From 97996a8b065d0c462b0a847fc9b7a301235666da Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Tue, 2 Mar 2010 21:25:21 +0000
Subject: [PATCH] Start getting the train to go uphill

---
 include/BezierCurve.hpp |  6 ++++++
 src/CrossoverTrack.cpp  |  2 +-
 src/CurvedTrack.cpp     |  2 +-
 src/Points.cpp          |  2 +-
 src/SlopeTrack.cpp      | 30 ++++++++++++++++++++++--------
 src/StraightTrack.cpp   |  2 +-
 6 files changed, 32 insertions(+), 12 deletions(-)

diff --git a/include/BezierCurve.hpp b/include/BezierCurve.hpp
index 004f48f..ff79f30 100644
--- a/include/BezierCurve.hpp
+++ b/include/BezierCurve.hpp
@@ -50,6 +50,12 @@ struct BezierCurve {
       }
    }
 
+   BezierCurve()
+      : length(0)
+   {
+
+   }
+
    Vector<T> operator()(T t) const
    {
       return makeVector
diff --git a/src/CrossoverTrack.cpp b/src/CrossoverTrack.cpp
index cfff014..aa4fc4b 100644
--- a/src/CrossoverTrack.cpp
+++ b/src/CrossoverTrack.cpp
@@ -147,7 +147,7 @@ void CrossoverTrack::transform(const track::TravelToken& aToken,
    const double yTrans = dir == axis::Y ? aDelta : 0;
 
    glTranslated(static_cast<double>(myX) + xTrans,
-      0.0,
+      height,
       static_cast<double>(myY) + yTrans);
 
    if (dir == axis::Y)
diff --git a/src/CurvedTrack.cpp b/src/CurvedTrack.cpp
index 80e4c52..5e23bb1 100644
--- a/src/CurvedTrack.cpp
+++ b/src/CurvedTrack.cpp
@@ -114,7 +114,7 @@ void CurvedTrack::transform(const track::TravelToken& aToken, double aDelta) con
    assert(aDelta < segmentLength(aToken));
    
    glTranslated(static_cast<double>(origin.x),
-      0.0,
+      height,
       static_cast<double>(origin.y));
 
    transformToOrigin(baseRadius, startAngle);
diff --git a/src/Points.cpp b/src/Points.cpp
index 8ed8a32..41234e5 100644
--- a/src/Points.cpp
+++ b/src/Points.cpp
@@ -287,7 +287,7 @@ void Points::transform(const track::TravelToken& aToken, double aDelta) const
          : (myAxis == -axis::Y ? -aDelta : 0.0);
       
       glTranslatef(static_cast<double>(myX) + xTrans,
-         0.0,
+         height,
          static_cast<double>(myY) + yTrans);
       
       if (myAxis == axis::Y || myAxis == -axis::Y)
diff --git a/src/SlopeTrack.cpp b/src/SlopeTrack.cpp
index 978f2cf..6ea5833 100644
--- a/src/SlopeTrack.cpp
+++ b/src/SlopeTrack.cpp
@@ -65,6 +65,7 @@ private:
    track::Direction axis;
    float length;
    bool flip;
+   BezierCurve<float> curve;
 };
 
 SlopeTrack::SlopeTrack(track::Direction axis, Vector<float> slope,
@@ -97,7 +98,7 @@ SlopeTrack::SlopeTrack(track::Direction axis, Vector<float> slope,
       
    debug() << p1 << " " << p2 << " " << p3 << " " << p4;
    
-   BezierCurve<float> curve = makeBezierCurve(p1, p2, p3, p4);
+   curve = makeBezierCurve(p1, p2, p3, p4);
    length = curve.length;
 
    // TODO: we should cache these
@@ -185,17 +186,30 @@ track::TravelToken SlopeTrack::getTravelToken(track::Position pos,
 
 void SlopeTrack::transform(const track::TravelToken& token, double delta) const
 {
-   assert(delta < 1.0);
+   assert(delta < length);
 
-   if (token.direction == -axis)
-      delta = 1.0 - delta;
+   //if (token.direction == -axis)
+   //   delta = length - delta;
+
+   const float curveDelta = delta / length;
+
+   const Vector<float> curveValue = curve(curveDelta);
 
-   const double xTrans = axis == axis::X ? delta : 0;
-   const double yTrans = axis == axis::Y ? delta : 0;
+   // const double xTrans = axis == axis::X ? delta : 0;
+   // const double yTrans = axis == axis::Y ? delta : 0;
 
+   // const float along =
+   //   token.direction == -axis ? 1.0f - curveValue.x : curveValue.x;
+
+   const float along = curveValue.x;
+   
+   const float xTrans = axis == axis::X ? along : 0.0f;
+   const float yTrans = curveValue.y;
+   const float zTrans = axis == axis::Y ? along : 0.0f;
+   
    glTranslated(static_cast<double>(origin.x) + xTrans,
-      0.0,
-      static_cast<double>(origin.y) + yTrans);
+      height + yTrans,
+      static_cast<double>(origin.y) + zTrans);
 
    if (axis == axis::Y)
       glRotated(-90.0, 0.0, 1.0, 0.0);
diff --git a/src/StraightTrack.cpp b/src/StraightTrack.cpp
index 4081526..ec9acf6 100644
--- a/src/StraightTrack.cpp
+++ b/src/StraightTrack.cpp
@@ -114,7 +114,7 @@ void StraightTrack::transform(const track::TravelToken& aToken,
    const double yTrans = direction == axis::Y ? aDelta : 0;
 
    glTranslated(static_cast<double>(origin.x) + xTrans,
-      0.0,
+      height,
       static_cast<double>(origin.y) + yTrans);
 
    if (direction == axis::Y)
-- 
2.39.2