From 9abd4c4ccfb3a867dccdcfbdd4bf8adb7f43eb52 Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Sun, 7 Jun 2009 18:31:22 +0100
Subject: [PATCH] Calculate endpoints of points

---
 src/Map.cpp           |  7 +++++
 src/Points.cpp        | 63 +++++++++++++++++++++++++++++++++++++++++--
 src/StraightTrack.cpp |  4 +--
 3 files changed, 69 insertions(+), 5 deletions(-)

diff --git a/src/Map.cpp b/src/Map.cpp
index aff48c5..22b6065 100644
--- a/src/Map.cpp
+++ b/src/Map.cpp
@@ -715,6 +715,13 @@ void Map::renderSector(IGraphicsPtr aContext, int id,
             glPopMatrix();
             
             tile.track->setMark();
+            
+            // Draw the endpoints for debugging
+            list<Point<int> > endpoints;
+            tile.track->get()->getEndpoints(endpoints);
+            for_each(endpoints.begin(), endpoints.end(),
+                     bind(&Map::highlightTile, this, aContext, placeholders::_1,
+                          make_tuple(0.9f, 0.1f, 0.1f)));
          }
 
          // Draw the station, if any
diff --git a/src/Points.cpp b/src/Points.cpp
index 893ffeb..b645f06 100644
--- a/src/Points.cpp
+++ b/src/Points.cpp
@@ -20,7 +20,10 @@
 #include "XMLBuilder.hpp"
 #include "ILogger.hpp"
 
+#include <cassert>
+
 #include <GL/gl.h>
+#include <boost/lexical_cast.hpp>
 
 // Forks in the track
 class Points : public ITrackSegment {
@@ -39,6 +42,9 @@ public:
                               const track::Direction& aDirection);
    xml::element toXml() const;
 private:
+   void transform(const track::Direction& aDirection, double aDelta) const;
+   void ensureValidDirection(track::Direction aDirection) const;
+   
    int myX, myY;
    track::Direction myAxis;
    bool amReflected;
@@ -93,25 +99,78 @@ double Points::segmentLength() const
    return 1.0;
 }
 
+void Points::transform(const track::Direction& aDirection,
+                       double aDelta) const
+{
+
+}
+
 ITrackSegment::TransformFunc
 Points::transformFunc(const track::Direction& aDirection) const
 {
+   using namespace placeholders;
+   
+   ensureValidDirection(aDirection);
    
+   return bind(&Points::transform, this, aDirection, _1);
+}
+
+void Points::ensureValidDirection(track::Direction aDirection) const
+{
+   if (!isValidDirection(aDirection))
+      throw runtime_error
+         ("Invalid direction on points: "
+          + boost::lexical_cast<string>(aDirection)
+          + " (should be parallel to "
+          + boost::lexical_cast<string>(myAxis) + ")");
 }
 
 bool Points::isValidDirection(const track::Direction& aDirection) const
 {
-   return true;
+   if (myAxis == axis::X || myAxis == -axis::X)
+      return aDirection == axis::X || -aDirection == axis::X;
+   else
+      return aDirection == axis::Y || -aDirection == axis::Y;
 }
 
 track::Connection Points::nextPosition(const track::Direction& aDirection) const
 {
-
+   ensureValidDirection(aDirection);
+   
+   if (aDirection == axis::X)
+      return make_pair(makePoint(myX + 1, myY), axis::X);
+   else if (aDirection == -axis::X)
+      return make_pair(makePoint(myX - 1, myY), -axis::X);
+   else if (aDirection == axis::Y)
+      return make_pair(makePoint(myX, myY + 1), axis::Y);
+   else if (aDirection == -axis::Y)
+      return make_pair(makePoint(myX, myY - 1), -axis::Y);
+   else
+      assert(false);
 }
 
 void Points::getEndpoints(std::list<Point<int> >& aList) const
 {
    aList.push_back(makePoint(myX, myY));
+
+   const int reflect = amReflected ? -1 : 1;
+
+   if (myAxis == axis::X) {
+      aList.push_back(makePoint(myX + 2, myY));
+      aList.push_back(makePoint(myX + 2, myY + 1*reflect));
+   }
+   else if (myAxis == -axis::X) {
+      aList.push_back(makePoint(myX - 2, myY));
+      aList.push_back(makePoint(myX - 2, myY - 1*reflect));
+   }
+   else if (myAxis == axis::Y) {
+      aList.push_back(makePoint(myX, myY + 2));
+      aList.push_back(makePoint(myX - 1*reflect, myY + 2));
+   }
+   else if (myAxis == -axis::Y) {
+      aList.push_back(makePoint(myX, myY - 2));
+      aList.push_back(makePoint(myX + 1*reflect, myY - 2));
+   }
 }
 
 ITrackSegmentPtr Points::mergeExit(const Point<int>& aPoint,
diff --git a/src/StraightTrack.cpp b/src/StraightTrack.cpp
index 28d2618..533c715 100644
--- a/src/StraightTrack.cpp
+++ b/src/StraightTrack.cpp
@@ -27,9 +27,7 @@
 #include <GL/glu.h>
 #include <boost/lexical_cast.hpp>
 
-using namespace std;
-using namespace std::tr1;
-using namespace std::tr1::placeholders;
+using namespace placeholders;
 using namespace boost;
 using namespace track;
 
-- 
2.39.2