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

}