Subversion Repositories HelenOS

Rev

Rev 3386 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1547 palkovsky 1
/*
2071 jermar 2
 * Copyright (c) 2006 Ondrej Palkovsky
1547 palkovsky 3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
28
 
2541 jermar 29
#include <sys/types.h>
1547 palkovsky 30
#include <errno.h>
31
 
32
#include "ppm.h"
33
 
34
static void skip_whitespace(unsigned char **data)
35
{
36
retry:
2541 jermar 37
    while (**data == ' ' || **data == '\t' || **data == '\n' ||
38
        **data == '\r')
1547 palkovsky 39
        (*data)++;
40
    if (**data == '#') {
41
        while (1) {
42
            if (**data == '\n' || **data == '\r')
43
                break;
44
            (*data)++;
45
        }
46
        goto retry;
47
    }
48
}
49
 
50
static void read_num(unsigned char **data, unsigned int *num)
51
{
52
    *num = 0;
53
    while (**data >= '0' && **data <= '9') {
54
        *num *= 10;
55
        *num += **data - '0';
56
        (*data)++;
57
    }
58
}
59
 
2541 jermar 60
int ppm_get_data(unsigned char *data, size_t dtsz, unsigned int *width,
61
    unsigned int *height)
1555 palkovsky 62
{
63
    /* Read magic */
64
    if (data[0] != 'P' || data[1] != '6')
65
        return EINVAL;
66
 
67
    data+=2;
68
    skip_whitespace(&data);
69
    read_num(&data, width);
70
    skip_whitespace(&data);
71
    read_num(&data,height);
72
 
73
    return 0;
74
}
75
 
1547 palkovsky 76
/** Draw PPM pixmap
77
 *
78
 * @param data Pointer to PPM data
79
 * @param datasz Maximum data size
1709 jermar 80
 * @param sx Coordinate of upper left corner
81
 * @param sy Coordinate of upper left corner
1547 palkovsky 82
 * @param maxwidth Maximum allowed width for picture
83
 * @param maxheight Maximum allowed height for picture
84
 * @param putpixel Putpixel function used to print bitmap
85
 */
2541 jermar 86
int ppm_draw(unsigned char *data, size_t datasz, unsigned int sx,
87
    unsigned int sy, unsigned int maxwidth, unsigned int maxheight,
88
    putpixel_cb_t putpixel, void *vport)
1547 palkovsky 89
{
90
    unsigned int width, height;
91
    unsigned int maxcolor;
92
    int i;
93
    unsigned int color;
94
    unsigned int coef;
4153 mejdrech 95
 
1547 palkovsky 96
    /* Read magic */
4153 mejdrech 97
    if ((data[0] != 'P') || (data[1] != '6'))
1547 palkovsky 98
        return EINVAL;
4153 mejdrech 99
 
100
    data += 2;
1547 palkovsky 101
    skip_whitespace(&data);
102
    read_num(&data, &width);
103
    skip_whitespace(&data);
4153 mejdrech 104
    read_num(&data, &height);
1547 palkovsky 105
    skip_whitespace(&data);
4153 mejdrech 106
    read_num(&data, &maxcolor);
1547 palkovsky 107
    data++;
4153 mejdrech 108
 
109
    if ((maxcolor == 0) || (maxcolor > 255) || (width * height > datasz))
1547 palkovsky 110
        return EINVAL;
4153 mejdrech 111
 
2541 jermar 112
    coef = 255 / maxcolor;
113
    if (coef * maxcolor > 255)
1547 palkovsky 114
        coef -= 1;
115
 
2541 jermar 116
    for (i = 0; i < width * height; i++) {
1547 palkovsky 117
        /* Crop picture if we don't fit into region */
2541 jermar 118
        if (i % width > maxwidth || i / width > maxheight) {
1547 palkovsky 119
            data += 3;
120
            continue;
121
        }
2541 jermar 122
        color = ((data[0] * coef) << 16) + ((data[1] * coef) << 8) +
123
            data[2] * coef;
1547 palkovsky 124
 
2541 jermar 125
        (*putpixel)(vport, sx + (i % width), sy + (i / width), color);
1547 palkovsky 126
        data += 3;
127
    }
4153 mejdrech 128
 
1720 palkovsky 129
    return 0;
1547 palkovsky 130
}