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| * Licensed to the Apache Software Foundation (ASF) under one |
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| |
| #ifndef SD_SLIDESORTER_GENERIC_PAGE_CACHE_HXX |
| #define SD_SLIDESORTER_GENERIC_PAGE_CACHE_HXX |
| |
| #include "SlideSorter.hxx" |
| #include "SlsRequestQueue.hxx" |
| #include <boost/scoped_ptr.hpp> |
| |
| namespace sd { namespace slidesorter { namespace cache { |
| |
| class BitmapCache; |
| class QueueProcessor; |
| |
| /** This basically is the implementation class for the PageCache class. |
| */ |
| class GenericPageCache |
| { |
| public: |
| /** The page chache is created with a reference to the SlideSorter and |
| thus has access to both view and model. This allows the cache to |
| fill itself with requests for all pages or just the visible ones. |
| @param rPreviewSize |
| The size of the previews is expected in pixel values. |
| @param bDoSuperSampling |
| When <TRUE/> the previews are rendered larger and then scaled |
| down to the requested size to improve image quality. |
| */ |
| GenericPageCache ( |
| const Size& rPreviewSize, |
| const bool bDoSuperSampling, |
| const SharedCacheContext& rpCacheContext); |
| |
| ~GenericPageCache (void); |
| |
| /** Change the size of the preview bitmaps. This may be caused by a |
| resize of the slide sorter window or a change of the number of |
| columns. |
| */ |
| void ChangePreviewSize ( |
| const Size& rPreviewSize, |
| const bool bDoSuperSampling); |
| |
| /** Request a preview bitmap for the specified page object in the |
| specified size. The returned bitmap may be a preview of the preview, |
| i.e. either a scaled (up or down) version of a previous preview (of |
| the wrong size) or an empty bitmap. In this case a request for the |
| generation of a new preview is created and inserted into the request |
| queue. When the preview is available the page shape will be told to |
| paint itself again. When it then calls this method again if |
| receives the correctly sized preview bitmap. |
| @param rRequestData |
| This data is used to determine the preview. |
| @param bResize |
| When <TRUE/> then when the available bitmap has not the |
| requested size, it is scaled before it is returned. When |
| <FALSE/> then the bitmap is returned in the wrong size and it is |
| the task of the caller to scale it. |
| @return |
| Returns a bitmap that is either empty, contains a scaled (up or |
| down) version or is the requested bitmap. |
| */ |
| Bitmap GetPreviewBitmap ( |
| const CacheKey aKey, |
| const bool bResize); |
| Bitmap GetMarkedPreviewBitmap ( |
| const CacheKey aKey, |
| const bool bResize); |
| void SetMarkedPreviewBitmap ( |
| const CacheKey aKey, |
| const Bitmap& rMarkedBitmap); |
| |
| /** When the requested preview bitmap does not yet exist or is not |
| up-to-date then the rendering of one is scheduled. Otherwise this |
| method does nothing. |
| @param rRequestData |
| This data is used to determine the preview. |
| @param bMayBeUpToDate |
| This flag helps the method to determine whether an existing |
| preview that matches the request is up to date. If the caller |
| knows that it is not then by passing <FALSE/> he tells us that we |
| do not have to check the up-to-date flag a second time. If |
| unsure use <TRUE/>. |
| */ |
| void RequestPreviewBitmap ( |
| const CacheKey aKey, |
| const bool bMayBeUpToDate = true); |
| |
| /** Tell the cache to replace the bitmap associated with the given |
| request data with a new one that reflects recent changes in the |
| content of the page object. |
| @return |
| When the key is kown then return <TRUE/>. |
| */ |
| bool InvalidatePreviewBitmap (const CacheKey aKey); |
| |
| /** Call this method when a view-object-contact object is being deleted |
| and does not need (a) its current bitmap in the cache and (b) a |
| requested a new bitmap. |
| */ |
| void ReleasePreviewBitmap (const CacheKey aKey); |
| |
| /** Call this method when all preview bitmaps have to be generated anew. |
| This is the case when the size of the page objects on the screen has |
| changed or when the model has changed. |
| */ |
| void InvalidateCache (const bool bUpdateCache); |
| |
| /** With the precious flag you can control whether a bitmap can be |
| removed from the cache or reduced in size to make room for other |
| bitmaps or is so precious that it will not be touched. A typical |
| use is to set the precious flag for the visible pages. |
| */ |
| void SetPreciousFlag (const CacheKey aKey, const bool bIsPrecious); |
| |
| void Pause (void); |
| void Resume (void); |
| |
| private: |
| ::boost::shared_ptr<BitmapCache> mpBitmapCache; |
| |
| RequestQueue maRequestQueue; |
| |
| ::boost::scoped_ptr<QueueProcessor> mpQueueProcessor; |
| |
| SharedCacheContext mpCacheContext; |
| |
| /** The current size of preview bitmaps. |
| */ |
| Size maPreviewSize; |
| |
| bool mbDoSuperSampling; |
| |
| /** Both bitmap cache and queue processor are created on demand by this |
| method. |
| */ |
| void ProvideCacheAndProcessor (void); |
| }; |
| |
| |
| } } } // end of namespace ::sd::slidesorter::cache |
| |
| #endif |