quakeforge/libs/models/alias/floodfill.c

/*
	mod_flood.c

	Flood fill a skin texture.

	Copyright (C) 1996-1997  Id Software, Inc.

	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License
	as published by the Free Software Foundation; either version 2
	of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

	See the GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

*/
// models are the only shared resource between a client and server running
// on the same machine.

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

static __attribute__ ((used)) const char rcsid[] = "$Id$";

#include "QF/sys.h"
#include "QF/vid.h"

#include "mod_internal.h"

// a pose is a single set of vertexes.  a frame may be
// an animating sequence of poses

typedef struct {
	short		x, y;
} floodfill_t;

// must be a power of 2
#define FLOODFILL_FIFO_SIZE 0x1000
#define FLOODFILL_FIFO_MASK (FLOODFILL_FIFO_SIZE - 1)

#define FLOODFILL_STEP( off, dx, dy ) \
{ \
	if (pos[off] == fillcolor) { \
		pos[off] = 255; \
		fifo[inpt].x = x + (dx), fifo[inpt].y = y + (dy); \
		inpt = (inpt + 1) & FLOODFILL_FIFO_MASK; \
	} else if (pos[off] != 255) \
		fdc = pos[off]; \
}

/*
	Mod_FloodFillSkin

	Fill background pixels so mipmapping doesn't have halos - Ed
*/
VISIBLE void
Mod_FloodFillSkin (byte * skin, int skinwidth, int skinheight)
{
	byte        fillcolor = *skin;		// assume this is the pixel to fill
	floodfill_t fifo[FLOODFILL_FIFO_SIZE];
	int			filledcolor = -1, inpt = 0, outpt = 0;
	int         i;

	if (filledcolor == -1) {
		filledcolor = 0;
		// attempt to find opaque black
		for (i = 0; i < 256; ++i)
			if (d_8to24table[i] == (255 << 0))	// alpha 1.0
			{
				filledcolor = i;
				break;
			}
	}
	// can't fill to filled color or transparent color (used as visited marker)
	if ((fillcolor == filledcolor) || (fillcolor == 255)) {
		Sys_MaskPrintf (SYS_GLT, "not filling skin from %d to %d\n",
						fillcolor, filledcolor);
		return;
	}

	fifo[inpt].x = 0, fifo[inpt].y = 0;
	inpt = (inpt + 1) & FLOODFILL_FIFO_MASK;

	while (outpt != inpt) {
		int		x = fifo[outpt].x, y = fifo[outpt].y, fdc = filledcolor;
		byte   *pos = &skin[x + skinwidth * y];

		outpt = (outpt + 1) & FLOODFILL_FIFO_MASK;

		if (x > 0)
			FLOODFILL_STEP (-1, -1, 0);
		if (x < skinwidth - 1)
			FLOODFILL_STEP (1, 1, 0);
		if (y > 0)
			FLOODFILL_STEP (-skinwidth, 0, -1);
		if (y < skinheight - 1)
			FLOODFILL_STEP (skinwidth, 0, 1);
		skin[x + skinwidth * y] = fdc;
	}
}