |
Changes the amount of time before an unused image will be removed from the cache.
By default this is about 5 seconds.
1.6.3
