/* * libcaca Colour ASCII-Art library * Copyright (c) 2002-2010 Sam Hocevar * All Rights Reserved * * This library 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://sam.zoy.org/wtfpl/COPYING for more details. */ /* * This file contains functions for attribute management and colourspace * conversions. */ #include "config.h" #include "caca.h" #include "caca_internals.h" static uint8_t nearest_ansi(uint16_t); /* RGB colours for the ANSI palette. There is no real standard, so we * use the same values as gnome-terminal. The 7th colour (brown) is a bit * special: 0xfa50 instead of 0xfaa0. */ static const uint16_t ansitab16[16] = { 0xf000, 0xf00a, 0xf0a0, 0xf0aa, 0xfa00, 0xfa0a, 0xfa50, 0xfaaa, 0xf555, 0xf55f, 0xf5f5, 0xf5ff, 0xff55, 0xff5f, 0xfff5, 0xffff, }; /* Same table, except on 14 bits (3-4-4-3) */ static const uint16_t ansitab14[16] = { 0x3800, 0x3805, 0x3850, 0x3855, 0x3d00, 0x3d05, 0x3d28, 0x3d55, 0x3aaa, 0x3aaf, 0x3afa, 0x3aff, 0x3faa, 0x3faf, 0x3ffa, 0x3fff, }; /** \brief Get the text attribute at the given coordinates. * * Get the internal \e libcaca attribute value of the character at the * given coordinates. The attribute value has 32 significant bits, * organised as follows from MSB to LSB: * - 3 bits for the background alpha * - 4 bits for the background red component * - 4 bits for the background green component * - 3 bits for the background blue component * - 3 bits for the foreground alpha * - 4 bits for the foreground red component * - 4 bits for the foreground green component * - 3 bits for the foreground blue component * - 4 bits for the bold, italics, underline and blink flags * * If the coordinates are outside the canvas boundaries, the current * attribute is returned. * * This function never fails. * * \param cv A handle to the libcaca canvas. * \param x X coordinate. * \param y Y coordinate. * \return The requested attribute. */ uint32_t caca_get_attr(caca_canvas_t const *cv, int x, int y) { if(x < 0 || x >= (int)cv->width || y < 0 || y >= (int)cv->height) return cv->curattr; return cv->attrs[x + y * cv->width]; } /** \brief Set the default character attribute. * * Set the default character attribute for drawing. Attributes define * foreground and background colour, transparency, bold, italics and * underline styles, as well as blink. String functions such as * caca_printf() and graphical primitive functions such as caca_draw_line() * will use this attribute. * * The value of \e attr is either: * - a 32-bit integer as returned by caca_get_attr(), in which case it * also contains colour information, * - a combination (bitwise OR) of style values (\e CACA_UNDERLINE, * \e CACA_BLINK, \e CACA_BOLD and \e CACA_ITALICS), in which case * setting the attribute does not modify the current colour information. * * To retrieve the current attribute value, use caca_get_attr(-1,-1). * * This function never fails. * * \param cv A handle to the libcaca canvas. * \param attr The requested attribute value. * \return This function always returns 0. */ int caca_set_attr(caca_canvas_t *cv, uint32_t attr) { if(attr < 0x00000010) attr = (cv->curattr & 0xfffffff0) | attr; cv->curattr = attr; return 0; } /** \brief Unset flags in the default character attribute. * * Unset flags in the default character attribute for drawing. Attributes * define foreground and background colour, transparency, bold, italics and * underline styles, as well as blink. String functions such as * caca_printf() and graphical primitive functions such as caca_draw_line() * will use this attribute. * * The value of \e attr is a combination (bitwise OR) of style values * (\e CACA_UNDERLINE, \e CACA_BLINK, \e CACA_BOLD and \e CACA_ITALICS). * Unsetting these attributes does not modify the current colour information. * * To retrieve the current attribute value, use caca_get_attr(-1,-1). * * This function never fails. * * \param cv A handle to the libcaca canvas. * \param attr The requested attribute values to unset. * \return This function always returns 0. */ int caca_unset_attr(caca_canvas_t *cv, uint32_t attr) { cv->curattr &= ~(attr & 0x0000000f); return 0; } /** \brief Toggle flags in the default character attribute. * * Toggle flags in the default character attribute for drawing. Attributes * define foreground and background colour, transparency, bold, italics and * underline styles, as well as blink. String functions such as * caca_printf() and graphical primitive functions such as caca_draw_line() * will use this attribute. * * The value of \e attr is a combination (bitwise OR) of style values * (\e CACA_UNDERLINE, \e CACA_BLINK, \e CACA_BOLD and \e CACA_ITALICS). * Toggling these attributes does not modify the current colour information. * * To retrieve the current attribute value, use caca_get_attr(-1,-1). * * This function never fails. * * \param cv A handle to the libcaca canvas. * \param attr The requested attribute values to toggle. * \return This function always returns 0. */ int caca_toggle_attr(caca_canvas_t *cv, uint32_t attr) { cv->curattr ^= attr & 0x0000000f; return 0; } /** \brief Set the character attribute at the given coordinates. * * Set the character attribute, without changing the character's value. If * the character at the given coordinates is a fullwidth character, both * cells' attributes are replaced. * * The value of \e attr is either: * - a 32-bit integer as returned by caca_get_attr(), in which case it * also contains colour information, * - a combination (bitwise OR) of style values (\e CACA_UNDERLINE, * \e CACA_BLINK, \e CACA_BOLD and \e CACA_ITALICS), in which case * setting the attribute does not modify the current colour information. * * This function never fails. * * \param cv A handle to the libcaca canvas. * \param x X coordinate. * \param y Y coordinate. * \param attr The requested attribute value. * \return This function always returns 0. */ int caca_put_attr(caca_canvas_t *cv, int x, int y, uint32_t attr) { uint32_t *curattr, *curchar; int xmin, xmax; if(x < 0 || x >= (int)cv->width || y < 0 || y >= (int)cv->height) return 0; xmin = xmax = x; curchar = cv->chars + x + y * cv->width; curattr = cv->attrs + x + y * cv->width; if(attr < 0x00000010) curattr[0] = (curattr[0] & 0xfffffff0) | attr; else curattr[0] = attr; if(x && curchar[0] == CACA_MAGIC_FULLWIDTH) { curattr[-1] = curattr[0]; xmin--; } else if(x + 1 < (int)cv->width && curchar[1] == CACA_MAGIC_FULLWIDTH) { curattr[1] = curattr[0]; xmax++; } if(!cv->dirty_disabled) caca_add_dirty_rect(cv, xmin, y, xmax - xmin + 1, 1); return 0; } /** \brief Set the default colour pair for text (ANSI version). * * Set the default ANSI colour pair for text drawing. String functions such * as caca_printf() and graphical primitive functions such as caca_draw_line() * will use these attributes. * * Color values are those defined in caca.h, such as CACA_RED * or CACA_TRANSPARENT. * * If an error occurs, -1 is returned and \b errno is set accordingly: * - \c EINVAL At least one of the colour values is invalid. * * \param cv A handle to the libcaca canvas. * \param fg The requested ANSI foreground colour. * \param bg The requested ANSI background colour. * \return 0 in case of success, -1 if an error occurred. */ int caca_set_color_ansi(caca_canvas_t *cv, uint8_t fg, uint8_t bg) { uint32_t attr; if(fg > 0x20 || bg > 0x20) { seterrno(EINVAL); return -1; } attr = ((uint32_t)(bg | 0x40) << 18) | ((uint32_t)(fg | 0x40) << 4); cv->curattr = (cv->curattr & 0x0000000f) | attr; return 0; } /** \brief Set the default colour pair for text (truecolor version). * * Set the default ARGB colour pair for text drawing. String functions such * as caca_printf() and graphical primitive functions such as caca_draw_line() * will use these attributes. * * Colors are 16-bit ARGB values, each component being coded on 4 bits. For * instance, 0xf088 is solid dark cyan (A=15 R=0 G=8 B=8), and 0x8fff is * white with 50% alpha (A=8 R=15 G=15 B=15). * * This function never fails. * * \param cv A handle to the libcaca canvas. * \param fg The requested ARGB foreground colour. * \param bg The requested ARGB background colour. * \return This function always returns 0. */ int caca_set_color_argb(caca_canvas_t *cv, uint16_t fg, uint16_t bg) { uint32_t attr; if(fg < 0x100) fg += 0x100; if(bg < 0x100) bg += 0x100; fg = ((fg >> 1) & 0x7ff) | ((fg >> 13) << 11); bg = ((bg >> 1) & 0x7ff) | ((bg >> 13) << 11); attr = ((uint32_t)bg << 18) | ((uint32_t)fg << 4); cv->curattr = (cv->curattr & 0x0000000f) | attr; return 0; } /** \brief Get DOS ANSI information from attribute. * * Get the ANSI colour pair for a given attribute. The returned value is * an 8-bit value whose higher 4 bits are the background colour and lower * 4 bits are the foreground colour. * * If the attribute has ARGB colours, the nearest colour is used. Special * attributes such as \e CACA_DEFAULT and \e CACA_TRANSPARENT are not * handled and are both replaced with \e CACA_LIGHTGRAY for the foreground * colour and \e CACA_BLACK for the background colour. * * This function never fails. If the attribute value is outside the expected * 32-bit range, higher order bits are simply ignored. * * \param attr The requested attribute value. * \return The corresponding DOS ANSI value. */ uint8_t caca_attr_to_ansi(uint32_t attr) { uint8_t fg = nearest_ansi((attr >> 4) & 0x3fff); uint8_t bg = nearest_ansi(attr >> 18); return (fg < 0x10 ? fg : CACA_LIGHTGRAY) | ((bg < 0x10 ? bg : CACA_BLACK) << 4); } /** \brief Get ANSI foreground information from attribute. * * Get the ANSI foreground colour value for a given attribute. The returned * value is either one of the \e CACA_RED, \e CACA_BLACK etc. predefined * colours, or the special value \e CACA_DEFAULT meaning the media's * default foreground value, or the special value \e CACA_TRANSPARENT. * * If the attribute has ARGB colours, the nearest colour is returned. * * This function never fails. If the attribute value is outside the expected * 32-bit range, higher order bits are simply ignored. * * \param attr The requested attribute value. * \return The corresponding ANSI foreground value. */ uint8_t caca_attr_to_ansi_fg(uint32_t attr) { return nearest_ansi(((uint16_t)attr >> 4) & 0x3fff); } /** \brief Get ANSI background information from attribute. * * Get the ANSI background colour value for a given attribute. The returned * value is either one of the \e CACA_RED, \e CACA_BLACK etc. predefined * colours, or the special value \e CACA_DEFAULT meaning the media's * default background value, or the special value \e CACA_TRANSPARENT. * * If the attribute has ARGB colours, the nearest colour is returned. * * This function never fails. If the attribute value is outside the expected * 32-bit range, higher order bits are simply ignored. * * \param attr The requested attribute value. * \return The corresponding ANSI background value. */ uint8_t caca_attr_to_ansi_bg(uint32_t attr) { return nearest_ansi(attr >> 18); } /** \brief Get 12-bit RGB foreground information from attribute. * * Get the 12-bit foreground colour value for a given attribute. The returned * value is a native-endian encoded integer with each red, green and blue * values encoded on 8 bits in the following order: * - 8-11 most significant bits: red * - 4-7 most significant bits: green * - least significant bits: blue * * This function never fails. If the attribute value is outside the expected * 32-bit range, higher order bits are simply ignored. * * \param attr The requested attribute value. * \return The corresponding 12-bit RGB foreground value. */ uint16_t caca_attr_to_rgb12_fg(uint32_t attr) { uint16_t fg = (attr >> 4) & 0x3fff; if(fg < (0x10 | 0x40)) return ansitab16[fg ^ 0x40] & 0x0fff; if(fg == (CACA_DEFAULT | 0x40)) return ansitab16[CACA_LIGHTGRAY] & 0x0fff; if(fg == (CACA_TRANSPARENT | 0x40)) return ansitab16[CACA_LIGHTGRAY] & 0x0fff; return (fg << 1) & 0x0fff; } /** \brief Get 12-bit RGB background information from attribute. * * Get the 12-bit background colour value for a given attribute. The returned * value is a native-endian encoded integer with each red, green and blue * values encoded on 8 bits in the following order: * - 8-11 most significant bits: red * - 4-7 most significant bits: green * - least significant bits: blue * * This function never fails. If the attribute value is outside the expected * 32-bit range, higher order bits are simply ignored. * * \param attr The requested attribute value. * \return The corresponding 12-bit RGB background value. */ uint16_t caca_attr_to_rgb12_bg(uint32_t attr) { uint16_t bg = attr >> 18; if(bg < (0x10 | 0x40)) return ansitab16[bg ^ 0x40] & 0x0fff; if(bg == (CACA_DEFAULT | 0x40)) return ansitab16[CACA_BLACK] & 0x0fff; if(bg == (CACA_TRANSPARENT | 0x40)) return ansitab16[CACA_BLACK] & 0x0fff; return (bg << 1) & 0x0fff; } /** \brief Get 64-bit ARGB information from attribute. * * Get the 64-bit colour and alpha values for a given attribute. The values * are written as 8-bit integers in the \e argb array in the following order: * - \e argb[0]: background alpha value * - \e argb[1]: background red value * - \e argb[2]: background green value * - \e argb[3]: background blue value * - \e argb[4]: foreground alpha value * - \e argb[5]: foreground red value * - \e argb[6]: foreground green value * - \e argb[7]: foreground blue value * * This function never fails. If the attribute value is outside the expected * 32-bit range, higher order bits are simply ignored. * * \param attr The requested attribute value. * \param argb An array of 8-bit integers. */ void caca_attr_to_argb64(uint32_t attr, uint8_t argb[8]) { uint16_t fg = (attr >> 4) & 0x3fff; uint16_t bg = attr >> 18; if(bg < (0x10 | 0x40)) bg = ansitab16[bg ^ 0x40]; else if(bg == (CACA_DEFAULT | 0x40)) bg = ansitab16[CACA_BLACK]; else if(bg == (CACA_TRANSPARENT | 0x40)) bg = 0x0fff; else bg = ((bg << 2) & 0xf000) | ((bg << 1) & 0x0fff); argb[0] = bg >> 12; argb[1] = (bg >> 8) & 0xf; argb[2] = (bg >> 4) & 0xf; argb[3] = bg & 0xf; if(fg < (0x10 | 0x40)) fg = ansitab16[fg ^ 0x40]; else if(fg == (CACA_DEFAULT | 0x40)) fg = ansitab16[CACA_LIGHTGRAY]; else if(fg == (CACA_TRANSPARENT | 0x40)) fg = 0x0fff; else fg = ((fg << 2) & 0xf000) | ((fg << 1) & 0x0fff); argb[4] = fg >> 12; argb[5] = (fg >> 8) & 0xf; argb[6] = (fg >> 4) & 0xf; argb[7] = fg & 0xf; } /* * XXX: the following functions are local */ static uint8_t nearest_ansi(uint16_t argb14) { unsigned int i, best, dist; if(argb14 < (0x10 | 0x40)) return argb14 ^ 0x40; if(argb14 == (CACA_DEFAULT | 0x40) || argb14 == (CACA_TRANSPARENT | 0x40)) return argb14 ^ 0x40; if(argb14 < 0x0fff) /* too transparent */ return CACA_TRANSPARENT; best = CACA_DEFAULT; dist = 0x3fff; for(i = 0; i < 16; i++) { unsigned int d = 0; int a, b; a = (ansitab14[i] >> 7) & 0xf; b = (argb14 >> 7) & 0xf; d += (a - b) * (a - b); a = (ansitab14[i] >> 3) & 0xf; b = (argb14 >> 3) & 0xf; d += (a - b) * (a - b); a = (ansitab14[i] << 1) & 0xf; b = (argb14 << 1) & 0xf; d += (a - b) * (a - b); if(d < dist) { dist = d; best = i; } } return best; } #define RGB12TO24(i) \ (((uint32_t)((i & 0xf00) >> 8) * 0x110000) \ | ((uint32_t)((i & 0x0f0) >> 4) * 0x001100) \ | ((uint32_t)(i & 0x00f) * 0x000011)) uint32_t _caca_attr_to_rgb24fg(uint32_t attr) { return RGB12TO24(caca_attr_to_rgb12_fg(attr)); } uint32_t _caca_attr_to_rgb24bg(uint32_t attr) { return RGB12TO24(caca_attr_to_rgb12_bg(attr)); } /* * XXX: The following functions are aliases. */ uint32_t cucul_get_attr(cucul_canvas_t const *, int, int) CACA_ALIAS(caca_get_attr); int cucul_set_attr(cucul_canvas_t *, uint32_t) CACA_ALIAS(caca_set_attr); int cucul_put_attr(cucul_canvas_t *, int, int, uint32_t) CACA_ALIAS(caca_put_attr); int cucul_set_color_ansi(cucul_canvas_t *, uint8_t, uint8_t) CACA_ALIAS(caca_set_color_ansi); int cucul_set_color_argb(cucul_canvas_t *, uint16_t, uint16_t) CACA_ALIAS(caca_set_color_argb); uint8_t cucul_attr_to_ansi(uint32_t) CACA_ALIAS(caca_attr_to_ansi); uint8_t cucul_attr_to_ansi_fg(uint32_t) CACA_ALIAS(caca_attr_to_ansi_fg); uint8_t cucul_attr_to_ansi_bg(uint32_t) CACA_ALIAS(caca_attr_to_ansi_bg); uint16_t cucul_attr_to_rgb12_fg(uint32_t) CACA_ALIAS(caca_attr_to_rgb12_fg); uint16_t cucul_attr_to_rgb12_bg(uint32_t) CACA_ALIAS(caca_attr_to_rgb12_bg); void cucul_attr_to_argb64(uint32_t, uint8_t[8]) CACA_ALIAS(caca_attr_to_argb64);