Added copyright lines for files I've edited this year.
[synfig.git] / synfig-core / trunk / src / synfig / loadcanvas.cpp
index 6bbefc0..200456e 100644 (file)
@@ -6,6 +6,7 @@
 **
 **     \legal
 **     Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+**     Copyright (c) 2007, 2008 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
@@ -87,6 +88,8 @@ test_class test_class_instance;
 
 /* === M A C R O S ========================================================= */
 
+#define VALUENODE_COMPATIBILITY_URL "http://synfig.org/Convert#Compatibility"
+
 inline bool is_whitespace(char x) { return ((x)=='\n' || (x)=='\t' || (x)==' '); }
 
 /* === P R O C E D U R E S ================================================= */
@@ -234,7 +237,7 @@ CanvasParser::parse_keyframe(xmlpp::Element *element,Canvas::Handle canvas)
 
 
 Real
-CanvasParser::parse_real(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_real(xmlpp::Element *element)
 {
        assert(element->get_name()=="real");
 
@@ -272,7 +275,7 @@ CanvasParser::parse_time(xmlpp::Element *element,Canvas::Handle canvas)
 }
 
 int
-CanvasParser::parse_integer(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_integer(xmlpp::Element *element)
 {
        assert(element->get_name()=="integer");
 
@@ -290,8 +293,17 @@ CanvasParser::parse_integer(xmlpp::Element *element,Canvas::Handle canvas)
        return atoi(val.c_str());
 }
 
+// see 'minor hack' at the end of parse_vector() below
+// making this 'static' to give it file local scope
+// stops it working (where working means working around
+// bug #1509627)
+Vector &canvas_parser_vector_id(Vector &vector)
+{
+       return vector;
+}
+
 Vector
-CanvasParser::parse_vector(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_vector(xmlpp::Element *element)
 {
        assert(element->get_name()=="vector");
 
@@ -332,11 +344,16 @@ CanvasParser::parse_vector(xmlpp::Element *element,Canvas::Handle canvas)
                else
                        error_unexpected_element(child,child->get_name());
        }
-       return vect;
+       // Minor hack - gcc 4.1.2 and earlier think that we're not using
+       // 'vect' and optimize it out at -O2 and higher.  This convinces
+       // them that we are really using it.
+       return canvas_parser_vector_id(vect);
+       // When the bug is fixed, we can just do this instead:
+       // return vect;
 }
 
 Color
-CanvasParser::parse_color(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_color(xmlpp::Element *element)
 {
        assert(element->get_name()=="color");
 
@@ -346,7 +363,7 @@ CanvasParser::parse_color(xmlpp::Element *element,Canvas::Handle canvas)
                return Color();
        }
 
-       Color color;
+       Color color(0);
 
        xmlpp::Element::NodeList list = element->get_children();
        for(xmlpp::Element::NodeList::iterator iter = list.begin(); iter != list.end(); ++iter)
@@ -402,7 +419,7 @@ CanvasParser::parse_color(xmlpp::Element *element,Canvas::Handle canvas)
 }
 
 synfig::String
-CanvasParser::parse_string(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_string(xmlpp::Element *element)
 {
        assert(element->get_name()=="string");
 
@@ -422,7 +439,7 @@ CanvasParser::parse_string(xmlpp::Element *element,Canvas::Handle canvas)
 }
 
 bool
-CanvasParser::parse_bool(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_bool(xmlpp::Element *element)
 {
        assert(element->get_name()=="bool");
 
@@ -448,7 +465,7 @@ CanvasParser::parse_bool(xmlpp::Element *element,Canvas::Handle canvas)
 }
 
 Gradient
-CanvasParser::parse_gradient(xmlpp::Element *node,Canvas::Handle canvas)
+CanvasParser::parse_gradient(xmlpp::Element *node)
 {
        assert(node->get_name()=="gradient");
        Gradient ret;
@@ -462,7 +479,7 @@ CanvasParser::parse_gradient(xmlpp::Element *node,Canvas::Handle canvas)
                else
                {
                        Gradient::CPoint cpoint;
-                       cpoint.color=parse_color(child,canvas);
+                       cpoint.color=parse_color(child);
 
                        if(!child->get_attribute("pos"))
                        {
@@ -505,7 +522,7 @@ CanvasParser::parse_list(xmlpp::Element *element,Canvas::Handle canvas)
 }
 
 Segment
-CanvasParser::parse_segment(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_segment(xmlpp::Element *element)
 {
        assert(element->get_name()=="segment");
 
@@ -545,7 +562,7 @@ CanvasParser::parse_segment(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       seg.p1=parse_vector(dynamic_cast<xmlpp::Element*>(*iter),canvas);
+                       seg.p1=parse_vector(dynamic_cast<xmlpp::Element*>(*iter));
                }
                else
                if(child->get_name()=="t1")
@@ -569,7 +586,7 @@ CanvasParser::parse_segment(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       seg.t1=parse_vector(dynamic_cast<xmlpp::Element*>(*iter),canvas);
+                       seg.t1=parse_vector(dynamic_cast<xmlpp::Element*>(*iter));
                }
                else
                if(child->get_name()=="p2")
@@ -593,7 +610,7 @@ CanvasParser::parse_segment(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       seg.p2=parse_vector(dynamic_cast<xmlpp::Element*>(*iter),canvas);
+                       seg.p2=parse_vector(dynamic_cast<xmlpp::Element*>(*iter));
                }
                else
                if(child->get_name()=="t2")
@@ -617,7 +634,7 @@ CanvasParser::parse_segment(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       seg.t2=parse_vector(dynamic_cast<xmlpp::Element*>(*iter),canvas);
+                       seg.t2=parse_vector(dynamic_cast<xmlpp::Element*>(*iter));
                }
                else
                        error_unexpected_element(child,child->get_name());
@@ -626,7 +643,7 @@ CanvasParser::parse_segment(xmlpp::Element *element,Canvas::Handle canvas)
 }
 
 BLinePoint
-CanvasParser::parse_bline_point(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_bline_point(xmlpp::Element *element)
 {
        assert(element->get_name()=="bline_point");
        if(element->get_children().empty())
@@ -667,7 +684,7 @@ CanvasParser::parse_bline_point(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       ret.set_vertex(parse_vector(dynamic_cast<xmlpp::Element*>(*iter),canvas));
+                       ret.set_vertex(parse_vector(dynamic_cast<xmlpp::Element*>(*iter)));
                }
                else
                // Tangent 1
@@ -692,7 +709,7 @@ CanvasParser::parse_bline_point(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       ret.set_tangent1(parse_vector(dynamic_cast<xmlpp::Element*>(*iter),canvas));
+                       ret.set_tangent1(parse_vector(dynamic_cast<xmlpp::Element*>(*iter)));
                }
                else
                // Tangent 2
@@ -717,7 +734,7 @@ CanvasParser::parse_bline_point(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       ret.set_tangent2(parse_vector(dynamic_cast<xmlpp::Element*>(*iter),canvas));
+                       ret.set_tangent2(parse_vector(dynamic_cast<xmlpp::Element*>(*iter)));
                        ret.set_split_tangent_flag(true);
                }
                else
@@ -743,7 +760,7 @@ CanvasParser::parse_bline_point(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       ret.set_width(parse_real(dynamic_cast<xmlpp::Element*>(*iter),canvas));
+                       ret.set_width(parse_real(dynamic_cast<xmlpp::Element*>(*iter)));
                }
                else
                // origin
@@ -768,7 +785,7 @@ CanvasParser::parse_bline_point(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       ret.set_origin(parse_real(dynamic_cast<xmlpp::Element*>(*iter),canvas));
+                       ret.set_origin(parse_real(dynamic_cast<xmlpp::Element*>(*iter)));
                }
                else
                        error_unexpected_element(child,child->get_name());
@@ -777,7 +794,7 @@ CanvasParser::parse_bline_point(xmlpp::Element *element,Canvas::Handle canvas)
 }
 
 Angle
-CanvasParser::parse_angle(xmlpp::Element *element,Canvas::Handle canvas)
+CanvasParser::parse_angle(xmlpp::Element *element)
 {
        assert(element->get_name()=="angle");
 
@@ -799,51 +816,48 @@ ValueBase
 CanvasParser::parse_value(xmlpp::Element *element,Canvas::Handle canvas)
 {
        if(element->get_name()=="real")
-               return parse_real(element,canvas);
+               return parse_real(element);
        else
        if(element->get_name()=="time")
                return parse_time(element,canvas);
        else
        if(element->get_name()=="integer")
-               return parse_integer(element,canvas);
+               return parse_integer(element);
        else
        if(element->get_name()=="string")
-               return parse_string(element,canvas);
+               return parse_string(element);
        else
        if(element->get_name()=="vector")
-       {
-               return parse_vector(element,canvas);
-       }
+               return parse_vector(element);
        else
        if(element->get_name()=="color")
-               return parse_color(element,canvas);
+               return parse_color(element);
        else
        if(element->get_name()=="segment")
-               return parse_segment(element,canvas);
+               return parse_segment(element);
        else
        if(element->get_name()=="list")
                return parse_list(element,canvas);
        else
        if(element->get_name()=="gradient")
-               return parse_gradient(element,canvas);
+               return parse_gradient(element);
        else
        if(element->get_name()=="bool")
-               return parse_bool(element,canvas);
+               return parse_bool(element);
        else
        //if(element->get_name()=="canvas")
        //      return parse_canvas(element,canvas,true);       // inline canvas
        //else
        if(element->get_name()=="angle" || element->get_name()=="degrees" || element->get_name()=="radians" || element->get_name()=="rotations")
-               return parse_angle(element,canvas);
+               return parse_angle(element);
        else
        if(element->get_name()=="bline_point")
-               return parse_bline_point(element,canvas);
+               return parse_bline_point(element);
        else
        if(element->get_name()=="canvas")
                return ValueBase(parse_canvas(element,canvas,true));
        else
        {
-               DEBUGPOINT();
                error_unexpected_element(element,element->get_name());
        }
 
@@ -876,7 +890,7 @@ CanvasParser::parse_animated(xmlpp::Element *element,Canvas::Handle canvas)
 
        if(!value_node)
        {
-               error(element,strprintf(_("Unable to create <animated> with type \"%s\""),ValueBase::type_name(type).c_str()));
+               error(element,strprintf(_("Unable to create <animated> with type \"%s\""),ValueBase::type_local_name(type).c_str()));
                return ValueNode_Animated::Handle();
        }
 
@@ -901,10 +915,22 @@ CanvasParser::parse_animated(xmlpp::Element *element,Canvas::Handle canvas)
 
 
                        ValueNode::Handle waypoint_value_node;
+                       xmlpp::Element::NodeList list = child->get_children();
 
                        if(child->get_attribute("use"))
                        {
-                               waypoint_value_node=canvas->surefind_value_node(child->get_attribute("use")->get_value());
+                               if(!list.empty())
+                                       warning(child,_("Found \"use\" attribute for <waypoint>, but it wasn't empty. Ignoring contents..."));
+
+                               // the waypoint might look like this, in which case we won't find "mycanvas" in the list of valuenodes, 'cos it's a canvas
+                               //
+                               //      <animated type="canvas">
+                               //        <waypoint time="0s" use="mycanvas"/>
+                               //      </animated>
+                               if (type==ValueBase::TYPE_CANVAS)
+                                       waypoint_value_node=ValueNode_Const::create(canvas->surefind_canvas(child->get_attribute("use")->get_value()));
+                               else
+                                       waypoint_value_node=canvas->surefind_value_node(child->get_attribute("use")->get_value());
                        }
                        else
                        {
@@ -914,7 +940,6 @@ CanvasParser::parse_animated(xmlpp::Element *element,Canvas::Handle canvas)
                                        continue;
                                }
 
-                               xmlpp::Element::NodeList list = child->get_children();
                                xmlpp::Element::NodeList::iterator iter;
 
                                // Search for the first non-text XML element
@@ -1027,415 +1052,177 @@ CanvasParser::parse_animated(xmlpp::Element *element,Canvas::Handle canvas)
                else
                        error_unexpected_element(child,child->get_name());
        }
-       value_node->changed();
-       return value_node;
-}
-
-// This function is a phase-out hack for the timed swap value node
-etl::handle<ValueNode_Animated>
-CanvasParser::parse_timedswap(xmlpp::Element *node,Canvas::Handle canvas)
-{
-       ValueNode_TimedSwap::Handle timed_swap(parse_linkable_value_node(node,canvas));
-
-       assert(timed_swap);
-
-       ValueNode_Animated::Handle animated(ValueNode_Animated::create(timed_swap->get_type()));
-
-       animated->set_root_canvas(canvas->get_root());
-
-       assert(animated);
-
-       Time swap_time, swap_length;
-       (*timed_swap->get_swap_time())(0).put(&swap_time);
-       (*timed_swap->get_swap_length())(0).put(&swap_length);
-
-       animated->new_waypoint(swap_time-swap_length,timed_swap->get_before());
-       animated->new_waypoint(swap_time,timed_swap->get_after());
-
-       return animated;
-}
-
-
-handle<ValueNode_Subtract>
-CanvasParser::parse_subtract(xmlpp::Element *element,Canvas::Handle canvas)
-{
-       assert(element->get_name()=="subtract");
-
-       handle<ValueNode_Subtract> value_node;
-       handle<ValueNode> lhs,rhs,scalar;
-
-       if(element->get_attribute("type"))
-       {
-               ValueBase::Type type=ValueBase::ident_type(element->get_attribute("type")->get_value());
-
-               if(!type)
-               {
-                       error(element,"Bad type in <subtract>");
-                       return ValueNode_Subtract::Handle();
-               }
-               value_node=ValueNode_Subtract::create(type);
-       }
-       else
-               value_node=ValueNode_Subtract::create();
-
-       if(!value_node)
-       {
-               error(element,strprintf(_("Unable to create <subtract>")));
-               return handle<ValueNode_Subtract>();
-       }
 
-       //if(element->get_attribute("scalar"))
-       //{
-       //      value_node->set_scalar(atof(element->get_attribute("scalar")->get_value().c_str()));
-       //}
+       // in canvas version 0.1, angles used to wrap, so to get from -179
+       // degrees to 180 degrees meant a 1 degree change
+       // in canvas version 0.2 they don't, so that's a 359 degree change
 
-       try
+       // when loading a version 0.1 canvas, modify constant angle
+       // waypoints to that they are within 180 degrees of the previous
+       // waypoint's value
+       if (type == ValueBase::TYPE_ANGLE) 
        {
-               if(element->get_attribute("scalar"))
-               {
-                       // This is for compatibility with older versions of the file format
-                       String value(element->get_attribute("scalar")->get_value());
-                       if((value[0]<='9' && value[0]>='0')      || value[0]=='-')
-                       {
-                               warning(element, _("Use of a real value where the ID should be is deprecated"));
-                               value_node->set_scalar(atof(value.c_str()));
-                       }
-                       else
-                               value_node->set_scalar(canvas->surefind_value_node(value));
-                       scalar=value_node->get_scalar();
-               }
-
-               if(element->get_attribute("lhs"))
+               if (canvas->get_version() == "0.1")
                {
-                       lhs=canvas->surefind_value_node(element->get_attribute("lhs")->get_value());
-                       value_node->set_lhs(lhs);
-               }
-
-               if(element->get_attribute("rhs"))
-               {
-                       rhs=canvas->surefind_value_node(element->get_attribute("rhs")->get_value());
-                       value_node->set_rhs(rhs);
-               }
-       }
-       catch (Exception::IDNotFound)
-       {
-               error(element,"attribute in <subtract> references unknown ID");
-       }
-       catch (Exception::FileNotFound)
-       {
-               error(element,"Unable to open external file referenced in ID");
-       }
-
-       xmlpp::Element::NodeList list = element->get_children();
-       for(xmlpp::Element::NodeList::iterator iter = list.begin(); iter != list.end(); ++iter)
-       {
-               xmlpp::Element *child(dynamic_cast<xmlpp::Element*>(*iter));
-               if(!child)
-                       continue;
-               else
-               if(child->get_name()=="lhs")
-               {
-                       if(lhs)
-                       {
-                               error(child,"LHS component of <subtract> already defined!");
-                               continue;
-                       }
-
-                       xmlpp::Element::NodeList list = child->get_children();
-                       xmlpp::Element::NodeList::iterator iter;
-
-                       // Search for the first non-text XML element
-                       for(iter = list.begin(); iter != list.end(); ++iter)
-                               if(dynamic_cast<xmlpp::Element*>(*iter)) break;
-
-                       if(iter==list.end())
-                       {
-                               error(child,_("<lhs> is missing its contents"));
-                               continue;
-                       }
-
-                       lhs=parse_value_node(dynamic_cast<xmlpp::Element*>(*iter),canvas);
-
-                       if(lhs)
-                               value_node->set_lhs(lhs);
-                       else
-                       {
-                               error((*iter),"Parse of LHS ValueNode failed");
-                       }
-
-                       // \todo do a search for more elements and warn if they are found
-               }
-               else
-               if(child->get_name()=="rhs")
-               {
-                       if(rhs)
-                       {
-                               error(child,"RHS component of <subtract> already defined!");
-                               continue;
-                       }
-
-                       xmlpp::Element::NodeList list = child->get_children();
-                       xmlpp::Element::NodeList::iterator iter;
-
-                       // Search for the first non-text XML element
-                       for(iter = list.begin(); iter != list.end(); ++iter)
-                               if(dynamic_cast<xmlpp::Element*>(*iter)) break;
-
-                       if(iter==list.end())
-                       {
-                               error(child,_("<rhs> is missing its contents"));
-                               continue;
-                       }
-
-                       rhs=parse_value_node(dynamic_cast<xmlpp::Element*>(*iter),canvas);
-
-                       if(rhs)
-                               value_node->set_rhs(rhs);
-                       else
-                       {
-                               error((*iter),"Parse of RHS ValueNode failed");
-                       }
-
-                       // \todo do a search for more elements and warn if they are found
-               }
-               else
-               if(child->get_name()=="scalar")
-               {
-                       if(scalar)
-                       {
-                               error(child,"scalar component of <subtract> already defined!");
-                               continue;
-                       }
-
-                       xmlpp::Element::NodeList list = child->get_children();
-                       xmlpp::Element::NodeList::iterator iter;
-
-                       // Search for the first non-text XML element
-                       for(iter = list.begin(); iter != list.end(); ++iter)
-                               if(dynamic_cast<xmlpp::Element*>(*iter)) break;
-
-                       if(iter==list.end())
-                       {
-                               error(child,_("<scalar> is missing its contents"));
-                               continue;
-                       }
-
-                       scalar=parse_value_node(dynamic_cast<xmlpp::Element*>(*iter),canvas);
-
-                       if(scalar)
-                               value_node->set_scalar(scalar);
-                       else
-                       {
-                               error((*iter),"Parse of scalar ValueNode failed");
+                       bool first = true;
+                       Real angle, prev = 0;
+                       WaypointList &wl = value_node->waypoint_list();
+                       for (WaypointList::iterator iter = wl.begin(); iter != wl.end(); iter++)
+                       {
+                               angle = Angle::deg(iter->get_value(iter->get_time()).get(Angle())).get();
+                               if (first)
+                                       first = false;
+                               else if (iter->get_value_node()->get_name() == "constant")
+                               {
+                                       if (angle - prev > 180)
+                                       {
+                                               while (angle - prev > 180) angle -= 360;
+                                               iter->set_value(Angle::deg(angle));
+                                       }
+                                       else if (prev - angle > 180)
+                                       {
+                                               while (prev - angle > 180) angle += 360;
+                                               iter->set_value(Angle::deg(angle));
+                                       }
+                               }
+                               prev = angle;
                        }
-
-                       // \todo do a search for more elements and warn if they are found
                }
-               else
-                       error_unexpected_element(child,child->get_name());
        }
 
-       if(!value_node->get_rhs() || !value_node->get_lhs() || !value_node->get_scalar())
-               error(element,"<subtract> is missing LHS, RHS, or SCALAR");
-
-       if(value_node->get_rhs() == value_node->get_lhs())
-               warning(element,"LHS is equal to RHS in <subtract>, so this value_node will always be zero!");
-
+       value_node->changed();
        return value_node;
 }
 
 etl::handle<LinkableValueNode>
 CanvasParser::parse_linkable_value_node(xmlpp::Element *element,Canvas::Handle canvas)
 {
-       handle<LinkableValueNode> value_node;
-       ValueBase::Type type;
-
        // Determine the type
-       if(element->get_attribute("type"))
+       if(!element->get_attribute("type"))
        {
-               type=ValueBase::ident_type(element->get_attribute("type")->get_value());
-
-               if(!type)
-               {
-                       error(element,"Bad type in ValueNode");
-                       return 0;
-               }
+               error(element, strprintf(_("Missing attribute \"type\" in <%s>"), element->get_name().c_str()));
+               return 0;
        }
-       else
+
+       ValueBase::Type type=ValueBase::ident_type(element->get_attribute("type")->get_value());
+
+       if(!type)
        {
-               error(element,"Missing type in ValueNode");
+               error(element, strprintf(_("Bad type in <%s>"), element->get_name().c_str()));
                return 0;
        }
 
-       value_node=LinkableValueNode::create(element->get_name(),type);
+       handle<LinkableValueNode> value_node=LinkableValueNode::create(element->get_name(),type);
+       handle<ValueNode> c[value_node->link_count()];
 
        if(!value_node)
        {
-               error(element,"Unknown ValueNode type "+element->get_name());
+               error(element, strprintf(_("Error creating ValueNode <%s> with type '%s'.  Refer to '%s'"),
+                                                                element->get_name().c_str(),
+                                                                ValueBase::type_local_name(type).c_str(),
+                                                                VALUENODE_COMPATIBILITY_URL));
                return 0;
        }
 
        if(value_node->get_type()!=type)
        {
-               error(element,"ValueNode did not accept type");
+               error(element, strprintf(_("<%s> did not accept type '%s'"),
+                                                                element->get_name().c_str(),
+                                                                ValueBase::type_local_name(type).c_str()));
                return 0;
        }
 
        value_node->set_root_canvas(canvas->get_root());
 
-       int i;
-       for(i=0;i<value_node->link_count();i++)
+       // handle exported valuenodes
        {
-               if(element->get_attribute(value_node->link_name(i)))
-               try {
-                       String id(element->get_attribute(value_node->link_name(i))->get_value());
-
-                       if(!value_node->set_link(i,
-                                       canvas->surefind_value_node(
-                                               id
-                                       )
-                               )
-                       ) error(element,strprintf(_("Unable to set link \"%s\" to ValueNode \"%s\" (link #%d in \"%s\")"),value_node->link_name(i).c_str(),id.c_str(),i,value_node->get_name().c_str()));
-               }
-               catch(Exception::IDNotFound)
-               {
-                       error(element,"Unable to resolve "+element->get_attribute(value_node->link_name(i))->get_value());
-               }
-               catch(Exception::FileNotFound)
+               int index;
+               String id, name;
+               xmlpp::Element::AttributeList attrib_list(element->get_attributes());
+               for(xmlpp::Element::AttributeList::iterator iter = attrib_list.begin(); iter != attrib_list.end(); iter++)
                {
-                       error(element,"Unable to open file referenced in "+element->get_attribute(value_node->link_name(i))->get_value());
-               }
-               catch(...)
-               {
-                       error(element,strprintf(_("Unknown Exception thrown when referencing ValueNode \"%s\""),
-                               element->get_attribute(value_node->link_name(i))->get_value().c_str()));
-                       throw;
-               }
-       }
+                       name = (*iter)->get_name();
+                       id = (*iter)->get_value();
 
+                       if (name == "guid" || name == "id" || name == "type")
+                               continue;
 
+                       try {
+                               index = value_node->get_link_index_from_name(name);
 
-       xmlpp::Element::NodeList list = element->get_children();
-       for(xmlpp::Element::NodeList::iterator iter = list.begin(); iter != list.end(); ++iter)
-       {
-               xmlpp::Element *child(dynamic_cast<xmlpp::Element*>(*iter));
-               try
-               {
-                       if(!child)
-                               continue;
-                       int index=value_node->get_link_index_from_name(child->get_name());
+                               if(c[index])
+                               {
+                                       error(element,strprintf(_("'%s' was already defined in <%s>"),
+                                                                                       name.c_str(),
+                                                                                       element->get_name().c_str()));
+                                       continue;
+                               }
 
-                       xmlpp::Element::NodeList list = child->get_children();
-                       xmlpp::Element::NodeList::iterator iter;
+                               c[index] = canvas->surefind_value_node(id);
 
-                       // Search for the first non-text XML element
-                       for(iter = list.begin(); iter != list.end(); ++iter)
-                               if(dynamic_cast<xmlpp::Element*>(*iter)) break;
+                               if (!c[index])
+                               {
+                                       error(element, strprintf(_("'%s' attribute in <%s> references unknown ID '%s'"),
+                                                                                        name.c_str(),
+                                                                                        element->get_name().c_str(),
+                                                                                        id.c_str()));
+                                       continue;
+                               }
 
-                       if(iter==list.end())
+                               if(!value_node->set_link(index, c[index]))
+                               {
+                                       error(element, strprintf(_("Unable to set link '\"%s\" to ValueNode \"%s\" (link #%d in \"%s\")"),
+                                                                                        value_node->link_name(index).c_str(),
+                                                                                        id.c_str(),
+                                                                                        index,
+                                                                                        element->get_name().c_str()));
+                                       continue;
+                               }
+
+                               // printf("  <%s> set link %d (%s) using exported value\n", element->get_name().c_str(), index, name.c_str());
+                       }
+                       catch (Exception::BadLinkName)
                        {
-                               error(child,_("element is missing its contents"));
-                               continue;
+                               warning(element, strprintf("Bad link name '%s'", name.c_str()));
                        }
-
-                       ValueNode::Handle link=parse_value_node(dynamic_cast<xmlpp::Element*>(*iter),canvas);
-
-                       if(!link)
+                       catch(Exception::IDNotFound)
                        {
-                               error((*iter),"Parse of ValueNode failed");
+                               error(element,"Unable to resolve " + id);
                        }
-                       else
-                       if(!value_node->set_link(index,link))
+                       catch(Exception::FileNotFound)
                        {
-                               //error(dynamic_cast<xmlpp::Element*>(*iter),strprintf("Unable to connect value node ('%s' of type '%s') to link %d",link->get_name().c_str(),ValueBase::type_name(link->get_type()).c_str(),index));
-                               error(element,strprintf("Unable to connect value node ('%s' of type '%s') to link %d",link->get_name().c_str(),ValueBase::type_name(link->get_type()).c_str(),index));
+                               error(element,"Unable to open file referenced in " + id);
                        }
-
-                       // \todo do a search for more elements and warn if they are found
-
-               }
-               catch(Exception::BadLinkName)
-               {
-                       error_unexpected_element(child,child->get_name());
-               }
-               catch(...)
-               {
-                       error(child,strprintf(_("Unknown Exception thrown when working on element \"%s\""),child->get_name().c_str()));
-                       throw;
-               }
-       }
-
-       return value_node;
-}
-
-handle<ValueNode_Composite>
-CanvasParser::parse_composite(xmlpp::Element *element,Canvas::Handle canvas)
-{
-       assert(element->get_name()=="composite");
-
-       if(!element->get_attribute("type"))
-       {
-               error(element,"Missing attribute \"type\" in <composite>");
-               return handle<ValueNode_Composite>();
-       }
-
-       ValueBase::Type type=ValueBase::ident_type(element->get_attribute("type")->get_value());
-
-       if(!type)
-       {
-               error(element,"Bad type in <composite>");
-               return handle<ValueNode_Composite>();
-       }
-
-       handle<ValueNode_Composite> value_node=ValueNode_Composite::create(type);
-       handle<ValueNode> c[6];
-
-       if(!value_node)
-       {
-               error(element,strprintf(_("Unable to create <composite>")));
-               return handle<ValueNode_Composite>();
-       }
-
-       int i;
-
-       for(i=0;i<value_node->link_count();i++)
-       {
-               string name=strprintf("c%d",i+1);
-               if(c[i])
-               {
-                       error(element,name+" was already defined in <composite>");
-                       continue;
-               }
-               if(element->get_attribute(name))
-               {
-                       c[i]=canvas->surefind_value_node(element->get_attribute(name)->get_value());
-                       if(c[i])
+                       catch(...)
                        {
-                               if(!value_node->set_link(i,c[i]))
-                               {
-                                       error(element,'"'+name+"\" attribute in <composite> has bad type");
-                               }
+                               error(element,strprintf(_("Unknown Exception thrown when referencing ValueNode \"%s\""), id.c_str()));
+                               throw;
                        }
-                       else
-                               error(element,'"'+name+"\" attribute in <composite> references unknown ID");
                }
        }
 
-       xmlpp::Element::NodeList list = element->get_children();
-       for(xmlpp::Element::NodeList::iterator iter = list.begin(); iter != list.end(); ++iter)
+       // handle inline valuenodes
        {
-               xmlpp::Element *child(dynamic_cast<xmlpp::Element*>(*iter));
-               if(!child)
-                       continue;
-               else
-               for(i=0;i<value_node->link_count();i++)
+               int index;
+               String child_name;
+               xmlpp::Element::NodeList list = element->get_children();
+               for(xmlpp::Element::NodeList::iterator iter = list.begin(); iter != list.end(); ++iter)
                {
-                       string name=strprintf("c%d",i+1);
-                       if(child->get_name()==name)
+                       xmlpp::Element *child(dynamic_cast<xmlpp::Element*>(*iter));
+                       try
                        {
-                               if(c[i])
+                               if(!child)
+                                       continue;
+
+                               child_name = child->get_name();
+
+                               index = value_node->get_link_index_from_name(child_name);
+
+                               if(c[index])
                                {
-                                       error(child,name+" was already defined in <composite>");
+                                       error(child, strprintf(_("'%s' was already defined in <%s>"),
+                                                                                  child_name.c_str(),
+                                                                                  element->get_name().c_str()));
                                        break;
                                }
 
@@ -1448,63 +1235,60 @@ CanvasParser::parse_composite(xmlpp::Element *element,Canvas::Handle canvas)
 
                                if(iter==list.end())
                                {
-                                       error(child,strprintf(_("<%s> is missing its contents"),name.c_str()));
-                                       break;
+                                       error(child,strprintf(_("element <%s> is missing its contents"),
+                                                                                 child_name.c_str()));
+                                       continue;
                                }
 
-                               c[i]=parse_value_node(dynamic_cast<xmlpp::Element*>(*iter),canvas);
+                               c[index]=parse_value_node(dynamic_cast<xmlpp::Element*>(*iter),canvas);
 
-                               if(!c[i])
+                               if(!c[index])
                                {
-                                       error((*iter),"Parse of "+name+" ValueNode failed");
-                                       break;
+                                       error((*iter),strprintf(_("Parse of '%s' failed"),
+                                                                                       child_name.c_str()));
+                                       continue;
                                }
 
-                               if(!value_node->set_link(i,c[i]))
+                               if(!value_node->set_link(index,c[index]))
                                {
-                                       error(child,strprintf(_("<%s> has a bad value"),name.c_str()));
-                                       break;
+                                       error(child,strprintf(_("Unable to connect value node ('%s' of type '%s') to link %d (%s)"),
+                                                                                 c[index]->get_name().c_str(),
+                                                                                 ValueBase::type_local_name(c[index]->get_type()).c_str(),
+                                                                                 index,
+                                                                                 value_node->link_name(index).c_str()));
+                                       continue;
                                }
 
                                // \todo do a search for more elements and warn if they are found
-                               break;
+
+                               // printf("  <%s> set link %d (%s) using inline value\n", element->get_name().c_str(), index, child_name.c_str());
+                       }
+                       catch(Exception::BadLinkName)
+                       {
+                               warning(child, strprintf("Bad link name for <%s>", element->get_name().c_str()));
+                       }
+                       catch(...)
+                       {
+                               error(child, strprintf(_("Unknown Exception thrown when working on element \"%s\""),child_name.c_str()));
+                               throw;
                        }
                }
-               // somewhat of a hack, but it works
-               if(i==value_node->link_count()) error_unexpected_element(child,child->get_name());
        }
 
-       switch(value_node->link_count())
+       for (int i = 0; i < value_node->link_count(); i++)
        {
-       case 1:
-               if(!value_node->get_link(0))
-               {
-                       error(element,"<composite> is missing parameters");
-                       return handle<ValueNode_Composite>();
-               }
-               break;
-       case 2:
-               if(!value_node->get_link(0) ||!value_node->get_link(1))
-               {
-                       error(element,"<composite> is missing parameters");
-                       return handle<ValueNode_Composite>();
-               }
-               break;
-       case 3:
-               if(!value_node->get_link(0) ||!value_node->get_link(1) ||!value_node->get_link(2))
-               {
-                       error(element,"<composite> is missing parameters");
-                       return handle<ValueNode_Composite>();
-               }
-               break;
-       case 4:
-               if(!value_node->get_link(0) ||!value_node->get_link(1) ||!value_node->get_link(2) ||!value_node->get_link(3))
+               if (!c[i] &&
+                       // the 'width' parameter of <stripes> wasn't always present, so it won't be in old .sif files
+                       !(element->get_name() == "stripes" && value_node->link_name(i) == "width"))
                {
-                       error(element,"<composite> is missing parameters");
-                       return handle<ValueNode_Composite>();
+                       error(element, strprintf(_("<%s> is missing link %d (%s)"),
+                                                                        element->get_name().c_str(),
+                                                                        i,
+                                                                        value_node->link_name(i).c_str()));
+                       return 0;
                }
-               break;
-    }
+       }
+
        return value_node;
 }
 
@@ -1678,6 +1462,7 @@ CanvasParser::parse_dynamic_list(xmlpp::Element *element,Canvas::Handle canvas)
 
                        if(child->get_attribute("use"))
                        {
+                               // \todo does this need to be able to read 'use="canvas"', like waypoints can now?  (see 'surefind_canvas' in this file)
                                string id=child->get_attribute("use")->get_value();
                                try
                                {
@@ -1738,7 +1523,7 @@ CanvasParser::parse_value_node(xmlpp::Element *element,Canvas::Handle canvas)
                        return value_node;
        }
 
-       // If ValueBase::ident_type() recognises the name, then we know it's a ValueBase
+       // If ValueBase::ident_type() recognizes the name, then we know it's a ValueBase
        if(element->get_name()!="canvas" && ValueBase::ident_type(element->get_name()))
        {
                ValueBase data=parse_value(element,canvas);
@@ -1760,36 +1545,30 @@ CanvasParser::parse_value_node(xmlpp::Element *element,Canvas::Handle canvas)
        if(element->get_name()=="hermite" || element->get_name()=="animated")
                value_node=parse_animated(element,canvas);
        else
-       if(element->get_name()=="subtract")
-               value_node=parse_subtract(element,canvas);
-       else
-       if(element->get_name()=="composite")
-               value_node=parse_composite(element,canvas);
-       else
        if(element->get_name()=="dynamic_list")
                value_node=parse_dynamic_list(element,canvas);
        else
        if(element->get_name()=="bline") // This is not a typo. The dynamic list parser will parse a bline.
                value_node=parse_dynamic_list(element,canvas);
        else
-       if(element->get_name()=="timed_swap")
-               value_node=parse_timedswap(element,canvas);
-       else
        if(LinkableValueNode::book().count(element->get_name()))
+       {
                value_node=parse_linkable_value_node(element,canvas);
+               if (!value_node) value_node = PlaceholderValueNode::create();
+       }
        else
        if(element->get_name()=="canvas")
                value_node=ValueNode_Const::create(parse_canvas(element,canvas,true));
        else
        {
                error_unexpected_element(element,element->get_name());
-               error(element, "Expected a ValueNode");
+               error(element, strprintf(_("Expected a ValueNode.  Refer to '%s'"),
+                                                                VALUENODE_COMPATIBILITY_URL));
+               value_node=PlaceholderValueNode::create();
        }
 
-
        value_node->set_root_canvas(canvas->get_root());
 
-
        // If we were successful, and our element has
        // an ID attribute, go ahead and add it to the
        // value_node list
@@ -1868,7 +1647,7 @@ CanvasParser::parse_layer(xmlpp::Element *element,Canvas::Handle canvas)
        {
                String version(element->get_attribute("version")->get_value());
                if(version>layer->get_version())
-                       warning(element,_("Installed layer version is larger than layer version in file"));
+                       warning(element,_("Installed layer version is smaller than layer version in file"));
                if(version!=layer->get_version())
                        layer->set_version(version);
        }
@@ -1915,7 +1694,9 @@ CanvasParser::parse_layer(xmlpp::Element *element,Canvas::Handle canvas)
 
                                String str=     child->get_attribute("use")->get_value();
 
-                               if(layer->get_param(param_name).get_type()==ValueBase::TYPE_CANVAS)
+                               if (str.empty())
+                                       error(child,_("Empty use=\"\" value in <param>"));
+                               else if(layer->get_param(param_name).get_type()==ValueBase::TYPE_CANVAS)
                                {
                                        if(!layer->set_param(param_name,canvas->surefind_canvas(str)))
                                                error((*iter),_("Layer rejected canvas link"));
@@ -1950,7 +1731,7 @@ CanvasParser::parse_layer(xmlpp::Element *element,Canvas::Handle canvas)
                                continue;
                        }
 
-                       // If we recognise the element name as a
+                       // If we recognize the element name as a
                        // ValueBase, then treat is at one
                        if(/*(*iter)->get_name()!="canvas" && */ValueBase::ident_type((*iter)->get_name()) && !dynamic_cast<xmlpp::Element*>(*iter)->get_attribute("guid"))
                        {
@@ -2049,6 +1830,11 @@ CanvasParser::parse_canvas(xmlpp::Element *element,Canvas::Handle parent,bool in
                        canvas->set_guid(guid);
        }
 
+       if(element->get_attribute("version"))
+               canvas->set_version(element->get_attribute("version")->get_value());
+       else if(parent)
+               canvas->set_version(parent->get_version());
+
        if(element->get_attribute("width"))
                canvas->rend_desc().set_w(atoi(element->get_attribute("width")->get_value().c_str()));
 
@@ -2183,7 +1969,7 @@ CanvasParser::parse_canvas(xmlpp::Element *element,Canvas::Handle parent,bool in
 
                                // If we don't have any name, warn
                                if(list.empty())
-                                       warning(child,_("blank \"name\" entitity"));
+                                       warning(child,_("blank \"name\" entity"));
 
                                string tmp;
                                for(xmlpp::Element::NodeList::iterator iter = list.begin(); iter != list.end(); ++iter)
@@ -2198,7 +1984,7 @@ CanvasParser::parse_canvas(xmlpp::Element *element,Canvas::Handle parent,bool in
 
                                // If we don't have any description, warn
                                if(list.empty())
-                                       warning(child,_("blank \"desc\" entitity"));
+                                       warning(child,_("blank \"desc\" entity"));
 
                                string tmp;
                                for(xmlpp::Element::NodeList::iterator iter = list.begin(); iter != list.end(); ++iter)
@@ -2213,7 +1999,7 @@ CanvasParser::parse_canvas(xmlpp::Element *element,Canvas::Handle parent,bool in
 
                                // If we don't have any description, warn
                                if(list.empty())
-                                       warning(child,_("blank \"author\" entitity"));
+                                       warning(child,_("blank \"author\" entity"));
 
                                string tmp;
                                for(xmlpp::Element::NodeList::iterator iter = list.begin(); iter != list.end(); ++iter)
@@ -2238,9 +2024,20 @@ CanvasParser::parse_canvas(xmlpp::Element *element,Canvas::Handle parent,bool in
 
        if(canvas->value_node_list().placeholder_count())
        {
-               error(element,strprintf(_("Canvas %s has undefined ValueNodes"),canvas->get_id().c_str()));
+               String nodes;
+               for (ValueNodeList::const_iterator iter = canvas->value_node_list().begin(); iter != canvas->value_node_list().end(); iter++)
+                       if(PlaceholderValueNode::Handle::cast_dynamic(*iter))
+                       {
+                               if (nodes != "") nodes += ", ";
+                               nodes += "'" + (*iter)->get_id() + "'";
+                       }
+               error(element,strprintf(_("Canvas '%s' has undefined %s: %s"),
+                                                               canvas->get_id().c_str(),
+                                                               canvas->value_node_list().placeholder_count() == 1 ? _("ValueNode") : _("ValueNodes"),
+                                                               nodes.c_str()));
        }
 
+       canvas->set_version(CURRENT_CANVAS_VERSION);
        return canvas;
 }
 
@@ -2253,7 +2050,6 @@ CanvasParser::parse_from_file(const String &file)
 Canvas::Handle
 CanvasParser::parse_from_file_as(const String &file_,const String &as_)
 {
-       CHECK_EXPIRE_TIME();
        try
        {
         ChangeLocale change_locale(LC_NUMERIC, "C");
@@ -2314,8 +2110,6 @@ CanvasParser::parse_from_file_as(const String &file_,const String &as_)
 Canvas::Handle
 CanvasParser::parse_from_string(const String &data)
 {
-       CHECK_EXPIRE_TIME();
-
        try
        {
         ChangeLocale change_locale(LC_NUMERIC, "C");