haneke / hanekeswift Goto Github PK

Format currently has logic that is specific to images. This will have to go elsewhere. Maybe into something like ImageTransformer : Transformer, of which Format has an instance.

Allow to associate a format with a UIImageView. Return a format that describes the UIImageView if none is given.

I'll do it as soon we merge all current PRs.

Formats acts as cache buckets, a secondary key for setting/fetching/removing objects from the cache.

For the scope of this issue, formats must have a name which should be also the name of the directory where its images are stored.

In the original Haneke, only Cache knows about formats. Each format has its DiskCache, so DiskCache doesn't know about them.

Apply format when fetching an original image from its entity.

Each format must have its own disk capacity.

Fetches an image from disk.

Allow to specify the desired compression quality at format level.

Singleton cache to be used in UIKit extensions.

We can't associate a format with a UIImageView because formats are structs.

As a workaround, the various setImage* methods can take a format argument.

Fetches an image from the network.

The name Entity does not convey the responsibilities declared by the protocol. It's too vague. Should we rename it?

Ideas:

• Fetcher: an entity basically fetches and object to be cached
• Cacheable
• CacheObject (should be CacheImage, but I'm thinking of Cache being generic)
• LazyObject

Use arbitrary capacity for now.

Should we prefix extension functions? E.g., hnk_hasAlpha in the UIImage extension.

On one hand Swift is not dynamic so collisions would generate compiler errors.

On the other hand, I have no idea what would happen if compiled code runs in a future iOS version in which one of our extension methods is added.

What one should we follow?

Support image resizing by specifying the desired image size in the format.

Images must be resized in background prior to being cached.

Allow formats to define pre-resize and post-resize transformations (e.g., rounded corners) for the images.

Entities should be objects that know how to fetch an image asynchronously. These can be given to the Cache instead of a key when fetching.

Also, add image to memory cache after reading it from disk.

Support scaling modes by specifying them in formats. In particular: Fill, Aspect fill, Aspect fit, and No scaling.

Additionally, allow formats to define if images can be upscaled or not.

Allow formats to have a "parent" format. If an image is not available in the cache, Haneke should attempt to create it from the parent format (if any). This should work recursively.

For example, this is useful when you have a "fullsize" format and a "thumbnail" format. "fullsize" would be the "thumbnail" parent.

This feature is not currently available in the original Haneke.