OpenTTD-patches/heightmap.c
2006-09-04 20:40:33 +00:00

460 lines
12 KiB
C

/* $Id$ */
#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 >= (height - row_pad)) ||
(col < col_pad) || (col >= (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();
}