Some more cache management stuff for the audio rendering.

Originally committed to SVN as r3421.

aegisub/src/audio_renderer.cpp

@@ -159,6 +159,12 @@ void AudioRenderer::SetAudioProvider(AudioProvider *_provider)
 }
 
 
+void AudioRenderer::SetCacheMaxSize(size_t max_size)
+{
+	cache_maxsize = max_size;
+}
+
+
 void AudioRenderer::ResetBlockCount()
 {
 	if (provider)
@@ -255,9 +261,10 @@ void AudioRenderer::Render(wxDC &dc, wxPoint origin, int start, int length, bool
 	}
 
 	if (selected)
-		bitmaps_selected.Age(cache_maxsize);
+		bitmaps_selected.Age(cache_maxsize / 8);
 	else
-		bitmaps_normal.Age(cache_maxsize);
+		bitmaps_normal.Age(cache_maxsize / 8);
+	renderer->AgeCache(3 * cache_maxsize / 4);
 }
 
 

aegisub/src/audio_renderer.h

@@ -168,6 +168,16 @@ public:
 	/// depends on the bitmap provider used.)
 	void SetAmplitudeScale(float amplitude_scale);
 
+	/// @brief Set the maximum allowed cache size
+	/// @param max_size Size in bytes that may be used for caching
+	///
+	/// The given max size is not a hard limit and does generally not include overhead
+	/// added by the cache management. The allowed size might be distributed among
+	/// several separate objects.
+	///
+	/// Changing the max cache size does not trigger cache aging.
+	void SetCacheMaxSize(size_t max_size);
+
 	/// @brief Get horizontal zoom
 	/// @return Audio samples per pixel rendering at
 	int GetSamplesPerPixel() const { return pixel_samples; }
@@ -292,4 +302,11 @@ public:
 	/// @brief Change vertical zoom
 	/// @param amplitude_scale Scaling factor to zoom to
 	void SetAmplitudeScale(float amplitude_scale);
+
+	/// @brief Age any caches the renderer might keep
+	/// @param max_size Maximum size in bytes the caches should be
+	///
+	/// Deriving classes should override this method if they implement any
+	/// kind of caching.
+	virtual void AgeCache(size_t max_size) { }
 };