TextureCacheBase: Support dumping individual mipmaps.

Source/Plugins/Plugin_VideoDX9/Src/TextureCache.cpp

@@ -58,9 +58,17 @@ void TextureCache::TCacheEntry::Bind(unsigned int stage)
 	D3D::SetTexture(stage, texture);
 }
 
-bool TextureCache::TCacheEntry::Save(const char filename[])
+bool TextureCache::TCacheEntry::Save(const char filename[], unsigned int level)
 {
-	return SUCCEEDED(PD3DXSaveTextureToFileA(filename, D3DXIFF_PNG, texture, 0));
+	IDirect3DSurface9* surface;
+	HRESULT hr = texture->GetSurfaceLevel(level, &surface);
+	if (FAILED(hr))
+		return false;
+
+	hr = PD3DXSaveSurfaceToFileA(filename, D3DXIFF_PNG, surface, NULL, NULL);
+	surface->Release();
+
+	return SUCCEEDED(hr);
 }
 
 void TextureCache::TCacheEntry::Load(unsigned int width, unsigned int height,

Source/Plugins/Plugin_VideoDX9/Src/TextureCache.h

@@ -52,7 +52,7 @@ private:
 			const float *colmat);
 
 		void Bind(unsigned int stage);
-		bool Save(const char filename[]);
+		bool Save(const char filename[], unsigned int level);
 	};
 
 	TCacheEntryBase* CreateTexture(unsigned int width, unsigned int height,