// cheap ;)
public void SetScreenDimensions(int width, int height)
{
double factor = width / (2.0 * height);
ViewPaneWidthVector /= 2;
ViewPaneEdge += ViewPaneWidthVector;
ViewPaneWidthVector = ViewPaneWidthVector.Normalize();
ViewPaneWidthVector *= factor;
ViewPaneEdge -= ViewPaneWidthVector;
ViewPaneWidthVector *= 2;
}
/**
* Refraction
*
* @param incoming incoming vector
* @param normal normal of the reflectio area
* @param outgoing result of the computation
*/
public static Vect3 RefractOn(this Vect3 incoming, Vect3 normal, double refractionIndex)
{
//test implementation - working but propably slow
Vect3 result = incoming.ProjectOnNormal(normal);
result = result / refractionIndex;
double quadLen = result.QuadLength();
if (quadLen >= 1) //total reflection
{
result = incoming.ReflectOn(normal);
}
else
{
result = result + (normal * -System.Math.Sqrt(1 - quadLen));
result = result.Normalize();
}
return(result);
}
public static Camera CreateCamera(Vect3 position, Vect3 viewPaneCenter, Vect3 camUp, double viewPaneWidth,
double viewPaneHeight)
{
var viewPaneHeightVector = camUp;
viewPaneHeightVector *= -viewPaneHeight;
Vect3 temp1 = position - viewPaneCenter;
Vect3 viewPaneWidthVector = temp1.CrossProduct(viewPaneHeightVector);
viewPaneWidthVector = viewPaneWidthVector.Normalize();
viewPaneWidthVector *= viewPaneWidth;
viewPaneWidthVector.CopyDataTo(ref temp1);
temp1 = temp1 / 2;
Vect3 viewPaneEdge = viewPaneCenter - temp1;
viewPaneHeightVector.CopyDataTo(ref temp1);
temp1 = temp1 / 2;
viewPaneEdge -= temp1;
return(new Camera(position, viewPaneEdge, viewPaneWidthVector, viewPaneHeightVector));
}
public static double InterpolateTriangleEdge(Vect3 v1, Vect3 v2, Vect3 v3, Vect3 point)
{
Vect3 v23N = v3 - v2;
v23N = v23N.Normalize();
Vect3 v21 = v1 - v2;
// ReSharper disable InconsistentNaming
Vect3 v1o = v21.ProjectOn(v23N); //punkt gegenüber der ecke v1 (o ... opposite)
// ReSharper restore InconsistentNaming
v1o -= v21;
double h1 = v1o.Length(); //höhe auf v1
v1o = v1o / h1; //normieren
Vect3 v1P = point - v1;
Vect3 p1 = v1P.ProjectOn(v1o); //projektion von v1p auf v1hn
return(1 - (p1.Length() / h1));
}
public override Vect3 GetNormalAt(Vect3 hitPoint)
{
Vect3 target = hitPoint - Position;
return(target.Normalize());
}
public static Vect3 GetCircumScribedCircleCenter(Vect3 a, Vect3 b, Vect3 c)
{
Vect3 mab = b - a;
Vect3 mac = c - a;
Vect3 normal = mab.CrossProduct(mac);
Vect3 dab = mab.CrossProduct(normal);
Vect3 dac = mac.CrossProduct(normal);
mab = a + mab / 2;
mac = a + mac / 2;
dab = dab.Normalize();
dac = dac.Normalize();
if (System.Math.Abs(dac.X) > Constants.EPS &&
System.Math.Abs(dac.Y) > Constants.EPS &&
System.Math.Abs(dab.X / dac.X - dab.Y / dac.Y) > Constants.EPS)
{
double x = ((mab.Y - mac.Y) / dac.Y - (mab.X - mac.X) / dac.X) / (dab.X / dac.X - dab.Y / dac.Y);
return(mab + dab * x);
}
if (System.Math.Abs(dac.X) > Constants.EPS &&
System.Math.Abs(dac.Z) > Constants.EPS &&
System.Math.Abs(dab.Z / dac.Z - dab.X / dac.X) > Constants.EPS)
{
double x = ((mab.X - mac.X) / dac.X - (mab.Z - mac.Z) / dac.Z) / (dab.Z / dac.Z - dab.X / dac.X);
return(mab + dab * x);
}
if (System.Math.Abs(dac.Y) > Constants.EPS &&
System.Math.Abs(dac.Z) > Constants.EPS &&
System.Math.Abs(dab.Y / dac.Y - dab.Z / dac.Z) > Constants.EPS)
{
double x = ((mab.Z - mac.Z) / dac.Z - (mab.Y - mac.Y) / dac.Y) / (dab.Y / dac.Y - dab.Z / dac.Z);
return(mab + dab * x);
}
if (System.Math.Abs(dab.Y) > Constants.EPS &&
System.Math.Abs(dab.X) > Constants.EPS &&
System.Math.Abs(dac.X / dab.X - dac.Y / dab.Y) > Constants.EPS)
{
double y = ((mac.Y - mab.Y) / dab.Y - (mac.X - mab.X) / dab.X) / (dac.X / dab.X - dac.Y / dab.Y);
return(mac + dac * y);
}
if (System.Math.Abs(dab.Z) > Constants.EPS &&
System.Math.Abs(dab.X) > Constants.EPS &&
System.Math.Abs(dac.Z / dab.Z - dac.X / dab.X) > Constants.EPS)
{
double y = ((mac.X - mab.X) / dab.X - (mac.Z - mab.Z) / dab.Z) / (dac.Z / dab.Z - dac.X / dab.X);
return(mac + dac * y);
}
if (System.Math.Abs(dab.Z) > Constants.EPS &&
System.Math.Abs(dab.Y) > Constants.EPS &&
System.Math.Abs(dac.Y / dab.Y - dac.Z / dab.Z) > Constants.EPS)
{
double y = ((mac.Z - mab.Z) / dab.Z - (mac.Y - mab.Y) / dab.Y) / (dac.Y / dab.Y - dac.Z / dab.Z);
return(mac + dac * y);
}
throw new Exception("implement more cases...");
}
