void read_bmp(void)
{
char header[HEADER_SIZE];
FILE *input;
int x, y;
unsigned int *p;
if (!png.true_color)
G_fatal_error("PNG: cannot use BMP with indexed color");
input = fopen(png.file_name, "rb");
if (!input)
G_fatal_error("PNG: couldn't open input file %s", png.file_name);
if (fread(header, sizeof(header), 1, input) != 1)
G_fatal_error("PNG: invalid input file %s", png.file_name);
if (!read_bmp_header(header))
G_fatal_error("PNG: invalid BMP header for %s", png.file_name);
for (y = 0, p = png.grid; y < png.height; y++) {
for (x = 0; x < png.width; x++, p++) {
int b = fgetc(input);
int g = fgetc(input);
int r = fgetc(input);
int a = fgetc(input);
unsigned int c = png_get_color(r, g, b, a);
*p = c;
}
}
fclose(input);
}
void read_pgm(void)
{
char *mask_name = G_store(png.file_name);
FILE *input;
int x, y;
int i_width, i_height, maxval;
unsigned int rgb_mask = png_get_color(255, 255, 255, 0);
unsigned int *p;
if (!png.true_color)
G_fatal_error("PNG: cannot use PPM/PGM with indexed color");
mask_name[strlen(mask_name) - 2] = 'g';
input = fopen(mask_name, "rb");
if (!input)
G_fatal_error("PNG: couldn't open input mask file %s", mask_name);
if (fscanf(input, "P5 %d %d %d", &i_width, &i_height, &maxval) != 3)
G_fatal_error("PNG: invalid input mask file %s", mask_name);
fgetc(input);
if (i_width != png.width || i_height != png.height)
G_fatal_error
("PNG: input mask file has incorrect dimensions: expected: %dx%d got: %dx%d",
png.width, png.height, i_width, i_height);
G_free(mask_name);
for (y = 0, p = png.grid; y < png.height; y++) {
for (x = 0; x < png.width; x++, p++) {
unsigned int c = *p;
int k = fgetc(input);
k = k * 255 / maxval;
c &= rgb_mask;
c |= png_get_color(0, 0, 0, 255 - k);
*p = c;
}
}
fclose(input);
}
void read_ppm(void)
{
FILE *input;
int x, y;
int i_width, i_height, maxval;
unsigned int rgb_mask = png_get_color(255, 255, 255, 0);
unsigned int *p;
if (!png.true_color)
G_fatal_error("PNG: cannot use PPM/PGM with indexed color");
input = fopen(png.file_name, "rb");
if (!input)
G_fatal_error("PNG: couldn't open input file %s", png.file_name);
if (fscanf(input, "P6 %d %d %d", &i_width, &i_height, &maxval) != 3)
G_fatal_error("PNG: invalid input file %s", png.file_name);
fgetc(input);
if (i_width != png.width || i_height != png.height)
G_fatal_error
("PNG: input file has incorrect dimensions: expected: %dx%d got: %dx%d",
png.width, png.height, i_width, i_height);
for (y = 0, p = png.grid; y < png.height; y++) {
for (x = 0; x < png.width; x++, p++) {
unsigned int c = *p;
int r = fgetc(input);
int g = fgetc(input);
int b = fgetc(input);
r = r * 255 / maxval;
g = g * 255 / maxval;
b = b * 255 / maxval;
c &= ~rgb_mask;
c |= png_get_color(r, g, b, 0);
*p = c;
}
}
fclose(input);
}
/*!
\brief Draw raster row
\param n number of cells
\param row raster row (starts at 0)
\param red,grn,blu,nul red,green,blue and null value
\return next row
*/
int PNG_raster(int n, int row,
const unsigned char *red, const unsigned char *grn,
const unsigned char *blu, const unsigned char *nul)
{
int d_y0 = scale_fwd_y(row + 0);
int d_y1 = scale_fwd_y(row + 1);
int d_rows = d_y1 - d_y0;
int x0 = max(png.clip_left - dst[0][0], 0);
int x1 = min(png.clip_rite - dst[0][0], ncols);
int y0 = max(png.clip_top - d_y0, 0);
int y1 = min(png.clip_bot - d_y0, d_rows);
int x, y;
if (y1 <= y0)
return next_row(row, d_y1);
for (x = x0; x < x1; x++) {
int xx = dst[0][0] + x;
int j = trans[x];
int c;
if (masked && nul && nul[j])
continue;
c = png_get_color(red[j], grn[j], blu[j], 0);
for (y = y0; y < y1; y++) {
int yy = d_y0 + y;
png.grid[yy * png.width + xx] = c;
}
}
png.modified = 1;
return next_row(row, d_y1);
}
void read_png(void)
{
static jmp_buf jbuf;
static png_struct *png_ptr;
static png_info *info_ptr;
FILE *input;
int x, y;
unsigned int *p;
png_bytep line;
png_uint_32 i_width, i_height;
int depth, color_type;
png_ptr =
png_create_read_struct(PNG_LIBPNG_VER_STRING, &jbuf, NULL, NULL);
if (!png_ptr)
G_fatal_error("PNG: couldn't allocate PNG structure");
info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr)
G_fatal_error("PNG: couldn't allocate PNG structure");
if (setjmp(png_jmpbuf(png_ptr)))
G_fatal_error("error reading PNG file");
input = fopen(png.file_name, "rb");
if (!input)
G_fatal_error("PNG: couldn't open output file %s", png.file_name);
png_init_io(png_ptr, input);
png_read_info(png_ptr, info_ptr);
png_get_IHDR(png_ptr, info_ptr, &i_width, &i_height,
&depth, &color_type, NULL, NULL, NULL);
if (depth != 8)
G_fatal_error("PNG: input file is not 8-bit");
if (i_width != png.width || i_height != png.height)
G_fatal_error
("PNG: input file has incorrect dimensions: expected: %dx%d got: %lux%lu",
png.width, png.height, (unsigned long) i_width, (unsigned long) i_height);
if (png.true_color) {
if (color_type != PNG_COLOR_TYPE_RGB_ALPHA)
G_fatal_error("PNG: input file is not RGBA");
}
else {
if (color_type != PNG_COLOR_TYPE_PALETTE)
G_fatal_error("PNG: input file is not indexed color");
}
if (!png.true_color && png.has_alpha) {
png_bytep trans;
int num_trans;
png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, NULL);
if (num_trans != 1 || trans[0] != 0)
G_fatal_error("PNG: input file has invalid palette");
}
if (png.true_color)
png_set_invert_alpha(png_ptr);
else {
png_colorp png_pal;
int num_palette;
int i;
png_get_PLTE(png_ptr, info_ptr, &png_pal, &num_palette);
if (num_palette > 256)
num_palette = 256;
for (i = 0; i < num_palette; i++) {
png.palette[i][0] = png_pal[i].red;
png.palette[i][1] = png_pal[i].green;
png.palette[i][2] = png_pal[i].blue;
}
}
line = G_malloc(png.width * 4);
for (y = 0, p = png.grid; y < png.height; y++) {
png_bytep q = line;
png_read_row(png_ptr, q, NULL);
if (png.true_color)
for (x = 0; x < png.width; x++, p++) {
int r = *q++;
int g = *q++;
int b = *q++;
int a = *q++;
unsigned int c = png_get_color(r, g, b, a);
*p = c;
}
else
for (x = 0; x < png.width; x++, p++, q++)
*p = (png_byte) * q;
}
G_free(line);
png_read_end(png_ptr, NULL);
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
fclose(input);
}
int PNG_Graph_set(void)
{
unsigned int red, grn, blu;
int do_read = 0;
int do_map = 0;
char *p;
G_gisinit("PNG driver");
p = getenv("GRASS_PNGFILE");
if (!p || strlen(p) == 0)
p = FILE_NAME;
png.file_name = p;
p = getenv("GRASS_TRUECOLOR");
png.true_color = !p || strcmp(p, "FALSE") != 0;
G_verbose_message(_("png: truecolor status %s"),
png.true_color ? _("enabled") : _("disabled"));
p = getenv("GRASS_PNG_MAPPED");
do_map = p && strcmp(p, "TRUE") == 0;
if (do_map) {
char *ext = png.file_name + strlen(png.file_name) - 4;
if (G_strcasecmp(ext, ".bmp") != 0)
do_map = 0;
}
p = getenv("GRASS_PNG_READ");
do_read = p && strcmp(p, "TRUE") == 0;
if (do_read && access(png.file_name, 0) != 0)
do_read = 0;
png.width = screen_width;
png.height = screen_height;
png.clip_top = 0;
png.clip_bot = png.height;
png.clip_left = 0;
png.clip_rite = png.width;
p = getenv("GRASS_TRANSPARENT");
png.has_alpha = p && strcmp(p, "TRUE") == 0;
png_init_color_table();
p = getenv("GRASS_BACKGROUNDCOLOR");
if (p && *p &&
(sscanf(p, "%02x%02x%02x", &red, &grn, &blu) == 3 ||
G_str_to_color(p, (int *)&red, (int *)&grn, (int *)&blu) == 1)) {
png.background = png_get_color(red, grn, blu, png.has_alpha ? 255 : 0);
}
else {
/* 0xffffff = white, 0x000000 = black */
if (strcmp(DEFAULT_FG_COLOR, "white") == 0)
/* foreground: white, background: black */
png.background = png_get_color(0, 0, 0, png.has_alpha ? 255 : 0);
else
/* foreground: black, background: white */
png.background = png_get_color(255, 255, 255, png.has_alpha ? 255 : 0);
}
G_verbose_message(_("png: collecting to file '%s'"), png.file_name);
G_verbose_message(_("png: image size %dx%d"),
png.width, png.height);
if (do_read && do_map)
map_file();
if (!png.mapped)
png.grid = G_malloc(png.width * png.height * sizeof(unsigned int));
if (!do_read) {
PNG_Erase();
png.modified = 1;
}
if (do_read && !png.mapped)
read_image();
if (do_map && !png.mapped) {
write_image();
map_file();
}
return 0;
}
