/* * color.c - color functions * * Copyright © 2008-2009 Julien Danjou * Copyright © 2009 Uli Schlachter * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * */ #include "color.h" #include "globalconf.h" #include /* 0xFFFF / 0xFF == 0x101 (257) */ #define RGB_8TO16(i) (((i) & 0xff) * 0x101) #define RGB_16TO8(i) (((i) & 0xffff) / 0x101) /** Parse an hexadecimal color string to its component. * \param colstr The color string. * \param len The color string length. * \param red A pointer to the red color to fill. * \param green A pointer to the green color to fill. * \param blue A pointer to the blue color to fill. * \return True if everything alright. */ static bool color_parse(const char *colstr, ssize_t len, uint8_t *red, uint8_t *green, uint8_t *blue, uint8_t *alpha) { unsigned long colnum; char *p; *alpha = 0xff; colnum = strtoul(colstr + 1, &p, 16); if(len == 9 && (p - colstr) == 9) { *alpha = colnum & 0xff; colnum >>= 8; len -= 2; p -= 2; } if(len != 7 || colstr[0] != '#' || (p - colstr) != 7) { warn("awesome: error, invalid color '%s'", colstr); return false; } *red = (colnum >> 16) & 0xff; *green = (colnum >> 8) & 0xff; *blue = colnum & 0xff; return true; } /** Given a color component value in the range from 0x00 to 0xff and a mask that * specifies where the component is, move the component into place. For example, * component=0x12 and mask=0xff00 return 0x1200. Note that the mask can have a * different width, for example component=0x12 and mask=0xf00 return 0x100. * \param component The intensity of a color component. * \param mask A mask containing a consecutive number of bits set to 1 defining * where the component is. * \return A pixel value containing the giving component in the given component. */ static uint32_t apply_mask(uint8_t component, uint32_t mask) { unsigned int shift = 0; unsigned int width = 0; // Shift the mask right until the first set bit appears while (mask != 0 && (mask & 0x1) == 0) { shift++; mask >>= 1; } // Shift the mask right until we saw all set bits while ((mask & 0x1) == 1) { width++; mask >>= 1; } // The mask consists of [width] set bits followed by [shift] unset bits. // Modify the component accordingly. uint32_t result = component; // Scale the result up to the desired width if (width < 8) result >>= (8 - width); if (width > 8) result <<= (width - 8); return result << shift; } /** Send a request to initialize a X color. * \param color color_t struct to store color into. * \param colstr Color specification. * \param len The length of colstr (which still MUST be NULL terminated). * \param visual The visual for which the color is to be allocated. * \return request information. */ color_init_request_t color_init_unchecked(color_t *color, const char *colstr, ssize_t len, xcb_visualtype_t *visual) { color_init_request_t req; uint8_t red, green, blue, alpha; p_clear(&req, 1); if(!len) { req.has_error = true; return req; } req.color = color; /* The color is given in RGB value */ if(!color_parse(colstr, len, &red, &green, &blue, &alpha)) { warn("awesome: error, invalid color '%s'", colstr); req.has_error = true; return req; } req.colstr = colstr; req.has_error = false; if (visual->_class == XCB_VISUAL_CLASS_TRUE_COLOR || visual->_class == XCB_VISUAL_CLASS_DIRECT_COLOR) { uint32_t pixel = 0; pixel |= apply_mask(red, visual->red_mask); pixel |= apply_mask(blue, visual->blue_mask); pixel |= apply_mask(green, visual->green_mask); if (draw_visual_depth(globalconf.screen, visual->visual_id) == 32) { /* This is not actually in the X11 protocol, but we assume that this * is an ARGB visual and everything unset in some mask is alpha. */ pixel |= apply_mask(alpha, ~(visual->red_mask | visual->blue_mask | visual->green_mask)); } req.color->pixel = pixel; req.color->red = RGB_8TO16(red); req.color->green = RGB_8TO16(green); req.color->blue = RGB_8TO16(blue); req.color->alpha = RGB_8TO16(alpha); req.color->initialized = true; return req; } req.cookie_hexa = xcb_alloc_color_unchecked(globalconf.connection, globalconf.screen_cmap, RGB_8TO16(red), RGB_8TO16(green), RGB_8TO16(blue)); return req; } /** Initialize a X color. * \param req color_init request. * \return True if color allocation was successful. */ bool color_init_reply(color_init_request_t req) { if(req.has_error) return false; if(req.color->initialized) return true; xcb_alloc_color_reply_t *hexa_color; if((hexa_color = xcb_alloc_color_reply(globalconf.connection, req.cookie_hexa, NULL))) { req.color->pixel = hexa_color->pixel; req.color->red = hexa_color->red; req.color->green = hexa_color->green; req.color->blue = hexa_color->blue; req.color->alpha = 0xffff; req.color->initialized = true; p_delete(&hexa_color); return true; } warn("awesome: error, cannot allocate color '%s'", req.colstr); return false; } /** Push a color as a string onto the stack * \param L The Lua VM state. * \param c The color to push. * \return The number of elements pushed on stack. */ int luaA_pushcolor(lua_State *L, const color_t c) { uint8_t r = RGB_16TO8(c.red); uint8_t g = RGB_16TO8(c.green); uint8_t b = RGB_16TO8(c.blue); uint8_t a = RGB_16TO8(c.alpha); char s[1 + 4*2 + 1]; int len; if (a >= 0xff) len = snprintf(s, sizeof(s), "#%02x%02x%02x", r, g, b); else len = snprintf(s, sizeof(s), "#%02x%02x%02x%02x", r, g, b, a); lua_pushlstring(L, s, len); return 1; } // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80