/* * 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/>. */ /** @file heightmap.cpp Creating of maps from heightmaps. */ #include "stdafx.h" #include "heightmap.h" #include "clear_map.h" #include "void_map.h" #include "error.h" #include "saveload/saveload.h" #include "bmp.h" #include "gfx_func.h" #include "fios.h" #include "fileio_func.h" #include "table/strings.h" #include "safeguards.h" /** * Convert RGB colours to Grayscale using 29.9% Red, 58.7% Green, 11.4% Blue * (average luminosity formula, NTSC Colour Space) */ static inline byte RGBToGrayscale(byte red, byte green, byte blue) { /* To avoid doubles and stuff, multiply it with a total of 65536 (16bits), then * divide by it to normalize the value to a byte again. */ return ((red * 19595) + (green * 38470) + (blue * 7471)) / 65536; } #ifdef WITH_PNG #include <png.h> /** * The PNG Heightmap loader. */ static void ReadHeightmapPNGImageData(byte *map, png_structp png_ptr, png_infop info_ptr) { uint x, y; byte gray_palette[256]; png_bytep *row_pointers = nullptr; bool has_palette = png_get_color_type(png_ptr, info_ptr) == PNG_COLOR_TYPE_PALETTE; uint channels = png_get_channels(png_ptr, info_ptr); /* Get palette and convert it to grayscale */ if (has_palette) { int i; int palette_size; png_color *palette; bool all_gray = true; png_get_PLTE(png_ptr, info_ptr, &palette, &palette_size); for (i = 0; i < palette_size && (palette_size != 16 || all_gray); i++) { all_gray &= palette[i].red == palette[i].green && palette[i].red == palette[i].blue; gray_palette[i] = RGBToGrayscale(palette[i].red, palette[i].green, palette[i].blue); } /** * For a non-gray palette of size 16 we assume that * the order of the palette determines the height; * the first entry is the sea (level 0), the second one * level 1, etc. */ if (palette_size == 16 && !all_gray) { for (i = 0; i < palette_size; i++) { gray_palette[i] = 256 * i / palette_size; } } } row_pointers = png_get_rows(png_ptr, info_ptr); /* Read the raw image data and convert in 8-bit grayscale */ for (x = 0; x < png_get_image_width(png_ptr, info_ptr); x++) { for (y = 0; y < png_get_image_height(png_ptr, info_ptr); y++) { byte *pixel = &map[y * png_get_image_width(png_ptr, info_ptr) + x]; uint x_offset = x * channels; if (has_palette) { *pixel = gray_palette[row_pointers[y][x_offset]]; } else if (channels == 3) { *pixel = RGBToGrayscale(row_pointers[y][x_offset + 0], row_pointers[y][x_offset + 1], row_pointers[y][x_offset + 2]); } else { *pixel = row_pointers[y][x_offset]; } } } } /** * Reads the heightmap and/or size of the heightmap from a PNG file. * If map == nullptr only the size of the PNG is read, otherwise a map * with grayscale pixels is allocated and assigned to *map. */ static bool ReadHeightmapPNG(const char *filename, uint *x, uint *y, byte **map) { FILE *fp; png_structp png_ptr = nullptr; png_infop info_ptr = nullptr; fp = FioFOpenFile(filename, "rb", HEIGHTMAP_DIR); if (fp == nullptr) { ShowErrorMessage(STR_ERROR_PNGMAP, STR_ERROR_PNGMAP_FILE_NOT_FOUND, WL_ERROR); return false; } png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr); if (png_ptr == nullptr) { ShowErrorMessage(STR_ERROR_PNGMAP, STR_ERROR_PNGMAP_MISC, WL_ERROR); fclose(fp); return false; } info_ptr = png_create_info_struct(png_ptr); if (info_ptr == nullptr || setjmp(png_jmpbuf(png_ptr))) { ShowErrorMessage(STR_ERROR_PNGMAP, STR_ERROR_PNGMAP_MISC, WL_ERROR); fclose(fp); png_destroy_read_struct(&png_ptr, &info_ptr, nullptr); return false; } png_init_io(png_ptr, fp); /* Allocate memory and read image, without alpha or 16-bit samples * (result is either 8-bit indexed/grayscale or 24-bit RGB) */ png_set_packing(png_ptr); png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_PACKING | PNG_TRANSFORM_STRIP_ALPHA | PNG_TRANSFORM_STRIP_16, nullptr); /* Maps of wrong colour-depth are not used. * (this should have been taken care of by stripping alpha and 16-bit samples on load) */ if ((png_get_channels(png_ptr, info_ptr) != 1) && (png_get_channels(png_ptr, info_ptr) != 3) && (png_get_bit_depth(png_ptr, info_ptr) != 8)) { ShowErrorMessage(STR_ERROR_PNGMAP, STR_ERROR_PNGMAP_IMAGE_TYPE, WL_ERROR); fclose(fp); png_destroy_read_struct(&png_ptr, &info_ptr, nullptr); return false; } uint width = png_get_image_width(png_ptr, info_ptr); uint height = png_get_image_height(png_ptr, info_ptr); /* Check if image dimensions don't overflow a size_t to avoid memory corruption. */ if ((uint64)width * height >= (size_t)-1) { ShowErrorMessage(STR_ERROR_PNGMAP, STR_ERROR_HEIGHTMAP_TOO_LARGE, WL_ERROR); fclose(fp); png_destroy_read_struct(&png_ptr, &info_ptr, nullptr); return false; } if (map != nullptr) { *map = MallocT<byte>(width * height); ReadHeightmapPNGImageData(*map, png_ptr, info_ptr); } *x = width; *y = height; fclose(fp); png_destroy_read_struct(&png_ptr, &info_ptr, nullptr); return true; } #endif /* WITH_PNG */ /** * The BMP Heightmap loader. */ static void ReadHeightmapBMPImageData(byte *map, BmpInfo *info, BmpData *data) { uint x, y; byte gray_palette[256]; if (data->palette != nullptr) { uint i; bool all_gray = true; if (info->palette_size != 2) { for (i = 0; i < info->palette_size && (info->palette_size != 16 || all_gray); i++) { all_gray &= data->palette[i].r == data->palette[i].g && data->palette[i].r == data->palette[i].b; gray_palette[i] = RGBToGrayscale(data->palette[i].r, data->palette[i].g, data->palette[i].b); } /** * For a non-gray palette of size 16 we assume that * the order of the palette determines the height; * the first entry is the sea (level 0), the second one * level 1, etc. */ if (info->palette_size == 16 && !all_gray) { for (i = 0; i < info->palette_size; i++) { gray_palette[i] = 256 * i / info->palette_size; } } } else { /** * For a palette of size 2 we assume that the order of the palette determines the height; * the first entry is the sea (level 0), the second one is the land (level 1) */ gray_palette[0] = 0; gray_palette[1] = 16; } } /* Read the raw image data and convert in 8-bit grayscale */ for (y = 0; y < info->height; y++) { byte *pixel = &map[y * info->width]; byte *bitmap = &data->bitmap[y * info->width * (info->bpp == 24 ? 3 : 1)]; for (x = 0; x < info->width; x++) { if (info->bpp != 24) { *pixel++ = gray_palette[*bitmap++]; } else { *pixel++ = RGBToGrayscale(*bitmap, *(bitmap + 1), *(bitmap + 2)); bitmap += 3; } } } } /** * Reads the heightmap and/or size of the heightmap from a BMP file. * If map == nullptr only the size of the BMP is read, otherwise a map * with grayscale pixels is allocated and assigned to *map. */ static bool ReadHeightmapBMP(const char *filename, uint *x, uint *y, byte **map) { FILE *f; BmpInfo info; BmpData data; BmpBuffer buffer; /* Init BmpData */ memset(&data, 0, sizeof(data)); f = FioFOpenFile(filename, "rb", HEIGHTMAP_DIR); if (f == nullptr) { ShowErrorMessage(STR_ERROR_BMPMAP, STR_ERROR_PNGMAP_FILE_NOT_FOUND, WL_ERROR); return false; } BmpInitializeBuffer(&buffer, f); if (!BmpReadHeader(&buffer, &info, &data)) { ShowErrorMessage(STR_ERROR_BMPMAP, STR_ERROR_BMPMAP_IMAGE_TYPE, WL_ERROR); fclose(f); BmpDestroyData(&data); return false; } /* Check if image dimensions don't overflow a size_t to avoid memory corruption. */ if ((uint64)info.width * info.height >= (size_t)-1 / (info.bpp == 24 ? 3 : 1)) { ShowErrorMessage(STR_ERROR_BMPMAP, STR_ERROR_HEIGHTMAP_TOO_LARGE, WL_ERROR); fclose(f); BmpDestroyData(&data); return false; } if (map != nullptr) { if (!BmpReadBitmap(&buffer, &info, &data)) { ShowErrorMessage(STR_ERROR_BMPMAP, STR_ERROR_BMPMAP_IMAGE_TYPE, WL_ERROR); fclose(f); BmpDestroyData(&data); return false; } *map = MallocT<byte>(info.width * info.height); ReadHeightmapBMPImageData(*map, &info, &data); } BmpDestroyData(&data); *x = info.width; *y = info.height; fclose(f); return true; } /** * Converts a given grayscale map to something that fits in OTTD map system * and create a map of that data. * @param img_width the with of the image in pixels/tiles * @param img_height the height of the image in pixels/tiles * @param map the input map */ static void GrayscaleToMapHeights(uint img_width, uint img_height, byte *map) { /* Defines the detail of the aspect ratio (to avoid doubles) */ const uint num_div = 16384; uint width, height; uint row, col; uint row_pad = 0, col_pad = 0; uint img_scale; uint img_row, img_col; TileIndex tile; /* Get map size and calculate scale and padding values */ switch (_settings_game.game_creation.heightmap_rotation) { default: NOT_REACHED(); case HM_COUNTER_CLOCKWISE: width = MapSizeX(); height = MapSizeY(); break; case HM_CLOCKWISE: width = MapSizeY(); height = MapSizeX(); break; } if ((img_width * num_div) / img_height > ((width * num_div) / height)) { /* Image is wider than map - center vertically */ img_scale = (width * num_div) / img_width; row_pad = (1 + height - ((img_height * img_scale) / num_div)) / 2; } else { /* Image is taller than map - center horizontally */ img_scale = (height * num_div) / img_height; col_pad = (1 + width - ((img_width * img_scale) / num_div)) / 2; } if (_settings_game.construction.freeform_edges) { for (uint x = 0; x < MapSizeX(); x++) MakeVoid(TileXY(x, 0)); for (uint y = 0; y < MapSizeY(); y++) MakeVoid(TileXY(0, y)); } /* Form the landscape */ for (row = 0; row < height; row++) { for (col = 0; col < width; col++) { switch (_settings_game.game_creation.heightmap_rotation) { default: NOT_REACHED(); case HM_COUNTER_CLOCKWISE: tile = TileXY(col, row); break; case HM_CLOCKWISE: tile = TileXY(row, col); break; } /* Check if current tile is within the 1-pixel map edge or padding regions */ if ((!_settings_game.construction.freeform_edges && DistanceFromEdge(tile) <= 1) || (row < row_pad) || (row >= (height - row_pad - (_settings_game.construction.freeform_edges ? 0 : 1))) || (col < col_pad) || (col >= (width - col_pad - (_settings_game.construction.freeform_edges ? 0 : 1)))) { SetTileHeight(tile, 0); } else { /* Use nearest neighbour resizing to scale map data. * We rotate the map 45 degrees (counter)clockwise */ img_row = (((row - row_pad) * num_div) / img_scale); switch (_settings_game.game_creation.heightmap_rotation) { default: NOT_REACHED(); case HM_COUNTER_CLOCKWISE: img_col = (((width - 1 - col - col_pad) * num_div) / img_scale); break; case HM_CLOCKWISE: img_col = (((col - col_pad) * num_div) / img_scale); break; } assert(img_row < img_height); assert(img_col < img_width); uint heightmap_height = map[img_row * img_width + img_col]; if (heightmap_height > 0) { /* 0 is sea level. * Other grey scales are scaled evenly to the available height levels > 0. * (The coastline is independent from the number of height levels) */ heightmap_height = 1 + (heightmap_height - 1) * _settings_game.construction.max_heightlevel / 255; } SetTileHeight(tile, heightmap_height); } /* Only clear the tiles within the map area. */ if (IsInnerTile(tile)) { MakeClear(tile, CLEAR_GRASS, 3); } } } } /** * This function takes care of the fact that land in OpenTTD can never differ * more than 1 in height */ void FixSlopes() { uint width, height; int row, col; byte current_tile; /* Adjust height difference to maximum one horizontal/vertical change. */ width = MapSizeX(); height = MapSizeY(); /* Top and left edge */ for (row = 0; (uint)row < height; row++) { for (col = 0; (uint)col < width; col++) { current_tile = MAX_TILE_HEIGHT; if (col != 0) { /* Find lowest tile; either the top or left one */ current_tile = TileHeight(TileXY(col - 1, row)); // top edge } if (row != 0) { if (TileHeight(TileXY(col, row - 1)) < current_tile) { current_tile = TileHeight(TileXY(col, row - 1)); // left edge } } /* Does the height differ more than one? */ if (TileHeight(TileXY(col, row)) >= (uint)current_tile + 2) { /* Then change the height to be no more than one */ SetTileHeight(TileXY(col, row), current_tile + 1); } } } /* Bottom and right edge */ for (row = height - 1; row >= 0; row--) { for (col = width - 1; col >= 0; col--) { current_tile = MAX_TILE_HEIGHT; if ((uint)col != width - 1) { /* Find lowest tile; either the bottom and right one */ current_tile = TileHeight(TileXY(col + 1, row)); // bottom edge } if ((uint)row != height - 1) { if (TileHeight(TileXY(col, row + 1)) < current_tile) { current_tile = TileHeight(TileXY(col, row + 1)); // right edge } } /* Does the height differ more than one? */ if (TileHeight(TileXY(col, row)) >= (uint)current_tile + 2) { /* Then change the height to be no more than one */ SetTileHeight(TileXY(col, row), current_tile + 1); } } } } /** * Reads the heightmap with the correct file reader. * @param dft Type of image file. * @param filename Name of the file to load. * @param[out] x Length of the image. * @param[out] y Height of the image. * @param[in,out] map If not \c nullptr, destination to store the loaded block of image data. * @return Whether loading was successful. */ static bool ReadHeightMap(DetailedFileType dft, const char *filename, uint *x, uint *y, byte **map) { switch (dft) { default: NOT_REACHED(); #ifdef WITH_PNG case DFT_HEIGHTMAP_PNG: return ReadHeightmapPNG(filename, x, y, map); #endif /* WITH_PNG */ case DFT_HEIGHTMAP_BMP: return ReadHeightmapBMP(filename, x, y, map); } } /** * Get the dimensions of a heightmap. * @param dft Type of image file. * @param filename to query * @param x dimension x * @param y dimension y * @return Returns false if loading of the image failed. */ bool GetHeightmapDimensions(DetailedFileType dft, const char *filename, uint *x, uint *y) { return ReadHeightMap(dft, filename, x, y, nullptr); } /** * Load a heightmap from file and change the map in his current dimensions * to a landscape representing the heightmap. * It converts pixels to height. The brighter, the higher. * @param dft Type of image file. * @param filename of the heightmap file to be imported */ void LoadHeightmap(DetailedFileType dft, const char *filename) { uint x, y; byte *map = nullptr; if (!ReadHeightMap(dft, filename, &x, &y, &map)) { free(map); return; } GrayscaleToMapHeights(x, y, map); free(map); FixSlopes(); MarkWholeScreenDirty(); } /** * Make an empty world where all tiles are of height 'tile_height'. * @param tile_height of the desired new empty world */ void FlatEmptyWorld(byte tile_height) { int edge_distance = _settings_game.construction.freeform_edges ? 0 : 2; for (uint row = edge_distance; row < MapSizeY() - edge_distance; row++) { for (uint col = edge_distance; col < MapSizeX() - edge_distance; col++) { SetTileHeight(TileXY(col, row), tile_height); } } FixSlopes(); MarkWholeScreenDirty(); }