xenocara/dist/Mesa/progs/samples/loadppm.c
2006-11-25 18:56:37 +00:00

73 lines
1.3 KiB
C

typedef struct {
size_t sizeX, sizeY;
GLubyte *data;
} PPMImage;
static PPMImage *LoadPPM(const char *filename)
{
char buff[16];
PPMImage *result;
FILE *fp;
int maxval;
fp = fopen(filename, "rb");
if (!fp)
{
fprintf(stderr, "Unable to open file `%s'\n", filename);
exit(1);
}
if (!fgets(buff, sizeof(buff), fp))
{
perror(filename);
exit(1);
}
if (buff[0] != 'P' || buff[1] != '6')
{
fprintf(stderr, "Invalid image format (must be `P6')\n");
exit(1);
}
result = (PPMImage *) malloc(sizeof(PPMImage));
if (!result)
{
fprintf(stderr, "Unable to allocate memory\n");
exit(1);
}
if (fscanf(fp, "%lu %lu", &result->sizeX, &result->sizeY) != 2)
{
fprintf(stderr, "Error loading image `%s'\n", filename);
exit(1);
}
if (fscanf(fp, "%d", &maxval) != 1)
{
fprintf(stderr, "Error loading image `%s'\n", filename);
exit(1);
}
while (fgetc(fp) != '\n')
;
result->data = (GLubyte *) malloc(3 * result->sizeX * result->sizeY);
if (!result)
{
fprintf(stderr, "Unable to allocate memory\n");
exit(1);
}
if (fread(result->data, 3 * result->sizeX, result->sizeY, fp) != result->sizeY)
{
fprintf(stderr, "Error loading image `%s'\n", filename);
exit(1);
}
fclose(fp);
return result;
}