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

*/
// d_clear: clears a specified rectangle to the specified color

#include "quakedef.h"


/*
================
D_FillRect
================
*/
void D_FillRect(vrect_t *rect, int color)
{
    int				rx, ry, rwidth, rheight;
    pixel_t			*dest;
    pixel_t			*ldest;

    rx = rect->x;
    ry = rect->y;
    rwidth = rect->width;
    rheight = rect->height;

    if (rx < 0) {
        rwidth += rx;
        rx = 0;
    }
    if (ry < 0) {
        rheight += ry;
        ry = 0;
    }
    if (rx+rwidth > vid.width) {
        rwidth = vid.width - rx;
    }
    if (ry+rheight > vid.height) {
        rheight = vid.height - rx;
    }

    if (rwidth < 1 || rheight < 1) {
        return;
    }

    dest = vid.buffer + ry*vid.width + rx;

    if (((rwidth & 0x03) == 0) && (((long)dest & 0x03) == 0)) {
        // faster aligned dword clear
        ldest = (unsigned *)dest;
        color += color << 16;

        rwidth >>= 2;
        color += color << 8;

        for (ry=0 ; ry<rheight ; ry++) {
            for (rx=0 ; rx<rwidth ; rx++) {
                ldest[rx] = color;
            }
            ldest = ldest + vid.rowbytes;
        }
    } else {
        // slower byte-by-byte clear for unaligned cases
        for (ry=0 ; ry<rheight ; ry++) {
            for (rx=0 ; rx<rwidth ; rx++) {
                dest[rx] = color;
            }
            dest += vid.width;
        }
    }
}

