Merge pull request #29874 from ibrahn/rework-png-loadsave

PNG driver reworked to use libpng 1.6 simplified API

1 files changed, 35 insertions, 320 deletions

diff --git a/drivers/png/image_loader_png.cpp b/drivers/png/image_loader_png.cpp
index 0bf432c78a..f257fafd93 100644
--- a/drivers/png/image_loader_png.cpp
+++ b/drivers/png/image_loader_png.cpp
@@ -32,186 +32,26 @@
 
 #include "core/os/os.h"
 #include "core/print_string.h"
+#include "drivers/png/png_driver_common.h"
 
 #include <string.h>
 
-void ImageLoaderPNG::_read_png_data(png_structp png_ptr, png_bytep data, png_size_t p_length) {
-
-	FileAccess *f = (FileAccess *)png_get_io_ptr(png_ptr);
-	f->get_buffer((uint8_t *)data, p_length);
-}
-
-/*
-png_structp png_ptr = png_create_read_struct_2
-    (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
-     user_error_fn, user_warning_fn, (png_voidp)
-     user_mem_ptr, user_malloc_fn, user_free_fn);
-*/
-static png_voidp _png_malloc_fn(png_structp png_ptr, png_size_t size) {
-
-	return memalloc(size);
-}
-
-static void _png_free_fn(png_structp png_ptr, png_voidp ptr) {
-
-	memfree(ptr);
-}
-
-static void _png_error_function(png_structp, png_const_charp text) {
-
-	ERR_PRINT(text);
-}
-
-static void _png_warn_function(png_structp, png_const_charp text) {
-#ifdef TOOLS_ENABLED
-	if (Engine::get_singleton()->is_editor_hint()) {
-		if (String(text).begins_with("iCCP")) return; // silences annoying spam emitted to output every time the user opened assetlib
-	}
-#endif
-	WARN_PRINT(text);
-}
-
-typedef void(PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
-
-Error ImageLoaderPNG::_load_image(void *rf_up, png_rw_ptr p_func, Ref<Image> p_image) {
-
-	png_structp png;
-	png_infop info;
-
-	//png = png_create_read_struct(PNG_LIBPNG_VER_STRING, (png_voidp)NULL, NULL, NULL);
-
-	png = png_create_read_struct_2(PNG_LIBPNG_VER_STRING, (png_voidp)NULL, _png_error_function, _png_warn_function, (png_voidp)NULL,
-			_png_malloc_fn, _png_free_fn);
-
-	ERR_FAIL_COND_V(!png, ERR_OUT_OF_MEMORY);
-
-	info = png_create_info_struct(png);
-	if (!info) {
-		png_destroy_read_struct(&png, NULL, NULL);
-		ERR_PRINT("Out of Memory");
-		return ERR_OUT_OF_MEMORY;
-	}
-
-	if (setjmp(png_jmpbuf(png))) {
-
-		png_destroy_read_struct(&png, NULL, NULL);
-		ERR_PRINT("PNG Corrupted");
-		return ERR_FILE_CORRUPT;
-	}
-
-	png_set_read_fn(png, (void *)rf_up, p_func);
-
-	png_uint_32 width, height;
-	int depth, color;
-
-	png_read_info(png, info);
-	png_get_IHDR(png, info, &width, &height, &depth, &color, NULL, NULL, NULL);
-
-	//https://svn.gov.pt/projects/ccidadao/repository/middleware-offline/trunk/_src/eidmw/FreeImagePTEiD/Source/FreeImage/PluginPNG.cpp
-	//png_get_text(png,info,)
-	/*
-	printf("Image width:%i\n", width);
-	printf("Image Height:%i\n", height);
-	printf("Bit depth:%i\n", depth);
-	printf("Color type:%i\n", color);
-	*/
-
-	bool update_info = false;
-
-	if (depth < 8) { //only bit dept 8 per channel is handled
-
-		png_set_packing(png);
-		update_info = true;
-	};
-
-	if (png_get_color_type(png, info) == PNG_COLOR_TYPE_PALETTE) {
-		png_set_palette_to_rgb(png);
-		update_info = true;
-	}
-
-	if (depth > 8) {
-		png_set_strip_16(png);
-		update_info = true;
-	}
-
-	if (png_get_valid(png, info, PNG_INFO_tRNS)) {
-		//png_set_expand_gray_1_2_4_to_8(png);
-		png_set_tRNS_to_alpha(png);
-		update_info = true;
-	}
-
-	if (update_info) {
-		png_read_update_info(png, info);
-		png_get_IHDR(png, info, &width, &height, &depth, &color, NULL, NULL, NULL);
-	}
-
-	int components = 0;
-
-	Image::Format fmt;
-	switch (color) {
-
-		case PNG_COLOR_TYPE_GRAY: {
-
-			fmt = Image::FORMAT_L8;
-			components = 1;
-		} break;
-		case PNG_COLOR_TYPE_GRAY_ALPHA: {
-
-			fmt = Image::FORMAT_LA8;
-			components = 2;
-		} break;
-		case PNG_COLOR_TYPE_RGB: {
-
-			fmt = Image::FORMAT_RGB8;
-			components = 3;
-		} break;
-		case PNG_COLOR_TYPE_RGB_ALPHA: {
-
-			fmt = Image::FORMAT_RGBA8;
-			components = 4;
-		} break;
-		default: {
+Error ImageLoaderPNG::load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale) {
 
-			ERR_PRINT("INVALID PNG TYPE");
-			png_destroy_read_struct(&png, &info, NULL);
-			return ERR_UNAVAILABLE;
-		} break;
+	const size_t buffer_size = f->get_len();
+	PoolVector<uint8_t> file_buffer;
+	Error err = file_buffer.resize(buffer_size);
+	if (err) {
+		f->close();
+		return err;
 	}
-
-	//int rowsize = png_get_rowbytes(png, info);
-	int rowsize = components * width;
-
-	PoolVector<uint8_t> dstbuff;
-
-	dstbuff.resize(rowsize * height);
-
-	PoolVector<uint8_t>::Write dstbuff_write = dstbuff.write();
-
-	uint8_t *data = dstbuff_write.ptr();
-
-	uint8_t **row_p = memnew_arr(uint8_t *, height);
-
-	for (unsigned int i = 0; i < height; i++) {
-		row_p[i] = &data[components * width * i];
+	{
+		PoolVector<uint8_t>::Write writer = file_buffer.write();
+		f->get_buffer(writer.ptr(), buffer_size);
+		f->close();
 	}
-
-	png_read_image(png, (png_bytep *)row_p);
-
-	memdelete_arr(row_p);
-
-	p_image->create(width, height, 0, fmt, dstbuff);
-
-	png_destroy_read_struct(&png, &info, NULL);
-
-	return OK;
-}
-
-Error ImageLoaderPNG::load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale) {
-
-	Error err = _load_image(f, _read_png_data, p_image);
-	f->close();
-
-	return err;
+	PoolVector<uint8_t>::Read reader = file_buffer.read();
+	return PNGDriverCommon::png_to_image(reader.ptr(), buffer_size, p_image);
 }
 
 void ImageLoaderPNG::get_recognized_extensions(List<String> *p_extensions) const {
@@ -219,178 +59,53 @@ void ImageLoaderPNG::get_recognized_extensions(List<String> *p_extensions) const
 	p_extensions->push_back("png");
 }
 
-struct PNGReadStatus {
-
-	uint32_t offset;
-	uint32_t size;
-	const unsigned char *image;
-};
-
-static void user_read_data(png_structp png_ptr, png_bytep data, png_size_t p_length) {
-
-	PNGReadStatus *rstatus;
-	rstatus = (PNGReadStatus *)png_get_io_ptr(png_ptr);
-
-	png_size_t to_read = MIN(p_length, rstatus->size - rstatus->offset);
-	memcpy(data, &rstatus->image[rstatus->offset], to_read);
-	rstatus->offset += to_read;
-
-	if (to_read < p_length) {
-		memset(&data[to_read], 0, p_length - to_read);
-	}
-}
-
-static Ref<Image> _load_mem_png(const uint8_t *p_png, int p_size) {
-
-	PNGReadStatus prs;
-	prs.image = p_png;
-	prs.offset = 0;
-	prs.size = p_size;
+Ref<Image> ImageLoaderPNG::load_mem_png(const uint8_t *p_png, int p_size) {
 
 	Ref<Image> img;
 	img.instance();
-	Error err = ImageLoaderPNG::_load_image(&prs, user_read_data, img);
+
+	Error err = PNGDriverCommon::png_to_image(p_png, p_size, img);
 	ERR_FAIL_COND_V(err, Ref<Image>());
 
 	return img;
 }
 
-static Ref<Image> _lossless_unpack_png(const PoolVector<uint8_t> &p_data) {
+Ref<Image> ImageLoaderPNG::lossless_unpack_png(const PoolVector<uint8_t> &p_data) {
 
-	int len = p_data.size();
+	const int len = p_data.size();
 	ERR_FAIL_COND_V(len < 4, Ref<Image>());
 	PoolVector<uint8_t>::Read r = p_data.read();
 	ERR_FAIL_COND_V(r[0] != 'P' || r[1] != 'N' || r[2] != 'G' || r[3] != ' ', Ref<Image>());
-	return _load_mem_png(&r[4], len - 4);
-}
-
-static void _write_png_data(png_structp png_ptr, png_bytep data, png_size_t p_length) {
-
-	PoolVector<uint8_t> &v = *(PoolVector<uint8_t> *)png_get_io_ptr(png_ptr);
-	int vs = v.size();
-
-	v.resize(vs + p_length);
-	PoolVector<uint8_t>::Write w = v.write();
-	copymem(&w[vs], data, p_length);
+	return load_mem_png(&r[4], len - 4);
 }
 
-static PoolVector<uint8_t> _lossless_pack_png(const Ref<Image> &p_image) {
-
-	Ref<Image> img = p_image->duplicate();
-
-	if (img->is_compressed())
-		img->decompress();
-
-	ERR_FAIL_COND_V(img->is_compressed(), PoolVector<uint8_t>());
-
-	png_structp png_ptr;
-	png_infop info_ptr;
-	png_bytep *row_pointers;
-
-	/* initialize stuff */
-	png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+PoolVector<uint8_t> ImageLoaderPNG::lossless_pack_png(const Ref<Image> &p_image) {
 
-	ERR_FAIL_COND_V(!png_ptr, PoolVector<uint8_t>());
+	PoolVector<uint8_t> out_buffer;
 
-	info_ptr = png_create_info_struct(png_ptr);
-
-	ERR_FAIL_COND_V(!info_ptr, PoolVector<uint8_t>());
-
-	if (setjmp(png_jmpbuf(png_ptr))) {
+	// add Godot's own "PNG " prefix
+	if (out_buffer.resize(4) != OK) {
 		ERR_FAIL_V(PoolVector<uint8_t>());
 	}
-	PoolVector<uint8_t> ret;
-	ret.push_back('P');
-	ret.push_back('N');
-	ret.push_back('G');
-	ret.push_back(' ');
 
-	png_set_write_fn(png_ptr, &ret, _write_png_data, NULL);
-
-	/* write header */
-	if (setjmp(png_jmpbuf(png_ptr))) {
-		ERR_FAIL_V(PoolVector<uint8_t>());
+	// scope for writer lifetime
+	{
+		// must be closed before call to image_to_png
+		PoolVector<uint8_t>::Write writer = out_buffer.write();
+		copymem(writer.ptr(), "PNG ", 4);
 	}
 
-	int pngf = 0;
-	int cs = 0;
-
-	switch (img->get_format()) {
-
-		case Image::FORMAT_L8: {
-
-			pngf = PNG_COLOR_TYPE_GRAY;
-			cs = 1;
-		} break;
-		case Image::FORMAT_LA8: {
-
-			pngf = PNG_COLOR_TYPE_GRAY_ALPHA;
-			cs = 2;
-		} break;
-		case Image::FORMAT_RGB8: {
-
-			pngf = PNG_COLOR_TYPE_RGB;
-			cs = 3;
-		} break;
-		case Image::FORMAT_RGBA8: {
-
-			pngf = PNG_COLOR_TYPE_RGB_ALPHA;
-			cs = 4;
-		} break;
-		default: {
-
-			if (img->detect_alpha()) {
-
-				img->convert(Image::FORMAT_RGBA8);
-				pngf = PNG_COLOR_TYPE_RGB_ALPHA;
-				cs = 4;
-			} else {
-
-				img->convert(Image::FORMAT_RGB8);
-				pngf = PNG_COLOR_TYPE_RGB;
-				cs = 3;
-			}
-		}
-	}
-
-	int w = img->get_width();
-	int h = img->get_height();
-	png_set_IHDR(png_ptr, info_ptr, w, h,
-			8, pngf, PNG_INTERLACE_NONE,
-			PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
-
-	png_write_info(png_ptr, info_ptr);
-
-	/* write bytes */
-	if (setjmp(png_jmpbuf(png_ptr))) {
+	Error err = PNGDriverCommon::image_to_png(p_image, out_buffer);
+	if (err) {
 		ERR_FAIL_V(PoolVector<uint8_t>());
 	}
 
-	PoolVector<uint8_t>::Read r = img->get_data().read();
-
-	row_pointers = (png_bytep *)memalloc(sizeof(png_bytep) * h);
-	for (int i = 0; i < h; i++) {
-
-		row_pointers[i] = (png_bytep)&r[i * w * cs];
-	}
-	png_write_image(png_ptr, row_pointers);
-
-	memfree(row_pointers);
-
-	/* end write */
-	if (setjmp(png_jmpbuf(png_ptr))) {
-
-		ERR_FAIL_V(PoolVector<uint8_t>());
-	}
-
-	png_write_end(png_ptr, NULL);
-
-	return ret;
+	return out_buffer;
 }
 
 ImageLoaderPNG::ImageLoaderPNG() {
 
-	Image::_png_mem_loader_func = _load_mem_png;
-	Image::lossless_unpacker = _lossless_unpack_png;
-	Image::lossless_packer = _lossless_pack_png;
+	Image::_png_mem_loader_func = load_mem_png;
+	Image::lossless_unpacker = lossless_unpack_png;
+	Image::lossless_packer = lossless_pack_png;
 }