remove use of boost::optional to define "undefined" Canvas::Rect, and use Rect::empty...

[ardour.git] / libs / canvas / colors.cc

diff --git a/libs/canvas/colors.cc b/libs/canvas/colors.cc
index a747124cb2fe2212552a7aeaec77296036b46749..0bd3f8b04961875622ffb3c847697c7188e43fe6 100644 (file)
--- a/libs/canvas/colors.cc
+++ b/libs/canvas/colors.cc
@@ -36,7 +36,7 @@ using std::max;
 using std::min;
 
 ArdourCanvas::Color
-change_alpha (Color c, double a)
+ArdourCanvas::change_alpha (Color c, double a)
 {
        return ((c & ~0xff) | (lrintf (a*255.0) & 0xff));
 }
@@ -55,9 +55,9 @@ ArdourCanvas::color_to_hsva (Color color, double& h, double& s, double& v, doubl
        double cmax;
        double cmin;
        double delta;
-       
+
        color_to_rgba (color, r, g, b, a);
-       
+
        if (r > g) {
                cmax = max (r, b);
        } else {
@@ -76,12 +76,12 @@ ArdourCanvas::color_to_hsva (Color color, double& h, double& s, double& v, doubl
 
        if (cmax == 0) {
                // r = g = b == 0 ... v is undefined, s = 0
-               s = 0.0;  
+               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) {
@@ -89,9 +89,9 @@ ArdourCanvas::color_to_hsva (Color color, double& h, double& s, double& v, doubl
                } else {
                        h = ((r - g)/delta) + 4;
                }
-               
+
                h *= 60.0;
-               
+
                if (h < 0.0) {
                        /* negative values are legal but confusing, because
                           they alias positive values.
@@ -135,7 +135,7 @@ ArdourCanvas::hsva_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);
 }
 
@@ -172,8 +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;
@@ -183,8 +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;
@@ -194,7 +194,7 @@ gam_sRGB(double v)
         return int (v*255+.5);
 }
 
-static double 
+static double
 luminance (uint32_t c)
 {
         // sRGB luminance(Y) values
@@ -205,9 +205,9 @@ 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)
@@ -226,7 +226,7 @@ HSV::HSV ()
        : h (0.0)
        , s (1.0)
        , v (1.0)
-       , a (1.0) 
+       , a (1.0)
 {
 }
 
@@ -234,7 +234,7 @@ HSV::HSV (double hh, double ss, double vv, double aa)
        : h (hh)
        , s (ss)
        , v (vv)
-       , a (aa) 
+       , a (aa)
 {
        if (h < 0.0) {
                /* normalize negative hue values into positive range */
@@ -259,6 +259,7 @@ HSV::HSV (const std::string& str)
 string
 HSV::to_string () const
 {
+       PBD::LocaleGuard lg;
        stringstream ss;
        ss << h << ' ';
        ss << s << ' ';
@@ -341,12 +342,12 @@ 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.
@@ -355,12 +356,12 @@ HSV::shade (double factor) const
        if (factor > 1.0) {
                if (s < 88) {
                        hsv.v += (hsv.v * (factor * 10.0));
-               } 
+               }
                hsv.s *= factor;
        } else {
                if (s < 88) {
                        hsv.v -= (hsv.v * (factor * 10.0));
-               } 
+               }
                hsv.s *= factor;
        }
 
@@ -420,13 +421,13 @@ 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 
+                  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.
@@ -444,7 +445,7 @@ HSV::distance (const HSV& other) const
        double sL, sA, sB;
        double oL, oA, oB;
        double r, g, b, alpha;  // Careful, "a" is a field of this
-       Color c; 
+       Color c;
 
        c = hsva_to_color (h, s, v, a);
        color_to_rgba (c, r, g, b, alpha);
@@ -458,7 +459,7 @@ HSV::distance (const HSV& other) const
 
        const double whtL = 1.0;
        const double whtC = 1.0;
-       const double whtH = 1.0;  
+       const double whtH = 1.0;
 
        const double xC1 = sqrt ((sA * sA) + (sB * oB));
        const double xC2 = sqrt ((oA * oA) + (oB * oB));
@@ -467,7 +468,7 @@ HSV::distance (const HSV& other) const
        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)))) {
@@ -482,7 +483,7 @@ HSV::distance (const HSV& other) const
        xDL /= whtL;
        xDC /= whtC * xSC;
        xDH /= whtH * xSH;
-       
+
        return sqrt ((xDL * xDL) + (xDC * xDC) + (xDH * xDH));
 }
 
@@ -596,7 +597,7 @@ SVAModifier::from_string (string const & str)
 string
 SVAModifier::to_string () const
 {
-       PBD::LocaleGuard lg ("C");
+       PBD::LocaleGuard lg;
        stringstream ss;
 
        switch (type) {
@@ -630,7 +631,7 @@ HSV
 SVAModifier::operator () (HSV& hsv)  const
 {
        HSV r (hsv);
-       
+
        switch (type) {
        case Add:
                r.s += _s;
@@ -658,3 +659,10 @@ SVAModifier::operator () (HSV& hsv)  const
        return r;
 }
 
+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 );
+}