Merge pull request #98071 from BlueCube3310/res-import-tex-clean

Clean up ResourceImporterTexture

editor/import/resource_importer_texture.cpp

@@ -46,7 +46,6 @@ void ResourceImporterTexture::_texture_reimport_roughness(const Ref<CompressedTe
 	ERR_FAIL_COND(p_tex.is_null());
 
 	MutexLock lock(singleton->mutex);
-
 	StringName path = p_tex->get_path();
 
 	if (!singleton->make_flags.has(path)) {
@@ -62,7 +61,6 @@ void ResourceImporterTexture::_texture_reimport_3d(const Ref<CompressedTexture2D
 	ERR_FAIL_COND(p_tex.is_null());
 
 	MutexLock lock(singleton->mutex);
-
 	StringName path = p_tex->get_path();
 
 	if (!singleton->make_flags.has(path)) {
@@ -76,7 +74,6 @@ void ResourceImporterTexture::_texture_reimport_normal(const Ref<CompressedTextu
 	ERR_FAIL_COND(p_tex.is_null());
 
 	MutexLock lock(singleton->mutex);
-
 	StringName path = p_tex->get_path();
 
 	if (!singleton->make_flags.has(path)) {
@@ -86,79 +83,87 @@ void ResourceImporterTexture::_texture_reimport_normal(const Ref<CompressedTextu
 	singleton->make_flags[path].flags |= MAKE_NORMAL_FLAG;
 }
 
+inline void ResourceImporterTexture::_print_callback_message(const String &p_message) {
+#ifdef TOOLS_ENABLED
+	EditorToaster::get_singleton()->popup_str(p_message);
+#endif
+	print_line(p_message);
+}
+
 void ResourceImporterTexture::update_imports() {
 	if (EditorFileSystem::get_singleton()->is_scanning() || EditorFileSystem::get_singleton()->is_importing()) {
-		return; // do nothing for now
+		return; // Don't update when EditorFileSystem is doing something else.
 	}
 
 	MutexLock lock(mutex);
 	Vector<String> to_reimport;
-	{
-		if (make_flags.is_empty()) {
-			return;
+
+	if (make_flags.is_empty()) {
+		return;
+	}
+
+	for (const KeyValue<StringName, MakeInfo> &E : make_flags) {
+		Ref<ConfigFile> cf;
+		cf.instantiate();
+		String src_path = String(E.key) + ".import";
+
+		Error err = cf->load(src_path);
+		ERR_CONTINUE(err != OK);
+
+		bool changed = false;
+
+		if (E.value.flags & MAKE_NORMAL_FLAG && int(cf->get_value("params", "compress/normal_map")) == 0) {
+			_print_callback_message(
+					vformat(TTR("%s: Texture detected as used as a normal map in 3D. Enabling red-green texture compression to reduce memory usage (blue channel is discarded)."),
+							String(E.key)));
+
+			cf->set_value("params", "compress/normal_map", 1);
+			changed = true;
 		}
 
-		for (const KeyValue<StringName, MakeInfo> &E : make_flags) {
-			Ref<ConfigFile> cf;
-			cf.instantiate();
-			String src_path = String(E.key) + ".import";
+		if (E.value.flags & MAKE_ROUGHNESS_FLAG && int(cf->get_value("params", "roughness/mode")) == 0) {
+			_print_callback_message(
+					vformat(TTR("%s: Texture detected as used as a roughness map in 3D. Enabling roughness limiter based on the detected associated normal map at %s."),
+							String(E.key), E.value.normal_path_for_roughness));
 
-			Error err = cf->load(src_path);
-			ERR_CONTINUE(err != OK);
+			cf->set_value("params", "roughness/mode", E.value.channel_for_roughness + 2);
+			cf->set_value("params", "roughness/src_normal", E.value.normal_path_for_roughness);
+			changed = true;
+		}
 
-			bool changed = false;
+		if (E.value.flags & MAKE_3D_FLAG && bool(cf->get_value("params", "detect_3d/compress_to"))) {
+			const int compress_to = cf->get_value("params", "detect_3d/compress_to");
 
-			if (E.value.flags & MAKE_NORMAL_FLAG && int(cf->get_value("params", "compress/normal_map")) == 0) {
-				String message = vformat(TTR("%s: Texture detected as used as a normal map in 3D. Enabling red-green texture compression to reduce memory usage (blue channel is discarded)."), String(E.key));
-#ifdef TOOLS_ENABLED
-				EditorToaster::get_singleton()->popup_str(message);
-#endif
-				print_line(message);
-				cf->set_value("params", "compress/normal_map", 1);
-				changed = true;
-			}
+			// 3D detected, disable the callback.
+			cf->set_value("params", "detect_3d/compress_to", 0);
 
-			if (E.value.flags & MAKE_ROUGHNESS_FLAG && int(cf->get_value("params", "roughness/mode")) == 0) {
-				String message = vformat(TTR("%s: Texture detected as used as a roughness map in 3D. Enabling roughness limiter based on the detected associated normal map at %s."), String(E.key), E.value.normal_path_for_roughness);
-#ifdef TOOLS_ENABLED
-				EditorToaster::get_singleton()->popup_str(message);
-#endif
-				print_line(message);
-				cf->set_value("params", "roughness/mode", E.value.channel_for_roughness + 2);
-				cf->set_value("params", "roughness/src_normal", E.value.normal_path_for_roughness);
-				changed = true;
-			}
+			String compress_string;
+			if (compress_to == 1) {
+				cf->set_value("params", "compress/mode", COMPRESS_VRAM_COMPRESSED);
+				compress_string = "VRAM Compressed (S3TC/ETC/BPTC)";
 
-			if (E.value.flags & MAKE_3D_FLAG && bool(cf->get_value("params", "detect_3d/compress_to"))) {
-				const int compress_to = cf->get_value("params", "detect_3d/compress_to");
-				String compress_string;
-				cf->set_value("params", "detect_3d/compress_to", 0);
-				if (compress_to == 1) {
-					cf->set_value("params", "compress/mode", COMPRESS_VRAM_COMPRESSED);
-					compress_string = "VRAM Compressed (S3TC/ETC/BPTC)";
-				} else if (compress_to == 2) {
-					cf->set_value("params", "compress/mode", COMPRESS_BASIS_UNIVERSAL);
-					compress_string = "Basis Universal";
-				}
-				String message = vformat(TTR("%s: Texture detected as used in 3D. Enabling mipmap generation and setting the texture compression mode to %s."), String(E.key), compress_string);
-#ifdef TOOLS_ENABLED
-				EditorToaster::get_singleton()->popup_str(message);
-#endif
-				print_line(message);
-				cf->set_value("params", "mipmaps/generate", true);
-				changed = true;
+			} else if (compress_to == 2) {
+				cf->set_value("params", "compress/mode", COMPRESS_BASIS_UNIVERSAL);
+				compress_string = "Basis Universal";
 			}
 
-			if (changed) {
-				cf->save(src_path);
-				to_reimport.push_back(E.key);
-			}
+			_print_callback_message(
+					vformat(TTR("%s: Texture detected as used in 3D. Enabling mipmap generation and setting the texture compression mode to %s."),
+							String(E.key), compress_string));
+
+			cf->set_value("params", "mipmaps/generate", true);
+			changed = true;
 		}
 
-		make_flags.clear();
+		if (changed) {
+			cf->save(src_path);
+			to_reimport.push_back(E.key);
+		}
 	}
 
-	if (to_reimport.size()) {
+	make_flags.clear();
+
+	if (!to_reimport.is_empty()) {
 		EditorFileSystem::get_singleton()->reimport_files(to_reimport);
 	}
 }
@@ -189,21 +194,25 @@ bool ResourceImporterTexture::get_option_visibility(const String &p_path, const
 		if (compress_mode != COMPRESS_VRAM_COMPRESSED) {
 			return false;
 		}
+
 	} else if (p_option == "compress/lossy_quality") {
 		int compress_mode = int(p_options["compress/mode"]);
 		if (compress_mode != COMPRESS_LOSSY) {
 			return false;
 		}
+
 	} else if (p_option == "compress/hdr_mode") {
 		int compress_mode = int(p_options["compress/mode"]);
 		if (compress_mode < COMPRESS_VRAM_COMPRESSED) {
 			return false;
 		}
+
 	} else if (p_option == "compress/normal_map") {
 		int compress_mode = int(p_options["compress/mode"]);
 		if (compress_mode == COMPRESS_LOSSLESS) {
 			return false;
 		}
+
 	} else if (p_option == "mipmaps/limit") {
 		return p_options["mipmaps/generate"];
 	}
@@ -260,9 +269,9 @@ void ResourceImporterTexture::get_import_options(const String &p_path, List<Impo
 void ResourceImporterTexture::save_to_ctex_format(Ref<FileAccess> f, const Ref<Image> &p_image, CompressMode p_compress_mode, Image::UsedChannels p_channels, Image::CompressMode p_compress_format, float p_lossy_quality) {
 	switch (p_compress_mode) {
 		case COMPRESS_LOSSLESS: {
-			bool lossless_force_png = GLOBAL_GET("rendering/textures/lossless_compression/force_png") ||
-					!Image::_webp_mem_loader_func; // WebP module disabled.
-			bool use_webp = !lossless_force_png && p_image->get_width() <= 16383 && p_image->get_height() <= 16383; // WebP has a size limit
+			bool lossless_force_png = GLOBAL_GET("rendering/textures/lossless_compression/force_png") || !Image::_webp_mem_loader_func; // WebP module disabled or png is forced.
+			bool use_webp = !lossless_force_png && p_image->get_width() <= 16383 && p_image->get_height() <= 16383; // WebP has a size limit.
+
 			f->store_32(use_webp ? CompressedTexture2D::DATA_FORMAT_WEBP : CompressedTexture2D::DATA_FORMAT_PNG);
 			f->store_16(p_image->get_width());
 			f->store_16(p_image->get_height());
@@ -276,11 +285,11 @@ void ResourceImporterTexture::save_to_ctex_format(Ref<FileAccess> f, const Ref<I
 				} else {
 					data = Image::png_packer(i ? p_image->get_image_from_mipmap(i) : p_image);
 				}
-				int data_len = data.size();
-				f->store_32(data_len);
 
-				const uint8_t *r = data.ptr();
-				f->store_buffer(r, data_len);
+				const uint64_t data_size = data.size();
+
+				f->store_32(data_size);
+				f->store_buffer(data.ptr(), data_size);
 			}
 
 		} break;
@@ -293,16 +302,15 @@ void ResourceImporterTexture::save_to_ctex_format(Ref<FileAccess> f, const Ref<I
 
 			for (int i = 0; i < p_image->get_mipmap_count() + 1; i++) {
 				Vector<uint8_t> data = Image::webp_lossy_packer(i ? p_image->get_image_from_mipmap(i) : p_image, p_lossy_quality);
-				int data_len = data.size();
-				f->store_32(data_len);
+				const uint64_t data_size = data.size();
 
-				const uint8_t *r = data.ptr();
-				f->store_buffer(r, data_len);
+				f->store_32(data_size);
+				f->store_buffer(data.ptr(), data_size);
 			}
+
 		} break;
 		case COMPRESS_VRAM_COMPRESSED: {
 			Ref<Image> image = p_image->duplicate();
-
 			image->compress_from_channels(p_compress_format, p_channels);
 
 			f->store_32(CompressedTexture2D::DATA_FORMAT_IMAGE);
@@ -310,11 +318,8 @@ void ResourceImporterTexture::save_to_ctex_format(Ref<FileAccess> f, const Ref<I
 			f->store_16(image->get_height());
 			f->store_32(image->get_mipmap_count());
 			f->store_32(image->get_format());
+			f->store_buffer(image->get_data());
 
-			Vector<uint8_t> data = image->get_data();
-			int dl = data.size();
-			const uint8_t *r = data.ptr();
-			f->store_buffer(r, dl);
 		} break;
 		case COMPRESS_VRAM_UNCOMPRESSED: {
 			f->store_32(CompressedTexture2D::DATA_FORMAT_IMAGE);
@@ -322,12 +327,7 @@ void ResourceImporterTexture::save_to_ctex_format(Ref<FileAccess> f, const Ref<I
 			f->store_16(p_image->get_height());
 			f->store_32(p_image->get_mipmap_count());
 			f->store_32(p_image->get_format());
-
-			Vector<uint8_t> data = p_image->get_data();
-			int dl = data.size();
-			const uint8_t *r = data.ptr();
-
-			f->store_buffer(r, dl);
+			f->store_buffer(p_image->get_data());
 
 		} break;
 		case COMPRESS_BASIS_UNIVERSAL: {
@@ -336,11 +336,12 @@ void ResourceImporterTexture::save_to_ctex_format(Ref<FileAccess> f, const Ref<I
 			f->store_16(p_image->get_height());
 			f->store_32(p_image->get_mipmap_count());
 			f->store_32(p_image->get_format());
+
 			Vector<uint8_t> data = Image::basis_universal_packer(p_image, p_channels);
-			int data_len = data.size();
-			f->store_32(data_len);
-			const uint8_t *r = data.ptr();
-			f->store_buffer(r, data_len);
+			const uint64_t data_size = data.size();
+
+			f->store_32(data_size);
+			f->store_buffer(data.ptr(), data_size);
 		} break;
 	}
 }
@@ -348,14 +349,17 @@ void ResourceImporterTexture::save_to_ctex_format(Ref<FileAccess> f, const Ref<I
 void ResourceImporterTexture::_save_ctex(const Ref<Image> &p_image, const String &p_to_path, CompressMode p_compress_mode, float p_lossy_quality, Image::CompressMode p_vram_compression, bool p_mipmaps, bool p_streamable, bool p_detect_3d, bool p_detect_roughness, bool p_detect_normal, bool p_force_normal, bool p_srgb_friendly, bool p_force_po2_for_compressed, uint32_t p_limit_mipmap, const Ref<Image> &p_normal, Image::RoughnessChannel p_roughness_channel) {
 	Ref<FileAccess> f = FileAccess::open(p_to_path, FileAccess::WRITE);
 	ERR_FAIL_COND(f.is_null());
+
+	// Godot Streamable Texture 2D.
 	f->store_8('G');
 	f->store_8('S');
 	f->store_8('T');
-	f->store_8('2'); //godot streamable texture 2D
+	f->store_8('2');
 
-	//format version
+	// Current format version.
 	f->store_32(CompressedTexture2D::FORMAT_VERSION);
-	//texture may be resized later, so original size must be saved first
+
+	// Texture may be resized later, so original size must be saved first.
 	f->store_32(p_image->get_width());
 	f->store_32(p_image->get_height());
 
@@ -364,7 +368,7 @@ void ResourceImporterTexture::_save_ctex(const Ref<Image> &p_image, const String
 		flags |= CompressedTexture2D::FORMAT_BIT_STREAM;
 	}
 	if (p_mipmaps) {
-		flags |= CompressedTexture2D::FORMAT_BIT_HAS_MIPMAPS; //mipmaps bit
+		flags |= CompressedTexture2D::FORMAT_BIT_HAS_MIPMAPS;
 	}
 	if (p_detect_3d) {
 		flags |= CompressedTexture2D::FORMAT_BIT_DETECT_3D;
@@ -378,7 +382,8 @@ void ResourceImporterTexture::_save_ctex(const Ref<Image> &p_image, const String
 
 	f->store_32(flags);
 	f->store_32(p_limit_mipmap);
-	//reserved for future use
+
+	// Reserved.
 	f->store_32(0);
 	f->store_32(0);
 	f->store_32(0);
@@ -389,30 +394,37 @@ void ResourceImporterTexture::_save_ctex(const Ref<Image> &p_image, const String
 
 	Ref<Image> image = p_image->duplicate();
 
-	if (p_force_po2_for_compressed && p_mipmaps && ((p_compress_mode == COMPRESS_BASIS_UNIVERSAL) || (p_compress_mode == COMPRESS_VRAM_COMPRESSED))) {
-		image->resize_to_po2();
-	}
+	if (p_mipmaps) {
+		if (p_force_po2_for_compressed && (p_compress_mode == COMPRESS_BASIS_UNIVERSAL || p_compress_mode == COMPRESS_VRAM_COMPRESSED)) {
+			image->resize_to_po2();
+		}
 
-	if (p_mipmaps && (!image->has_mipmaps() || p_force_normal)) {
-		image->generate_mipmaps(p_force_normal);
-	}
+		if (!image->has_mipmaps() || p_force_normal) {
+			image->generate_mipmaps(p_force_normal);
+		}
 
-	if (!p_mipmaps) {
+	} else {
 		image->clear_mipmaps();
 	}
 
+	// Generate roughness mipmaps from normal texture.
 	if (image->has_mipmaps() && p_normal.is_valid()) {
 		image->generate_mipmap_roughness(p_roughness_channel, p_normal);
 	}
 
-	Image::CompressSource csource = Image::COMPRESS_SOURCE_GENERIC;
-	if (p_force_normal) {
-		csource = Image::COMPRESS_SOURCE_NORMAL;
-	} else if (p_srgb_friendly) {
-		csource = Image::COMPRESS_SOURCE_SRGB;
-	}
+	// Optimization: Only check for color channels when compressing as BasisU or VRAM.
+	Image::UsedChannels used_channels = Image::USED_CHANNELS_RGBA;
+
+	if (p_compress_mode == COMPRESS_BASIS_UNIVERSAL || p_compress_mode == COMPRESS_VRAM_COMPRESSED) {
+		Image::CompressSource comp_source = Image::COMPRESS_SOURCE_GENERIC;
+		if (p_force_normal) {
+			comp_source = Image::COMPRESS_SOURCE_NORMAL;
+		} else if (p_srgb_friendly) {
+			comp_source = Image::COMPRESS_SOURCE_SRGB;
+		}
 
-	Image::UsedChannels used_channels = image->detect_used_channels(csource);
+		used_channels = image->detect_used_channels(comp_source);
+	}
 
 	save_to_ctex_format(f, image, p_compress_mode, used_channels, p_vram_compression, p_lossy_quality);
 }
@@ -431,6 +443,50 @@ Dictionary ResourceImporterTexture::_load_editor_meta(const String &p_path) cons
 	return f->get_var();
 }
 
+void ResourceImporterTexture::_invert_y_channel(Ref<Image> &r_image) {
+	// Inverting the green channel can be used to flip a normal map's direction.
+	// There's no standard when it comes to normal map Y direction, so this is
+	// sometimes needed when using a normal map exported from another program.
+	// See <http://wiki.polycount.com/wiki/Normal_Map_Technical_Details#Common_Swizzle_Coordinates>.
+	const int height = r_image->get_height();
+	const int width = r_image->get_width();
+
+	for (int i = 0; i < width; i++) {
+		for (int j = 0; j < height; j++) {
+			const Color color = r_image->get_pixel(i, j);
+			r_image->set_pixel(i, j, Color(color.r, 1 - color.g, color.b, color.a));
+		}
+	}
+}
+
+void ResourceImporterTexture::_clamp_hdr_exposure(Ref<Image> &r_image) {
+	// Clamp HDR exposure following Filament's tonemapping formula.
+	// This can be used to reduce fireflies in environment maps or reduce the influence
+	// of the sun from an HDRI panorama on environment lighting (when a DirectionalLight3D is used instead).
+	const int height = r_image->get_height();
+	const int width = r_image->get_width();
+
+	// These values are chosen arbitrarily and seem to produce good results with 4,096 samples.
+	const float linear = 4096.0;
+	const float compressed = 16384.0;
+
+	for (int i = 0; i < width; i++) {
+		for (int j = 0; j < height; j++) {
+			const Color color = r_image->get_pixel(i, j);
+			const float luma = color.get_luminance();
+
+			Color clamped_color;
+			if (luma <= linear) {
+				clamped_color = color;
+			} else {
+				clamped_color = (color / luma) * ((linear * linear - compressed * luma) / (2 * linear - compressed - luma));
+			}
+
+			r_image->set_pixel(i, j, clamped_color);
+		}
+	}
+}
+
 Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String &p_source_file, const String &p_save_path, const HashMap<StringName, Variant> &p_options, List<String> *r_platform_variants, List<String> *r_gen_files, Variant *r_metadata) {
 	// Parse import options.
 	int32_t loader_flags = ImageFormatLoader::FLAG_NONE;
@@ -455,10 +511,11 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 	const bool fix_alpha_border = p_options["process/fix_alpha_border"];
 	const bool premult_alpha = p_options["process/premult_alpha"];
 	const bool normal_map_invert_y = p_options["process/normal_map_invert_y"];
-	// Support for texture streaming is not implemented yet.
-	const bool stream = false;
 
+	const bool hdr_as_srgb = p_options["process/hdr_as_srgb"];
+	const bool hdr_clamp_exposure = p_options["process/hdr_clamp_exposure"];
 	int size_limit = p_options["process/size_limit"];
+
 	bool using_fallback_size_limit = false;
 	if (size_limit == 0) {
 		using_fallback_size_limit = true;
@@ -479,28 +536,27 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 		}
 	}
 
-	const bool hdr_as_srgb = p_options["process/hdr_as_srgb"];
-	if (hdr_as_srgb) {
-		loader_flags |= ImageFormatLoader::FLAG_FORCE_LINEAR;
-	}
-	const bool hdr_clamp_exposure = p_options["process/hdr_clamp_exposure"];
+	// Support for texture streaming is not implemented yet.
+	const bool stream = false;
 
-	float scale = 1.0;
 	// SVG-specific options.
-	if (p_options.has("svg/scale")) {
-		scale = p_options["svg/scale"];
-	}
+	float scale = p_options.has("svg/scale") ? float(p_options["svg/scale"]) : 1.0f;
 
 	// Editor-specific options.
 	bool use_editor_scale = p_options.has("editor/scale_with_editor_scale") && p_options["editor/scale_with_editor_scale"];
 	bool convert_editor_colors = p_options.has("editor/convert_colors_with_editor_theme") && p_options["editor/convert_colors_with_editor_theme"];
 
+	if (hdr_as_srgb) {
+		loader_flags |= ImageFormatLoader::FLAG_FORCE_LINEAR;
+	}
+
 	// Start importing images.
-	List<Ref<Image>> images_imported;
+	LocalVector<Ref<Image>> images_imported;
 
 	// Load the normal image.
 	Ref<Image> normal_image;
 	Image::RoughnessChannel roughness_channel = Image::ROUGHNESS_CHANNEL_R;
+
 	if (mipmaps && roughness > 1 && FileAccess::exists(normal_map)) {
 		normal_image.instantiate();
 		if (ImageLoader::load_image(normal_map, normal_image) == OK) {
@@ -520,11 +576,9 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 	// Load the editor-only image.
 	Ref<Image> editor_image;
 	bool import_editor_image = use_editor_scale || convert_editor_colors;
+
 	if (import_editor_image) {
-		float editor_scale = scale;
-		if (use_editor_scale) {
-			editor_scale = scale * EDSCALE;
-		}
+		float editor_scale = use_editor_scale ? scale * EDSCALE : scale;
 
 		int32_t editor_loader_flags = loader_flags;
 		if (convert_editor_colors) {
@@ -533,8 +587,9 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 
 		editor_image.instantiate();
 		err = ImageLoader::load_image(p_source_file, editor_image, nullptr, editor_loader_flags, editor_scale);
+
 		if (err != OK) {
-			WARN_PRINT("Failed to import an image resource for editor use from '" + p_source_file + "'");
+			WARN_PRINT(vformat("Failed to import an image resource for editor use from '%s'.", p_source_file));
 		} else {
 			images_imported.push_back(editor_image);
 		}
@@ -580,48 +635,12 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 
 		// Invert the green channel of the image to flip the normal map it contains.
 		if (normal_map_invert_y) {
-			// Inverting the green channel can be used to flip a normal map's direction.
-			// There's no standard when it comes to normal map Y direction, so this is
-			// sometimes needed when using a normal map exported from another program.
-			// See <http://wiki.polycount.com/wiki/Normal_Map_Technical_Details#Common_Swizzle_Coordinates>.
-			const int height = target_image->get_height();
-			const int width = target_image->get_width();
-
-			for (int i = 0; i < width; i++) {
-				for (int j = 0; j < height; j++) {
-					const Color color = target_image->get_pixel(i, j);
-					target_image->set_pixel(i, j, Color(color.r, 1 - color.g, color.b, color.a));
-				}
-			}
+			_invert_y_channel(target_image);
 		}
 
 		// Clamp HDR exposure.
 		if (hdr_clamp_exposure) {
-			// Clamp HDR exposure following Filament's tonemapping formula.
-			// This can be used to reduce fireflies in environment maps or reduce the influence
-			// of the sun from an HDRI panorama on environment lighting (when a DirectionalLight3D is used instead).
-			const int height = target_image->get_height();
-			const int width = target_image->get_width();
-
-			// These values are chosen arbitrarily and seem to produce good results with 4,096 samples.
-			const float linear = 4096.0;
-			const float compressed = 16384.0;
-
-			for (int i = 0; i < width; i++) {
-				for (int j = 0; j < height; j++) {
-					const Color color = target_image->get_pixel(i, j);
-					const float luma = color.get_luminance();
-
-					Color clamped_color;
-					if (luma <= linear) {
-						clamped_color = color;
-					} else {
-						clamped_color = (color / luma) * ((linear * linear - compressed * luma) / (2 * linear - compressed - luma));
-					}
-
-					target_image->set_pixel(i, j, clamped_color);
-				}
-			}
+			_clamp_hdr_exposure(target_image);
 		}
 	}
 
@@ -634,14 +653,12 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 	Array formats_imported;
 
 	if (compress_mode == COMPRESS_VRAM_COMPRESSED) {
-		// Must import in all formats, in order of priority (so platform choses the best supported one. IE, etc2 over etc).
-		// Android, GLES 2.x
-
+		// Must import in desktop and mobile formats in order of priority, so platform chooses the best supported one (e.g. s3tc over etc2 on desktop).
 		const bool is_hdr = (image->get_format() >= Image::FORMAT_RF && image->get_format() <= Image::FORMAT_RGBE9995);
 		const bool can_s3tc_bptc = ResourceImporterTextureSettings::should_import_s3tc_bptc();
 		const bool can_etc2_astc = ResourceImporterTextureSettings::should_import_etc2_astc();
 
-		// Add list of formats imported
+		// Add list of formats imported.
 		if (can_s3tc_bptc) {
 			formats_imported.push_back("s3tc_bptc");
 		}
@@ -651,7 +668,7 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 
 		bool can_compress_hdr = hdr_compression > 0;
 		bool has_alpha = image->detect_alpha() != Image::ALPHA_NONE;
-		bool use_uncompressed = false;
+		bool force_uncompressed = false;
 
 		if (is_hdr) {
 			if (has_alpha) {
@@ -668,17 +685,16 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 				}
 			}
 
-			if (!can_compress_hdr) {
-				// Fallback to RGBE99995.
-				if (image->get_format() != Image::FORMAT_RGBE9995) {
-					image->convert(Image::FORMAT_RGBE9995);
-					use_uncompressed = true;
-				}
+			// Fall back to RGBE99995.
+			if (!can_compress_hdr && image->get_format() != Image::FORMAT_RGBE9995) {
+				image->convert(Image::FORMAT_RGBE9995);
+				force_uncompressed = true;
 			}
 		}
 
-		if (use_uncompressed) {
-			_save_ctex(image, p_save_path + ".ctex", COMPRESS_VRAM_UNCOMPRESSED, lossy, Image::COMPRESS_S3TC /*this is ignored */, mipmaps, stream, detect_3d, detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
+		if (force_uncompressed) {
+			_save_ctex(image, p_save_path + ".ctex", COMPRESS_VRAM_UNCOMPRESSED, lossy, Image::COMPRESS_S3TC /* This is ignored. */,
+					mipmaps, stream, detect_3d, detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
 		} else {
 			if (can_s3tc_bptc) {
 				Image::CompressMode image_compress_mode;
@@ -690,7 +706,9 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 					image_compress_mode = Image::COMPRESS_S3TC;
 					image_compress_format = "s3tc";
 				}
-				_save_ctex(image, p_save_path + "." + image_compress_format + ".ctex", compress_mode, lossy, image_compress_mode, mipmaps, stream, detect_3d, detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
+
+				_save_ctex(image, p_save_path + "." + image_compress_format + ".ctex", compress_mode, lossy, image_compress_mode, mipmaps, stream, detect_3d,
+						detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
 				r_platform_variants->push_back(image_compress_format);
 			}
 
@@ -704,17 +722,21 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 					image_compress_mode = Image::COMPRESS_ETC2;
 					image_compress_format = "etc2";
 				}
-				_save_ctex(image, p_save_path + "." + image_compress_format + ".ctex", compress_mode, lossy, image_compress_mode, mipmaps, stream, detect_3d, detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
+
+				_save_ctex(image, p_save_path + "." + image_compress_format + ".ctex", compress_mode, lossy, image_compress_mode, mipmaps, stream, detect_3d,
+						detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
 				r_platform_variants->push_back(image_compress_format);
 			}
 		}
 	} else {
 		// Import normally.
-		_save_ctex(image, p_save_path + ".ctex", compress_mode, lossy, Image::COMPRESS_S3TC /*this is ignored */, mipmaps, stream, detect_3d, detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
+		_save_ctex(image, p_save_path + ".ctex", compress_mode, lossy, Image::COMPRESS_S3TC /* This is ignored. */,
+				mipmaps, stream, detect_3d, detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
 	}
 
 	if (editor_image.is_valid()) {
-		_save_ctex(editor_image, p_save_path + ".editor.ctex", compress_mode, lossy, Image::COMPRESS_S3TC /*this is ignored */, mipmaps, stream, detect_3d, detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
+		_save_ctex(editor_image, p_save_path + ".editor.ctex", compress_mode, lossy, Image::COMPRESS_S3TC /* This is ignored. */,
+				mipmaps, stream, detect_3d, detect_roughness, detect_normal, force_normal, srgb_friendly_pack, false, mipmap_limit, normal_image, roughness_channel);
 
 		// Generate and save editor-specific metadata, which we cannot save to the .import file.
 		Dictionary editor_meta;
@@ -722,6 +744,7 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 		if (use_editor_scale) {
 			editor_meta["editor_scale"] = EDSCALE;
 		}
+
 		if (convert_editor_colors) {
 			editor_meta["editor_dark_theme"] = EditorThemeManager::is_dark_theme();
 		}
@@ -732,6 +755,7 @@ Error ResourceImporterTexture::import(ResourceUID::ID p_source_id, const String
 	if (r_metadata) {
 		Dictionary meta;
 		meta["vram_texture"] = compress_mode == COMPRESS_VRAM_COMPRESSED;
+
 		if (formats_imported.size()) {
 			meta["imported_formats"] = formats_imported;
 		}
@@ -751,16 +775,17 @@ const char *ResourceImporterTexture::compression_formats[] = {
 	"etc2_astc",
 	nullptr
 };
+
 String ResourceImporterTexture::get_import_settings_string() const {
 	String s;
 
 	int index = 0;
 	while (compression_formats[index]) {
-		String setting_path = "rendering/textures/vram_compression/import_" + String(compression_formats[index]);
-		bool test = GLOBAL_GET(setting_path);
-		if (test) {
+		const String setting_path = "rendering/textures/vram_compression/import_" + String(compression_formats[index]);
+		if (bool(GLOBAL_GET(setting_path))) {
 			s += String(compression_formats[index]);
 		}
+
 		index++;
 	}
 
@@ -780,6 +805,7 @@ bool ResourceImporterTexture::are_import_settings_valid(const String &p_path, co
 		if (editor_meta.has("editor_scale") && (float)editor_meta["editor_scale"] != EDSCALE) {
 			return false;
 		}
+
 		if (editor_meta.has("editor_dark_theme") && (bool)editor_meta["editor_dark_theme"] != EditorThemeManager::is_dark_theme()) {
 			return false;
 		}
@@ -789,8 +815,7 @@ bool ResourceImporterTexture::are_import_settings_valid(const String &p_path, co
 		return false;
 	}
 
-	bool vram = p_meta["vram_texture"];
-	if (!vram) {
+	if (!bool(p_meta["vram_texture"])) {
 		return true; // Do not care about non-VRAM.
 	}
 
@@ -803,18 +828,16 @@ bool ResourceImporterTexture::are_import_settings_valid(const String &p_path, co
 	int index = 0;
 	bool valid = true;
 	while (compression_formats[index]) {
-		String setting_path = "rendering/textures/vram_compression/import_" + String(compression_formats[index]);
+		const String setting_path = "rendering/textures/vram_compression/import_" + String(compression_formats[index]);
 		if (ProjectSettings::get_singleton()->has_setting(setting_path)) {
-			bool test = GLOBAL_GET(setting_path);
-			if (test) {
-				if (!formats_imported.has(compression_formats[index])) {
-					valid = false;
-					break;
-				}
+			if (bool(GLOBAL_GET(setting_path)) && !formats_imported.has(compression_formats[index])) {
+				valid = false;
+				break;
 			}
 		} else {
 			WARN_PRINT("Setting for imported format not found: " + setting_path);
 		}
+
 		index++;
 	}
 

editor/import/resource_importer_texture.h

@@ -78,6 +78,10 @@ protected:
 	void _save_editor_meta(const Dictionary &p_metadata, const String &p_to_path);
 	Dictionary _load_editor_meta(const String &p_to_path) const;
 
+	static inline void _clamp_hdr_exposure(Ref<Image> &r_image);
+	static inline void _invert_y_channel(Ref<Image> &r_image);
+	static inline void _print_callback_message(const String &p_message);
+
 public:
 	static void save_to_ctex_format(Ref<FileAccess> f, const Ref<Image> &p_image, CompressMode p_compress_mode, Image::UsedChannels p_channels, Image::CompressMode p_compress_format, float p_lossy_quality);