add UncacheSongBanner

stepmania/src/BannerCache.cpp

@@ -25,6 +25,16 @@
  * is missing or disabled.
  */
 
+/* TODO: A way to purge banners.  Right now, if you move songs around, their
+ * banners will be re-cached with their new hash, but the old cache will never
+ * be removed and will still be loaded.  I don't want loading to be dependent on
+ * songs, since I want to be able to put banners into an archive easily later.
+ * Instead, purge banners later, after we load songs.  We can do this fast, since
+ * the banner hash is based only on the banner filename.
+ *
+ * We don't need to embed the banner modification time into the hash: it's already
+ * in the main song cache, so if it changes, the whole song will be re-cached. */
+
 BannerCache *BANNERCACHE;
 
 
@@ -244,6 +254,27 @@ static inline int closest( int num, int n1, int n2 )
 	return n1;
 }
 
+/* Erase the cache for a path. UNTESTED */
+void BannerCache::UncacheSongBanner( CString BannerPath )
+{
+	const CString CachePath = GetBannerCachePath( BannerPath );
+
+	/* If the image is loaded, free it. */
+	if( m_BannerPathToImage.find(BannerPath) != m_BannerPathToImage.end() )
+	{
+		SDL_Surface *img = m_BannerPathToImage[BannerPath];
+		SDL_FreeSurface( img );
+		m_BannerPathToImage.erase(BannerPath);
+	}
+
+	/* Remove the image from the INI. */
+	BannerData.DeleteKey( BannerPath );
+	BannerData.WriteFile();
+
+	/* Erase the cache file. */
+	remove( CachePath.c_str() );
+}
+
 /* We write the cache even if we won't use it, so we don't have to recache everything
  * if the memory or settings change. */
 void BannerCache::CacheSongBanner( CString BannerPath )

stepmania/src/BannerCache.h

@@ -21,6 +21,7 @@ public:
 
 	RageTextureID LoadCachedSongBanner( CString BannerPath );
 	void CacheSongBanner( CString BannerPath );
+	void UncacheSongBanner( CString BannerPath );
 };
 
 extern BannerCache *BANNERCACHE; // global and accessable from anywhere in our program