| 0,0 → 1,112 |
|---|
| /* |
| * Copyright (C) 2006 Ondrej Palkovsky |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * - Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * - The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include <types.h> |
| #include <errno.h> |
| |
| #include "ppm.h" |
| |
| static void skip_whitespace(unsigned char **data) |
| { |
| retry: |
| while (**data == ' ' || **data == '\t' || **data == '\n' || **data == '\r') |
| (*data)++; |
| if (**data == '#') { |
| while (1) { |
| if (**data == '\n' || **data == '\r') |
| break; |
| (*data)++; |
| } |
| goto retry; |
| } |
| } |
| |
| static void read_num(unsigned char **data, unsigned int *num) |
| { |
| *num = 0; |
| while (**data >= '0' && **data <= '9') { |
| *num *= 10; |
| *num += **data - '0'; |
| (*data)++; |
| } |
| } |
| |
| /** Draw PPM pixmap |
| * |
| * @param data Pointer to PPM data |
| * @param datasz Maximum data size |
| * @param x Coordinate of upper left corner |
| * @param y Coordinate of upper left corner |
| * @param maxwidth Maximum allowed width for picture |
| * @param maxheight Maximum allowed height for picture |
| * @param putpixel Putpixel function used to print bitmap |
| */ |
| int draw_ppm(unsigned char *data, size_t datasz, unsigned int sx, |
| unsigned int sy, |
| unsigned int maxwidth, unsigned int maxheight, |
| void (*putpixel)(int,unsigned int, unsigned int, int),int vp) |
| { |
| unsigned int width, height; |
| unsigned int maxcolor; |
| int i; |
| void *maxdatap = data + datasz; |
| unsigned int color; |
| unsigned int coef; |
| |
| /* Read magic */ |
| if (data[0] != 'P' || data[1] != '6') |
| return EINVAL; |
| |
| data+=2; |
| skip_whitespace(&data); |
| read_num(&data, &width); |
| skip_whitespace(&data); |
| read_num(&data,&height); |
| skip_whitespace(&data); |
| read_num(&data,&maxcolor); |
| data++; |
| |
| if (maxcolor == 0 || maxcolor > 255 || width*height > datasz) { |
| return EINVAL; |
| } |
| coef = 255/maxcolor; |
| if (coef*maxcolor > 255) |
| coef -= 1; |
| |
| for (i=0; i < width*height; i++) { |
| /* Crop picture if we don't fit into region */ |
| if (i % width > maxwidth || i/width > maxheight) { |
| data += 3; |
| continue; |
| } |
| color = ((data[0]*coef) << 16) + ((data[1]*coef) << 8) + data[0]*coef; |
| |
| (*putpixel)(vp, sx+(i % width), sy+(i / width), color); |
| data += 3; |
| } |
| } |