public static void Draw(SpriteBatch spriteBatch)
{
foreach (SingleRay Ray in SingleRays)
{
Ray.Draw(spriteBatch);
}
foreach (Mirror Mirror in Mirrors)
{
Mirror.Draw(spriteBatch);
}
foreach (GlassPolygon GlassPolygon in GlassPolygons)
{
GlassPolygon.Draw(spriteBatch);
}
}
public static void Update(GameTime gameTime)
{
foreach (SingleRay Ray in SingleRays)
{
Ray.Update(gameTime);
}
foreach (Mirror Mirror in Mirrors)
{
Mirror.Update(gameTime);
}
foreach (GlassPolygon GlassPolygon in GlassPolygons)
{
GlassPolygon.Update(gameTime);
}
if (Keyboard.GetState().IsKeyDown(Keys.Right))
{
SingleRays[0].Angle -= 0.01;
}
if (Keyboard.GetState().IsKeyDown(Keys.Left))
{
SingleRays[0].Angle += 0.01;
}
}
public void Propagate(Vector Position, Vector Direction, Manipulator PreviousObject, bool InMaterial)
{
List <Tuple <Vector, Manipulator> > Hits = new List <Tuple <Vector, Manipulator> >();
Vector Vector = Direction * Config.RayLength;
//Raycast to all Mirrors
foreach (Mirror Mirror in World.Mirrors)
{
if (Mirror == PreviousObject)
{
continue;
}
double T = MathUtil.Cross(Position - Mirror.A, Vector) / MathUtil.Cross(Mirror.B - Mirror.A, Vector);
double U = MathUtil.Cross(Position - Mirror.A, Mirror.B - Mirror.A) / MathUtil.Cross(Mirror.B - Mirror.A, Vector);
Vector Hit = Mirror.A + (Mirror.B - Mirror.A) * T;
if (MathUtil.Cross(Mirror.B - Mirror.A, Vector) != 0 && 0 <= T && T <= 1 && 0 <= U && U <= 1)
{
Hits.Add(Tuple.Create(Hit, (Manipulator)Mirror));
}
}
//Raycast to all GlassPolygons
foreach (GlassPolygon GlassPolygon in World.GlassPolygons)
{
foreach (GlassPane GlassPane in GlassPolygon.Edges)
{
if (GlassPane == PreviousObject)
{
continue;
}
double T = MathUtil.Cross(Position - GlassPane.A, Vector) / MathUtil.Cross(GlassPane.B - GlassPane.A, Vector);
double U = MathUtil.Cross(Position - GlassPane.A, GlassPane.B - GlassPane.A) / MathUtil.Cross(GlassPane.B - GlassPane.A, Vector);
Vector Hit = GlassPane.A + (GlassPane.B - GlassPane.A) * T;
if (MathUtil.Cross(GlassPane.B - GlassPane.A, Vector) != 0 && 0 <= T && T <= 1 && 0 <= U && U <= 1)
{
Hits.Add(Tuple.Create(Hit, (Manipulator)GlassPane));
}
}
}
//If not hits, continue ray
if (Hits.Count == 0)
{
Segments.Add(new RaySegment(Position, Position + Vector));
}
//If any hits, find closest one and handle it
else
{
Tuple <Vector, Manipulator> Closest = Hits.OrderBy(x => (x.Item1 - Position).Magnitude).First();
//If hit Mirror, reflection
if (Closest.Item2 is Mirror)
{
Mirror Hit = Closest.Item2 as Mirror;
Vector Normal = new Vector((Hit.B.Y - Hit.A.Y), -(Hit.B.X - Hit.A.X));
Normal = Normal.Normalized;
Vector Reflection = Direction - 2 * (Direction.X * Normal.X + Direction.Y * Normal.Y) * Normal;
Segments.Add(new RaySegment(Position, Closest.Item1));
Propagate(Closest.Item1, Reflection, Hit, InMaterial);
return;
}
//If hit GlassPane, refraction
if (Closest.Item2 is GlassPane)
{
GlassPane Hit = Closest.Item2 as GlassPane;
Vector Normal = new Vector((Hit.B.Y - Hit.A.Y), -(Hit.B.X - Hit.A.X));
Normal = Normal.Normalized;
//Handle going in and out of materials
double OutAngle = 0;
double IndexA = 0;
double IndexB = 0;
if (InMaterial)
{
IndexA = Hit.RefractiveIndex;
IndexB = 1;
}
else
{
IndexA = 1;
IndexB = Hit.RefractiveIndex;
}
//If flipped
if (MathUtil.Dot(Normal, Direction) < 0)
{
Normal.X = -Normal.X;
Normal.Y = -Normal.Y;
double InAngle =
Math.Acos(MathUtil.Dot(Closest.Item1 - Position, Normal)
/ MathUtil.Magnitude(Closest.Item1 - Position)
* MathUtil.Magnitude(Normal));
double SinValue = Math.Sin(InAngle) * IndexA / IndexB;
//Total inner reflection
if (SinValue > 1)
{
Vector Reflection = Direction - 2 * (Direction.X * Normal.X + Direction.Y * Normal.Y) * Normal;
OutAngle = Math.Atan2(Reflection.Y, Reflection.X);
}
//Refraction
else
{
InMaterial = !InMaterial;
OutAngle = Math.Asin(SinValue);
if (MathUtil.Dot(Hit.B - Hit.A, Closest.Item1 - Position) > 0)
{
OutAngle = Math.Atan2(Normal.Y, Normal.X) - OutAngle;
}
else
{
OutAngle += Math.Atan2(Normal.Y, Normal.X);
}
}
}
else
{
double InAngle =
Math.Acos(MathUtil.Dot(Closest.Item1 - Position, Normal)
/ MathUtil.Magnitude(Closest.Item1 - Position)
* MathUtil.Magnitude(Normal));
double SinValue = Math.Sin(InAngle) * IndexA / IndexB;
//Total inner reflection
if (SinValue > 1)
{
Vector Reflection = Direction - 2 * (Direction.X * Normal.X + Direction.Y * Normal.Y) * Normal;
OutAngle = Math.Atan2(Reflection.Y, Reflection.X);
}
//Refraction
else
{
InMaterial = !InMaterial;
OutAngle = Math.Asin(SinValue);
if (MathUtil.Dot(Hit.B - Hit.A, Closest.Item1 - Position) > 0)
{
OutAngle += Math.Atan2(Normal.Y, Normal.X);
}
else
{
OutAngle = Math.Atan2(Normal.Y, Normal.X) - OutAngle;
}
}
}
Segments.Add(new RaySegment(Position, Closest.Item1));
Propagate(Closest.Item1, new Vector(Math.Cos(OutAngle), Math.Sin(OutAngle)), Hit, InMaterial);
}
}
}