/// <summary>
/// Find the index of the given generator.
/// </summary>
/// <returns></returns>
private static int FindGenIndex(RoadGenerator gen)
{
for (int i = 0; i < generators.Length; ++i)
{
if (gen == generators[i])
{
return(i);
}
}
/// If we didn't find it, fall back on the invisible plain path.
return(0);
}
/// <summary>
/// Build transforms from world space into section space. In section
/// space, the section rect is an axis aligned box dimensioned
/// edgeLength X CollWidth centered at (0,0).
/// </summary>
/// <param name="gen"></param>
protected void CacheCollisionXfms(RoadGenerator gen)
{
worldToSection = Matrix.Identity;
sectionToWorld = Matrix.Identity;
// Center at the point between the nodes
Vector2 nodeCenter = (Edge.Node1.Position2d + Edge.Node0.Position2d) * 0.5f;
sectionToWorld.M41 = nodeCenter.X;
sectionToWorld.M42 = nodeCenter.Y;
// Align the section's X axis with the axis between the nodes.
// Apply no scaling, so computations based on length can still
// be done using world space units.
Vector2 nodeAxis = Edge.Node1.Position2d - Edge.Node0.Position2d;
edgeLength = nodeAxis.Length();
if (edgeLength < 0.01f)
{
Vector3 position = edge.Node1.Position;
position.Y = edge.Node0.Position2d.Y + 0.01f;
edge.Node1.Position = position;
nodeAxis = edge.Node1.Position2d - edge.Node0.Position2d;
edgeLength = nodeAxis.Length();
}
nodeAxis /= edgeLength;
sectionToWorld.M11 = nodeAxis.X;
sectionToWorld.M12 = nodeAxis.Y;
sectionToWorld.M21 = -nodeAxis.Y;
sectionToWorld.M22 = nodeAxis.X;
// Rotation is just the transpose
worldToSection.M11 = sectionToWorld.M11;
worldToSection.M12 = sectionToWorld.M21;
worldToSection.M21 = sectionToWorld.M12;
worldToSection.M22 = sectionToWorld.M22;
// Translation is negated and rotated
worldToSection.M41 = -sectionToWorld.M41 * sectionToWorld.M11
- sectionToWorld.M42 * sectionToWorld.M12;
worldToSection.M42 = -sectionToWorld.M41 * sectionToWorld.M21
- sectionToWorld.M42 * sectionToWorld.M22;
}
/// <summary>
/// Constructor, takes in owning path, which this road represents.
/// </summary>
/// <param name="inPath"></param>
public Road(WayPoint.Path inPath)
{
generator = generators[genIndex];
path = inPath;
}
