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Diffstat (limited to 'src/color-rgba.h')
| -rw-r--r-- | src/color-rgba.h | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/src/color-rgba.h b/src/color-rgba.h new file mode 100644 index 000000000..24bc63b52 --- /dev/null +++ b/src/color-rgba.h @@ -0,0 +1,194 @@ +/** \file color-rgba.h + + A class to handle a RGBA color as one unit. + + Authors: + bulia byak <buliabyak@gmail.com> + + Copyright (C) 2004 Authors + + Released under GNU GPL, read the file 'COPYING' for more information +*/ +#ifndef SEEN_COLOR_RGBA_H +#define SEEN_COLOR_RGBA_H + +#include <glib/gmessages.h> +#include "libnr/nr-pixops.h" +#include "decimal-round.h" + +/** + \brief A class to contain a floating point RGBA color. +*/ +class ColorRGBA { +public: + /** + \brief A constructor to create the color from four floating + point values. + \param c0 Red + \param c1 Green + \param c2 Blue + \param c3 Alpha + + Load the values into the array of floats in this object. + */ + ColorRGBA(float c0, float c1, float c2, float c3) + { + _c[0] = c0; _c[1] = c1; + _c[2] = c2; _c[3] = c3; + } + + /** + \brief Create a quick ColorRGBA with all zeros + */ + ColorRGBA(void) + { + for (int i = 0; i < 4; i++) + _c[i] = 0.0; + } + + /** + \brief A constructor to create the color from an unsigned + int, as found everywhere when dealing with colors + \param intcolor rgba32 "unsigned int representation (0xRRGGBBAA) + + Separate the values and load them into the array of floats in this object. + TODO : maybe get rid of the NR_RGBA32_x C-style functions and replace + the calls with the bitshifting they do + */ + ColorRGBA(unsigned int intcolor) + { + _c[0] = NR_RGBA32_R(intcolor)/255.0; + _c[1] = NR_RGBA32_G(intcolor)/255.0; + _c[2] = NR_RGBA32_B(intcolor)/255.0; + _c[3] = NR_RGBA32_A(intcolor)/255.0; + + } + + /** + \brief Create a ColorRGBA using an array of floats + \param in_array The values to be placed into the object + + Go through each entry in the array and put it into \c _c. + */ + ColorRGBA(float in_array[4]) + { + for (int i = 0; i < 4; i++) + _c[i] = in_array[i]; + } + + /** + \brief Overwrite the values in this object with another \c ColorRGBA. + \param m Values to use for the array + \return This ColorRGBA object + + Copy all the values from \c m into \c this. + */ + ColorRGBA &operator=(ColorRGBA const &m) { + for (unsigned i = 0 ; i < 4 ; ++i) { + _c[i] = m._c[i]; + } + return *this; + } + + /** + \brief Grab a particular value from the ColorRGBA object + \param i Which value to grab + \return The requested value. + + First checks to make sure that the value is within the array, + and then return the value if it is. + */ + float operator[](unsigned int const i) const { + g_assert( unsigned(i) < 4 ); + return _c[i]; + } + + /** + \brief Check to ensure that two \c ColorRGBA's are equal + \param other The guy to check against + \return Whether or not they are equal + + Check each value to see if they are equal. If they all are, + return TRUE. + */ + bool operator== (const ColorRGBA other) const { + for (int i = 0; i < 4; i++) { + if (_c[i] != other[i]) + return FALSE; + } + return TRUE; + } + + /** + \brief Average two \c ColorRGBAs to create another one. + \param second The second RGBA, with this being the first + \param weight How much of each should be used. Zero is all + this while one is all the second. Default is + half and half. + + This function goes through all the points in the two objects and + merges them together based on the weighting. The current objects + value are multiplied by 1.0 - weight and the second object by weight. + This means that they should always be balanced by the parameter. + */ + ColorRGBA average (const ColorRGBA second, const float weight = 0.5) const { + float returnval[4]; + + for (int i = 0; i < 4; i++) { + returnval[i] = _c[i] * (1.0 - weight) + second[i] * weight; + } + + return ColorRGBA(returnval[0], returnval[1], returnval[2], returnval[3]); + } + + /** + \brief Create a ColorRGBA with the inverse color of the current ColorRGBA + + do 1 minus each color components (but not the alpha) and put it into \c _c. + */ + ColorRGBA getInverse() const { + return ColorRGBA( (1.0 - _c[0]), (1.0 - _c[1]), (1.0 - _c[2]), _c[3] ); + } + + /** + \brief Create a ColorRGBA with the inverse color of a given ColorRGBA + + do 1 minus each color components (but not the alpha) and put it into \c _c. + */ + ColorRGBA getInverse(const ColorRGBA ref) const { + return getInverse(ref); + } + + /** + \brief Give the rgba32 "unsigned int" representation of the color + + round each components*255 and combine them (RRGGBBAA). + WARNING : this reduces color precision (from float to 0->255 int per component) + but it should be expected since we request this kind of output + */ + unsigned int getIntValue() const { + + return (int(Inkscape::decimal_round(_c[0]*255, 0)) << 24) | + (int(Inkscape::decimal_round(_c[1]*255, 0)) << 16) | + (int(Inkscape::decimal_round(_c[2]*255, 0)) << 8) | + (int(Inkscape::decimal_round(_c[3]*255, 0))); + } + +private: + /** \brief Array of values that are stored. */ + float _c[4]; +}; + + +#endif /* !SEEN_COLOR_RGBA_H */ + +/* + Local Variables: + mode:c++ + c-file-style:"stroustrup" + c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) + indent-tabs-mode:nil + fill-column:99 + End: +*/ +// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 : |