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-rw-r--r--src/heightmap.c459
1 files changed, 459 insertions, 0 deletions
diff --git a/src/heightmap.c b/src/heightmap.c
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--- /dev/null
+++ b/src/heightmap.c
@@ -0,0 +1,459 @@
+/* $Id$ */
+
+#include "stdafx.h"
+#include "openttd.h"
+#include "variables.h"
+#include "functions.h"
+#include "heightmap.h"
+#include "clear_map.h"
+#include "table/strings.h"
+#include "void_map.h"
+#include "debug.h"
+#include "gfx.h"
+#include "gui.h"
+#include "saveload.h"
+#include "bmp.h"
+
+/**
+ * Convert RGB colors to Grayscale using 29.9% Red, 58.7% Green, 11.4% Blue
+ * (average luminosity formula) -- Dalestan
+ * This in fact is the NTSC Color Space -- TrueLight
+ */
+static inline byte RGBToGrayscale(byte red, byte green, byte blue)
+{
+ /* To avoid doubles and stuff, multiple 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 = NULL;
+
+ /* Get palette and convert it to grayscale */
+ if (info_ptr->color_type == PNG_COLOR_TYPE_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 < info_ptr->width; x++) {
+ for (y = 0; y < info_ptr->height; y++) {
+ byte *pixel = &map[y * info_ptr->width + x];
+ uint x_offset = x * info_ptr->channels;
+
+ if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) {
+ *pixel = gray_palette[row_pointers[y][x_offset]];
+ } else if (info_ptr->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 == NULL only the size of the PNG is read, otherwise a map
+ * with grayscale pixels is allocated and assigned to *map.
+ */
+static bool ReadHeightmapPNG(char *filename, uint *x, uint *y, byte **map)
+{
+ FILE *fp;
+ png_structp png_ptr = NULL;
+ png_infop info_ptr = NULL;
+
+ fp = fopen(filename, "rb");
+ if (fp == NULL) {
+ ShowErrorMessage(STR_PNGMAP_ERR_FILE_NOT_FOUND, STR_PNGMAP_ERROR, 0, 0);
+ return false;
+ }
+
+ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+ if (png_ptr == NULL) {
+ ShowErrorMessage(STR_PNGMAP_ERR_MISC, STR_PNGMAP_ERROR, 0, 0);
+ fclose(fp);
+ return false;
+ }
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (info_ptr == NULL || setjmp(png_jmpbuf(png_ptr))) {
+ ShowErrorMessage(STR_PNGMAP_ERR_MISC, STR_PNGMAP_ERROR, 0, 0);
+ fclose(fp);
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ 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, NULL);
+
+ /* Maps of wrong color-depth are not used.
+ * (this should have been taken care of by stripping alpha and 16-bit samples on load) */
+ if ((info_ptr->channels != 1) && (info_ptr->channels != 3) && (info_ptr->bit_depth != 8)) {
+ ShowErrorMessage(STR_PNGMAP_ERR_IMAGE_TYPE, STR_PNGMAP_ERROR, 0, 0);
+ fclose(fp);
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return false;
+ }
+
+ if (map != NULL) {
+ *map = malloc(info_ptr->width * info_ptr->height * sizeof(byte));
+
+ if (*map == NULL) {
+ ShowErrorMessage(STR_PNGMAP_ERR_MISC, STR_PNGMAP_ERROR, 0, 0);
+ fclose(fp);
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return false;
+ }
+
+ ReadHeightmapPNGImageData(*map, png_ptr, info_ptr);
+ }
+
+ *x = info_ptr->width;
+ *y = info_ptr->height;
+
+ fclose(fp);
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ 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 != NULL) {
+ 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 == NULL only the size of the BMP is read, otherwise a map
+ * with grayscale pixels is allocated and assigned to *map.
+ */
+static bool ReadHeightmapBMP(char *filename, uint *x, uint *y, byte **map)
+{
+ FILE *f;
+ BmpInfo info;
+ BmpData data;
+ BmpBuffer buffer;
+
+ f = fopen(filename, "rb");
+ if (f == NULL) {
+ ShowErrorMessage(STR_PNGMAP_ERR_FILE_NOT_FOUND, STR_BMPMAP_ERROR, 0, 0);
+ return false;
+ }
+
+ BmpInitializeBuffer(&buffer, f);
+
+ if (!BmpReadHeader(&buffer, &info, &data)) {
+ ShowErrorMessage(STR_BMPMAP_ERR_IMAGE_TYPE, STR_BMPMAP_ERROR, 0, 0);
+ fclose(f);
+ BmpDestroyData(&data);
+ return false;
+ }
+
+ if (map != NULL) {
+ if (!BmpReadBitmap(&buffer, &info, &data)) {
+ ShowErrorMessage(STR_BMPMAP_ERR_IMAGE_TYPE, STR_BMPMAP_ERROR, 0, 0);
+ fclose(f);
+ BmpDestroyData(&data);
+ return false;
+ }
+
+ *map = malloc(info.width * info.height * sizeof(byte));
+ if (*map == NULL) {
+ ShowErrorMessage(STR_PNGMAP_ERR_MISC, STR_BMPMAP_ERROR, 0, 0);
+ fclose(f);
+ BmpDestroyData(&data);
+ return false;
+ }
+
+ ReadHeightmapBMPImageData(*map, &info, &data);
+
+ }
+
+ BmpDestroyData(&data);
+
+ *x = info.width;
+ *y = info.height;
+
+ fclose(f);
+ return true;
+}
+
+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 (_patches.heightmap_rotation) {
+ case HM_COUNTER_CLOCKWISE:
+ width = MapSizeX();
+ height = MapSizeY();
+ break;
+ case HM_CLOCKWISE:
+ width = MapSizeY();
+ height = MapSizeX();
+ break;
+ default:
+ NOT_REACHED();
+ /* Avoids compiler warnings */
+ return;
+ }
+
+ 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 = (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 = (width - ((img_width * img_scale) / num_div)) / 2;
+ }
+
+ /* Form the landscape */
+ for (row = 0; row < height - 1; row++) {
+ for (col = 0; col < width - 1; col++) {
+ switch (_patches.heightmap_rotation) {
+ case HM_COUNTER_CLOCKWISE: tile = TileXY(col, row); break;
+ case HM_CLOCKWISE: tile = TileXY(row, col); break;
+ default: NOT_REACHED(); return;
+ }
+
+ /* Check if current tile is within the 1-pixel map edge or padding regions */
+ if ((DistanceFromEdge(tile) <= 1) ||
+ (row < row_pad) || (row >= (img_height + row_pad)) ||
+ (col < col_pad) || (col >= (img_width + col_pad))) {
+ SetTileHeight(tile, 0);
+ } else {
+ /* Use nearest neighbor resizing to scale map data.
+ * We rotate the map 45 degrees (counter)clockwise */
+ img_row = (((row - row_pad) * num_div) / img_scale);
+ switch (_patches.heightmap_rotation) {
+ 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;
+ default:
+ NOT_REACHED();
+ /* Avoids compiler warnings */
+ return;
+ }
+
+ assert(img_row < img_height);
+ assert(img_col < img_width);
+
+ /* Color scales from 0 to 255, OpenTTD height scales from 0 to 15 */
+ SetTileHeight(tile, map[img_row * img_width + img_col] / 16);
+ }
+ MakeClear(tile, CLEAR_GRASS, 3);
+ }
+ }
+}
+
+/**
+ * This function takes care of the fact that land in OpenTTD can never differ
+ * more than 1 in height
+ */
+static void FixSlopes(void)
+{
+ uint width, height;
+ uint row, col;
+ byte current_tile;
+
+ /* Adjust height difference to maximum one horizontal/vertical change. */
+ width = MapSizeX();
+ height = MapSizeY();
+
+ /* Top and left edge */
+ for (row = 1; row < height - 2; row++) {
+ for (col = 1; col < width - 2; col++) {
+ /* Find lowest tile; either the top or left one */
+ current_tile = TileHeight(TileXY(col - 1, row)); // top edge
+ 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 - 2; row > 0; row--) {
+ for (col = width - 2; col > 0; col--) {
+ /* Find lowest tile; either the bottom and right one */
+ current_tile = TileHeight(TileXY(col + 1, row)); // bottom edge
+ 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
+ */
+static bool ReadHeightMap(char *filename, uint *x, uint *y, byte **map)
+{
+ switch (_file_to_saveload.mode) {
+#ifdef WITH_PNG
+ case SL_PNG:
+ return ReadHeightmapPNG(filename, x, y, map);
+#endif /* WITH_PNG */
+ case SL_BMP:
+ return ReadHeightmapBMP(filename, x, y, map);
+
+ default:
+ NOT_REACHED();
+ /* Avoids compiler warnings */
+ return false;
+ }
+}
+
+bool GetHeightmapDimensions(char *filename, uint *x, uint *y)
+{
+ return ReadHeightMap(filename, x, y, NULL);
+}
+
+void LoadHeightmap(char *filename)
+{
+ uint x, y;
+ byte *map = NULL;
+
+ if (!ReadHeightMap(filename, &x, &y, &map)) {
+ free(map);
+ return;
+ }
+
+ GrayscaleToMapHeights(x, y, map);
+ free(map);
+
+ FixSlopes();
+ MarkWholeScreenDirty();
+}
+
+void FlatEmptyWorld(byte tile_height)
+{
+ uint width, height;
+ uint row, col;
+
+ width = MapSizeX();
+ height = MapSizeY();
+
+ for (row = 2; row < height - 2; row++) {
+ for (col = 2; col < width - 2; col++) {
+ SetTileHeight(TileXY(col, row), tile_height);
+ }
+ }
+
+ FixSlopes();
+ MarkWholeScreenDirty();
+}
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