public Vector ReflectAndRefract(Shape3D obj, Ray ray, Vector intersect, Vector normal, int depth)
{
// var cVec = obj.material.Intersect(ray, intersect, normal, obj).ToVector();
var cVec = Vector.Build.Dense(3);
var lIntersect = intersect + (normal * 0.001f);
bool outside = Extensions.Dot3(ray.direction, normal) > 0.0f;
if (obj.material.kReflection > 0f)
{
var reflect = Extensions.Reflected(-ray.direction, normal).Normalize();
Ray r = new Ray(lIntersect, reflect);
SpawnRay(r, out var reflectColor, depth + 1);
cVec += (reflectColor.ToVector() * obj.material.kReflection);
}
if (obj.material.kTransmission > 0f)
{
var refract = Extensions.Refract(ray.direction, normal, airKt,
obj.material.kTransmission).Normalize();
var rO = outside ? intersect + (normal * 0.001f) : intersect - (normal * 0.001f);
Ray r = new Ray(rO, refract);
SpawnRay(r, out var refractColor, depth + 1);
cVec += (refractColor.ToVector() * obj.material.kTransmission);
}
return(cVec);
}
public override bool Intersect(Ray ray, out Vector <float>[] intersection, out Vector <float>[] normal)
{
Shape3D closestT = null;
intersection = new Vector[1];
normal = new Vector[1];
float closestD = float.MaxValue;
int ti = 0;
foreach (Shape3D t in shapes)
{
if (t.Intersect(ray, out var i, out var n))
{
float dist = Math.Abs((ray.origin - i[0]).Length());
if (dist < closestD)
{
closestD = dist;
closestT = t;
intersection[0] = i[0];
normal[0] = n[0];
}
}
ti++;
}
return(closestT != null);
}
public static bool IntersectObjects(List <Shape3D> L, Ray ray, ref Shape3D hitObject, ref Vector intersect, ref Vector normal)
{
// run intersection test
Shape3D closestObj = null;
float? closestD = null;
if (hitObject != null)
{
closestObj = hitObject;
closestD = Math.Abs((ray.origin - intersect).Length());
}
foreach (Shape3D obj in L)
{
// if (obj.AABB.Intersect(ray, out var min, out var max))
// {
if (obj.Intersect(ray, out var i, out var n))
{
float dist = Math.Abs((ray.origin - i[0]).Length());
if (closestD == null || dist < closestD)
{
closestD = dist;
closestObj = obj;
intersect = i[0];
normal = n[0];
}
}
// }
}
if (closestObj != null)
{
hitObject = closestObj;
}
return(hitObject != null);
}
public bool InBounds(Shape3D s)
{
if (s is Triangle)
{
return(InBounds(s as Triangle));
}
if (s.AABB != null)
{
return(InBounds(s.AABB));
}
else
{
System.Console.WriteLine("no AABB");
return(false);
}
// else if (s is Sphere)
// {
// return InBounds(s as Sphere);
// }
// else if (s is Plane)
// {
// return InBounds(s as Plane);
// }
// else return false;
}
public static bool Traverse(Ray ray, Node node, ref Shape3D hitObject, ref Vector intersect, ref Vector normal, int depth = 0)
{
// System.Console.WriteLine("Traversing Depth: " + depth);
if (node is LeafNode)
{
var ln = node as LeafNode;
// if(ln.bounds.Intersect(ray, out var min, out var max))
IntersectObjects(ln.shapes, ray, ref hitObject, ref intersect, ref normal);
}
else
{
// traverse
var ax = node.partition.axis;
if (node.bounds.Intersect(ray, out var ad, out var bd))
{
var s = float.MaxValue;
if (node.partition.Intersect(ray, out var splitIntersect, out var n))
{
s = splitIntersect[0][ax];
}
float a, b;
a = ray.origin[ax] + (ray.direction[ax] * ad);
b = ray.origin[ax] + (ray.direction[ax] * bd);
if (a <= s)
{
if (b < s)
{
Traverse(ray, node.right, ref hitObject, ref intersect, ref normal, depth + 1);
}
else
{
if (b == s)
{
Traverse(ray, node.left, ref hitObject, ref intersect, ref normal, depth + 1);
Traverse(ray, node.right, ref hitObject, ref intersect, ref normal, depth + 1);
}
else
{
Traverse(ray, node.right, ref hitObject, ref intersect, ref normal, depth + 1);
Traverse(ray, node.left, ref hitObject, ref intersect, ref normal, depth + 1);
}
}
}
else
{
if (b > s)
{
Traverse(ray, node.left, ref hitObject, ref intersect, ref normal, depth + 1);
}
else
{
Traverse(ray, node.left, ref hitObject, ref intersect, ref normal, depth + 1);
Traverse(ray, node.right, ref hitObject, ref intersect, ref normal, depth + 1);
}
}
}
}
return(hitObject != null);
}
public Shape3D TraceRayKD(Ray ray, out Vector intersect, out Vector normal)
{
Shape3D hitObj = null;
intersect = null;
normal = null;
KDTree.Traverse(ray, tree, ref hitObj, ref intersect, ref normal);
return(hitObj);
}
public static ComplexObject LoadObjFile(string filename)
{
var factory = new ObjLoader.Loader.Loaders.ObjLoaderFactory();
var loader = factory.Create();
var fs = File.OpenRead(filename);
var result = loader.Load(fs);
List <Shape3D> objShapes = new List <Shape3D>();
var m = new BasicMaterial(Rgba32.Gray);
foreach (var g in result.Groups)
{
foreach (var f in g.Faces)
{
Vector[] verts = new Vector[f.Count];
for (var fv = 0; fv < f.Count; fv++)
{
var vx = result.Vertices[f[fv].VertexIndex - 1].X;
var vy = result.Vertices[f[fv].VertexIndex - 1].Y;
var vz = result.Vertices[f[fv].VertexIndex - 1].Z;
Vector vert = Vector.Build.DenseOfArray(new float[] { vx, vy, vz });
verts[fv] = vert;
}
Shape3D shape = null;
// Vector c = Vector.Build.Dense(3);
// foreach (Vector v in verts)
// {
// c += v;
// }
// c /= verts.Length;
// shape = new Sphere(c, 0.01f, m);
switch (f.Count)
{
case 3:
shape = new Triangle(verts, m);
break;
case 4:
shape = new Plane(verts, m);
break;
default:
shape = new Plane(verts, m);
break;
}
if (shape != null)
{
objShapes.Add(shape);
}
}
}
ComplexObject obj = new ComplexObject(objShapes, m);
return(obj);
}
public Material GetMaterial(Shape3D obj, Vector <float> intersection)
{
var tex = obj.GetTextureCoords(intersection);
float row = tex[1] / checksize;
float col = tex[0] / checksize;
if ((int)row % 2 == (int)col % 2)
{
return(material1);
}
else
{
return(material2);
}
}
public Vector ReflectAndRefractKD(Shape3D obj, Ray ray, Vector intersect, Vector normal, int depth)
{
var cVec = Vector.Build.Dense(3);
if (obj.material is LenseMaterial)
{
var bh = obj as BlackHole;
var sw_radius = bh.Sradius;
var ray_to_center = obj.center - ray.origin;
float tca = ray_to_center.DotProduct(ray.direction);
var p = ray.origin + (ray.direction * tca);
var d = (float)Math.Abs((p - obj.center).Length());
if (d < sw_radius)
{
return(cVec);
}
var a = (2 * sw_radius / d);
var rO = intersect - (normal * (0.001f));
var rotationMatrix = obj.GetRotationMatrixAboutAxis(normal.CrossProduct(ray.direction).Normalize(), a);
var refract = (rotationMatrix * ray.direction.GetVector4()).SubVector(0, 3).Normalize();
Ray r = new Ray(rO, refract);
SpawnRayKD(r, out var reflectColor, depth + 1);
cVec += (reflectColor.ToVector());
}
if (obj.material.kReflection > 0f)
{
var lIntersect = intersect + (normal * 0.001f);
var reflect = Extensions.Reflected(-ray.direction, normal).Normalize();
Ray r = new Ray(lIntersect, reflect);
SpawnRayKD(r, out var reflectColor, depth + 1);
cVec += (reflectColor.ToVector() * obj.material.kReflection);
}
if (obj.material.kTransmission > 0f)
{
bool outside = Extensions.Dot3(ray.direction, normal) > 0.0f;
var n1 = airKt;
var n2 = obj.material.kTransmission;
var norm = normal.Clone();
var refract = Extensions.Refract(ray.direction, norm, n1, n2).Normalize();
var rO = outside ? intersect + (normal * 0.001f) : intersect - (normal * 0.001f);
Ray r = new Ray(rO, refract);
SpawnRayKD(r, out var refractColor, depth + 1);
cVec += (refractColor.ToVector() * obj.material.kTransmission);
}
return(cVec);
}
public Shape3D TraceRay(Ray ray, out Vector intersect, out Vector normal)
{
Shape3D closestObj = null;
float? closestD = null;
intersect = null;
normal = null;
foreach (Shape3D obj in objects)
{
if (obj.Intersect(ray, out var i, out var n))
{
float dist = Math.Abs((ray.origin - i[0]).Length());
if (closestD == null || dist < closestD)
{
closestD = dist;
closestObj = obj;
intersect = i[0];
normal = n[0];
}
}
}
return(closestObj);
}
public bool SpawnRayKD(Ray ray, out Rgba32 color, int depth = 0)
{
if (depth > 4)
{
color = (ambientLight.ToVector() * ambientCoefficient).ToColor();//background;
return(false);
}
var cVec = Vector.Build.Dense(3);
Shape3D obj = TraceRayKD(ray, out var intersect, out var normal);
if (obj != null)
{
cVec += obj.material.Intersect(ray, intersect, normal, obj, true).ToVector();
cVec += ReflectAndRefractKD(obj, ray, intersect, normal, depth);
color = cVec.ToColor();
return(true);
}
else
{
color = (ambientLight.ToVector() * ambientCoefficient).ToColor();//background;
return(false);
}
}
//////
// Phong Illumination Model:
//
// L = ka * La <--- ambient
// + kd * [Li * Od * (Si . N)] <--- diffuse
// + ks * [Li * Os * (Ri . V) ^ ke)] <--- specular
//
// L - Final returned radiance (color value)
// ka - ambient coefficient
// La - world ambient radiance
// kd - diffuse coefficient
// ke - specular exponent
// [] - summation of all the light sources (i)
// Li - radiance of light i
// Si - angle of incidence of light i
// Ri - angle of reflectance of light i
// V - viewing angle
//////
public Rgba32 Illuminate(Ray ray, Vector isect, Vector normal, PhongMaterial material, Shape3D obj, bool KD = false)
{
// initialize Light (zeros)
Vector L = Vector.Build.Dense(3);
// add ambient lighting
Vector La = world.ambientLight.ToVector();
float ka = world.ambientCoefficient;
L += (La * ka);
// add up diffuse/specular/reflection lighting for each light
Vector Ld = Vector.Build.Dense(3);
Vector Ls = Vector.Build.Dense(3);
Vector Lr = Vector.Build.Dense(3);
// object/material diffuse/specular colors
Vector Od = material.diffuseColor.ToVector();
Vector Os = material.specularColor.ToVector();
// viewing direction
Vector V = -ray.direction.Normalize();
// shift intersection to avoid self-collision
Vector lIntersection = isect + (normal * 0.001f);
foreach (LightSource Li in world.GetLightSources())
{
// shadow ray
Vector Sdir = (Li.center - lIntersection).Normalize();
float l_d = Math.Abs((Li.center - lIntersection).Length());
Ray S = new Ray(lIntersection, Sdir);
// reflected ray
Vector Rdir = Extensions.Reflected(Sdir, normal).Normalize();
// Ray R = new Ray(lIntersection, Rdir);
// check for shadow ray -> other object intersection
bool shaded = false;
float shade = 0.0f;
if (KD)
{
var s_shape = world.TraceRayKD(S, out var i, out var n);
if (s_shape != null)
{
var s_d = Math.Abs((isect - i[0]).Length());
if (s_d < l_d)
{
shaded = true;
shade = 1.0f - Extensions.Clamp(s_shape.material.kTransmission, 0.0f, 1.0f);
}
}
}
else
{
foreach (Shape3D o_obj in world.objects)
{
if (!o_obj.Equals(obj))
{
if (o_obj.Intersect(S, out var I, out var N))
{
shaded = true;
shade = 1.0f - Extensions.Clamp(o_obj.material.kTransmission, 0.0f, 1.0f);
}
}
}
}
if (!shaded || shade < 1.0f)
{
// diffuse
Vector LiOd = Li.color.ToVector().Multiply(Od).Clamp(0.0f, 1.0f);
float dist = (float)Distance.Euclidean(Li.center, lIntersection);
float attenuation = Li.strength / (dist * dist);
// System.Console.WriteLine(attenuation);
LiOd *= attenuation;
float SdotN = Sdir.DotProduct(normal).Clamp(0.0f, 1.0f);
Ld += (SdotN * LiOd);
Ld -= shade;
Ld.Clamp(0.0f, 1.0f);
// specular
Vector LiOs = Li.color.ToVector().Multiply(Os).Clamp(0.0f, 1.0f);
LiOs *= attenuation;
float RdotV = ((float)Math.Pow(Rdir.DotProduct(V), material.specularExponent)).Clamp(0.0f, 1.0f);
Ls += (RdotV * LiOs);
Ls -= shade;
Ls.Clamp(0.0f, 1.0f);
}
}
Ld *= material.kDiffuse;
Ls *= material.kSpecular;
L += (Ld + Ls);
return(L.Clamp(0.0f, 1.0f).ToColor());
}
public override Rgba32 Intersect(Ray ray, Vector intersection, Vector normal, Shape3D obj, bool KD = false)
{
return(this.color);
}
public override Rgba32 Intersect(Ray ray, Vector <float> intersection, Vector <float> normal, Shape3D obj, bool KD = false)
{
return(GetMaterial(obj, intersection).Intersect(ray, intersection, normal, obj, KD));
}
public abstract Rgba32 Intersect(Ray ray, Vector intersection, Vector normal, Shape3D obj, bool KD = false);
public override Rgba32 Intersect(Ray ray, Vector intersection, Vector normal, Shape3D obj, bool KD = false)
{
return(lightingModel.Illuminate(ray, intersection, normal.Normalize(), this, obj, KD));
}
public void AddObject(Shape3D o)
{
o.objID = objects.Count;
objects.Add(o);
}