From bf9f025daf1b4df71ab5ca895acb3075f3f6b5c7 Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Sun, 21 Mar 2010 19:47:43 +0000
Subject: [PATCH] Get the editor to generate S-bends

---
 src/Editor.cpp | 43 +++++++++++++++++++++++++++----------------
 src/SBend.cpp  | 11 +++++++++--
 2 files changed, 36 insertions(+), 18 deletions(-)

diff --git a/src/Editor.cpp b/src/Editor.cpp
index cba0431..ce41b19 100644
--- a/src/Editor.cpp
+++ b/src/Editor.cpp
@@ -68,6 +68,7 @@ private:
    void drawDraggedCurve(int xLength, int yLength);
    bool canConnect(const Point<int>& aFirstPoint,
       const Point<int>& aSecondPoint) const;
+   bool canPlaceTrack(ITrackSegmentPtr track);
    void dragBoxBounds(int& xMin, int& xMax, int &yMin, int& yMax) const;
    void deleteObjects();
    void plantTrees();
@@ -296,6 +297,24 @@ void Editor::drawDraggedStraight(const track::Direction& anAxis, int aLength)
    }
 }
 
+// True if a track segment could be placed in its present location
+bool Editor::canPlaceTrack(ITrackSegmentPtr track)
+{
+   vector<Point<int> > covered;
+   track->getEndpoints(covered);
+   track->getCovers(covered);
+   
+   for (vector<Point<int> >::iterator it = covered.begin();
+        it != covered.end(); ++it) {
+      if (map->isValidTrack(*it)) {
+         warn() << "Cannot place curve here";
+         return false;
+      }
+   }
+
+   return true;
+}
+
 // Called when the user has finished dragging a rectangle for track
 // Connect the beginning and end up in the simplest way possible
 void Editor::drawDraggedTrack()
@@ -390,8 +409,13 @@ void Editor::drawDraggedTrack()
    else if (ylen == 1)
       drawDraggedStraight(axis::X, xlen);
    else if (startDir == endDir) {
-      // An S-bend (not implemented)
-      warn() << "Sorry! No S-bends yet...";
+      // An S-bend
+      ITrackSegmentPtr track = makeSBend(startDir, xlen, ylen);
+      const Point<int> where = dragBegin;
+      track->setOrigin(where.x, where.y, map->heightAt(where));
+
+      if (canPlaceTrack(track))
+	 map->setTrackAt(where, track);
    }
    else {
       // Curves at the moment cannot be ellipses so lay track down
@@ -465,20 +489,7 @@ void Editor::drawDraggedTrack()
       ITrackSegmentPtr track = makeCurvedTrack(startAngle, endAngle, xlen);
       track->setOrigin(where.x, where.y, map->heightAt(where));
 
-      vector<Point<int> > exits;
-      track->getEndpoints(exits);
-
-      bool ok = true;
-      for (vector<Point<int> >::iterator it = exits.begin();
-	   it != exits.end(); ++it) {
-	 if (map->isValidTrack(*it)) {
-	    warn() << "Cannot place curve here";
-	    ok = false;
-	    break;
-	 }
-      }
-
-      if (ok)
+      if (canPlaceTrack(track))
 	 map->setTrackAt(where, track);
    }
 }
diff --git a/src/SBend.cpp b/src/SBend.cpp
index 8e56e30..079d73e 100644
--- a/src/SBend.cpp
+++ b/src/SBend.cpp
@@ -54,12 +54,19 @@ private:
    int x_, y_;
    int xOffset, yOffset;
    float height;
+   track::Direction axis;
 };
 
 SBend::SBend(track::Direction dir, int xoff, int yoff)
-   : x_(0), y_(0), xOffset(xoff), yOffset(yoff), height(0.0f)
+   : x_(0), y_(0),
+     xOffset(xoff), yOffset(yoff),
+     height(0.0f),
+     axis(dir)
 {
-
+   assert(xoff > 0);
+   assert(yoff > 0);
+   
+   debug() << "SBend axis=" << axis << " xoff=" << xoff << " yoff=" << yoff;
 }
 
 void SBend::render() const
-- 
2.39.2