tr_image.c

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	byte	*out, *pix;
	int		xmax, ymax;

	*pic = NULL;
	*palette = NULL;

	//
	// load the file
	//
	len = ri.FS_ReadFile( ( char * ) filename, (void **)&raw);
	if (!raw) {
		return;
	}

	//
	// parse the PCX file
	//
	pcx = (pcx_t *)raw;
	raw = &pcx->data;

  	xmax = LittleShort(pcx->xmax);
    ymax = LittleShort(pcx->ymax);

	if (pcx->manufacturer != 0x0a
		|| pcx->version != 5
		|| pcx->encoding != 1
		|| pcx->bits_per_pixel != 8
		|| xmax >= 1024
		|| ymax >= 1024)
	{
		ri.Printf (PRINT_ALL, "Bad pcx file %s (%i x %i) (%i x %i)\n", filename, xmax+1, ymax+1, pcx->xmax, pcx->ymax);
		return;
	}

	out = ri.Malloc ( (ymax+1) * (xmax+1) );

	*pic = out;

	pix = out;

	if (palette)
	{
		*palette = ri.Malloc(768);
		Com_Memcpy (*palette, (byte *)pcx + len - 768, 768);
	}

	if (width)
		*width = xmax+1;
	if (height)
		*height = ymax+1;
// FIXME: use bytes_per_line here?

	for (y=0 ; y<=ymax ; y++, pix += xmax+1)
	{
		for (x=0 ; x<=xmax ; )
		{
			dataByte = *raw++;

			if((dataByte & 0xC0) == 0xC0)
			{
				runLength = dataByte & 0x3F;
				dataByte = *raw++;
			}
			else
				runLength = 1;

			while(runLength-- > 0)
				pix[x++] = dataByte;
		}

	}

	if ( raw - (byte *)pcx > len)
	{
		ri.Printf (PRINT_DEVELOPER, "PCX file %s was malformed", filename);
		ri.Free (*pic);
		*pic = NULL;
	}

	ri.FS_FreeFile (pcx);
}


/*
==============
LoadPCX32
==============
*/
static void LoadPCX32 ( const char *filename, byte **pic, int *width, int *height) {
	byte	*palette;
	byte	*pic8;
	int		i, c, p;
	byte	*pic32;

	LoadPCX (filename, &pic8, &palette, width, height);
	if (!pic8) {
		*pic = NULL;
		return;
	}

	c = (*width) * (*height);
	pic32 = *pic = ri.Malloc(4 * c );
	for (i = 0 ; i < c ; i++) {
		p = pic8[i];
		pic32[0] = palette[p*3];
		pic32[1] = palette[p*3 + 1];
		pic32[2] = palette[p*3 + 2];
		pic32[3] = 255;
		pic32 += 4;
	}

	ri.Free (pic8);
	ri.Free (palette);
}

/*
=========================================================

TARGA LOADING

=========================================================
*/

/*
=============
LoadTGA
=============
*/
static void LoadTGA ( const char *name, byte **pic, int *width, int *height)
{
	int		columns, rows, numPixels;
	byte	*pixbuf;
	int		row, column;
	byte	*buf_p;
	byte	*buffer;
	TargaHeader	targa_header;
	byte		*targa_rgba;

	*pic = NULL;

	//
	// load the file
	//
	ri.FS_ReadFile ( ( char * ) name, (void **)&buffer);
	if (!buffer) {
		return;
	}

	buf_p = buffer;

	targa_header.id_length = *buf_p++;
	targa_header.colormap_type = *buf_p++;
	targa_header.image_type = *buf_p++;
	
	targa_header.colormap_index = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.colormap_length = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.colormap_size = *buf_p++;
	targa_header.x_origin = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.y_origin = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.width = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.height = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.pixel_size = *buf_p++;
	targa_header.attributes = *buf_p++;

	if (targa_header.image_type!=2 
		&& targa_header.image_type!=10
		&& targa_header.image_type != 3 ) 
	{
		ri.Error (ERR_DROP, "LoadTGA: Only type 2 (RGB), 3 (gray), and 10 (RGB) TGA images supported\n");
	}

	if ( targa_header.colormap_type != 0 )
	{
		ri.Error( ERR_DROP, "LoadTGA: colormaps not supported\n" );
	}

	if ( ( targa_header.pixel_size != 32 && targa_header.pixel_size != 24 ) && targa_header.image_type != 3 )
	{
		ri.Error (ERR_DROP, "LoadTGA: Only 32 or 24 bit images supported (no colormaps)\n");
	}

	columns = targa_header.width;
	rows = targa_header.height;
	numPixels = columns * rows;

	if (width)
		*width = columns;
	if (height)
		*height = rows;

	targa_rgba = ri.Malloc (numPixels*4);
	*pic = targa_rgba;

	if (targa_header.id_length != 0)
		buf_p += targa_header.id_length;  // skip TARGA image comment
	
	if ( targa_header.image_type==2 || targa_header.image_type == 3 )
	{ 
		// Uncompressed RGB or gray scale image
		for(row=rows-1; row>=0; row--) 
		{
			pixbuf = targa_rgba + row*columns*4;
			for(column=0; column<columns; column++) 
			{
				unsigned char red,green,blue,alphabyte;
				switch (targa_header.pixel_size) 
				{
					
				case 8:
					blue = *buf_p++;
					green = blue;
					red = blue;
					*pixbuf++ = red;
					*pixbuf++ = green;
					*pixbuf++ = blue;
					*pixbuf++ = 255;
					break;

				case 24:
					blue = *buf_p++;
					green = *buf_p++;
					red = *buf_p++;
					*pixbuf++ = red;
					*pixbuf++ = green;
					*pixbuf++ = blue;
					*pixbuf++ = 255;
					break;
				case 32:
					blue = *buf_p++;
					green = *buf_p++;
					red = *buf_p++;
					alphabyte = *buf_p++;
					*pixbuf++ = red;
					*pixbuf++ = green;
					*pixbuf++ = blue;
					*pixbuf++ = alphabyte;
					break;
				default:
					ri.Error( ERR_DROP, "LoadTGA: illegal pixel_size '%d' in file '%s'\n", targa_header.pixel_size, name );
					break;
				}
			}
		}
	}
	else if (targa_header.image_type==10) {   // Runlength encoded RGB images
		unsigned char red,green,blue,alphabyte,packetHeader,packetSize,j;

		red = 0;
		green = 0;
		blue = 0;
		alphabyte = 0xff;

		for(row=rows-1; row>=0; row--) {
			pixbuf = targa_rgba + row*columns*4;
			for(column=0; column<columns; ) {
				packetHeader= *buf_p++;
				packetSize = 1 + (packetHeader & 0x7f);
				if (packetHeader & 0x80) {        // run-length packet
					switch (targa_header.pixel_size) {
						case 24:
								blue = *buf_p++;
								green = *buf_p++;
								red = *buf_p++;
								alphabyte = 255;
								break;
						case 32:
								blue = *buf_p++;
								green = *buf_p++;
								red = *buf_p++;
								alphabyte = *buf_p++;
								break;
						default:
							ri.Error( ERR_DROP, "LoadTGA: illegal pixel_size '%d' in file '%s'\n", targa_header.pixel_size, name );
							break;
					}
	
					for(j=0;j<packetSize;j++) {
						*pixbuf++=red;
						*pixbuf++=green;
						*pixbuf++=blue;
						*pixbuf++=alphabyte;
						column++;
						if (column==columns) { // run spans across rows
							column=0;
							if (row>0)
								row--;
							else
								goto breakOut;
							pixbuf = targa_rgba + row*columns*4;
						}
					}
				}
				else {                            // non run-length packet
					for(j=0;j<packetSize;j++) {
						switch (targa_header.pixel_size) {
							case 24:
									blue = *buf_p++;
									green = *buf_p++;
									red = *buf_p++;
									*pixbuf++ = red;
									*pixbuf++ = green;
									*pixbuf++ = blue;
									*pixbuf++ = 255;
									break;
							case 32:
									blue = *buf_p++;
									green = *buf_p++;
									red = *buf_p++;
									alphabyte = *buf_p++;
									*pixbuf++ = red;
									*pixbuf++ = green;
									*pixbuf++ = blue;
									*pixbuf++ = alphabyte;
									break;
							default:
								ri.Error( ERR_DROP, "LoadTGA: illegal pixel_size '%d' in file '%s'\n", targa_header.pixel_size, name );
								break;
						}
						column++;
						if (column==columns) { // pixel packet run spans across rows
							column=0;
							if (row>0)
								row--;
							else
								goto breakOut;
							pixbuf = targa_rgba + row*columns*4;
						}						
					}
				}
			}
			breakOut:;
		}
	}

#if 0 
  // TTimo: this is the chunk of code to ensure a behavior that meets TGA specs 
  // bk0101024 - fix from Leonardo
  // bit 5 set => top-down
  if (targa_header.attributes & 0x20) {
    unsigned char *flip = (unsigned char*)malloc (columns*4);
    unsigned char *src, *dst;

    for (row = 0; row < rows/2; row++) {
      src = targa_rgba + row * 4 * columns;
      dst = targa_rgba + (rows - row - 1) * 4 * columns;

      memcpy (flip, src, columns*4);
      memcpy (src, dst, columns*4);
      memcpy (dst, flip, columns*4);
    }
    free (flip);
  }
#endif
  // instead we just print a warning
  if (targa_header.attributes & 0x20) {
    ri.Printf( PRINT_WARNING, "WARNING: '%s' TGA file header declares top-down image, ignoring\n", name);
  }

  ri.FS_FreeFile (buffer);
}

static void LoadJPG( const char *filename, unsigned char **pic, int *width, int *height ) {
  /* This struct contains the JPEG decompression parameters and pointers to
   * working space (which is allocated as needed by the JPEG library).
   */
  struct jpeg_decompress_struct cinfo;
  /* We use our private extension JPEG error handler.
   * Note that this struct must live as long as the main JPEG parameter
   * struct, to avoid dangling-pointer problems.
   */
  /* This struct represents a JPEG error handler.  It is declared separately
   * because applications often want to supply a specialized error handler
   * (see the second half of this file for an example).  But here we just
   * take the easy way out and use the standard error handler, which will
   * print a message on stderr and call exit() if compression fails.
   * Note that this struct must live as long as the main JPEG parameter
   * struct, to avoid dangling-pointer problems.
   */
  struct jpeg_error_mgr jerr;
  /* More stuff */
  JSAMPARRAY buffer;		/* Output row buffer */
  int row_stride;		/* physical row width in output buffer */
  unsigned char *out;
  byte	*fbuffer;
  byte  *bbuf;

  /* In this example we want to open the input file before doing anything else,
   * so that the setjmp() error recovery below can assume the file is open.
   * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
   * requires it in order to read binary files.
   */

  ri.FS_ReadFile ( ( char * ) filename, (void **)&fbuffer);
  if (!fbuffer) {
	return;
  }

  /* Step 1: allocate and initialize JPEG decompression object */

  /* We have to set up the error handler first, in case the initialization
   * step fails.  (Unlikely, but it could happen if you are out of memory.)
   * This routine fills in the contents of struct jerr, and returns jerr's
   * address which we place into the link field in cinfo.
   */
  cinfo.err = jpeg_std_error(&jerr);

  /* Now we can initialize the JPEG decompression object. */
  jpeg_create_decompress(&cinfo);

  /* Step 2: specify data source (eg, a file) */

  jpeg_stdio_src(&cinfo, fbuffer);

  /* Step 3: read file parameters with jpeg_read_header() */

  (void) jpeg_read_header(&cinfo, TRUE);
  /* We can ignore the return value from jpeg_read_header since
   *   (a) suspension is not possible with the stdio data source, and
   *   (b) we passed TRUE to reject a tables-only JPEG file as an error.
   * See libjpeg.doc for more info.
   */

  /* Step 4: set parameters for decompression */

  /* In this example, we don't need to change any of the defaults set by
   * jpeg_read_header(), so we do nothing here.
   */

  /* Step 5: Start decompressor */

  (void) jpeg_start_decompress(&cinfo);
  /* We can ignore the return value since suspension is not possible
   * with the stdio data source.
   */

  /* We may need to do some setup of our own at this point before reading
   * the data.  After jpeg_start_decompress() we have the correct scaled
   * output image dimensions available, as well as the output colormap
   * if we asked for color quantization.
   * In this example, we need to make an output work buffer of the right size.
   */ 
  /* JSAMPLEs per row in output buffer */
  row_stride = cinfo.output_width * cinfo.output_components;

  out = ri.Malloc(cinfo.output_width*cinfo.output_height*cinfo.output_components);

  *pic = out;
  *width = cinfo.output_width;
  *height = cinfo.output_height;

  /* Step 6: while (scan lines remain to be read) */
  /*           jpeg_read_scanlines(...); */

  /* Here we use the library's state variable cinfo.output_scanline as the
   * loop counter, so that we don't have to keep track ourselves.
   */
  while (cinfo.output_scanline < cinfo.output_height) {
    /* jpeg_read_scanlines expects an array of pointers to scanlines.
     * Here the array is only one element long, but you could ask for
     * more than one scanline at a time if that's more convenient.
     */
	bbuf = ((out+(row_stride*cinfo.output_scanline)));
	buffer = &bbuf;
    (void) jpeg_read_scanlines(&cinfo, buffer, 1);
  }

  // clear all the alphas to 255
  {
	  int	i, j;
		byte	*buf;

		buf = *pic;

	  j = cinfo.output_width * cinfo.output_height * 4;
	  for ( i = 3 ; i < j ; i+=4 ) {
		  buf[i] = 255;
	  }
  }

  /* Step 7: Finish decompression */

  (void) jpeg_finish_decompress(&cinfo);
  /* We can ignore the return value since suspension is not possible
   * with the stdio data source.
   */

  /* Step 8: Release JPEG decompression object */

  /* This is an important step since it will release a good deal of memory. */
  jpeg_destroy_decompress(&cinfo);