Fix 2119764 "eyedropper doesn't work with straight blends" for circles.

[synfig.git] / synfig-core / trunk / src / modules / mod_gradient / curvegradient.cpp

diff --git a/synfig-core/trunk/src/modules/mod_gradient/curvegradient.cpp b/synfig-core/trunk/src/modules/mod_gradient/curvegradient.cpp
index d76d76d..7a489b7 100644 (file)
--- a/synfig-core/trunk/src/modules/mod_gradient/curvegradient.cpp
+++ b/synfig-core/trunk/src/modules/mod_gradient/curvegradient.cpp
@@ -1,11 +1,12 @@
 /* === S Y N F I G ========================================================= */
 /*!    \file curvegradient.cpp
-**     \brief Template Header
+**     \brief Implementation of the "Curve Gradient" layer
 **
 **     $Id$
 **
 **     \legal
 **     Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+**     Copyright (c) 2007 Chris Moore
 **
 **     This package is free software; you can redistribute it and/or
 **     modify it under the terms of the GNU General Public License as
@@ -53,8 +54,8 @@
 
 SYNFIG_LAYER_INIT(CurveGradient);
 SYNFIG_LAYER_SET_NAME(CurveGradient,"curve_gradient");
-SYNFIG_LAYER_SET_LOCAL_NAME(CurveGradient,_("Curve Gradient"));
-SYNFIG_LAYER_SET_CATEGORY(CurveGradient,_("Gradients"));
+SYNFIG_LAYER_SET_LOCAL_NAME(CurveGradient,N_("Curve Gradient"));
+SYNFIG_LAYER_SET_CATEGORY(CurveGradient,N_("Gradients"));
 SYNFIG_LAYER_SET_VERSION(CurveGradient,"0.0");
 SYNFIG_LAYER_SET_CVS_ID(CurveGradient,"$Id$");
 
@@ -72,7 +73,7 @@ inline float calculate_distance(const synfig::BLinePoint& a,const synfig::BLineP
 #endif
 }
 
-inline float calculate_distance(const std::vector<synfig::BLinePoint>& bline)
+inline float calculate_distance(const std::vector<synfig::BLinePoint>& bline, bool bline_loop)
 {
        std::vector<synfig::BLinePoint>::const_iterator iter,next,ret;
        std::vector<synfig::BLinePoint>::const_iterator end(bline.end());
@@ -83,10 +84,10 @@ inline float calculate_distance(const std::vector<synfig::BLinePoint>& bline)
 
        next=bline.begin();
 
-       //if(loop)
-       //      iter=--bline.end();
-       //else
-       iter=next++;
+       if(bline_loop)
+               iter=--bline.end();
+       else
+               iter=next++;
 
        for(;next!=end;iter=next++)
        {
@@ -197,12 +198,12 @@ find_closest(bool fast, const std::vector<synfig::BLinePoint>& bline,const Point
 inline void
 CurveGradient::sync()
 {
-       curve_length_=calculate_distance(bline);
+       curve_length_=calculate_distance(bline, bline_loop);
 }
 
 
 CurveGradient::CurveGradient():
-       offset(0,0),
+       origin(0,0),
        width(0.25),
        gradient(Color::black(), Color::white()),
        loop(false),
@@ -237,6 +238,7 @@ CurveGradient::color_func(const Point &point_, int quality, float supersample)co
        Real dist;
 
        float perp_dist;
+       bool edge_case = false;
 
        if(bline.size()==0)
                return Color::alpha();
@@ -249,7 +251,7 @@ CurveGradient::color_func(const Point &point_, int quality, float supersample)co
        else
        {
                float t;
-               Point point(point_-offset);
+               Point point(point_-origin);
 
                std::vector<synfig::BLinePoint>::const_iterator iter,next;
 
@@ -306,6 +308,31 @@ CurveGradient::color_func(const Point &point_, int quality, float supersample)co
                p1=curve(t);                     // the closest point on the curve
                tangent=deriv(t).norm(); // the unit tangent at that point
 
+               // if the point we're nearest to is at either end of the
+               // bline, our distance from the curve is the distance from the
+               // point on the curve.  we need to know which side of the
+               // curve we're on, so find the average of the two tangents at
+               // this point
+               if (t<0.00001 || t>0.99999)
+               {
+                       if (t<0.5)
+                       {
+                               if (iter->get_split_tangent_flag())
+                               {
+                                       tangent=(iter->get_tangent1().norm()+tangent).norm();
+                                       edge_case=true;
+                               }
+                       }
+                       else
+                       {
+                               if (next->get_split_tangent_flag())
+                               {
+                                       tangent=(next->get_tangent2().norm()+tangent).norm();
+                                       edge_case=true;
+                               }
+                       }
+               }
+
                if(perpendicular)
                {
                        tangent*=curve_length_;
@@ -335,17 +362,25 @@ CurveGradient::color_func(const Point &point_, int quality, float supersample)co
                        const Real mag(diff.inv_mag());
                        supersample=supersample*mag;
                        diff*=mag*mag;
-                       dist=((point_-offset)*diff-p1*diff);
+                       dist=((point_-origin)*diff-p1*diff);
                }
        }
        else                                            // not perpendicular
        {
-               diff=tangent.perp()*thickness*width;
+               if (edge_case)
+               {
+                       diff=(p1-(point_-origin));
+                       if(diff*tangent.perp()<0) diff=-diff;
+                       diff=diff.norm()*thickness*width;
+               }
+               else
+                       diff=tangent.perp()*thickness*width;
+
                p1-=diff*0.5;
                const Real mag(diff.inv_mag());
                supersample=supersample*mag;
                diff*=mag*mag;
-               dist=((point_-offset)*diff-p1*diff);
+               dist=((point_-origin)*diff-p1*diff);
        }
 
        if(loop)
@@ -405,7 +440,7 @@ CurveGradient::set_param(const String & param, const ValueBase &value)
 {
 
 
-       IMPORT(offset);
+       IMPORT(origin);
        IMPORT(perpendicular);
        IMPORT(fast);
 
@@ -422,13 +457,16 @@ CurveGradient::set_param(const String & param, const ValueBase &value)
        IMPORT(gradient);
        IMPORT(loop);
        IMPORT(zigzag);
+
+       IMPORT_AS(origin,"offset");
+
        return Layer_Composite::set_param(param,value);
 }
 
 ValueBase
 CurveGradient::get_param(const String & param)const
 {
-       EXPORT(offset);
+       EXPORT(origin);
        EXPORT(bline);
        EXPORT(gradient);
        EXPORT(loop);
@@ -448,8 +486,8 @@ CurveGradient::get_param_vocab()const
 {
        Layer::Vocab ret(Layer_Composite::get_param_vocab());
 
-       ret.push_back(ParamDesc("offset")
-                                 .set_local_name(_("Offset")));
+       ret.push_back(ParamDesc("origin")
+                                 .set_local_name(_("Origin")));
 
        ret.push_back(ParamDesc("width")
                                  .set_is_distance()
@@ -457,8 +495,8 @@ CurveGradient::get_param_vocab()const
 
        ret.push_back(ParamDesc("bline")
                                  .set_local_name(_("Vertices"))
-                                 .set_origin("offset")
-                                 .set_scalar("width")
+                                 .set_origin("origin")
+                                 .set_hint("width")
                                  .set_description(_("A list of BLine Points")));
 
        ret.push_back(ParamDesc("gradient")