Refactor texturepaths.cpp and SourceImageCache

src/client/imagegen.cpp

@@ -75,13 +75,14 @@ void SourceImageCache::insert(const std::string &name, video::IImage *img, bool
 		toadd->grab();
 	m_images[name] = toadd;
 }
+
 video::IImage* SourceImageCache::get(const std::string &name)
 {
 	std::map<std::string, video::IImage*>::iterator n;
 	n = m_images.find(name);
 	if (n != m_images.end())
 		return n->second;
-	return NULL;
+	return nullptr;
 }
 
 // Primarily fetches from cache, secondarily tries to read from filesystem
@@ -96,12 +97,12 @@ video::IImage* SourceImageCache::getOrLoad(const std::string &name)
 	video::IVideoDriver *driver = RenderingEngine::get_video_driver();
 	std::string path = getTexturePath(name);
 	if (path.empty()) {
-		infostream<<"SourceImageCache::getOrLoad(): No path found for \""
-				<<name<<"\""<<std::endl;
-		return NULL;
+		infostream << "SourceImageCache::getOrLoad(): No path found for \""
+				<< name << "\"" << std::endl;
+		return nullptr;
 	}
-	infostream<<"SourceImageCache::getOrLoad(): Loading path \""<<path
-			<<"\""<<std::endl;
+	infostream << "SourceImageCache::getOrLoad(): Loading path \"" << path
+			<< "\"" << std::endl;
 	video::IImage *img = driver->createImageFromFile(path.c_str());
 
 	if (img){
@@ -1910,6 +1911,6 @@ video::SColor ImageGen::getImageAverageColor(const video::IImage &image)
 	return c;
 }
 
-void ImageGen::insertImage(const std::string &name, video::IImage *img, bool prefer_local) {
+void ImageGen::insertSourceImage(const std::string &name, video::IImage *img, bool prefer_local) {
 	m_sourcecache.insert(name, img, prefer_local);
 }

src/client/imagegen.h

@@ -23,10 +23,12 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include <string>
 #include "settings.h"
 
-// This file is only for internal generation/modification of images.
-// Use texturesource.h instead to handle textures.
+// This file is only used for internal generation of images.
+// Use texturesource.h to handle textures.
 
 // A cache used for storing source images.
+// (A "source image" is an unmodified image directly taken from the filesystem.)
+// Does not contain modified images.
 class SourceImageCache {
 public:
 	~SourceImageCache();
@@ -35,42 +37,40 @@ class SourceImageCache {
 
 	video::IImage* get(const std::string &name);
 
-	// Primarily fetches from cache, secondarily tries to read from filesystem
+	// Primarily fetches from cache, secondarily tries to read from filesystem.
 	video::IImage *getOrLoad(const std::string &name);
 private:
 	std::map<std::string, video::IImage*> m_images;
 };
 
-/*
- * Generates and caches images.
- * The image name defines the image by filename and texture modifiers.
-*/
+// Generates images using texture modifiers, and caches source images.
 struct ImageGen {
-	/*! Generates an image from a full string like
-	 * "stone.png^mineral_coal.png^[crack:1:0".
-	 * The returned Image should be dropped.
-	 * source_image_names is important to determine when to flush the image from a cache (dynamic media)
-	 */
+	// Generates an image from a full string like "stone.png^mineral_coal.png^[crack:1:0".
+	// The returned Image should be dropped.
+	// source_image_names stores all source images which have been used to generate the image.
+	// It is important to determine when to flush the image from a cache (dynamic media).
 	video::IImage* generateImage(std::string_view name, std::set<std::string> &source_image_names);
 
-	// To add self made images.
-	void insertImage(const std::string &name, video::IImage *img, bool prefer_local);
+	// Insert a source image into the cache without touching the filesystem.
+	void insertSourceImage(const std::string &name, video::IImage *img, bool prefer_local);
 
 	// TODO should probably be moved elsewhere
 	static video::SColor getImageAverageColor(const video::IImage &image);
 
 private:
 
 	// Generate image based on a string like "stone.png" or "[crack:1:0".
-	// if baseimg is NULL, it is created. Otherwise stuff is made on it.
-	// source_image_names is important to determine when to flush the image from a cache (dynamic media)
-	bool generateImagePart(std::string_view part_of_name, video::IImage *& baseimg, std::set<std::string> &source_image_names);
+	// If baseimg is NULL, it is created. Otherwise stuff is made on it.
+	// source_image_names is important to determine when to flush the image from a cache (dynamic media).
+	bool generateImagePart(std::string_view part_of_name, video::IImage *& baseimg,
+			std::set<std::string> &source_image_names);
 
 	// Cache of source images
 	SourceImageCache m_sourcecache;
 
-	// TODO refactor
 	// Cached settings needed for making textures from meshes
+	// Note: Since this is only done once, the game must be restarted
+	// for these settings to take effect.
 	bool m_setting_mipmap = g_settings->getBool("mip_map");
 	bool m_setting_trilinear_filter = g_settings->getBool("trilinear_filter");
 	bool m_setting_bilinear_filter = g_settings->getBool("bilinear_filter");