1 /*
2 
3 Copyright 1990, 1994, 1998  The Open Group
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.
10 
11 The above copyright notice and this permission notice shall be included in
12 all copies or substantial portions of the Software.
13 
14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
17 OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
18 AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
19 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
20 
21 Except as contained in this notice, the name of The Open Group shall not be
22 used in advertising or otherwise to promote the sale, use or other dealings
23 in this Software without prior written authorization from The Open Group.
24 
25 */
26 /* $XFree86: xc/lib/font/util/utilbitmap.c,v 1.3 1999/08/22 08:58:58 dawes Exp $ */
27 
28 /*
29  * Author:  Keith Packard, MIT X Consortium
30  */
31 
32 /* Modified for use with FreeType */
33 
34 
35 #include <ft2build.h>
36 #include "pcfutil.h"
37 
38 
39   /*
40    *  Invert bit order within each BYTE of an array.
41    */
42 
43   FT_LOCAL_DEF( void )
44   BitOrderInvert( unsigned char*  buf,
45                   size_t          nbytes )
46   {
47     for ( ; nbytes > 0; nbytes--, buf++ )
48     {
49       unsigned int  val = *buf;
50 
51 
52       val = ( ( val >> 1 ) & 0x55 ) | ( ( val << 1 ) & 0xAA );
53       val = ( ( val >> 2 ) & 0x33 ) | ( ( val << 2 ) & 0xCC );
54       val = ( ( val >> 4 ) & 0x0F ) | ( ( val << 4 ) & 0xF0 );
55 
56       *buf = (unsigned char)val;
57     }
58   }
59 
60 
61   /*
62    *  Invert byte order within each 16-bits of an array.
63    */
64 
65   FT_LOCAL_DEF( void )
66   TwoByteSwap( unsigned char*  buf,
67                size_t          nbytes )
68   {
69     for ( ; nbytes >= 2; nbytes -= 2, buf += 2 )
70     {
71       unsigned char  c;
72 
73 
74       c      = buf[0];
75       buf[0] = buf[1];
76       buf[1] = c;
77     }
78   }
79 
80   /*
81    *  Invert byte order within each 32-bits of an array.
82    */
83 
84   FT_LOCAL_DEF( void )
85   FourByteSwap( unsigned char*  buf,
86                 size_t          nbytes )
87   {
88     for ( ; nbytes >= 4; nbytes -= 4, buf += 4 )
89     {
90       unsigned char  c;
91 
92 
93       c      = buf[0];
94       buf[0] = buf[3];
95       buf[3] = c;
96 
97       c      = buf[1];
98       buf[1] = buf[2];
99       buf[2] = c;
100     }
101   }
102 
103 
104 /* END */
105