/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- * ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is Oracle Corporation code. * * The Initial Developer of the Original Code is Oracle Corporation. * Portions created by the Initial Developer are Copyright (C) 2005 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Stuart Parmenter * * Alternatively, the contents of this file may be used under the terms of * either the GNU General Public License Version 2 or later (the "GPL"), or * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ #ifndef GFX_COLOR_H #define GFX_COLOR_H #ifdef MOZILLA_INTERNAL_API #include "nsPrintfCString.h" #endif #include "gfxTypes.h" /** * Fast approximate division by 255. It has the property that * for all 0 <= n <= 255*255, FAST_DIVIDE_BY_255(n) == n/255. * But it only uses two adds and two shifts instead of an * integer division (which is expensive on many processors). * * equivalent to ((v)/255) */ #define GFX_DIVIDE_BY_255(v) \ (((((unsigned)(v)) << 8) + ((unsigned)(v)) + 255) >> 16) /** * Fast premultiply macro * * equivalent to (((c)*(a))/255) */ #define GFX_PREMULTIPLY(c,a) GFX_DIVIDE_BY_255((c)*(a)) /** * Macro to pack the 4 8-bit channels (A,R,G,B) * into a 32-bit packed premultiplied pixel. * * The checks for 0 alpha or max alpha ensure that the * compiler selects the quicked calculation when alpha is constant. */ #define GFX_PACKED_PIXEL(a,r,g,b) \ ((a) == 0x00) ? 0x00000000 : \ ((a) == 0xFF) ? ((0xFF << 24) | ((r) << 16) | ((g) << 8) | (b)) \ : ((a) << 24) | \ (GFX_PREMULTIPLY(r,a) << 16) | \ (GFX_PREMULTIPLY(g,a) << 8) | \ (GFX_PREMULTIPLY(b,a)) /** * A color value, storing red, green, blue and alpha components. * This class does not use premultiplied alpha. * * XXX should this use doubles (instead of gfxFloat), for consistency with * cairo? */ struct THEBES_API gfxRGBA { gfxFloat r, g, b, a; enum PackedColorType { PACKED_ABGR, PACKED_ABGR_PREMULTIPLIED, PACKED_ARGB, PACKED_ARGB_PREMULTIPLIED, PACKED_XBGR, PACKED_XRGB }; gfxRGBA() { } gfxRGBA(const gfxRGBA& c) : r(c.r), g(c.g), b(c.b), a(c.a) {} /** * Intialize this color using explicit red, green, blue and alpha * values. */ gfxRGBA(gfxFloat _r, gfxFloat _g, gfxFloat _b, gfxFloat _a=1.0) : r(_r), g(_g), b(_b), a(_a) {} /** * Initialize this color from a packed 32-bit color. * The color value is interpreted based on colorType; * all values use the native platform endianness. * * @see gfxRGBA::Packed */ gfxRGBA(PRUint32 c, PackedColorType colorType = PACKED_ABGR) { if (colorType == PACKED_ABGR || colorType == PACKED_XBGR || colorType == PACKED_ABGR_PREMULTIPLIED) { r = ((c >> 0) & 0xff) / 255.0; g = ((c >> 8) & 0xff) / 255.0; b = ((c >> 16) & 0xff) / 255.0; a = ((c >> 24) & 0xff) / 255.0; } else if (colorType == PACKED_ARGB || colorType == PACKED_XRGB || colorType == PACKED_ARGB_PREMULTIPLIED) { b = ((c >> 0) & 0xff) / 255.0; g = ((c >> 8) & 0xff) / 255.0; r = ((c >> 16) & 0xff) / 255.0; a = ((c >> 24) & 0xff) / 255.0; } if (colorType == PACKED_ABGR_PREMULTIPLIED || colorType == PACKED_ARGB_PREMULTIPLIED) { if (a > 0.0) { r /= a; g /= a; b /= a; } } else if (colorType == PACKED_XBGR || colorType == PACKED_XRGB) { a = 1.0; } } /** * Initialize this color by parsing the given string. * XXX implement me! */ #if 0 gfxRGBA(const char* str) { a = 1.0; // if aString[0] is a #, parse it as hex // if aString[0] is a letter, parse it as a color name // if aString[0] is a number, parse it loosely as hex } #endif /** * Returns this color value as a packed 32-bit integer. This reconstructs * the int32 based on the given colorType, always in the native byte order. */ PRUint32 Packed(PackedColorType colorType = PACKED_ABGR) const { if (colorType == PACKED_ABGR || colorType == PACKED_XBGR) { return (((PRUint8)(a * 255.0) << 24) | ((PRUint8)(b * 255.0) << 16) | ((PRUint8)(g * 255.0) << 8) | ((PRUint8)(r * 255.0))); } else if (colorType == PACKED_ARGB || colorType == PACKED_XRGB) { return (((PRUint8)(a * 255.0) << 24) | ((PRUint8)(r * 255.0) << 16) | ((PRUint8)(g * 255.0) << 8) | ((PRUint8)(b * 255.0))); } else if (colorType == PACKED_ABGR_PREMULTIPLIED) { return (((PRUint8)(a * 255.0) << 24) | ((PRUint8)((b*a) * 255.0) << 16) | ((PRUint8)((g*a) * 255.0) << 8) | ((PRUint8)((r*a) * 255.0))); } else if (colorType == PACKED_ARGB_PREMULTIPLIED) { return (((PRUint8)(a * 255.0) << 24) | ((PRUint8)((r*a) * 255.0) << 16) | ((PRUint8)((g*a) * 255.0) << 8) | ((PRUint8)((b*a) * 255.0))); } else { return 0; } } #ifdef MOZILLA_INTERNAL_API /** * Convert this color to a hex value. For example, for rgb(255,0,0), * this will return FF0000. */ // XXX I'd really prefer to just have this return an nsACString // Does this function even make sense, since we're just ignoring the alpha value? void Hex(nsACString& result) const { nsPrintfCString hex(8, "%02x%02x%02x", PRUint8(r*255.0), PRUint8(g*255.0), PRUint8(b*255.0)); result.Assign(hex); } #endif }; #endif /* _GFX_COLOR_H */