tr_image.c

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  /* After finish_decompress, we can close the input file.
   * Here we postpone it until after no more JPEG errors are possible,
   * so as to simplify the setjmp error logic above.  (Actually, I don't
   * think that jpeg_destroy can do an error exit, but why assume anything...)
   */
  ri.FS_FreeFile (fbuffer);

  /* At this point you may want to check to see whether any corrupt-data
   * warnings occurred (test whether jerr.pub.num_warnings is nonzero).
   */

  /* And we're done! */
}


/* Expanded data destination object for stdio output */

typedef struct {
  struct jpeg_destination_mgr pub; /* public fields */

  byte* outfile;		/* target stream */
  int	size;
} my_destination_mgr;

typedef my_destination_mgr * my_dest_ptr;


/*
 * Initialize destination --- called by jpeg_start_compress
 * before any data is actually written.
 */

void init_destination (j_compress_ptr cinfo)
{
  my_dest_ptr dest = (my_dest_ptr) cinfo->dest;

  dest->pub.next_output_byte = dest->outfile;
  dest->pub.free_in_buffer = dest->size;
}


/*
 * Empty the output buffer --- called whenever buffer fills up.
 *
 * In typical applications, this should write the entire output buffer
 * (ignoring the current state of next_output_byte & free_in_buffer),
 * reset the pointer & count to the start of the buffer, and return TRUE
 * indicating that the buffer has been dumped.
 *
 * In applications that need to be able to suspend compression due to output
 * overrun, a FALSE return indicates that the buffer cannot be emptied now.
 * In this situation, the compressor will return to its caller (possibly with
 * an indication that it has not accepted all the supplied scanlines).  The
 * application should resume compression after it has made more room in the
 * output buffer.  Note that there are substantial restrictions on the use of
 * suspension --- see the documentation.
 *
 * When suspending, the compressor will back up to a convenient restart point
 * (typically the start of the current MCU). next_output_byte & free_in_buffer
 * indicate where the restart point will be if the current call returns FALSE.
 * Data beyond this point will be regenerated after resumption, so do not
 * write it out when emptying the buffer externally.
 */

boolean empty_output_buffer (j_compress_ptr cinfo)
{
  return TRUE;
}


/*
 * Compression initialization.
 * Before calling this, all parameters and a data destination must be set up.
 *
 * We require a write_all_tables parameter as a failsafe check when writing
 * multiple datastreams from the same compression object.  Since prior runs
 * will have left all the tables marked sent_table=TRUE, a subsequent run
 * would emit an abbreviated stream (no tables) by default.  This may be what
 * is wanted, but for safety's sake it should not be the default behavior:
 * programmers should have to make a deliberate choice to emit abbreviated
 * images.  Therefore the documentation and examples should encourage people
 * to pass write_all_tables=TRUE; then it will take active thought to do the
 * wrong thing.
 */

GLOBAL void
jpeg_start_compress (j_compress_ptr cinfo, boolean write_all_tables)
{
  if (cinfo->global_state != CSTATE_START)
    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

  if (write_all_tables)
    jpeg_suppress_tables(cinfo, FALSE);	/* mark all tables to be written */

  /* (Re)initialize error mgr and destination modules */
  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
  (*cinfo->dest->init_destination) (cinfo);
  /* Perform master selection of active modules */
  jinit_compress_master(cinfo);
  /* Set up for the first pass */
  (*cinfo->master->prepare_for_pass) (cinfo);
  /* Ready for application to drive first pass through jpeg_write_scanlines
   * or jpeg_write_raw_data.
   */
  cinfo->next_scanline = 0;
  cinfo->global_state = (cinfo->raw_data_in ? CSTATE_RAW_OK : CSTATE_SCANNING);
}


/*
 * Write some scanlines of data to the JPEG compressor.
 *
 * The return value will be the number of lines actually written.
 * This should be less than the supplied num_lines only in case that
 * the data destination module has requested suspension of the compressor,
 * or if more than image_height scanlines are passed in.
 *
 * Note: we warn about excess calls to jpeg_write_scanlines() since
 * this likely signals an application programmer error.  However,
 * excess scanlines passed in the last valid call are *silently* ignored,
 * so that the application need not adjust num_lines for end-of-image
 * when using a multiple-scanline buffer.
 */

GLOBAL JDIMENSION
jpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines,
		      JDIMENSION num_lines)
{
  JDIMENSION row_ctr, rows_left;

  if (cinfo->global_state != CSTATE_SCANNING)
    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
  if (cinfo->next_scanline >= cinfo->image_height)
    WARNMS(cinfo, JWRN_TOO_MUCH_DATA);

  /* Call progress monitor hook if present */
  if (cinfo->progress != NULL) {
    cinfo->progress->pass_counter = (long) cinfo->next_scanline;
    cinfo->progress->pass_limit = (long) cinfo->image_height;
    (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
  }

  /* Give master control module another chance if this is first call to
   * jpeg_write_scanlines.  This lets output of the frame/scan headers be
   * delayed so that application can write COM, etc, markers between
   * jpeg_start_compress and jpeg_write_scanlines.
   */
  if (cinfo->master->call_pass_startup)
    (*cinfo->master->pass_startup) (cinfo);

  /* Ignore any extra scanlines at bottom of image. */
  rows_left = cinfo->image_height - cinfo->next_scanline;
  if (num_lines > rows_left)
    num_lines = rows_left;

  row_ctr = 0;
  (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, num_lines);
  cinfo->next_scanline += row_ctr;
  return row_ctr;
}

/*
 * Terminate destination --- called by jpeg_finish_compress
 * after all data has been written.  Usually needs to flush buffer.
 *
 * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
 * application must deal with any cleanup that should happen even
 * for error exit.
 */

static int hackSize;

void term_destination (j_compress_ptr cinfo)
{
  my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
  size_t datacount = dest->size - dest->pub.free_in_buffer;
  hackSize = datacount;
}


/*
 * Prepare for output to a stdio stream.
 * The caller must have already opened the stream, and is responsible
 * for closing it after finishing compression.
 */

void jpegDest (j_compress_ptr cinfo, byte* outfile, int size)
{
  my_dest_ptr dest;

  /* The destination object is made permanent so that multiple JPEG images
   * can be written to the same file without re-executing jpeg_stdio_dest.
   * This makes it dangerous to use this manager and a different destination
   * manager serially with the same JPEG object, because their private object
   * sizes may be different.  Caveat programmer.
   */
  if (cinfo->dest == NULL) {	/* first time for this JPEG object? */
    cinfo->dest = (struct jpeg_destination_mgr *)
      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
				  sizeof(my_destination_mgr));
  }

  dest = (my_dest_ptr) cinfo->dest;
  dest->pub.init_destination = init_destination;
  dest->pub.empty_output_buffer = empty_output_buffer;
  dest->pub.term_destination = term_destination;
  dest->outfile = outfile;
  dest->size = size;
}

void SaveJPG(char * filename, int quality, int image_width, int image_height, unsigned char *image_buffer) {
  /* This struct contains the JPEG compression parameters and pointers to
   * working space (which is allocated as needed by the JPEG library).
   * It is possible to have several such structures, representing multiple
   * compression/decompression processes, in existence at once.  We refer
   * to any one struct (and its associated working data) as a "JPEG object".
   */
  struct jpeg_compress_struct cinfo;
  /* 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 */
  JSAMPROW row_pointer[1];	/* pointer to JSAMPLE row[s] */
  int row_stride;		/* physical row width in image buffer */
  unsigned char *out;

  /* Step 1: allocate and initialize JPEG compression 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 compression object. */
  jpeg_create_compress(&cinfo);

  /* Step 2: specify data destination (eg, a file) */
  /* Note: steps 2 and 3 can be done in either order. */

  /* Here we use the library-supplied code to send compressed data to a
   * stdio stream.  You can also write your own code to do something else.
   * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
   * requires it in order to write binary files.
   */
  out = ri.Hunk_AllocateTempMemory(image_width*image_height*4);
  jpegDest(&cinfo, out, image_width*image_height*4);

  /* Step 3: set parameters for compression */

  /* First we supply a description of the input image.
   * Four fields of the cinfo struct must be filled in:
   */
  cinfo.image_width = image_width; 	/* image width and height, in pixels */
  cinfo.image_height = image_height;
  cinfo.input_components = 4;		/* # of color components per pixel */
  cinfo.in_color_space = JCS_RGB; 	/* colorspace of input image */
  /* Now use the library's routine to set default compression parameters.
   * (You must set at least cinfo.in_color_space before calling this,
   * since the defaults depend on the source color space.)
   */
  jpeg_set_defaults(&cinfo);
  /* Now you can set any non-default parameters you wish to.
   * Here we just illustrate the use of quality (quantization table) scaling:
   */
  jpeg_set_quality(&cinfo, quality, TRUE /* limit to baseline-JPEG values */);

  /* Step 4: Start compressor */

  /* TRUE ensures that we will write a complete interchange-JPEG file.
   * Pass TRUE unless you are very sure of what you're doing.
   */
  jpeg_start_compress(&cinfo, TRUE);

  /* Step 5: while (scan lines remain to be written) */
  /*           jpeg_write_scanlines(...); */

  /* Here we use the library's state variable cinfo.next_scanline as the
   * loop counter, so that we don't have to keep track ourselves.
   * To keep things simple, we pass one scanline per call; you can pass
   * more if you wish, though.
   */
  row_stride = image_width * 4;	/* JSAMPLEs per row in image_buffer */

  while (cinfo.next_scanline < cinfo.image_height) {
    /* jpeg_write_scanlines expects an array of pointers to scanlines.
     * Here the array is only one element long, but you could pass
     * more than one scanline at a time if that's more convenient.
     */
    row_pointer[0] = & image_buffer[((cinfo.image_height-1)*row_stride)-cinfo.next_scanline * row_stride];
    (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
  }

  /* Step 6: Finish compression */

  jpeg_finish_compress(&cinfo);
  /* After finish_compress, we can close the output file. */
  ri.FS_WriteFile( filename, out, hackSize );

  ri.Hunk_FreeTempMemory(out);

  /* Step 7: release JPEG compression object */

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

  /* And we're done! */
}

//===================================================================

/*
=================
R_LoadImage

Loads any of the supported image types into a cannonical
32 bit format.
=================
*/
void R_LoadImage( const char *name, byte **pic, int *width, int *height ) {
	int		len;

	*pic = NULL;
	*width = 0;
	*height = 0;

	len = strlen(name);
	if (len<5) {
		return;
	}

	if ( !Q_stricmp( name+len-4, ".tga" ) ) {
	  LoadTGA( name, pic, width, height );            // try tga first
    if (!*pic) {                                    //
		  char altname[MAX_QPATH];                      // try jpg in place of tga 
      strcpy( altname, name );                      
      len = strlen( altname );                  
      altname[len-3] = 'j';
      altname[len-2] = 'p';
      altname[len-1] = 'g';
			LoadJPG( altname, pic, width, height );
		}
  } else if ( !Q_stricmp(name+len-4, ".pcx") ) {
    LoadPCX32( name, pic, width, height );
	} else if ( !Q_stricmp( name+len-4, ".bmp" ) ) {
		LoadBMP( name, pic, width, height );
	} else if ( !Q_stricmp( name+len-4, ".jpg" ) ) {
		LoadJPG( name, pic, width, height );
	}
}


/*
===============
R_FindImageFile

Finds or loads the given image.
Returns NULL if it fails, not a default image.
==============
*/
image_t	*R_FindImageFile( const char *name, qboolean mipmap, qboolean allowPicmip, int glWrapClampMode ) {
	image_t	*image;
	int		width, height;
	byte	*pic;
	long	hash;

	if (!name) {
		return NULL;
	}

	hash = generateHashValue(name);

	//
	// see if the image is already loaded
	//
	for (image=hashTable[hash]; image; image=image->next) {
		if ( !strcmp( name, image->imgName ) ) {
			// the white image can be used with any set of parms, but other mismatches are errors
			if ( strcmp( name, "*white" ) ) {
				if ( image->mipmap != mipmap ) {
					ri.Printf( PRINT_DEVELOPER, "WARNING: reused image %s with mixed mipmap parm\n", name );
				}
				if ( image->allowPicmip != allowPicmip ) {
					ri.Printf( PRINT_DEVELOPER, "WARNING: reused image %s with mixed allowPicmip parm\n", name );
				}
				if ( image->wrapClampMode != glWrapClampMode ) {
					ri.Printf( PRINT_ALL, "WARNING: reused image %s with mixed glWrapClampMode parm\n", name );
				}
			}
			return image;
		}
	}

	//
	// load the pic from disk
	//
	R_LoadImage( name, &pic, &width, &height );
	if ( pic == NULL ) {                                    // if we dont get a successful load
	  char altname[MAX_QPATH];                              // copy the name
    int len;                                              //  
    strcpy( altname, name );                              //
    len = strlen( altname );                              // 
    altname[len-3] = toupper(altname[len-3]);             // and try upper case extension for unix systems
    altname[len-2] = toupper(altname[len-2]);             //
    altname[len-1] = toupper(altname[len-1]);             //
		ri.Printf( PRINT_ALL, "trying %s...\n", altname );    // 
	  R_LoadImage( altname, &pic, &width, &height );        //
    if (pic == NULL) {                                    // if that fails
      return NULL;                                        // bail
    }
	}

	image = R_CreateImage( ( char * ) name, pic, width, height, mipmap, allowPicmip, glWrapClampMode );
	ri.Free( pic );
	return image;
}


/*
================
R_CreateDlightImage
================
*/
#define	DLIGHT_SIZE	16
static void R_CreateDlightImage( void ) {
	int		x,y;
	byte	data[DLIGHT_SIZE][DLIGHT_SIZE][4];
	int		b;

	// make a centered inverse-square falloff blob for dynamic lighting
	for (x=0 ; x<DLIGHT_SIZE ; x++) {
		for (y=0 ; y<DLIGHT_SIZE ; y++) {
			float	d;

			d = ( DLIGHT_SIZE/2 - 0.5f - x ) * ( DLIGHT_SIZE/2 - 0.5f - x ) +
				( DLIGHT_SIZE/2 - 0.5f - y ) * ( DLIGHT_SIZE/2 - 0.5f - y );
			b = 4000 / d;
			if (b > 255) {
				b = 255;
			} else if ( b < 75 ) {
				b = 0;
			}
			data[y][x][0] = 
			data[y][x][1] = 
			data[y][x][2] = b;
			data[y][x][3] = 255;			
		}
	}
	tr.dlightImage = R_CreateImage("*dlight", (byte *)data, DLIGHT_SIZE, DLIGHT_SIZE, qfalse, qfalse, GL_CLAMP );
}


/*
=================
R_InitFogTable
=================
*/
void R_InitFogTable( void ) {
	int		i;
	float	d;
	float	exp;
	
	exp = 0.5;

	for ( i = 0 ; i < FOG_TABLE_SIZE ; i++ ) {
		d = pow ( (float)i/(FOG_TABLE_SIZE-1), exp );

		tr.fogTable[i] = d;
	}
}

/*
================
R_FogFactor

Returns a 0.0 to 1.0 fog density value
This is called for each texel of the fog texture on startup
and for each vertex of transparent shaders in fog dynamically
================
*/
float	R_FogFactor( float s, float t ) {
	float	d;

	s -= 1.0/512;
	if ( s < 0 ) {
		return 0;
	}
	if ( t < 1.0/32 ) {
		return 0;