--- /dev/null
+
+/* pcx.c */
+
+#include "image.h"
+
+#define PCX_MAGIC 0x0a /* first byte in a PCX image file */
+#define PCX_LAST_VERSION 5 /* last acceptable version number */
+#define PCX_ENCODING 1 /* PCX encoding method */
+#define PCX_256COLORS_MAGIC 0x0c /* first byte of a PCX 256 color map */
+#define PCX_MAXDEPTH 8 /* supports up to 8 bits per pixel */
+#define PCX_MAXCOLORS 256 /* maximum number of colors */
+#define PCX_HEADER_SIZE 128
+#define PCX_PALETTE_SIZE (3 * PCX_MAXCOLORS)
+
+struct PCX_Header
+{
+ unsigned char signature; /* PCX file identifier */
+ unsigned char version; /* version compatibility level */
+ unsigned char encoding; /* encoding method */
+ unsigned char bits_per_pixel; /* bits per pixel, or depth */
+ unsigned short xmin; /* X position of left edge */
+ unsigned short ymin; /* Y position of top edge */
+ unsigned short xmax; /* X position of right edge */
+ unsigned short ymax; /* Y position of bottom edge */
+ unsigned short hres; /* X screen resolution of source image */
+ unsigned short vres; /* Y screen resolution of source image */
+ unsigned char palette[16][3]; /* PCX color map */
+ unsigned char reserved; /* should be 0, 1 if std res fax */
+ unsigned char color_planes; /* bit planes in image */
+ unsigned short bytes_per_line;/* byte delta between scanlines */
+ unsigned short palette_type; /* 0 = undef, 1 = color, 2 = grayscale */
+ unsigned char filler[58]; /* fill to struct size of 128 */
+};
+
+static boolean PCX_LoadImage(); /* Routine to load PCX bitmap */
+static boolean PCX_LoadColormap(); /* Routine to load PCX colormap */
+
+Image *Read_PCX_to_Image(char *filename)
+{
+ FILE *file;
+ unsigned char buffer[PCX_HEADER_SIZE];
+ struct PCX_Header pcx;
+ Image *image;
+ int width, height, depth;
+
+ if (!(file = fopen(filename, "r")))
+ return NULL;
+
+ /* read PCX header */
+ if (fread(buffer, 1, PCX_HEADER_SIZE, file) != PCX_HEADER_SIZE)
+ {
+ fclose(file);
+ return NULL;
+ }
+
+ pcx.signature = buffer[0];
+ pcx.version = buffer[1];
+ pcx.encoding = buffer[2];
+ pcx.bits_per_pixel = buffer[3];
+ pcx.xmin = buffer[4] + 256 * buffer[5];
+ pcx.ymin = buffer[6] + 256 * buffer[7];
+ pcx.xmax = buffer[8] + 256 * buffer[9];
+ pcx.ymax = buffer[10] + 256 * buffer[11];
+ pcx.color_planes = buffer[65];
+ pcx.bytes_per_line = buffer[66] + 256 * buffer[67];
+ pcx.palette_type = buffer[68] + 256 * buffer[69];
+
+ width = pcx.xmax - pcx.xmin + 1;
+ height = pcx.ymax - pcx.ymin + 1;
+ depth = pcx.bits_per_pixel;
+
+ if (pcx.signature != PCX_MAGIC || pcx.version > PCX_LAST_VERSION ||
+ pcx.encoding != PCX_ENCODING || pcx.color_planes > PCX_MAXDEPTH ||
+ width < 0 || height < 0)
+ {
+ fclose(file);
+ return NULL;
+ }
+
+ if (options.verbose)
+ {
+ printf("%s is a %dx%d PC Paintbrush image with %d bitplanes\n",
+ filename, pcx.xmax, pcx.ymax,
+ pcx.color_planes);
+ printf("depth: %d\n", pcx.bits_per_pixel);
+ printf("bytes_per_line: %d\n", pcx.bytes_per_line);
+ printf("palette type: %s\n",
+ (pcx.palette_type == 1 ? "color" :
+ pcx.palette_type == 2 ? "grayscale" : "undefined"));
+ }
+
+ /* allocate new image structure */
+ image = newRGBImage(width, height, depth);
+
+ /* read compressed bitmap data */
+ if (!PCX_LoadImage(file, image))
+ {
+ fclose(file);
+ return image;
+ }
+
+ /* read colormap data */
+ if (!PCX_LoadColormap(file, image))
+ {
+ fclose(file);
+ return image;
+ }
+
+ fclose(file);
+ return(image);
+}
+
+static boolean PCX_LoadImage(FILE *file, Image *image)
+{
+ /* Run Length Encoding: If the two high bits are set,
+ * then the low 6 bits contain a repeat count, and the byte to
+ * repeat is the next byte in the file. If the two high bits are
+ * not set, then this is the byte to write.
+ */
+
+ register unsigned char *ptr, *ptr_last;
+ int value, count;
+
+ ptr = image->data;
+ ptr_last = ptr + (image->width * image->height * image->pixlen);
+
+ while (ptr < ptr_last)
+ {
+ if ((value = fgetc(file)) == EOF)
+ return FALSE;
+
+ if ((value & 0xc0) == 0xc0)
+ {
+ count = value & 0x3f;
+
+ if ((value = fgetc(file)) == EOF)
+ return FALSE;
+
+ for ( ; count && (ptr < ptr_last); count--)
+ *ptr++ = (unsigned char)value;
+
+ if (count)
+ printf("Repeat count spans end of image!\n");
+ }
+ else
+ *ptr++ = (unsigned char)value;
+ }
+
+ return TRUE;
+}
+
+static boolean PCX_LoadColormap(FILE *file, Image *image)
+{
+ unsigned char buffer[PCX_PALETTE_SIZE];
+ int i, result, magic;
+
+ /* read colormap magic byte */
+ if ((magic = fgetc(file)) == EOF)
+ return FALSE;
+
+ if (magic != PCX_256COLORS_MAGIC)
+ return FALSE;
+
+ /* read PCX 256 colors colormap */
+ if ((result = fread(buffer, 1, PCX_PALETTE_SIZE, file)) != PCX_PALETTE_SIZE)
+ return FALSE;
+
+ for (i=0; i<PCX_MAXCOLORS; i++)
+ {
+ image->rgb.red[i] = buffer[i*3 + 0] << 8;
+ image->rgb.green[i] = buffer[i*3 + 1] << 8;
+ image->rgb.blue[i] = buffer[i*3 + 2] << 8;
+ }
+ image->rgb.used = PCX_MAXCOLORS;
+
+ return TRUE;
+}
projects / rocksndiamonds.git / commitdiff