1 files changed, 187 insertions, 0 deletions
diff --git a/backends/platform/psp/png_loader.cpp b/backends/platform/psp/png_loader.cpp
new file mode 100644
index 0000000000..417c502e54
--- /dev/null
+++ b/backends/platform/psp/png_loader.cpp
@@ -0,0 +1,187 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * $URL$
+ * $Id$
+ *
+ */
+
+#include "common/scummsys.h"
+#include "common/stream.h"
+#include "backends/platform/psp/psppixelformat.h"
+#include "backends/platform/psp/display_client.h"
+#include "backends/platform/psp/png_loader.h"
+
+PngLoader::Status PngLoader::allocate() {
+	if (!findImageDimensions()) {
+		PSP_ERROR("failed to get image dimensions\n");
+		return BAD_FILE;
+	}	
+
+	PSP_DEBUG_PRINT("width[%d], height[%d], paletteSize[%d], bitDepth[%d]\n", _width, _height, _paletteSize, _bitDepth);
+	_buffer->setSize(_width, _height, _sizeBy);
+
+	if (_paletteSize) {	// 8 or 4-bit image
+		if (_paletteSize <= 16) { 					// 4 bit
+			_buffer->setPixelFormat(PSPPixelFormat::Type_Palette_4bit);
+			_palette->setPixelFormats(PSPPixelFormat::Type_4444, PSPPixelFormat::Type_Palette_4bit);
+			_paletteSize = 16;
+		} else if (_paletteSize <= 256) {			// 8-bit image
+			_paletteSize = 256;
+			_buffer->setPixelFormat(PSPPixelFormat::Type_Palette_8bit);
+			_palette->setPixelFormats(PSPPixelFormat::Type_4444, PSPPixelFormat::Type_Palette_8bit);
+		} else {
+			PSP_ERROR("palette of %d too big!\n", _paletteSize);
+			return BAD_FILE;
+		}
+
+	} else {	// 32-bit image
+		_buffer->setPixelFormat(PSPPixelFormat::Type_8888);
+	}
+
+	if (!_buffer->allocate()) {
+		PSP_ERROR("failed to allocate buffer\n");
+		return OUT_OF_MEMORY;
+	}
+	if (!_palette->allocate()) {
+		PSP_ERROR("failed to allocate palette\n");
+		return OUT_OF_MEMORY;
+	}
+	return OK;
+}	
+
+bool PngLoader::load() {
+	// Try to load the image
+	_file->seek(0);	// Go back to start
+
+	if (!loadImageIntoBuffer()) {
+		PSP_DEBUG_PRINT("failed to load image\n");
+		return false;
+	} 
+	
+	PSP_DEBUG_PRINT("succeded in loading image\n");
+
+	if (_paletteSize == 16)		// 4-bit
+		_buffer->flipNibbles();	// required because of PNG 4-bit format
+	return true;
+}
+
+void PngLoader::warningFn(png_structp png_ptr, png_const_charp warning_msg) {
+	// ignore PNG warnings
+}
+
+// Read function for png library to be able to read from our SeekableReadStream
+//
+void PngLoader::libReadFunc(png_structp pngPtr, png_bytep data, png_size_t length) {
+	Common::SeekableReadStream *file;
+
+	file = (Common::SeekableReadStream *)pngPtr->io_ptr;
+
+	file->read(data, length);
+}
+
+bool PngLoader::basicImageLoad() {
+	_pngPtr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+	if (!_pngPtr) 
+		return false;
+		
+	png_set_error_fn(_pngPtr, (png_voidp) NULL, (png_error_ptr) NULL, warningFn);
+	
+	_infoPtr = png_create_info_struct(_pngPtr);
+	if (!_infoPtr) {
+		png_destroy_read_struct(&_pngPtr, png_infopp_NULL, png_infopp_NULL);
+		return false;
+	}
+	// Set the png lib to use our read function
+	png_set_read_fn(_pngPtr, (void *)_file, libReadFunc);
+
+	unsigned int sig_read = 0;
+	
+	png_set_sig_bytes(_pngPtr, sig_read);
+	png_read_info(_pngPtr, _infoPtr);
+	int interlaceType;
+	png_get_IHDR(_pngPtr, _infoPtr, (png_uint_32 *)&_width, (png_uint_32 *)&_height, &_bitDepth, 
+		&_colorType, &interlaceType, int_p_NULL, int_p_NULL);
+
+	if (_colorType & PNG_COLOR_MASK_PALETTE)
+		_paletteSize = _infoPtr->num_palette;
+		
+	return true;
+}
+
+/* Get the width and height of a png image */
+bool PngLoader::findImageDimensions() {
+	DEBUG_ENTER_FUNC();
+
+	if (!basicImageLoad())
+		return false;
+	
+	png_destroy_read_struct(&_pngPtr, &_infoPtr, png_infopp_NULL);
+	return true;
+}
+
+//
+// Load a texture from a png image
+//
+bool PngLoader::loadImageIntoBuffer() {
+	DEBUG_ENTER_FUNC();
+
+	if (!basicImageLoad())
+		return false;
+	
+	// Strip off 16 bit channels. Not really needed but whatever
+	png_set_strip_16(_pngPtr);
+
+	if (_paletteSize) {
+		// Copy the palette
+		png_colorp srcPal = _infoPtr->palette;
+		for (int i = 0; i < (int)_paletteSize; i++) {
+			unsigned char alphaVal = (i < _infoPtr->num_trans) ? _infoPtr->trans[i] : 0xFF;	// Load alpha if it's there
+			_palette->setSingleColorRGBA(i, srcPal->red, srcPal->green, srcPal->blue, alphaVal);
+			srcPal++;
+		}
+	} else {	// Not a palettized image
+		if (_colorType == PNG_COLOR_TYPE_GRAY && _bitDepth < 8) 
+			png_set_gray_1_2_4_to_8(_pngPtr);	// Round up grayscale images
+		if (png_get_valid(_pngPtr, _infoPtr, PNG_INFO_tRNS)) 
+			png_set_tRNS_to_alpha(_pngPtr);		// Convert trans channel to alpha for 32 bits
+		
+		png_set_filler(_pngPtr, 0xff, PNG_FILLER_AFTER);	// Filler for alpha?
+	}
+
+	unsigned char *line = (unsigned char*) malloc(_infoPtr->rowbytes);
+	if (!line) {
+		png_destroy_read_struct(&_pngPtr, png_infopp_NULL, png_infopp_NULL);
+		PSP_ERROR("Couldn't allocate line\n");
+		return false;
+	}
+	
+	for (size_t y = 0; y < _height; y++) {
+		png_read_row(_pngPtr, line, png_bytep_NULL);
+		_buffer->copyFromRect(line, _infoPtr->rowbytes, 0, y, _width, 1);	// Copy into buffer
+	}
+
+	free(line);
+
+	png_read_end(_pngPtr, _infoPtr);
+	png_destroy_read_struct(&_pngPtr, &_infoPtr, png_infopp_NULL);
+
+	return true;
+}