//Input: Light list, graphics g, Physical object, screen index, medium index
//Output: Change the Light list to the path casued by the Medium
public static void MediumAlgoritem(List <Light> lightList, Graphics g, PhysicalObject obj, double n1, double n2)
{
Light last = lightList[lightList.Count - 1];
PointF pi = last.pi;
PointF pf = last.pf;
PointF firstPoint = new PointF(pi.X, pi.Y);
Color lightColor = last.LightColor;
Region mediumReg = obj.GetRegion();
Region rayReg = last.GetRegion();
double angle = last.GetAngle();
mediumReg.Intersect(rayReg); //Intersect area of lens and the last light
if (!mediumReg.IsEmpty(g))
{
PointF hit = GetHitPoint(pf, mediumReg, g);
bool oppSide = false, isCritical = false;
double alpha = 0, beta = 0, tempBeta = 0, criticalAngle = 0;//angles
//getting hiting angle using math
PointF[] points = obj.GetPoints();
Light first = new Light(firstPoint, hit);
Light second = new Light(firstPoint, hit);//need to modified
if (points.Length == 2)
{
second = new Light(points[0], points[1]);
}
alpha = 90 - MathHelper.AngleBetweenLights(first, second);
//
if ((firstPoint.X - hit.X) * (obj.X - hit.X) > 0)
{
oppSide = true;
}
//calculate critical angle
if (!oppSide)
{
if (n1 > n2)
{
criticalAngle = Math.Round(Math.Asin(n2 / n1) * 180 / Math.PI);
}
isCritical = criticalAngle != 0 && alpha >= criticalAngle;
}
else
{
if (n2 > n1)
{
criticalAngle = Math.Round(Math.Asin(n1 / n2) * 180 / Math.PI);
}
isCritical = criticalAngle != 0 && alpha >= criticalAngle;
}
//
if (isCritical)//act like a mirror
{
MirrorAlgoritem(lightList, g, obj);
}
else
{
if (!oppSide)
{
beta = (Math.Asin(n1 / n2 * Math.Sin(alpha * Math.PI / 180)) * 180 / Math.PI); //snal law
beta = Math.Round(beta);
tempBeta = beta; //save beta value
}
else //opposite side
{
beta = (Math.Asin(n2 / n1 * Math.Sin(alpha * Math.PI / 180)) * 180 / Math.PI); //snal law
tempBeta = Math.Round(beta); //save beta value
beta = 180 - Math.Round(beta);
}
//fix light direction
float dirction = (firstPoint.Y - hit.Y) / (firstPoint.X - hit.X);
dirction = Math.Abs(dirction) / dirction;
if (oppSide)
{
dirction *= -1;
}
if (dirction == 1)
{
beta = 360 - beta;
}
//
if (alpha % 90 != 0)
{
lightList[lightList.Count - 1] = new Light(firstPoint, hit, lightColor);//light from the start to the hit point
lightList.Add(new Light(hit, MathHelper.GetEndLight(hit, beta + obj.Angle), lightColor));
}
}
//give information to data class
if (Main_Form.highlightedIndex != -1)
{
PhysicalObject highlighted = Main_Form.objectsList[Main_Form.highlightedIndex];
if (highlighted == obj)
{
MediumInfo.alphaAngle = alpha;
MediumInfo.betaAngle = tempBeta;
MediumInfo.mediumIndex = n2;
MediumInfo.criticalAngle = criticalAngle;
}
}
}
}
//Input: Light list, graphics g and a Physical object
//Output: Change the Light list to the path casued by the Mirror
public static void MirrorAlgoritem(List <Light> lightList, Graphics g, PhysicalObject obj)
{
Light last = lightList[lightList.Count - 1];
PointF pi = last.pi;
PointF pf = last.pf;
PointF firstPoint = new PointF(pi.X, pi.Y);
Color lightColor = last.LightColor;
Region mirrorReg = obj.GetRegion();
Region rayReg = last.GetRegion();
double angle = last.GetAngle();
bool vertical = false;
mirrorReg.Intersect(rayReg); //Intersect area of lens and the last light
if (!mirrorReg.IsEmpty(g))
{
PointF hit = GetHitPoint(pf, mirrorReg, g);
lightList[lightList.Count - 1] = new Light(pi, hit, lightColor); //light from the start to the hit point
double alpha = 180 - (angle - 2 * obj.Angle);
//check if the light hiting the vertical part of the mirror
PointF[] points = obj.GetPoints();
if (points.Length == 4)
{
PointF p1 = points[0];
PointF p2 = points[1];
PointF p3 = points[2];
PointF p4 = points[3];
float x = hit.X;
float y = hit.Y;
bool check1 = x >= Math.Min(p1.X, p4.X) && x <= Math.Max(p1.X, p4.X) && y >= Math.Min(p1.Y, p4.Y) && y <= Math.Max(p1.Y, p4.Y);
bool check2 = x >= Math.Min(p2.X, p3.X) && x <= Math.Max(p2.X, p3.X) && y >= Math.Min(p2.Y, p3.Y) && y <= Math.Max(p2.Y, p3.Y);
vertical = check1 || check2;
if (vertical)
{
alpha += 180;
}
}
lightList.Add(new Light(hit, MathHelper.GetEndLight(hit, alpha), lightColor)); //light from the hit point farther
//draw image and give info
Color imageColor = Color.Blue;
Mirror mirror = obj as Mirror;
if (mirror != null && mirror.ShowImage)
{
//calc image
imageColor = mirror.ImageColor;
double beta = alpha + 180;
double radius = MathHelper.DistanceBetweenPointF(hit, firstPoint);
float height = (float)(radius * Math.Sin(beta * Math.PI / 180));
float width = (float)(radius * Math.Cos(beta * Math.PI / 180));
float addWidth = obj.X - hit.X;
float addHeight = obj.Y - hit.Y;
//
//draw image
PointF imagePoint = new PointF(obj.X + width + addWidth, obj.Y - height + addHeight);
double angleToRotate = obj.Angle;
if (angleToRotate >= 180 && angleToRotate <= 360)
{
angleToRotate = angleToRotate + 180;
}
imagePoint = MathHelper.RotatePointF(imagePoint, obj.CenterPoint, angleToRotate);
g.FillEllipse(new SolidBrush(imageColor), imagePoint.X - 5, imagePoint.Y - 5, 10, 10);
//
//give information to data class
if (Main_Form.highlightedIndex != -1)
{
PhysicalObject highlighted = Main_Form.objectsList[Main_Form.highlightedIndex];
if (highlighted == obj)
{
MirrorInfo.startPoint = firstPoint;
//MirrorInfo.imagePoint = imagePoint;
}
}
}
//
}
}
