hackthelobby/libcaca/tools/optipal.c

312 lines
12 KiB
C

/*
* optipal S-Lang optimised palette generator for libcaca
* Copyright (c) 2003-2012 Sam Hocevar <sam@hocevar.net>
* All Rights Reserved
*
*
* This program is free software. It comes without any warranty, to
* the extent permitted by applicable law. You can redistribute it
* and/or modify it under the terms of the Do What the Fuck You Want
* to Public License, Version 2, as published by Sam Hocevar. See
* http://www.wtfpl.net/ for more details.
*/
#include "config.h"
#if !defined(__KERNEL__)
# include <stdio.h>
#endif
#include "caca.h" /* Only necessary for CACA_* macros */
static void base_colors(void);
static void emulated_colors(void);
static void unused_colors(void);
static int slang_assoc[16*16], palette[16*16];
/* 6 colours in hue order */
static unsigned int const hue_list[] =
{
CACA_RED, CACA_BROWN, CACA_GREEN,
CACA_CYAN, CACA_BLUE, CACA_MAGENTA
};
#define SETPAIR(_fg, _bg, _n) \
do \
{ \
int fg = _fg, bg = _bg, n = _n; \
slang_assoc[fg + 16 * bg] = n; \
palette[n] = fg + 16 * bg; \
} \
while(0);
int main(int argc, char *argv[])
{
int i;
for(i = 0; i < 16 * 16; i++)
{
slang_assoc[i] = -1;
palette[i] = -1;
}
/* The base colour pairs (0-127) */
base_colors();
/* Now the less important pairs that we can afford to emulate using
* previously defined colour pairs. */
emulated_colors();
/* Fill the rest of the palette with equal colour pairs such as black
* on black. They will never be used, but nevermind. */
unused_colors();
/* Output the palette */
printf("static int const slang_palette[2*16*16] =\n{\n");
for(i = 0; i < 16 * 16; i++)
{
if((i % 8) == 0) printf(" ");
printf("%2i, %2i, ", palette[i] % 16, palette[i] / 16);
if((i % 8) == 7) printf("\n");
}
printf("};\n\n");
/* Output the association table */
printf("static int const slang_assoc[16*16] =\n{\n");
for(i = 0; i < 16 * 16; i++)
{
if((i % 16) == 0) printf(" ");
printf("%i, ", slang_assoc[i]);
if((i % 16) == 15) printf("\n");
}
printf("};\n");
return 0;
}
/*
* 256 character pairs are definable, but only 128 can be used. This is
* because slsmg.c's This_Color variable uses its 8th bit to indicate an
* alternate character set. Replacing a few 0x7F with 0xFF in sldisply.c
* works around the problem but gets rid of the alternate charset.
*
* We can work around this problem. See this usage grid:
*
* bg 1 1 1 1 1 1
* fg 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
*
* 0 (black) C C C C C C F B c c c c c c F
* 1 (blue) A h D h D i f C C h E h E k g
* 2 (green) A h D h i D f C h C E h k E g
* 3 (cyan) A D D i h h f C E E C k h h g
* 4 (red) A h h i D D f C h h k C E E g
* 5 (magenta) A D i h D h f C E k h E C h g
* 6 (brown) A i D h D h f C k E h E h C g
* 7 (light gray) A F a a a a a B C C C C C C B
*
* 8 (dark gray) A C C C C C C B d d d d d d F
* 9 (light blue) A C h E h E j C e h D h D l C
* 10 (light green) A h C E h j E C e h D h l D C
* 11 (light cyan) A E E C j h h C e D D l h h C
* 12 (light red) A h h j C E E C e h h l D D C
* 13 (light magenta) A E j h E C h C e D l h D h C
* 14 (yellow) A j E h E h C C e l D h D h C
* 15 (white) A F b b b b b B F C C C C C C
*
* ' ': useless colour pairs that can be emulated by printing a space in
* any other colour pair that has the same background
* 'A': black background colour pairs that are needed for the old renderer
* 'B': gray combinations used for grayscale dithering
* 'C': white/light, light/dark, lightgray/light, darkgray/dark, dark/black
* combinations often used for saturation/value dithering (the two
* other possible combinations, lightgray/dark and darkgray/light, are
* not considered here)
* 'D': next colour combinations for hue dithering (magenta/blue, blue/green
* and so on)
* 'E': next colour combinations for hue/value dithering (blue/lightgreen,
* green/lightblue and so on)
* 'F': black on light gray, black on white, white on dark gray, dark gray
* on white, white on blue, light gray on blue (chosen arbitrarily)
*
* 'A': 15 colour pairs
* 'A'+'B': 20 colour pairs
* 'A'+'B'+'C': 74 colour pairs
* 'A'+'B'+'C'+'D': 98 colour pairs
* 'A'+'B'+'C'+'D'+'E': 122 colour pairs
* 'A'+'B'+'C'+'D'+'E'+'F': 128 colour pairs
*
* The remaining slightly important colour pairs are:
*
* 'a': light gray on dark colour: emulate with light colour on dark colour
* 'b': white on dark colour: emulate with light gray on light colour
* 'c': black on light colour: emulate with dark gray on dark colour
* 'd': dark gray on light colour: emulate with dark colour on light colour
* 'e': light colour on dark gray: emulate with dark colour on dark gray
* 'f': dark colour on light gray: emulate with light colour on light gray
* 'g': dark colour on white: emulate with light colour on white
*
* And now the seldom used pairs:
*
* 'h': 120 degree hue pairs can be emulated as well; for instance blue on
* red can be emulated using magenta on red, and blue on green using
* cyan on green
*
* And the almost never used pairs:
*
* 'i': dark opposite on dark: emulate with dark opposite on black
* 'j': light opposite on dark: emulate with light opposite on black
* 'k': dark opposite on light: emulate with black on dark
* 'l': light opposite on light: emulate with white on light
*/
static void base_colors(void)
{
int i, cur = 0;
/* black background colour pairs that are needed for the old renderer */
for(i = 1; i < 16; i++)
SETPAIR(i, CACA_BLACK, cur++);
/* gray combinations used for grayscale dithering */
SETPAIR(CACA_BLACK, CACA_DARKGRAY, cur++);
SETPAIR(CACA_DARKGRAY, CACA_LIGHTGRAY, cur++);
SETPAIR(CACA_LIGHTGRAY, CACA_DARKGRAY, cur++);
SETPAIR(CACA_WHITE, CACA_LIGHTGRAY, cur++);
SETPAIR(CACA_LIGHTGRAY, CACA_WHITE, cur++);
/* white/light, light/dark, lightgray/light, darkgray/dark, dark/black
* combinations often used for saturation/value dithering (the two
* other possible combinations, lightgray/dark and darkgray/light, are
* not considered here) */
for(i = 1; i < 7; i++)
{
SETPAIR(CACA_WHITE, i + 8, cur++);
SETPAIR(i + 8, CACA_WHITE, cur++);
SETPAIR(i, i + 8, cur++);
SETPAIR(i + 8, i, cur++);
SETPAIR(CACA_LIGHTGRAY, i + 8, cur++);
SETPAIR(i + 8, CACA_LIGHTGRAY, cur++);
SETPAIR(CACA_DARKGRAY, i, cur++);
SETPAIR(i, CACA_DARKGRAY, cur++);
SETPAIR(CACA_BLACK, i, cur++);
}
/* next colour combinations for hue dithering (magenta/blue, blue/green
* and so on) */
for(i = 0; i < 6; i++)
{
SETPAIR(hue_list[i], hue_list[(i + 1) % 6], cur++);
SETPAIR(hue_list[(i + 1) % 6], hue_list[i], cur++);
SETPAIR(hue_list[i] + 8, hue_list[(i + 1) % 6] + 8, cur++);
SETPAIR(hue_list[(i + 1) % 6] + 8, hue_list[i] + 8, cur++);
}
/* next colour combinations for hue/value dithering (blue/lightgreen,
* green/lightblue and so on) */
for(i = 0; i < 6; i++)
{
SETPAIR(hue_list[i], hue_list[(i + 1) % 6] + 8, cur++);
SETPAIR(hue_list[(i + 1) % 6], hue_list[i] + 8, cur++);
SETPAIR(hue_list[i] + 8, hue_list[(i + 1) % 6], cur++);
SETPAIR(hue_list[(i + 1) % 6] + 8, hue_list[i], cur++);
}
/* black on light gray, black on white, white on dark gray, dark gray
* on white, white on blue, light gray on blue (chosen arbitrarily) */
SETPAIR(CACA_BLACK, CACA_LIGHTGRAY, cur++);
SETPAIR(CACA_BLACK, CACA_WHITE, cur++);
SETPAIR(CACA_WHITE, CACA_DARKGRAY, cur++);
SETPAIR(CACA_DARKGRAY, CACA_WHITE, cur++);
SETPAIR(CACA_WHITE, CACA_BLUE, cur++);
SETPAIR(CACA_LIGHTGRAY, CACA_BLUE, cur++);
}
static void emulated_colors(void)
{
int i;
/* light gray on dark colour: emulate with light colour on dark colour
* white on dark colour: emulate with light gray on light colour
* black on light colour: emulate with dark gray on dark colour
* dark gray on light colour: emulate with dark colour on light colour
* light colour on dark gray: emulate with dark colour on dark gray
* dark colour on light gray: emulate with light colour on light gray
* dark colour on white: emulate with light colour on white */
for(i = 1; i < 7; i++)
{
if(i != CACA_BLUE)
{
SETPAIR(CACA_LIGHTGRAY, i, 128 +
slang_assoc[i + 8 + 16 * i]);
SETPAIR(CACA_WHITE, i, 128 +
slang_assoc[CACA_LIGHTGRAY + 16 * (i + 8)]);
}
SETPAIR(CACA_BLACK, i + 8,
128 + slang_assoc[CACA_DARKGRAY + 16 * i]);
SETPAIR(CACA_DARKGRAY, i + 8,
128 + slang_assoc[i + 16 * (i + 8)]);
SETPAIR(i + 8, CACA_DARKGRAY,
128 + slang_assoc[i + 16 * CACA_DARKGRAY]);
SETPAIR(i, CACA_LIGHTGRAY,
128 + slang_assoc[i + 8 + 16 * CACA_LIGHTGRAY]);
SETPAIR(i, CACA_WHITE,
128 + slang_assoc[i + 8 + 16 * CACA_WHITE]);
}
/* 120 degree hue pairs can be emulated as well; for instance blue on
* red can be emulated using magenta on red, and blue on green using
* cyan on green */
for(i = 0; i < 6; i++)
{
SETPAIR(hue_list[(i + 2) % 6], hue_list[i],
128 + slang_assoc[hue_list[(i + 1) % 6] + 16 * hue_list[i]]);
SETPAIR(hue_list[(i + 2) % 6] + 8, hue_list[i] + 8,
128 + slang_assoc[hue_list[(i + 1) % 6] + 16 * hue_list[i] + 136]);
SETPAIR(hue_list[(i + 2) % 6] + 8, hue_list[i],
128 + slang_assoc[hue_list[(i + 1) % 6] + 16 * hue_list[i] + 8]);
SETPAIR(hue_list[(i + 2) % 6], hue_list[i] + 8,
128 + slang_assoc[hue_list[(i + 1) % 6] + 16 * hue_list[i] + 128]);
SETPAIR(hue_list[(i + 4) % 6], hue_list[i],
128 + slang_assoc[hue_list[(i + 5) % 6] + 16 * hue_list[i]]);
SETPAIR(hue_list[(i + 4) % 6] + 8, hue_list[i] + 8,
128 + slang_assoc[hue_list[(i + 5) % 6] + 16 * hue_list[i] + 136]);
SETPAIR(hue_list[(i + 4) % 6] + 8, hue_list[i],
128 + slang_assoc[hue_list[(i + 5) % 6] + 16 * hue_list[i] + 8]);
SETPAIR(hue_list[(i + 4) % 6], hue_list[i] + 8,
128 + slang_assoc[hue_list[(i + 5) % 6] + 16 * hue_list[i] + 128]);
}
/* dark opposite on dark: emulate with dark opposite on black
* light opposite on dark: emulate with light opposite on black
* dark opposite on light: emulate with black on dark
* light opposite on light: emulate with white on light */
for(i = 0; i < 6; i++)
{
SETPAIR(hue_list[i], hue_list[(i + 3) % 6],
128 + slang_assoc[hue_list[i] + 16 * CACA_BLACK]);
SETPAIR(hue_list[i] + 8, hue_list[(i + 3) % 6],
128 + slang_assoc[hue_list[i] + 8 + 16 * CACA_BLACK]);
SETPAIR(hue_list[(i + 3) % 6], hue_list[i] + 8,
128 + slang_assoc[CACA_BLACK + 16 * hue_list[i]]);
SETPAIR(hue_list[(i + 3) % 6] + 8, hue_list[i] + 8,
128 + slang_assoc[CACA_WHITE + 16 * (hue_list[i] + 8)]);
}
}
static void unused_colors(void)
{
int i, j;
for(i = 0, j = 0; i < 16 * 16; i++)
{
if(palette[i] == -1)
{
SETPAIR(j, j, i);
j++;
}
}
}