Partially fix 1568818: Define mathematical operators so that we can animate gradients.

git-svn-id: http://svn.voria.com/code@675 1f10aa63-cdf2-0310-b900-c93c546f37ac

diff --git a/synfig-core/trunk/src/synfig/gradient.cpp b/synfig-core/trunk/src/synfig/gradient.cpp
index 11b2295..2411006 100644 (file)
--- a/synfig-core/trunk/src/synfig/gradient.cpp
+++ b/synfig-core/trunk/src/synfig/gradient.cpp
@@ -140,6 +140,89 @@ supersample_helper(const synfig::Gradient::CPoint &color1, const synfig::Gradien
 //     assert(0);
 }
 
+Gradient &
+synfig::Gradient::operator+=(const Gradient &rhs)
+{
+       CPointList ret;
+       const_iterator iter1 = begin(), iter2 = rhs.begin(), left_same, right_same;
+       CPoint left, right;
+       if (iter1 != end()) left = *iter1;
+       if (iter2 != rhs.end()) right = *iter2;
+       if (iter1 != end() && iter2 != rhs.end())
+               while(true)
+               {
+                       if (left.pos < right.pos)
+                       {
+                               ret.push_back(CPoint(left.pos, left.color + rhs(left.pos)));
+                               if(++iter1 == end()) break;
+                               left=*iter1;
+                       }
+                       else if (left.pos > right.pos)
+                       {
+                               ret.push_back(CPoint(right.pos, right.color + (*this)(right.pos)));
+                               if(++iter2 == rhs.end()) break;
+                               right=*iter2;
+                       }
+                       else
+                       {
+                               for(left_same = iter1++; (*iter1).pos == left.pos; iter1++);
+                               for(right_same = iter2++; (*iter2).pos == right.pos; iter2++);
+                               if (iter1 == left_same+1 && iter2 == right_same+1)
+                                       ret.push_back(CPoint(left.pos, left.color + right.color));
+                               else
+                               {
+                                       ret.push_back(CPoint(left.pos, left.color + right.color));
+                                       ret.push_back(CPoint(left.pos, (*(iter1-1)).color + (*(iter2-1)).color));
+                               }
+                               if (iter1 != end()) left=*iter1;
+                               if (iter2 == rhs.end()) break;
+                               right = *iter2;
+                               if (iter1 == end()) break;
+                       }
+               }
+
+       if (iter1 != end())
+               while(true)
+               {
+                       ret.push_back(CPoint(left.pos, left.color + rhs(left.pos)));
+                       if(++iter1 == end()) break;
+                       left = *iter1;
+               }
+
+       if (iter2 != rhs.end())
+               while(true)
+               {
+                       ret.push_back(CPoint(right.pos, right.color + (*this)(right.pos)));
+                       if(++iter2 == rhs.end()) break;
+                       right = *iter2;
+               }
+
+       cpoints = ret;
+       return *this;
+}
+
+Gradient &
+synfig::Gradient::operator-=(const Gradient &rhs)
+{
+       return (*this)+=(rhs*-1);
+}
+
+Gradient &
+synfig::Gradient::operator*=(const float    &rhs)
+{
+       for (iterator iter = cpoints.begin(); iter!=cpoints.end(); iter++)
+               (*iter).color *= rhs;
+       return *this;
+}
+
+Gradient &
+synfig::Gradient::operator/=(const float    &rhs)
+{
+       for (iterator iter = cpoints.begin(); iter!=cpoints.end(); iter++)
+               (*iter).color /= rhs;
+       return *this;
+}
+
 Color
 synfig::Gradient::operator()(const Real &x,float supersample)const
 {