public void InterpolatePoints( int divisions, TerrainNode terrain, float terrainOffset )
{
// If the points havn't been interpolated already and points exist to interpolate between
if (m_ControlPoints.Count > 0)
{
// Create a new list of positions
List<Vector3> interpolatedPositions = new List<Vector3>();
int maxPoints = (m_ControlPoints.Count - 1);
// Between each control point....
for (int i = 0; i < maxPoints; i++)
{
// Add the control point to the new list
interpolatedPositions.Add(m_ControlPoints[i]);
// ADd the specifed number of interpolated points
for (int j = 0; j < divisions; j++)
{
// Determine how far to interpolate
float amount = ((float)(j + 1) / (float)(divisions + 2));
// Find the position based on catmull-rom interpolation
Vector3 interpolation = CatMullRom3D(m_ControlPoints[Wrap((i - 1), maxPoints)],
m_ControlPoints[Wrap(i, maxPoints)],
m_ControlPoints[Wrap((i + 1), maxPoints)],
m_ControlPoints[Wrap((i + 2), maxPoints)],
amount);
// Check if a terrain node was passed in or not
if (terrain != null)
{
// If so then check this interpolated points height against
// the terrain heights and adjust accordingly
interpolation.Y = terrain.GetHeight(interpolation) + terrainOffset;
}
// Add the new point to the list
interpolatedPositions.Add(interpolation);
}
}
// Add the last point
interpolatedPositions.Add(m_ControlPoints[maxPoints]);
// Save the interpolated positions over the original positions
m_InterpolatedPoints = interpolatedPositions;
}
}
public Vector3 GetNextInterpolatedPosition(GameTime deltaTime, Vector3 position, float intervals, TerrainNode terrain)
{
Vector3 toRet = m_LastPosition;
if (m_ControlPoints.Count > 0)
{
int max = (m_ControlPoints.Count - 1);
// If the current interpolate value is greater than or equal to the value of "1" then the end of the path between these
// two control points has been reached so increase the control point index.
if (m_CurrentInterpolateValue >= 1)
{
m_CurrentInterpolateValue = 0;
if (m_ControlPointIndex < (m_ControlPoints.Count - 2))
m_ControlPointIndex++;
else
{
if (m_Loop)
m_ControlPointIndex = 0;
else
{
m_EndReached = true;
toRet = m_ControlPoints[max];
}
}
}
// Make sure the end hasn't been reached yet
if (!m_EndReached)
{
toRet = CatMullRom3D(m_ControlPoints[Wrap((m_ControlPointIndex - 1), max)],
m_ControlPoints[Wrap(m_ControlPointIndex, max)],
m_ControlPoints[Wrap((m_ControlPointIndex + 1), max)],
m_ControlPoints[Wrap((m_ControlPointIndex + 2), max)],
m_CurrentInterpolateValue);
// Increase the interpolate value by the speed * deltaTime
if (intervals <= 0)
intervals = 0;
m_CurrentInterpolateValue += (1 / intervals) * (float)deltaTime.ElapsedGameTime.TotalSeconds;
}
}
if (terrain != null)
toRet.Y = terrain.GetHeight(toRet);
// Set the last position to be returned ( if the end has been reached then it should set itself to what it already is
// and return the same value ( hence not move anywhere else
m_LastPosition = toRet;
return toRet;
}
public void AddControlPoints(List<Vector3> newPoints, TerrainNode terrain)
{
for (int i = 0; i < newPoints.Count; i++ )
{
Vector3 point = newPoints[i];
// If a terrain has been passed in, check the height of the terrain
// at the position the new point is at
if (terrain != null)
point.Y = terrain.GetHeight(point); // +newPoint.Y;
if (m_ControlPoints.Count > 0)
{
// Check whether to have the end point the same as the start or whether to just directly add a point
// Depends on looping or not
if (m_Loop)
m_ControlPoints.Insert((m_ControlPoints.Count - 1), point);
else
m_ControlPoints.Add(point);
}
else
{
m_ControlPoints.Add(point);
// If looping add the point again as the end point
if (m_Loop)
m_ControlPoints.Add(point);
}
}
}