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