1 files changed, 113 insertions, 0 deletions
diff --git a/src/utils/pnglib.cpp b/src/utils/pnglib.cpp
new file mode 100644
index 000000000..d472bd565
--- /dev/null
+++ b/src/utils/pnglib.cpp
@@ -0,0 +1,113 @@
+/*
+ *  The ManaPlus Client
+ *  Copyright (C) 2004-2009  The Mana World Development Team
+ *  Copyright (C) 2009-2010  The Mana Developers
+ *  Copyright (C) 2011-2017  The ManaPlus Developers
+ *
+ *  This file is part of The ManaPlus Client.
+ *
+ *  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
+ *  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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "utils/pnglib.h"
+
+#include "utils/cast.h"
+#include "utils/checkutils.h"
+
+#include <png.h>
+PRAGMA48(GCC diagnostic push)
+PRAGMA48(GCC diagnostic ignored "-Wshadow")
+#include <SDL_video.h>
+PRAGMA48(GCC diagnostic pop)
+
+#include "debug.h"
+
+bool PngLib::writePNG(SDL_Surface *const surface,
+                      const std::string &filename)
+{
+    if (surface == nullptr)
+        return false;
+
+
+    if (SDL_MUSTLOCK(surface))
+        SDL_LockSurface(surface);
+
+    png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
+        nullptr, nullptr, nullptr);
+    if (png_ptr == nullptr)
+    {
+        reportAlways("Had trouble creating png_structp");
+        return false;
+    }
+
+    png_infop info_ptr = png_create_info_struct(png_ptr);
+    if (info_ptr == nullptr)
+    {
+        png_destroy_write_struct(&png_ptr, static_cast<png_infopp>(nullptr));
+        reportAlways("Could not create png_info");
+        return false;
+    }
+
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        reportAlways("problem writing to %s", filename.c_str());
+        return false;
+    }
+
+    FILE *const fp = fopen(filename.c_str(), "wb");
+    if (fp == nullptr)
+    {
+        reportAlways("could not open file %s for writing",
+            filename.c_str());
+        return false;
+    }
+
+    png_init_io(png_ptr, fp);
+
+    const int colortype = (surface->format->BitsPerPixel == 24) ?
+        PNG_COLOR_TYPE_RGB : PNG_COLOR_TYPE_RGB_ALPHA;
+
+    png_set_IHDR(png_ptr, info_ptr, surface->w, surface->h, 8, colortype,
+        PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
+        PNG_FILTER_TYPE_DEFAULT);
+
+    png_write_info(png_ptr, info_ptr);
+
+    png_set_packing(png_ptr);
+
+    png_bytep *const row_pointers
+        = new png_bytep[CAST_SIZE(surface->h)];
+
+    for (int i = 0; i < surface->h; i++)
+    {
+        row_pointers[i] = static_cast<png_bytep>(static_cast<uint8_t *>(
+            surface->pixels) + CAST_SIZE(i * surface->pitch));
+    }
+
+    png_write_image(png_ptr, row_pointers);
+    png_write_end(png_ptr, info_ptr);
+
+    fclose(fp);
+
+    delete [] row_pointers;
+
+    png_destroy_write_struct(&png_ptr,
+        &info_ptr);
+
+    if (SDL_MUSTLOCK(surface))
+        SDL_UnlockSurface(surface);
+
+    return true;
+}