text: /*************************************************************************/
  /*  resource_saver_png.cpp                                               */
  /*************************************************************************/
  /*                       This file is part of:                           */
  /*                           GODOT ENGINE                                */
  /*                      https://godotengine.org                          */
  /*************************************************************************/
  /* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
  /* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
  /*                                                                       */
  /* Permission is hereby granted, free of charge, to any person obtaining */
  /* a copy of this software and associated documentation files (the       */
  /* "Software"), to deal in the Software without restriction, including   */
  /* without limitation the rights to use, copy, modify, merge, publish,   */
  /* distribute, sublicense, and/or sell copies of the Software, and to    */
  /* permit persons to whom the Software is furnished to do so, subject to */
  /* the following conditions:                                             */
  /*                                                                       */
  /* The above copyright notice and this permission notice shall be        */
  /* included in all copies or substantial portions of the Software.       */
  /*                                                                       */
  /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
  /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
  /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
  /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
  /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
  /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
  /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
  /*************************************************************************/
  
  #include "resource_saver_png.h"
  
  #include "core/image.h"
  #include "core/os/file_access.h"
  #include "drivers/png/png_driver_common.h"
  #include "scene/resources/texture.h"
  
  Error ResourceSaverPNG::save(const String &p_path, const RES &p_resource, uint32_t p_flags) {
  	Ref<ImageTexture> texture = p_resource;
  
  	ERR_FAIL_COND_V_MSG(!texture.is_valid(), ERR_INVALID_PARAMETER, "Can't save invalid texture as PNG.");
  	ERR_FAIL_COND_V_MSG(!texture->get_width(), ERR_INVALID_PARAMETER, "Can't save empty texture as PNG.");
  
  	Ref<Image> img = texture->get_data();
  
  	Error err = save_image(p_path, img);
  
  	return err;
  };
  
  Error ResourceSaverPNG::save_image(const String &p_path, const Ref<Image> &p_img) {
  	PoolVector<uint8_t> buffer;
  	Error err = PNGDriverCommon::image_to_png(p_img, buffer);
  	ERR_FAIL_COND_V_MSG(err, err, "Can't convert image to PNG.");
  	FileAccess *file = FileAccess::open(p_path, FileAccess::WRITE, &err);
  	ERR_FAIL_COND_V_MSG(err, err, vformat("Can't save PNG at path: '%s'.", p_path));
  
  	PoolVector<uint8_t>::Read reader = buffer.read();
  
  	file->store_buffer(reader.ptr(), buffer.size());
  	if (file->get_error() != OK && file->get_error() != ERR_FILE_EOF) {
  		memdelete(file);
  		return ERR_CANT_CREATE;
  	}
  
  	file->close();
  	memdelete(file);
  
  	return OK;
  }
  
  PoolVector<uint8_t> ResourceSaverPNG::save_image_to_buffer(const Ref<Image> &p_img) {
  	PoolVector<uint8_t> buffer;
  	Error err = PNGDriverCommon::image_to_png(p_img, buffer);
  	ERR_FAIL_COND_V_MSG(err, PoolVector<uint8_t>(), "Can't convert image to PNG.");
  	return buffer;
  }
  
  bool ResourceSaverPNG::recognize(const RES &p_resource) const {
  	return (p_resource.is_valid() && p_resource->is_class("ImageTexture"));
  }
  
  void ResourceSaverPNG::get_recognized_extensions(const RES &p_resource, List<String> *p_extensions) const {
  	if (Object::cast_to<ImageTexture>(*p_resource)) {
  		p_extensions->push_back("png");
  	}
  }
  
  ResourceSaverPNG::ResourceSaverPNG() {
  	Image::save_png_func = &save_image;
  	Image::save_png_buffer_func = &save_image_to_buffer;
  };
  