1/*
2 *
3 * Copyright © 2002 Keith Packard, member of The XFree86 Project, Inc.
4 *
5 * Permission to use, copy, modify, distribute, and sell this software and its
6 * documentation for any purpose is hereby granted without fee, provided that
7 * the above copyright notice appear in all copies and that both that
8 * copyright notice and this permission notice appear in supporting
9 * documentation, and that the name of Keith Packard not be used in
10 * advertising or publicity pertaining to distribution of the software without
11 * specific, written prior permission.  Keith Packard makes no
12 * representations about the suitability of this software for any purpose.  It
13 * is provided "as is" without express or implied warranty.
14 *
15 * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
16 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
17 * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
18 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
19 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
20 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
21 * PERFORMANCE OF THIS SOFTWARE.
22 */
23
24#ifdef HAVE_DIX_CONFIG_H
25#include <dix-config.h>
26#endif
27
28#include "scrnintstr.h"
29#include "gcstruct.h"
30#include "pixmapstr.h"
31#include "windowstr.h"
32#include "servermd.h"
33#include "mi.h"
34#include "picturestr.h"
35#include "mipict.h"
36
37static xFixed
38miLineFixedX(xLineFixed * l, xFixed y, Bool ceil)
39{
40    xFixed dx = l->p2.x - l->p1.x;
41    xFixed_32_32 ex = (xFixed_32_32) (y - l->p1.y) * dx;
42    xFixed dy = l->p2.y - l->p1.y;
43
44    if (ceil)
45        ex += (dy - 1);
46    return l->p1.x + (xFixed) (ex / dy);
47}
48
49void
50miTrapezoidBounds(int ntrap, xTrapezoid * traps, BoxPtr box)
51{
52    box->y1 = MAXSHORT;
53    box->y2 = MINSHORT;
54    box->x1 = MAXSHORT;
55    box->x2 = MINSHORT;
56    for (; ntrap; ntrap--, traps++) {
57        INT16 x1, y1, x2, y2;
58
59        if (!xTrapezoidValid(traps))
60            continue;
61        y1 = xFixedToInt(traps->top);
62        if (y1 < box->y1)
63            box->y1 = y1;
64
65        y2 = xFixedToInt(xFixedCeil(traps->bottom));
66        if (y2 > box->y2)
67            box->y2 = y2;
68
69        x1 = xFixedToInt(min(miLineFixedX(&traps->left, traps->top, FALSE),
70                             miLineFixedX(&traps->left, traps->bottom, FALSE)));
71        if (x1 < box->x1)
72            box->x1 = x1;
73
74        x2 = xFixedToInt(xFixedCeil
75                         (max
76                          (miLineFixedX(&traps->right, traps->top, TRUE),
77                           miLineFixedX(&traps->right, traps->bottom, TRUE))));
78        if (x2 > box->x2)
79            box->x2 = x2;
80    }
81}
82