private static double FindIntersection(IList <RendererHelper.StarMoved> stars, RendererHelper.StarMoved skipStar, Geometry.Line ray, out RendererHelper.StarMoved outStar)
{
return(FindIntersection(stars, skipStar, ray.origin, ray.vector, out outStar));
}
public void Render(List <RendererHelper.StarMoved> stars, DistPoint[,] dists, double[] flux, int fluxIndex)
{
DistPoint.Reset(dists);
double width, height;
RendererHelper.GetBoundingBox(stars, out width, out height);
// +++ HACK
//width = 45;
//height = 10;
// -- HACK
double viewAngle = 0;
int xxmax = dists.GetLength(0);
int yymax = dists.GetLength(1);
double zoomX = xxmax / width;
double zoomY = yymax / height;
double zoom = Math.Min(zoomX, zoomY);
int xxoffs = xxmax / 2;
int yyoffs = yymax / 2;
double brightness = 0;
double wdy = Math.Cos(viewAngle);
double wdz = Math.Sin(viewAngle);
double woy = -200 * wdy;
double woz = -200 * wdz;
for (int yy = 0; yy < yymax; yy++)
{
double y = (yy - yyoffs) / zoom;
for (int xx = 0; xx < xxmax; xx++)
{
Geometry.Line ray = new Geometry.Line(
origin: new Geometry.Point(
x: (xx - xxoffs) / zoom,
y: woy - y * wdz,
z: woz + y * wdy
),
vector: new Geometry.Vector(
dx: 0,
dy: wdy,
dz: wdz
)
);
RendererHelper.StarMoved star;
double t = FindIntersection(stars, null, ray, out star);
if (star != null)
{
dists[xx, yy].dist = t;
Geometry.Point hitPoint = ray.GetPoint(t);
Geometry.Vector normal = star.sphere.GetNormal(hitPoint);
Geometry.Line view = new Geometry.Line(hitPoint, normal);
double cosTheta = -Geometry.DotProduct(ray.vector, normal); // should be Geometry.CosAngle(...) but as both vectors are normalized this is the same
double br = Physics.LimbDarkening(star.exitance, cosTheta);
// ILLUMINATION
{
foreach (RendererHelper.StarMoved star2 in stars)
{
if (star2 == star)
{
continue;
}
Geometry.Vector toStar2 = new Geometry.Vector(hitPoint, star2.center);
double toStar2Size = toStar2.Size;
toStar2 = toStar2.Normalize();
double dp = Geometry.DotProduct(toStar2, normal);
if (dp > 0)
{
double shadow = double.PositiveInfinity;
foreach (RendererHelper.StarMoved star3 in stars)
{
if ((star3 == star) || (star3 == star2))
{
continue;
}
double p = Geometry.GetIntersectionMin(hitPoint, toStar2, star3.sphere);
if (double.IsNaN(p) || double.IsInfinity(p))
{
continue;
}
if (p < shadow)
{
shadow = p;
}
}
double d = toStar2Size - star2.radius;
//if ((d > star2.radius / 10) && (d < shadow))
if (d < shadow)
{
br += star2.exitance * dp / (d * d);
}
}
#region failed attempt to count in nonzero radius
/*
* failed attempt to count in nonzero radius
*
* Geometry.Point star2Closest = view.GetClosestPointTo(star2.center);
* Geometry.Vector star2ToClosest = new Geometry.Vector(star2.center, star2Closest);
* double u = Math.Min(star2ToClosest.Size, star2.radius);
* Geometry.Point star2ViewClosest = new Geometry.Line(star2.center, star2ToClosest).GetPoint(u);
* Geometry.Vector toStar2ViewClosest = new Geometry.Vector(hitPoint, star2ViewClosest);
* toStar2ViewClosest.Normalize();
* double dp2 = -Geometry.DotProduct(toStar2ViewClosest, normal);
* if (dp2 > 0)
* {
* double p1;
* double p2;
* Geometry.Line viewToClosest = new Geometry.Line(hitPoint, toStar2ViewClosest);
* int results = Geometry.GetIntersections(viewToClosest, star2.sphere, out p1, out p2);
* if (results > 0)
* {
* double p;
* if (p1 < 0)
* { p = p2; }
* else if (p2 < 0)
* { p = p1; }
* else
* { p = Math.Min(p1, p2); }
*
* if (p > 0)
* {
* br += star2.exitance;// / (p * p));
* }
* }
* }
*/
#endregion
}
}
#region NORMAL ILLUMINATION
/*
* {
* Geometry.Sphere star2;
* double t2 = FindIntersection(stars, star, star.origin, normal, out star2);
* if (star2 != null)
* { br += star2.exitance / (t2 * t2); }
* }
*/
#endregion
#region REFLECTION
/*
* {
* var reflection = new Geometry.Vector(normal);
* reflection.Multiply(2 * -Geometry.DotProduct(ray.vector, normal));
* reflection.Add(ray.vector);
*
* RendererHelper.StarMoved star2;
* double t2 = FindIntersection(stars, star, hitPoint, reflection, out star2);
* if (star2 != null)
* { br += star2.exitance / (t2 * t2); }
* }
*/
#endregion
#region REFRACTION
/*
* {
* double c1 = -Geometry.DotProduct(ray.vector, normal);
* double n = 1.3;
* double c2 = Math.Sqrt(1 - n * n * (1 - c1 * c1));
* var V = new Geometry.Vector(ray.vector);
* V.Multiply(n);
* var refraction = new Geometry.Vector(normal);
* refraction.Multiply(n * c1 - c2);
* refraction.Add(V);
*
* Star star2;
* double t2 = FindIntersection(stars, star, hitPoint, refraction, out star2);
* if (star2 != null)
* { br += star2.exitance / (t2 * t2); }
* }
*/
#endregion
dists[xx, yy].brightness = br;
brightness += br;
}
}
}
flux[fluxIndex] = brightness / (zoom * zoom);
}