X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=libs%2Fcanvas%2Fcolors.cc;h=7a108e7f85a36bd4aad3380478df053f9a0228f3;hb=aa77c2eb581a1952c48706cb0b74af1d74f27334;hp=a3a7565fc85773b7cf42b9828f53b6dd81534ec5;hpb=fdcb7923582e43f69419023db7985823b2ac1402;p=ardour.git diff --git a/libs/canvas/colors.cc b/libs/canvas/colors.cc index a3a7565fc8..7a108e7f85 100644 --- a/libs/canvas/colors.cc +++ b/libs/canvas/colors.cc @@ -17,10 +17,17 @@ */ #include +#include #include #include +#include + +#include "pbd/convert.h" +#include "pbd/failed_constructor.h" +#include "pbd/locale_guard.h" #include "canvas/colors.h" +#include "canvas/colorspace.h" using namespace std; using namespace ArdourCanvas; @@ -28,16 +35,29 @@ using namespace ArdourCanvas; using std::max; using std::min; +ArdourCanvas::Color +change_alpha (Color c, double a) +{ + return ((c & ~0xff) | (lrintf (a*255.0) & 0xff)); +} + void ArdourCanvas::color_to_hsv (Color color, double& h, double& s, double& v) { - double r, g, b, a; + double a; + color_to_hsva (color, h, s, v, a); +} + +void +ArdourCanvas::color_to_hsva (Color color, double& h, double& s, double& v, double& a) +{ + double r, g, b; double cmax; double cmin; double delta; - + color_to_rgba (color, r, g, b, a); - + if (r > g) { cmax = max (r, b); } else { @@ -56,11 +76,12 @@ ArdourCanvas::color_to_hsv (Color color, double& h, double& s, double& v) if (cmax == 0) { // r = g = b == 0 ... v is undefined, s = 0 - s = 0.0; - h = -1.0; + s = 0.0; + h = 0.0; + return; } - if (delta != 0.0) { + if (delta != 0.0) { if (cmax == r) { h = fmod ((g - b)/delta, 6.0); } else if (cmax == g) { @@ -68,8 +89,15 @@ ArdourCanvas::color_to_hsv (Color color, double& h, double& s, double& v) } else { h = ((r - g)/delta) + 4; } - + h *= 60.0; + + if (h < 0.0) { + /* negative values are legal but confusing, because + they alias positive values. + */ + h = 360 + h; + } } if (delta == 0 || cmax == 0) { @@ -80,23 +108,16 @@ ArdourCanvas::color_to_hsv (Color color, double& h, double& s, double& v) } ArdourCanvas::Color -ArdourCanvas::hsv_to_color (const HSV& hsv, double a) -{ - return hsv_to_color (hsv.h, hsv.s, hsv.v, a); -} - -ArdourCanvas::Color -ArdourCanvas::hsv_to_color (double h, double s, double v, double a) +ArdourCanvas::hsva_to_color (double h, double s, double v, double a) { s = min (1.0, max (0.0, s)); v = min (1.0, max (0.0, v)); if (s == 0) { - // achromatic (grey) return rgba_to_color (v, v, v, a); } - h = min (360.0, max (0.0, h)); + h = fmod (h + 360.0, 360.0); double c = v * s; double x = c * (1.0 - fabs(fmod(h / 60.0, 2) - 1.0)); @@ -114,7 +135,7 @@ ArdourCanvas::hsv_to_color (double h, double s, double v, double a) return rgba_to_color (x + m, m, c + m, a); } else if (h >= 300.0 && h < 360.0) { return rgba_to_color (c + m, m, x + m, a); - } + } return rgba_to_color (m, m, m, a); } @@ -151,8 +172,8 @@ ArdourCanvas::rgba_to_color (double r, double g, double b, double a) } // Inverse of sRGB "gamma" function. -static inline double -inv_gam_sRGB (double c) +static inline double +inv_gam_sRGB (double c) { if (c <= 0.04045) { return c/12.92; @@ -162,8 +183,8 @@ inv_gam_sRGB (double c) } // sRGB "gamma" function -static inline int -gam_sRGB(double v) +static inline int +gam_sRGB(double v) { if (v <= 0.0031308) { v *= 12.92; @@ -173,7 +194,7 @@ gam_sRGB(double v) return int (v*255+.5); } -static double +static double luminance (uint32_t c) { // sRGB luminance(Y) values @@ -184,44 +205,86 @@ luminance (uint32_t c) double r, g, b, a; ArdourCanvas::color_to_rgba (c, r, g, b, a); - + return (gam_sRGB (rY*inv_gam_sRGB(r) + gY*inv_gam_sRGB(g) + bY*inv_gam_sRGB(b))) / 255.0; -} +} uint32_t ArdourCanvas::contrasting_text_color (uint32_t c) { - static const uint32_t white = ArdourCanvas::rgba_to_color (1.0, 1.0, 1.0, 1.0); + /* use a slightly off-white... XXX should really look this up */ + + static const uint32_t white = ArdourCanvas::rgba_to_color (0.98, 0.98, 0.98, 1.0); static const uint32_t black = ArdourCanvas::rgba_to_color (0.0, 0.0, 0.0, 1.0); return (luminance (c) < 0.50) ? white : black; } + + HSV::HSV () - : h (1.0) + : h (0.0) , s (1.0) , v (1.0) + , a (1.0) { } -HSV::HSV (double hh, double ss, double vv) +HSV::HSV (double hh, double ss, double vv, double aa) : h (hh) , s (ss) , v (vv) + , a (aa) { + if (h < 0.0) { + /* normalize negative hue values into positive range */ + h = 360.0 + h; + } } HSV::HSV (Color c) { - color_to_hsv (c, h, s, v); + color_to_hsva (c, h, s, v, a); +} + +HSV::HSV (const std::string& str) +{ + stringstream ss (str); + ss >> h; + ss >> s; + ss >> v; + ss >> a; +} + +string +HSV::to_string () const +{ + PBD::LocaleGuard lg; + stringstream ss; + ss << h << ' '; + ss << s << ' '; + ss << v << ' '; + ss << a; + return ss.str(); +} + +bool +HSV::is_gray () const +{ + return s == 0; } void HSV::clamp () { - s = min (s, 1.0); - v = min (v, 1.0); - h = min (255.0, h); + h = fmod (h, 360.0); + if (h < 0.0) { + /* normalize negative hue values into positive range */ + h = 360.0 + h; + } + s = min (1.0, s); + v = min (1.0, v); + a = min (1.0, a); } HSV @@ -231,7 +294,8 @@ HSV::operator+ (const HSV& operand) const hsv.h = h + operand.h; hsv.s = s + operand.s; hsv.v = v + operand.v; - hsv.clamp(); + hsv.a = a + operand.a; + hsv.clamp (); return hsv; } @@ -241,32 +305,49 @@ HSV::operator- (const HSV& operand) const HSV hsv; hsv.h = h - operand.h; hsv.s = s - operand.s; - hsv.v = v - operand.v; - hsv.clamp(); + hsv.v = s - operand.v; + hsv.a = a - operand.a; + hsv.clamp (); return hsv; } -HSV -HSV::operator* (double d) const +HSV& +HSV::operator=(Color c) { - HSV hsv; - hsv.h = h * d; - hsv.s = s * d; - hsv.v = v * d; - hsv.clamp(); - return hsv; + color_to_hsva (c, h, s, v, a); + clamp (); + return *this; +} + +HSV& +HSV::operator=(const std::string& str) +{ + uint32_t c; + c = strtol (str.c_str(), 0, 16); + color_to_hsva (c, h, s, v, a); + clamp (); + return *this; +} + +bool +HSV::operator== (const HSV& other) +{ + return h == other.h && + s == other.s && + v == other.v && + a == other.a; } HSV HSV::shade (double factor) const { HSV hsv (*this); - + /* algorithm derived from a google palette website and analysis of their color palettes. - basic rule: to make a color darker, increase its saturation - until it reaches 88%, but then additionally reduce value/lightness + basic rule: to make a color darker, increase its saturation + until it reaches 88%, but then additionally reduce value/lightness by a larger amount. invert rule to make a color lighter. @@ -274,16 +355,14 @@ HSV::shade (double factor) const if (factor > 1.0) { if (s < 88) { - hsv.v *= 1.0/(factor/10.0); - } else { - hsv.s *= factor; + hsv.v += (hsv.v * (factor * 10.0)); } + hsv.s *= factor; } else { if (s < 88) { - hsv.v *= 1.0/factor; - } else { - hsv.s *= factor; + hsv.v -= (hsv.v * (factor * 10.0)); } + hsv.s *= factor; } hsv.clamp(); @@ -291,6 +370,18 @@ HSV::shade (double factor) const return hsv; } +HSV +HSV::outline () const +{ + if (luminance (color()) < 0.50) { + /* light color, darker outline: black with 15% opacity */ + return HSV (0.0, 0.0, 0.0, 0.15); + } else { + /* dark color, lighter outline: white with 15% opacity */ + return HSV (0.0, 0.0, 1.0, 0.15); + } +} + HSV HSV::mix (const HSV& other, double amount) const { @@ -305,77 +396,273 @@ HSV::mix (const HSV& other, double amount) const return hsv; } -void -HSV::print (std::ostream& o) const +HSV +HSV::delta (const HSV& other) const { - if (!is_gray()) { - o << "hsv " << h << '|' << s << '|' << v; + HSV d; + + if (is_gray() && other.is_gray()) { + d.h = 0.0; + d.s = 0.0; + d.v = v - other.v; + } else { + d.h = h - other.h; + d.s = s - other.s; + d.v = v - other.v; + } + d.a = a - other.a; + /* do not clamp - we are returning a delta */ + return d; +} + +double +HSV::distance (const HSV& other) const +{ + if (is_gray() && other.is_gray()) { + /* human color perception of achromatics generates about 450 + distinct colors. By contrast, CIE94 could give a maximal + perceptual distance of sqrt ((360^2) + 1 + 1) = 360. The 450 + are not evenly spread (Webers Law), so lets use 360 as an + approximation of the number of distinct achromatics. + + So, scale up the achromatic difference to give about + a maximal distance between v = 1.0 and v = 0.0 of 360. + + A difference of about 0.0055 will generate a return value of + 2, which is roughly the limit of human perceptual + discrimination for chromatics. + */ + return fabs (360.0 * (v - other.v)); + } + + if (is_gray() != other.is_gray()) { + /* no comparison possible */ + return DBL_MAX; + } + + /* Use CIE94 definition for now */ + + double sL, sA, sB; + double oL, oA, oB; + double r, g, b, alpha; // Careful, "a" is a field of this + Color c; + + c = hsva_to_color (h, s, v, a); + color_to_rgba (c, r, g, b, alpha); + Rgb2Lab (&sL, &sA, &sB, r, g, b); + + c = hsva_to_color (other.h, other.s, other.v, other.a); + color_to_rgba (c, r, g, b, alpha); + Rgb2Lab (&oL, &oA, &oB, r, g, b); + + // Weighting factors depending on the application (1 = default) + + const double whtL = 1.0; + const double whtC = 1.0; + const double whtH = 1.0; + + const double xC1 = sqrt ((sA * sA) + (sB * oB)); + const double xC2 = sqrt ((oA * oA) + (oB * oB)); + double xDL = oL - sL; + double xDC = xC2 - xC1; + const double xDE = sqrt (((sL - oL) * (sL - oL)) + + ((sA - oA) * (sA - oA)) + + ((sB - oB) * (sB - oB))); + + double xDH; + + if (sqrt (xDE) > (sqrt (abs (xDL)) + sqrt (abs (xDC)))) { + xDH = sqrt ((xDE * xDE) - (xDL * xDL) - (xDC * xDC)); } else { - o << "hsv gray"; + xDH = 0; } + + const double xSC = 1 + (0.045 * xC1); + const double xSH = 1 + (0.015 * xC1); + + xDL /= whtL; + xDC /= whtC * xSC; + xDH /= whtH * xSH; + + return sqrt ((xDL * xDL) + (xDC * xDC) + (xDH * xDH)); } -HSVA::HSVA () - : a (1.0) +HSV +HSV::opposite () const { + HSV hsv (*this); + hsv.h = fmod (h + 180.0, 360.0); + return hsv; } -HSVA::HSVA (double hh, double ss, double vv, double aa) - : HSV (hh, ss, vv) - , a (aa) +HSV +HSV::bw_text () const { + return HSV (contrasting_text_color (color())); } -HSVA::HSVA (Color c) +HSV +HSV::text () const +{ + return opposite (); +} + +HSV +HSV::selected () const { - color_to_hsv (c, h, s, v); - a = c & 0xff; + /* XXX hack */ + return HSV (Color (0xff0000)); } + void -HSVA::clamp () +HSV::print (std::ostream& o) const { - HSV::clamp (); - a = min (1.0, a); + if (!is_gray()) { + o << '(' << h << ',' << s << ',' << v << ',' << a << ')'; + } else { + o << "gray(" << v << ')'; + } } -HSVA -HSVA::operator+ (const HSVA& operand) const + +std::ostream& operator<<(std::ostream& o, const ArdourCanvas::HSV& hsv) { hsv.print (o); return o; } + +HSV +HSV::mod (SVAModifier const & svam) { - HSVA hsv; - hsv.h = h + operand.h; - hsv.s = s + operand.s; - hsv.v = v + operand.v; - hsv.a = a + operand.a; - return hsv; + return svam (*this); } -HSVA -HSVA::operator- (const HSVA& operand) const +SVAModifier::SVAModifier (string const &str) + : type (Add) + , _s (0) + , _v (0) + , _a (0) { - HSVA hsv; - hsv.h = h - operand.h; - hsv.s = s - operand.s; - hsv.a = a - operand.a; - return hsv; + from_string (str); } void -HSVA::print (std::ostream& o) const +SVAModifier::from_string (string const & str) { - if (!is_gray()) { - o << "hsva " << h << '|' << s << '|' << v << '|' << a; - } else { - o << "hsva gray"; + char op; + stringstream ss (str); + string mod; + + ss >> op; + + switch (op) { + case '*': + type = Multiply; + /* no-op values for multiply */ + _s = 1.0; + _v = 1.0; + _a = 1.0; + break; + case '+': + type = Add; + /* no-op values for add */ + _s = 0.0; + _v = 0.0; + _a = 0.0; + break; + case '=': + type = Assign; + /* this will avoid assignment in operator() (see below) */ + _s = -1.0; + _v = -1.0; + _a = -1.0; + break; + default: + throw failed_constructor (); + } + + string::size_type pos; + + while (ss) { + ss >> mod; + if ((pos = mod.find ("alpha:")) != string::npos) { + _a = PBD::atof (mod.substr (pos+6)); + } else if ((pos = mod.find ("saturate:")) != string::npos) { + _s = PBD::atof (mod.substr (pos+9)); + } else if ((pos = mod.find ("darkness:")) != string::npos) { + _v = PBD::atof (mod.substr (pos+9)); + } else { + throw failed_constructor (); + } } } +string +SVAModifier::to_string () const +{ + PBD::LocaleGuard lg; + stringstream ss; + + switch (type) { + case Add: + ss << '+'; + break; + case Multiply: + ss << '*'; + break; + case Assign: + ss << '='; + break; + } -ArdourCanvas::Color -ArdourCanvas::hsva_to_color (const HSVA& hsva) + if (_s >= 0.0) { + ss << " saturate:" << _s; + } + + if (_v >= 0.0) { + ss << " darker:" << _v; + } + + if (_a >= 0.0) { + ss << " alpha:" << _a; + } + + return ss.str(); +} + +HSV +SVAModifier::operator () (HSV& hsv) const { - return hsv_to_color (hsva.h, hsva.s, hsva.v, hsva.a); + HSV r (hsv); + + switch (type) { + case Add: + r.s += _s; + r.v += _v; + r.a += _a; + break; + case Multiply: + r.s *= _s; + r.v *= _v; + r.a *= _a; + break; + case Assign: + if (_s >= 0.0) { + r.s = _s; + } + if (_v >= 0.) { + r.v = _v; + } + if (_a >= 0.0) { + r.a = _a; + } + break; + } + + return r; } -std::ostream& operator<<(std::ostream& o, const ArdourCanvas::HSV& hsv) { hsv.print (o); return o; } -std::ostream& operator<<(std::ostream& o, const ArdourCanvas::HSVA& hsva) { hsva.print (o); return o; } +ArdourCanvas::Color +ArdourCanvas::color_at_alpha (ArdourCanvas::Color c, double a) +{ + double r, g, b, unused; + color_to_rgba (c, r, g, b, unused); + return rgba_to_color( r,g,b, a ); +}