splash.cpp

Go to the documentation of this file.

/*
 * This file is part of OpenTTD.
 * OpenTTD 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, version 2.
 * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */
 
#include "../../stdafx.h"
#include "../../openttd.h"
#include "../../debug.h"
#include "../../gfx_func.h"
#include "../../fileio_func.h"
#include "../../blitter/factory.hpp"
#include "../../core/mem_func.hpp"
 
#include "splash.h"
 
#ifdef WITH_PNG
 
#include <png.h>
 
#include "../../safeguards.h"
 
static void PNGAPI png_my_error(png_structp png_ptr, png_const_charp message)
{
  DEBUG(misc, 0, "[libpng] error: %s - %s", message, (char *)png_get_error_ptr(png_ptr));
  longjmp(png_jmpbuf(png_ptr), 1);
}
 
static void PNGAPI png_my_warning(png_structp png_ptr, png_const_charp message)
{
  DEBUG(misc, 1, "[libpng] warning: %s - %s", message, (char *)png_get_error_ptr(png_ptr));
}
 
void DisplaySplashImage()
{
  FILE *f = FioFOpenFile(SPLASH_IMAGE_FILE, "r", BASESET_DIR);
  if (f == nullptr) return;
 
  png_byte header[8];
  fread(header, sizeof(png_byte), 8, f);
  if (png_sig_cmp(header, 0, 8) != 0) {
    fclose(f);
    return;
  }
 
  png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, (png_voidp) nullptr, png_my_error, png_my_warning);
 
  if (png_ptr == nullptr) {
    fclose(f);
    return;
  }
 
  png_infop info_ptr = png_create_info_struct(png_ptr);
  if (info_ptr == nullptr) {
    png_destroy_read_struct(&png_ptr, (png_infopp)nullptr, (png_infopp)nullptr);
    fclose(f);
    return;
  }
 
  png_infop end_info = png_create_info_struct(png_ptr);
  if (end_info == nullptr) {
    png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)nullptr);
    fclose(f);
    return;
  }
 
  if (setjmp(png_jmpbuf(png_ptr))) {
    png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
    fclose(f);
    return;
  }
 
  png_init_io(png_ptr, f);
  png_set_sig_bytes(png_ptr, 8);
 
  png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, nullptr);
 
  uint width      = png_get_image_width(png_ptr, info_ptr);
  uint height     = png_get_image_height(png_ptr, info_ptr);
  uint bit_depth  = png_get_bit_depth(png_ptr, info_ptr);
  uint color_type = png_get_color_type(png_ptr, info_ptr);
 
  if (color_type != PNG_COLOR_TYPE_PALETTE || bit_depth != 8) {
    png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
    fclose(f);
    return;
  }
 
  if (!png_get_valid(png_ptr, info_ptr, PNG_INFO_PLTE)) {
    png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
    fclose(f);
    return;
  }
 
  png_colorp palette;
  int num_palette;
  png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette);
 
  png_bytep *row_pointers = png_get_rows(png_ptr, info_ptr);
 
  if (width > (uint) _screen.width) width = _screen.width;
  if (height > (uint) _screen.height) height = _screen.height;
 
  uint xoff = (_screen.width - width) / 2;
  uint yoff = (_screen.height - height) / 2;
 
  switch (BlitterFactory::GetCurrentBlitter()->GetScreenDepth()) {
    case 8: {
        uint8 *dst_ptr = (uint8 *)_screen.dst_ptr;
        /* Initialize buffer */
        MemSetT(dst_ptr, 0xff, _screen.pitch * _screen.height);
 
        for (uint y = 0; y < height; y++) {
          uint8 *src = row_pointers[y];
          uint8 *dst = dst_ptr + (yoff + y) * _screen.pitch + xoff;
 
          memcpy(dst, src, width);
        }
 
        for (int i = 0; i < num_palette; i++) {
          _cur_palette.palette[i].a = i == 0 ? 0 : 0xff;
          _cur_palette.palette[i].r = palette[i].red;
          _cur_palette.palette[i].g = palette[i].green;
          _cur_palette.palette[i].b = palette[i].blue;
        }
 
        _cur_palette.palette[0xff].a = 0xff;
        _cur_palette.palette[0xff].r = 0;
        _cur_palette.palette[0xff].g = 0;
        _cur_palette.palette[0xff].b = 0;
 
        _cur_palette.first_dirty = 0;
        _cur_palette.count_dirty = 256;
        break;
      }
    case 32: {
        uint32 *dst_ptr = (uint32 *)_screen.dst_ptr;
        /* Initialize buffer */
        MemSetT(dst_ptr, 0, _screen.pitch * _screen.height);
 
        for (uint y = 0; y < height; y++) {
          uint8 *src = row_pointers[y];
          uint32 *dst = dst_ptr + (yoff + y) * _screen.pitch + xoff;
 
          for (uint x = 0; x < width; x++) {
            dst[x] = palette[src[x]].blue | (palette[src[x]].green << 8) | (palette[src[x]].red << 16) | 0xff000000;
          }
        }
        break;
      }
  }
 
  png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
  fclose(f);
  return;
}
 
 
 
#else /* WITH_PNG */
 
void DisplaySplashImage() {}
 
#endif /* WITH_PNG */