Method load_image_from_fileV3

compat/texture_loader_compat.cpp:275–429

}

Error TextureLoaderCompat::load_image_from_fileV3(Ref<FileAccess> f, int tw, int th, int tw_custom, int th_custom, int flags, int p_size_limit, uint32_t df, Ref<Image> &image) {
	Image::Format format;
	if (!(df & FORMAT_BIT_STREAM)) {
		// do something??
	}
	if (df & FORMAT_BIT_PNG || df & FORMAT_BIT_WEBP) {
		//look for a PNG or WEBP file inside

		int sw = tw;
		int sh = th;

		uint32_t mipmaps = f->get_32();
		uint32_t size = f->get_32();

		//print_line("mipmaps: " + itos(mipmaps));

		// This is dead code; p_size_limit is always 0, and Godot 3.x never uses it
		while (mipmaps > 1 && p_size_limit > 0 && (sw > p_size_limit || sh > p_size_limit)) {
			f->seek(f->get_position() + size);
			mipmaps = f->get_32();
			size = f->get_32();

			sw = MAX(sw >> 1, 1);
			sh = MAX(sh >> 1, 1);
			mipmaps--;
		}

		// mipmaps need to be read independently, they will be later combined
		Vector<Ref<Image>> mipmap_images;
		int total_size = 0;

		for (uint32_t i = 0; i < mipmaps; i++) {
			if (i) {
				size = f->get_32();
			}
			if (size == 0) {
				ERR_FAIL_V_MSG(ERR_FILE_EOF, "Texture is empty");
			}
			Vector<uint8_t> pv;
			pv.resize(size);
			{
				uint8_t *wr = pv.ptrw();
				f->get_buffer(wr, size);
			}

			Ref<Image> img;
			if (df & FORMAT_BIT_PNG) {
				img = Image::png_unpacker(pv);
			} else {
				img = WebPCompat::webp_unpack_v2v3(pv);
			}
			ERR_FAIL_COND_V_MSG(img.is_null() || img->is_empty(), ERR_FILE_CORRUPT, "File is corrupt");

			if (i != 0) {
				img->convert(mipmap_images[0]->get_format()); // ensure the same format for all mipmaps
			}

			total_size += img->get_data().size();