1 /* $Id$ */

     2 

     3 /** @file grf.cpp */

     4 

     5 #include "../stdafx.h"

     6 #include "../gfx.h"

     7 #include "../fileio.h"

     8 #include "../variables.h"

     9 #include "../debug.h"

    10 #include "png.hpp"

    11 #include <png.h>

    12 

    13 #define PNG_SLOT 62

    14 

    15 static void PNGAPI png_my_read(png_structp png_ptr, png_bytep data, png_size_t length)

    16 {

    17 	FioReadBlock(data, length);

    18 }

    19 

    20 static void PNGAPI png_my_error(png_structp png_ptr, png_const_charp message)

    21 {

    22 	DEBUG(sprite, 0, "ERROR (libpng): %s - %s", message, (char *)png_get_error_ptr(png_ptr));

    23 	longjmp(png_ptr->jmpbuf, 1);

    24 }

    25 

    26 static void PNGAPI png_my_warning(png_structp png_ptr, png_const_charp message)

    27 {

    28 	DEBUG(sprite, 0, "WARNING (libpng): %s - %s", message, (char *)png_get_error_ptr(png_ptr));

    29 }

    30 

    31 static bool OpenPNGFile(const char *filename, uint32 id, bool mask)

    32 {

    33 	char png_file[MAX_PATH];

    34 

    35 	snprintf(png_file, sizeof(png_file), "sprites" PATHSEP "%s" PATHSEP "%d%s.png", filename, id, mask ? "m" : "");

    36 	if (FioCheckFileExists(png_file)) {

    37 		FioOpenFile(PNG_SLOT, png_file);

    38 		return true;

    39 	}

    40 

    41 	/* TODO -- Add TAR support */

    42 	return false;

    43 }

    44 

    45 static bool LoadPNG(SpriteLoader::Sprite *sprite, const char *filename, uint32 id, bool mask)

    46 {

    47 	png_byte header[8];

    48 	png_structp png_ptr;

    49 	png_infop info_ptr, end_info;

    50 	uint bit_depth, color_type;

    51 	uint i, pixelsize;

    52 	png_bytep row_pointer;

    53 	SpriteLoader::CommonPixel *dst;

    54 

    55 	if (!OpenPNGFile(filename, id, mask)) return mask; // If mask is true, and file not found, continue true anyway, as it isn't a show-stopper

    56 

    57 	/* Check the header */

    58 	FioReadBlock(header, 8);

    59 	if (png_sig_cmp(header, 0, 8) != 0) return false;

    60 

    61 	/* Create the reader */

    62 	png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, (png_voidp)NULL, png_my_error, png_my_warning);

    63 	if (png_ptr == NULL) return false;

    64 

    65 	/* Create initial stuff */

    66 	info_ptr = png_create_info_struct(png_ptr);

    67 	if (info_ptr == NULL) {

    68 		png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL);

    69 		return false;

    70 	}

    71 	end_info = png_create_info_struct(png_ptr);

    72 	if (end_info == NULL) {

    73 		png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL);

    74 		return false;

    75 	}

    76 

    77 	/* Make sure that upon error, we can clean up graceful */

    78 	if (setjmp(png_jmpbuf(png_ptr))) {

    79 		png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);

    80 		return false;

    81 	}

    82 

    83 	/* Read the file */

    84 	png_set_read_fn(png_ptr, NULL, png_my_read);

    85 	png_set_sig_bytes(png_ptr, 8);

    86 

    87 	png_read_info(png_ptr, info_ptr);

    88 

    89 	if (!mask) {

    90 		/* Read the text chunks */

    91 		png_textp text_ptr;

    92 		int num_text = 0;

    93 		png_get_text(png_ptr, info_ptr, &text_ptr, &num_text);

    94 		if (num_text == 0) DEBUG(misc, 0, "Warning: PNG Sprite '%s/%d.png' doesn't have x_offs and y_offs; expect graphical problems", filename, id);

    95 		for (int i = 0; i < num_text; i++) {

    96 			/* x_offs and y_offs are in the text-chunk of PNG */

    97 			if (strcmp("x_offs", text_ptr[i].key) == 0) sprite->x_offs = strtol(text_ptr[i].text, NULL, 0);

    98 			if (strcmp("y_offs", text_ptr[i].key) == 0) sprite->y_offs = strtol(text_ptr[i].text, NULL, 0);

    99 		}

   100 

   101 		sprite->height = info_ptr->height;

   102 		sprite->width  = info_ptr->width;

   103 		sprite->data = CallocT<SpriteLoader::CommonPixel>(sprite->width * sprite->height);

   104 	}

   105 

   106 	bit_depth  = png_get_bit_depth(png_ptr, info_ptr);

   107 	color_type = png_get_color_type(png_ptr, info_ptr);

   108 

   109 	if (mask && (bit_depth != 8 || color_type != PNG_COLOR_TYPE_PALETTE)) {

   110 		DEBUG(misc, 0, "Ignoring mask for SpriteID %d as it isn't a 8 bit palette image", id);

   111 		return true;

   112 	}

   113 

   114 	if (!mask) {

   115 		if (bit_depth == 16) png_set_strip_16(png_ptr);

   116 

   117 		if (color_type == PNG_COLOR_TYPE_PALETTE) {

   118 			png_set_palette_to_rgb(png_ptr);

   119 			color_type = PNG_COLOR_TYPE_RGB;

   120 		}

   121 		if (color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {

   122 			png_set_gray_to_rgb(png_ptr);

   123 			color_type = PNG_COLOR_TYPE_RGB;

   124 		}

   125 

   126 #ifdef TTD_LITTLE_ENDIAN

   127 		png_set_bgr(png_ptr);

   128 #else

   129 		if (color_type == PNG_COLOR_TYPE_RGB_ALPHA) png_set_swap_alpha(png_ptr);

   130 #endif

   131 

   132 		if (color_type == PNG_COLOR_TYPE_RGB) {

   133 #ifdef TTD_LITTLE_ENDIAN

   134 			png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);

   135 #else

   136 			png_set_filler(png_ptr, 0xff, PNG_FILLER_BEFORE);

   137 #endif

   138 		}

   139 

   140 		pixelsize = sizeof(uint32);

   141 	} else {

   142 		pixelsize = sizeof(uint8);

   143 	}

   144 

   145 	row_pointer = (png_byte *)malloc(info_ptr->width * pixelsize);

   146 	if (row_pointer == NULL) {

   147 		png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);

   148 		return false;

   149 	}

   150 

   151 	for (i = 0; i < info_ptr->height; i++) {

   152 		png_read_row(png_ptr, row_pointer, NULL);

   153 

   154 		dst = sprite->data + i * info_ptr->width;

   155 

   156 		for (uint x = 0; x < info_ptr->width; x++) {

   157 			if (mask) {

   158 				if (row_pointer[x * sizeof(uint8)] != 0) {

   159 					dst[x].b = 0;

   160 					dst[x].g = 0;

   161 					dst[x].r = 0;

   162 					/* Alpha channel is used from the original image (to allow transparency in remap colors) */

   163 					dst[x].m = row_pointer[x * sizeof(uint8)];

   164 				}

   165 			} else {

   166 				dst[x].b = row_pointer[x * sizeof(uint32) + 0];

   167 				dst[x].g = row_pointer[x * sizeof(uint32) + 1];

   168 				dst[x].r = row_pointer[x * sizeof(uint32) + 2];

   169 				dst[x].a = row_pointer[x * sizeof(uint32) + 3];

   170 				dst[x].m = 0;

   171 			}

   172 		}

   173 	}

   174 

   175 	free(row_pointer);

   176 	png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);

   177 

   178 	return true;

   179 }

   180 

   181 bool SpriteLoaderPNG::LoadSprite(SpriteLoader::Sprite *sprite, const char *filename, uint32 file_pos)

   182 {

   183 	if (!LoadPNG(sprite, filename, file_pos, false)) return false;

   184 	if (!LoadPNG(sprite, filename, file_pos, true)) return false;

   185 	return true;

   186 }