X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fgraphics%2Fpng%2Fpngloader.cpp;h=9c2e1ae339213c2f3cc5a2ad5965ecebb759bf33;hb=479298192e3e5b71a402f79520c90372a4c4b504;hp=3f2f95912da05dd068075064edca261b47f521ee;hpb=8e403dbbcde6efee1862f6d501ce30a3e7ba81c4;p=libs%2Fgui.git

diff --git a/source/graphics/png/pngloader.cpp b/source/graphics/png/pngloader.cpp
index 3f2f959..9c2e1ae 100644
--- a/source/graphics/png/pngloader.cpp
+++ b/source/graphics/png/pngloader.cpp
@@ -1,5 +1,5 @@
-#include <png.h>
 #include "pngloader.h"
+#include <png.h>
 
 using namespace std;
 
@@ -26,15 +26,17 @@ namespace Graphics {
 
 struct PngLoader::Private
 {
-	std::string message;
-	png_struct *png;
-	png_info *info;
+	string message;
+	png_struct *png = nullptr;
+	png_info *info = nullptr;
+	int interlace = PNG_INTERLACE_NONE;
 };
 
+
 PngLoader::PngLoader(IO::Base &io, unsigned sig_bytes):
 	priv(new Private)
 {
-	priv->png = png_create_read_struct(PNG_LIBPNG_VER_STRING, &priv->message, error, 0);
+	priv->png = png_create_read_struct(PNG_LIBPNG_VER_STRING, &priv->message, error, nullptr);
 	priv->info = png_create_info_struct(priv->png);
 
 	// These probably won't give any errors
@@ -44,50 +46,78 @@ PngLoader::PngLoader(IO::Base &io, unsigned sig_bytes):
 
 PngLoader::~PngLoader()
 {
-	png_destroy_read_struct(&priv->png, &priv->info, 0);
+	png_destroy_read_struct(&priv->png, &priv->info, nullptr);
 	delete priv;
 }
 
-bool PngLoader::detect(const std::string &sig)
+bool PngLoader::detect(const string &sig)
 {
 	return !png_sig_cmp(reinterpret_cast<png_byte *>(const_cast<char*>(sig.data())), 0, sig.size());
 }
 
-void PngLoader::load(Image::Data &data)
+void PngLoader::load_headers_(Image::Data &data)
 {
 	if(setjmp(png_jmpbuf(priv->png)))
+	{
 		throw bad_image_data(priv->message);
+	}
 
 	png_read_info(priv->png, priv->info);
 	png_uint_32 width;
 	png_uint_32 height;
 	int depth;
 	int color;
-	png_get_IHDR(priv->png, priv->info, &width, &height, &depth, &color, 0, 0, 0);
-	data.width = width;
-	data.height = height;
+	png_get_IHDR(priv->png, priv->info, &width, &height, &depth, &color, &priv->interlace, nullptr, nullptr);
+	unsigned nchans = png_get_channels(priv->png, priv->info);
+
 	if(depth!=8)
 		throw unsupported_image_format("depth!=8");
+
+	data.width = width;
+	data.height = height;
+	data.stride = data.width*nchans;
+
 	switch(color)
 	{
 	case PNG_COLOR_TYPE_PALETTE:    data.fmt = COLOR_INDEX; break;
 	case PNG_COLOR_TYPE_GRAY:       data.fmt = LUMINANCE; break;
 	case PNG_COLOR_TYPE_GRAY_ALPHA: data.fmt = LUMINANCE_ALPHA; break;
-	case PNG_COLOR_TYPE_RGB:        data.fmt = RGB; break;
+	case PNG_COLOR_TYPE_RGB:        data.fmt = (nchans==4 ? RGBX : RGB); break;
 	case PNG_COLOR_TYPE_RGB_ALPHA:  data.fmt = RGBA; break;
 	default: throw unsupported_image_format("unknown color type");
 	}
+}
 
-	unsigned nchans = png_get_channels(priv->png, priv->info);
-	if(nchans==4 && data.fmt==RGB)
-		png_set_strip_alpha(priv->png);
+void PngLoader::load_pixels_(Image::Data &data)
+{
+	png_byte **rows = nullptr;
+
+	if(setjmp(png_jmpbuf(priv->png)))
+	{
+		delete[] rows;
+		throw bad_image_data(priv->message);
+	}
 
-	unsigned rowstride = data.width*nchans;
-	data.data = new char[rowstride*data.height];
-	for(unsigned y=0; y<data.height; ++y)
-		png_read_row(priv->png, reinterpret_cast<png_byte *>(data.data+rowstride*(data.height-1-y)), 0);
+	if(priv->interlace==PNG_INTERLACE_ADAM7)
+	{
+		// ADAM7 requires all rows to be loaded at once
+		unsigned n_passes = png_set_interlace_handling(priv->png);
+		rows = new png_byte *[data.height];
+		for(unsigned y=0; y<data.height; ++y)
+			rows[y] = reinterpret_cast<png_byte *>(data.pixels+data.stride*(data.height-1-y));
+
+		for(unsigned i=0; i<n_passes; ++i)
+			png_read_rows(priv->png, rows, nullptr, data.height);
+
+		delete[] rows;
+	}
+	else
+	{
+		for(unsigned y=0; y<data.height; ++y)
+			png_read_row(priv->png, reinterpret_cast<png_byte *>(data.pixels+data.stride*(data.height-1-y)), nullptr);
+	}
 
-	png_read_end(priv->png, 0);
+	png_read_end(priv->png, nullptr);
 }
 
 } // namespace Graphics