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/* |
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* pngrender.c |
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*/ |
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|
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/* |
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________________________________________________________________________________ |
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|
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Copyright (c) 2001 James Bursa |
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|
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All rights reserved. |
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|
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Permission is hereby granted, free of charge, to any person obtaining a |
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copy of this software and associated documentation files (the |
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"Software"), to deal in the Software without restriction, including |
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without limitation the rights to use, copy, modify, merge, publish, |
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distribute, and/or sell copies of the Software, and to permit persons |
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to whom the Software is furnished to do so, provided that the above |
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copyright notice(s) and this permission notice appear in all copies of |
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the Software and that both the above copyright notice(s) and this |
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permission notice appear in supporting documentation. |
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|
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
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OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
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MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT |
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OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR |
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HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL |
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INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING |
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FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, |
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NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION |
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WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
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|
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Except as contained in this notice, the name of a copyright holder |
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shall not be used in advertising or otherwise to promote the sale, use |
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or other dealings in this Software without prior written authorization |
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of the copyright holder. |
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|
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________________________________________________________________________________ |
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|
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james.bursa@strcprstskrzkrk.co.uk |
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http://www.strcprstskrzkrk.co.uk/ |
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|
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________________________________________________________________________________ |
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*/ |
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|
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#include <stdio.h> |
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#include <stdlib.h> |
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|
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#include <png.h> |
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|
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#include <colourtrans.h> |
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#include <os.h> |
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|
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/********************************************************************************/ |
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|
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int render_png_file(const char *path, signed int x, signed int y); |
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int load_png_file(png_struct *png, png_info *info, const char *path); |
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int render_png_to_screen(png_struct *png, png_info *info, signed int value_list[], |
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signed int x, signed int y); |
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void png_render_32(png_byte *prows[], unsigned char *srow, signed int x0, |
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signed int y0, signed int x1, signed int y1, signed int sx, |
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unsigned int sline_length, unsigned int pchannels); |
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void png_render_16(png_byte *prows[], unsigned char *srow, signed int x0, |
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signed int y0, signed int x1, signed int y1, signed int sx, |
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unsigned int sline_length, unsigned int pchannels); |
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int png_render_8(png_byte *prows[], unsigned char *srow, signed int x0, |
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signed int y0, signed int x1, signed int y1, signed int sx, |
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unsigned int sline_length, unsigned int pchannels); |
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int png_render_4(png_byte *prows[], unsigned char *srow, signed int x0, |
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signed int y0, signed int x1, signed int y1, signed int sx, |
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unsigned int sline_length, unsigned int pchannels); |
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os_palette *read_palette(); |
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|
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/********************************************************************************/ |
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|
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float alpha_table[] = { |
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0.0, 1.0/255, 2.0/255, 3.0/255, 4.0/255, 5.0/255, |
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6.0/255, 7.0/255, 8.0/255, 9.0/255, 10.0/255, 11.0/255, |
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12.0/255, 13.0/255, 14.0/255, 15.0/255, 16.0/255, 17.0/255, |
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18.0/255, 19.0/255, 20.0/255, 21.0/255, 22.0/255, 23.0/255, |
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24.0/255, 25.0/255, 26.0/255, 27.0/255, 28.0/255, 29.0/255, |
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30.0/255, 31.0/255, 32.0/255, 33.0/255, 34.0/255, 35.0/255, |
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36.0/255, 37.0/255, 38.0/255, 39.0/255, 40.0/255, 41.0/255, |
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42.0/255, 43.0/255, 44.0/255, 45.0/255, 46.0/255, 47.0/255, |
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48.0/255, 49.0/255, 50.0/255, 51.0/255, 52.0/255, 53.0/255, |
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54.0/255, 55.0/255, 56.0/255, 57.0/255, 58.0/255, 59.0/255, |
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60.0/255, 61.0/255, 62.0/255, 63.0/255, 64.0/255, 65.0/255, |
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66.0/255, 67.0/255, 68.0/255, 69.0/255, 70.0/255, 71.0/255, |
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72.0/255, 73.0/255, 74.0/255, 75.0/255, 76.0/255, 77.0/255, |
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78.0/255, 79.0/255, 80.0/255, 81.0/255, 82.0/255, 83.0/255, |
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84.0/255, 85.0/255, 86.0/255, 87.0/255, 88.0/255, 89.0/255, |
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90.0/255, 91.0/255, 92.0/255, 93.0/255, 94.0/255, 95.0/255, |
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96.0/255, 97.0/255, 98.0/255, 99.0/255, 100.0/255, 101.0/255, |
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102.0/255, 103.0/255, 104.0/255, 105.0/255, 106.0/255, 107.0/255, |
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108.0/255, 109.0/255, 110.0/255, 111.0/255, 112.0/255, 113.0/255, |
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114.0/255, 115.0/255, 116.0/255, 117.0/255, 118.0/255, 119.0/255, |
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120.0/255, 121.0/255, 122.0/255, 123.0/255, 124.0/255, 125.0/255, |
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126.0/255, 127.0/255, 128.0/255, 129.0/255, 130.0/255, 131.0/255, |
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132.0/255, 133.0/255, 134.0/255, 135.0/255, 136.0/255, 137.0/255, |
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138.0/255, 139.0/255, 140.0/255, 141.0/255, 142.0/255, 143.0/255, |
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144.0/255, 145.0/255, 146.0/255, 147.0/255, 148.0/255, 149.0/255, |
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150.0/255, 151.0/255, 152.0/255, 153.0/255, 154.0/255, 155.0/255, |
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156.0/255, 157.0/255, 158.0/255, 159.0/255, 160.0/255, 161.0/255, |
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162.0/255, 163.0/255, 164.0/255, 165.0/255, 166.0/255, 167.0/255, |
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168.0/255, 169.0/255, 170.0/255, 171.0/255, 172.0/255, 173.0/255, |
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174.0/255, 175.0/255, 176.0/255, 177.0/255, 178.0/255, 179.0/255, |
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180.0/255, 181.0/255, 182.0/255, 183.0/255, 184.0/255, 185.0/255, |
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186.0/255, 187.0/255, 188.0/255, 189.0/255, 190.0/255, 191.0/255, |
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192.0/255, 193.0/255, 194.0/255, 195.0/255, 196.0/255, 197.0/255, |
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198.0/255, 199.0/255, 200.0/255, 201.0/255, 202.0/255, 203.0/255, |
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204.0/255, 205.0/255, 206.0/255, 207.0/255, 208.0/255, 209.0/255, |
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210.0/255, 211.0/255, 212.0/255, 213.0/255, 214.0/255, 215.0/255, |
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216.0/255, 217.0/255, 218.0/255, 219.0/255, 220.0/255, 221.0/255, |
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222.0/255, 223.0/255, 224.0/255, 225.0/255, 226.0/255, 227.0/255, |
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228.0/255, 229.0/255, 230.0/255, 231.0/255, 232.0/255, 233.0/255, |
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234.0/255, 235.0/255, 236.0/255, 237.0/255, 238.0/255, 239.0/255, |
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240.0/255, 241.0/255, 242.0/255, 243.0/255, 244.0/255, 245.0/255, |
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246.0/255, 247.0/255, 248.0/255, 249.0/255, 250.0/255, 251.0/255, |
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252.0/255, 253.0/255, 254.0/255, 1.0 }; |
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|
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/********************************************************************************/ |
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|
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int main(int argc, char *argv[]) |
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{ |
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char *end; |
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|
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if (argc != 4) |
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{ |
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fprintf(stderr, "Usage: pngrender file x y\n"); |
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exit(1); |
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} |
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|
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return render_png_file(argv[1], strtol(argv[2], &end, 10), strtol(argv[3], &end, 10)); |
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} |
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|
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/******************************************************************************** |
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* render a png file to the screen |
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* => path -- filename of png file to render |
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* x, y -- position of bottom-left corner in os units from screen bottom-left |
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* <= return code: |
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* 0 - OK |
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* -1 - file failed to open |
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* -2 - couldn't read header |
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* -3 - not a png |
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* -4 - bpp of png not understood |
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* -5 - malloc or colourtrans failed |
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* other - os error number from OS_ReadVduVariables |
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*/ |
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|
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int render_png_file(const char *path, signed int x, signed int y) |
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{ |
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unsigned int status; |
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signed int value_list[20]; |
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png_struct *png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); |
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png_info *info = png_create_info_struct(png); |
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const os_vdu_var var_list[] = {os_MODEVAR_LINE_LENGTH, os_MODEVAR_LOG2_BPP, |
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os_MODEVAR_XEIG_FACTOR, os_MODEVAR_YEIG_FACTOR, |
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os_VDUVAR_GWL_COL, os_VDUVAR_GWB_ROW, os_VDUVAR_GWR_COL, os_VDUVAR_GWT_ROW, |
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os_VDUVAR_ORGX, os_VDUVAR_ORGY, os_VDUVAR_SCREEN_START, |
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os_MODEVAR_YWIND_LIMIT, -1}; |
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os_error const *error; |
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|
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status = load_png_file(png, info, path); |
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if (status) |
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{ |
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png_destroy_read_struct(&png, &info, (png_info **) NULL); |
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return status; |
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} |
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|
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error = xos_read_vdu_variables((os_vdu_var_list *) &var_list, value_list); |
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if (error) |
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{ |
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png_destroy_read_struct(&png, &info, (png_info **) NULL); |
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return error->errnum; |
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} |
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|
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status = render_png_to_screen(png, info, value_list, x, y); |
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png_destroy_read_struct(&png, &info, (png_info **) NULL); |
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return status; |
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} |
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|
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/********************************************************************************/ |
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|
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int load_png_file(png_struct *png, png_info *info, const char *path) |
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{ |
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unsigned char buf[10]; |
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FILE *file; |
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|
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if (!(file = fopen(path, "rb"))) return -1; |
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if (fread(buf, 1, 8, file) < 8) return -2; |
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if (png_sig_cmp(buf, 0, 8) != 0) return -3; |
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|
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rewind(file); |
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|
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png_init_io(png, file); |
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png_read_png(png, info, |
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PNG_TRANSFORM_STRIP_16 // Strip 16-bit samples to 8 bits |
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| PNG_TRANSFORM_PACKING // Expand 1, 2 and 4-bit samples to bytes |
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| PNG_TRANSFORM_EXPAND // Perform set_expand() |
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, NULL); |
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|
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fclose(file); |
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|
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return 0; |
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} |
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|
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/********************************************************************************/ |
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|
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int render_png_to_screen(png_struct *png, png_info *info, signed int value_list[], |
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signed int sx, signed int sy) |
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{ |
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unsigned char *srow; |
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unsigned int pwidth, pheight, pchannels, sbpp, sline_length, ox, oy; |
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signed int x0, y0, x1, y1; |
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png_byte **prows; |
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|
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pchannels = png_get_channels(png, info); /* png channels, including alpha */ |
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pwidth = png_get_image_width(png, info); /* png width / pixels */ |
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pheight = png_get_image_height(png, info); /* png height / pixels */ |
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prows = png_get_rows(png, info); /* array of png rows data */ |
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|
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sline_length = value_list[0]; /* screen line length / bytes */ |
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sbpp = 1 << value_list[1]; /* screen depth */ |
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|
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ox = value_list[8] >> value_list[2]; /* graphics origin / pixels */ |
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oy = value_list[9] >> value_list[2]; |
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sx = (sx >> value_list[2]) + ox; /* x / pixels */ |
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sy = (sy >> value_list[3]) + oy; /* y / pixels */ |
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|
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x0 = value_list[4] - sx; /* graphics window relative to */ |
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y0 = value_list[5] - sy; /* image origin / pixels */ |
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x1 = value_list[6] - sx; |
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y1 = value_list[7] - sy; |
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|
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if (x0 < 0) x0 = 0; /* region of image to render */ |
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if (y0 < 0) y0 = 0; |
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if (x1 >= pwidth) x1 = pwidth - 1; |
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if (y1 >= pheight) y1 = pheight - 1; |
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|
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if (x0 >= pwidth) return 0; /* outside graphics window */ |
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if (y0 >= pheight) return 0; |
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if (x1 < 0) return 0; |
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if (y1 < 0) return 0; |
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|
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srow = (unsigned char *) (value_list[10] + |
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(value_list[11] - sy - pheight + 1) * sline_length); |
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|
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switch (sbpp) |
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{ |
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case 32: |
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png_render_32(prows, srow, x0, pheight - 1 - y1, x1, pheight - 1 - y0, |
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sx, sline_length, pchannels); |
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break; |
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|
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case 16: |
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png_render_16(prows, srow, x0, pheight - 1 - y1, x1, pheight - 1 - y0, |
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sx, sline_length, pchannels); |
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break; |
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|
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case 8: |
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return png_render_8(prows, srow, x0, pheight - 1 - y1, x1, pheight - 1 - y0, |
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sx, sline_length, pchannels); |
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|
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case 4: |
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return png_render_4(prows, srow, x0, pheight - 1 - y1, x1, pheight - 1 - y0, |
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sx, sline_length, pchannels); |
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} |
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|
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return 0; |
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} |
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|
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/********************************************************************************/ |
| 272 |
|
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void png_render_32(png_byte *prows[], unsigned char *srow, signed int x0, |
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signed int y0, signed int x1, signed int y1, signed int sx, |
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unsigned int sline_length, unsigned int pchannels) |
| 276 |
{ |
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unsigned char pr, pg, pb, sr, sb, sg, *pbyte, *sbyte; |
| 278 |
unsigned int prow, pcol, palpha; |
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float alphaf, ialphaf; |
| 280 |
|
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for (prow = y0; prow <= y1; prow++) |
| 282 |
{ |
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pbyte = prows[prow] + (x0 * pchannels); |
| 284 |
sbyte = srow + sline_length * prow + (sx + x0) * 4; |
| 285 |
|
| 286 |
for (pcol = x0; pcol <= x1; pcol++) |
| 287 |
{ |
| 288 |
pr = *pbyte++; |
| 289 |
if (pchannels == 1 || pchannels == 2) pg = pb = pr; /* greyscale */ |
| 290 |
else { pg = *pbyte++; pb = *pbyte++; } /* colour */ |
| 291 |
|
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palpha = (pchannels == 4 || pchannels == 2 ? *pbyte++ : 255); |
| 293 |
|
| 294 |
if (palpha == 0) { sbyte += 4; continue; } /* fully transparent */ |
| 295 |
|
| 296 |
if (palpha != 255) /* partially transparent */ |
| 297 |
{ |
| 298 |
alphaf = alpha_table[palpha]; |
| 299 |
ialphaf = alpha_table[255 - palpha]; |
| 300 |
|
| 301 |
sr = *sbyte; sg = *(sbyte + 1); sb = *(sbyte + 2); |
| 302 |
|
| 303 |
pr = alphaf * pr + ialphaf * sr; |
| 304 |
pg = alphaf * pg + ialphaf * sg; |
| 305 |
pb = alphaf * pb + ialphaf * sb; |
| 306 |
} |
| 307 |
|
| 308 |
*sbyte++ = pr; *sbyte++ = pg; *sbyte++ = pb; sbyte++; |
| 309 |
} |
| 310 |
} |
| 311 |
} |
| 312 |
|
| 313 |
/********************************************************************************/ |
| 314 |
|
| 315 |
void png_render_16(png_byte *prows[], unsigned char *srow, signed int x0, |
| 316 |
signed int y0, signed int x1, signed int y1, signed int sx, |
| 317 |
unsigned int sline_length, unsigned int pchannels) |
| 318 |
{ |
| 319 |
unsigned char pr, pg, pb, sr, sb, sg, *pbyte, *sbyte; |
| 320 |
unsigned int prow, pcol, palpha; |
| 321 |
float alphaf, ialphaf; |
| 322 |
|
| 323 |
for (prow = y0; prow <= y1; prow++) |
| 324 |
{ |
| 325 |
pbyte = prows[prow] + (x0 * pchannels); |
| 326 |
sbyte = srow + sline_length * prow + (sx + x0) * 2; |
| 327 |
|
| 328 |
for (pcol = x0; pcol <= x1; pcol++) |
| 329 |
{ |
| 330 |
pr = *pbyte++ >> 3; |
| 331 |
if (pchannels == 1 || pchannels == 2) pg = pb = pr; |
| 332 |
else { pg = *pbyte++ >> 3; pb = *pbyte++ >> 3; } |
| 333 |
|
| 334 |
palpha = (pchannels == 4 || pchannels == 2 ? *pbyte++ : 255); |
| 335 |
|
| 336 |
if (palpha == 0) { sbyte += 2; continue; } |
| 337 |
|
| 338 |
if (palpha != 255) |
| 339 |
{ |
| 340 |
alphaf = alpha_table[palpha]; |
| 341 |
ialphaf = alpha_table[255 - palpha]; |
| 342 |
|
| 343 |
sr = *sbyte & 0x1f; |
| 344 |
sg = (*sbyte >> 5) | ((*(sbyte + 1) & 0x3) << 3); |
| 345 |
sb = (*(sbyte + 1) >> 2) & 0x1f; |
| 346 |
|
| 347 |
pr = alphaf * pr + ialphaf * sr; |
| 348 |
pg = alphaf * pg + ialphaf * sg; |
| 349 |
pb = alphaf * pb + ialphaf * sb; |
| 350 |
} |
| 351 |
|
| 352 |
*sbyte++ = (pg << 5) | pr; |
| 353 |
*sbyte++ = (pb << 2) | (pg >> 3); |
| 354 |
} |
| 355 |
} |
| 356 |
} |
| 357 |
|
| 358 |
/********************************************************************************/ |
| 359 |
|
| 360 |
int png_render_8(png_byte *prows[], unsigned char *srow, signed int x0, |
| 361 |
signed int y0, signed int x1, signed int y1, signed int sx, |
| 362 |
unsigned int sline_length, unsigned int pchannels) |
| 363 |
{ |
| 364 |
unsigned char pr, pg, pb, sr, sb, sg, *pbyte, *sbyte, map[0x1000]; |
| 365 |
unsigned int prow, pcol, palpha, colour; |
| 366 |
float alphaf, ialphaf; |
| 367 |
os_palette *palette; |
| 368 |
os_colour scolour; |
| 369 |
|
| 370 |
palette = read_palette(); |
| 371 |
if (!palette) return -5; |
| 372 |
|
| 373 |
for (colour = 0; colour < 0x1000; colour++) |
| 374 |
{ |
| 375 |
map[colour] = colourtrans_return_colour_number( |
| 376 |
((colour & 0xf) << 8) | /* red */ |
| 377 |
((colour & 0xf) << 12) | |
| 378 |
(((colour >> 4) & 0xf) << 16) | /* green */ |
| 379 |
(((colour >> 4) & 0xf) << 20) | |
| 380 |
(((colour >> 8) & 0xf) << 24) | /* blue */ |
| 381 |
(((colour >> 8) & 0xf) << 28)); |
| 382 |
} |
| 383 |
|
| 384 |
/* render image */ |
| 385 |
for (prow = y0; prow <= y1; prow++) |
| 386 |
{ |
| 387 |
pbyte = prows[prow] + (x0 * pchannels); |
| 388 |
sbyte = srow + sline_length * prow + sx + x0; |
| 389 |
|
| 390 |
for (pcol = x0; pcol <= x1; pcol++) |
| 391 |
{ |
| 392 |
pr = *pbyte++; |
| 393 |
if (pchannels == 1 || pchannels == 2) pg = pb = pr; |
| 394 |
else { pg = *pbyte++; pb = *pbyte++; } |
| 395 |
|
| 396 |
palpha = (pchannels == 4 || pchannels == 2 ? *pbyte++ : 255); |
| 397 |
|
| 398 |
if (palpha == 0) { sbyte++; continue; } |
| 399 |
|
| 400 |
if (palpha != 255) |
| 401 |
{ |
| 402 |
alphaf = alpha_table[palpha]; |
| 403 |
ialphaf = alpha_table[255 - palpha]; |
| 404 |
|
| 405 |
scolour = palette->entries[*sbyte]; |
| 406 |
sr = (scolour >> 8) & 0xff; |
| 407 |
sg = (scolour >> 16) & 0xff; |
| 408 |
sb = (scolour >> 24) & 0xff; |
| 409 |
|
| 410 |
pr = alphaf * pr + ialphaf * sr; |
| 411 |
pg = alphaf * pg + ialphaf * sg; |
| 412 |
pb = alphaf * pb + ialphaf * sb; |
| 413 |
} |
| 414 |
|
| 415 |
*sbyte++ = map[(pr >> 4) | (pg & 0xf0) | ((pb << 4) & 0xf00)]; |
| 416 |
} |
| 417 |
} |
| 418 |
|
| 419 |
free(palette); |
| 420 |
|
| 421 |
return 0; |
| 422 |
} |
| 423 |
|
| 424 |
/********************************************************************************/ |
| 425 |
|
| 426 |
int png_render_4(png_byte *prows[], unsigned char *srow, signed int x0, |
| 427 |
signed int y0, signed int x1, signed int y1, signed int sx, |
| 428 |
unsigned int sline_length, unsigned int pchannels) |
| 429 |
{ |
| 430 |
unsigned char pr, pg, pb, sr, sb, sg, *pbyte, *sbyte, map[0x1000]; |
| 431 |
unsigned int prow, pcol, palpha, spix, colour; |
| 432 |
float alphaf, ialphaf; |
| 433 |
os_palette *palette; |
| 434 |
os_colour scolour; |
| 435 |
|
| 436 |
palette = read_palette(); |
| 437 |
if (!palette) return -5; |
| 438 |
|
| 439 |
for (colour = 0; colour < 0x1000; colour++) |
| 440 |
{ |
| 441 |
map[colour] = colourtrans_return_colour_number( |
| 442 |
((colour & 0xf) << 8) | /* red */ |
| 443 |
((colour & 0xf) << 12) | |
| 444 |
(((colour >> 4) & 0xf) << 16) | /* green */ |
| 445 |
(((colour >> 4) & 0xf) << 20) | |
| 446 |
(((colour >> 8) & 0xf) << 24) | /* blue */ |
| 447 |
(((colour >> 8) & 0xf) << 28)); |
| 448 |
} |
| 449 |
|
| 450 |
/* render image */ |
| 451 |
for (prow = y0; prow <= y1; prow++) |
| 452 |
{ |
| 453 |
pbyte = prows[prow] + (x0 * pchannels); |
| 454 |
sbyte = srow + sline_length * prow + (sx + x0) / 2; |
| 455 |
spix = (sx + x0) & 1; |
| 456 |
|
| 457 |
for (pcol = x0; pcol <= x1; pcol++) |
| 458 |
{ |
| 459 |
pr = *pbyte++; |
| 460 |
if (pchannels == 1 || pchannels == 2) pg = pb = pr; |
| 461 |
else { pg = *pbyte++; pb = *pbyte++; } |
| 462 |
|
| 463 |
palpha = (pchannels == 4 || pchannels == 2 ? *pbyte++ : 255); |
| 464 |
|
| 465 |
if (palpha == 0) |
| 466 |
{ |
| 467 |
spix = 1 - spix; |
| 468 |
if (spix == 0) sbyte++; |
| 469 |
continue; |
| 470 |
} |
| 471 |
|
| 472 |
if (palpha != 255) |
| 473 |
{ |
| 474 |
alphaf = alpha_table[palpha]; |
| 475 |
ialphaf = alpha_table[255 - palpha]; |
| 476 |
|
| 477 |
scolour = (spix ? palette->entries[(*sbyte >> 4) & 0xf] |
| 478 |
: palette->entries[*sbyte & 0xf]); |
| 479 |
sr = (scolour >> 8) & 0xff; |
| 480 |
sg = (scolour >> 16) & 0xff; |
| 481 |
sb = (scolour >> 24) & 0xff; |
| 482 |
|
| 483 |
pr = alphaf * pr + ialphaf * sr; |
| 484 |
pg = alphaf * pg + ialphaf * sg; |
| 485 |
pb = alphaf * pb + ialphaf * sb; |
| 486 |
} |
| 487 |
|
| 488 |
*sbyte = (spix ? |
| 489 |
(map[(pr >> 4) | (pg & 0xf0) | ((pb << 4) & 0xf00)] << 4) | (*sbyte & 0xf) : |
| 490 |
map[(pr >> 4) | (pg & 0xf0) | ((pb << 4) & 0xf00)] | (*sbyte & 0xf0)); |
| 491 |
|
| 492 |
spix = 1 - spix; |
| 493 |
if (spix == 0) sbyte++; |
| 494 |
} |
| 495 |
} |
| 496 |
|
| 497 |
free(palette); |
| 498 |
|
| 499 |
return 0; |
| 500 |
} |
| 501 |
|
| 502 |
/******************************************************************************** |
| 503 |
* read screen palette |
| 504 |
*/ |
| 505 |
|
| 506 |
os_palette *read_palette() |
| 507 |
{ |
| 508 |
unsigned int size; |
| 509 |
os_palette *palette; |
| 510 |
os_error const *error; |
| 511 |
|
| 512 |
error = xcolourtrans_read_palette((osspriteop_area const *) -1, (osspriteop_id) -1, |
| 513 |
(os_palette *) 0, 0, 0, &size); |
| 514 |
if (error) return 0; |
| 515 |
|
| 516 |
palette = malloc(size); |
| 517 |
if (!palette) return 0; |
| 518 |
|
| 519 |
error = xcolourtrans_read_palette((osspriteop_area const *) -1, (osspriteop_id) -1, |
| 520 |
palette, size, 0, NULL); |
| 521 |
if (error) return 0; |
| 522 |
|
| 523 |
return palette; |
| 524 |
} |
| 525 |
|
| 526 |
/********************************************************************************/ |
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