Example #1
0
        public void getUV(V3 P, out float u, out float v)
        {
            V3 AB = B - A;
            V3 AC = C - A;

            V3 AP = P - A;

            //alfa
            u = V3.prod_scal(ref AP, ref AB) / AB.Norme2();
            //beta
            V3 aux = AP - u * AB;

            v = V3.prod_scal(ref aux, ref AC) / AC.Norme2();
        }
Example #2
0
        public bool intersection_RayObject(V3 R0, V3 Rd, out V3 P, out V3 N, out float t)
        {
            V3    CR0;
            float A, B, C, delta, t1, t2;

            P = new V3(0, 0, 0);
            N = new V3(0, 0, 0);
            t = -1;

            CR0 = R0 - Center;

            // (t^2) rd^2 + 2*t*rd*b +b^2 = R^2
            A = Rd.Norme2();
            B = 2f * V3.prod_scal(ref Rd, ref CR0);
            C = CR0.Norme2() - (R * R);

            delta = (B * B) - (4 * A * C);
            if (delta < 0)
            {
                return(false);
            }

            t1 = (-B + (float)Math.Sqrt(delta)) / (2 * A);
            t2 = (-B - (float)Math.Sqrt(delta)) / (2 * A);
            t  = (t1 > 0 && t1 < t2) ? t1 : t2;
            if (t < MIN_DISTANCE)
            {
                return(false);
            }

            P = R0 + t * Rd;
            N = getPixelSphereNormal(P);


            return(true);
        }
Example #3
0
        public override bool testColition(V3 positionStart, V3 direction, out double TPositionColition)
        {
            // need aproximation to calculate float
            // calculate the aproximation

            double a;
            double b;
            double c;

            a = (direction.Norme2());


            b = 2 * direction * (positionStart - this.getPosition());

            c = (positionStart - this.getPosition()).Norme2() - (this.rayon * this.rayon);


            // calcul alpha  = B²-4ac
            double alpha = (b * b) - (4 * a * c);



            // 0 result no colition alpha = 0
            if (alpha < 0)
            {
                TPositionColition = 0;
                return(false);
            }

            // 1 colition tangante
            if (alpha == 0)
            {
                TPositionColition = (-b) / (2 * a);
                return(true);
            }

            // 2 colition
            if (alpha > 0)
            {
                //Console.WriteLine("alpha");
                double t2 = (-b + Math.Sqrt(alpha)) / (2 * a);
                double t1 = (-b - Math.Sqrt(alpha)) / (2 * a);

                if (0 < t1 && t1 < t2)
                {
                    TPositionColition = t1;
                    return(true);
                }

                if (t1 < 0 && 0 < t2)
                {
                    TPositionColition = t2;
                    return(true);
                }

                if (t1 < 0 && t2 < 0)
                {
                    TPositionColition = 0;
                    return(false);
                }
            }

            TPositionColition = 0;
            return(false);
        }
Example #4
0
 public override float getIntersect(V3 R, V3 cam)
 {
     float t, t1, t2;
     float A = R.Norme2();
     float B = 2*(R.x * (cam.x - origin.x) + R.y * (cam.y - origin.y) + R.z * (cam.z - origin.z));
     float C = (cam.x - origin.x) * (cam.x - origin.x) + (cam.y - origin.y) * (cam.y - origin.y) + (cam.z - origin.z) * (cam.z - origin.z) - (this.rayon * this.rayon);
     float D = B * B - 4 * A * C;
     if (D < 0)
     {
         return -1f;
     }
     else
     {
         t = -1f;
         if (D > 0)
         {
             t1 = (-B - IMA.Sqrtf(D)) / (2 * A);
             t2 = (-B + IMA.Sqrtf(D)) / (2 * A);
             if (t1 < t2 && t1 >= 0)
             {
                 t = t1;
             }
             else if (t2 < t1 && t2 >= 0)
             {
                 t = t2;
             }
         }
         else
         {
             t = -B / (2 * A);
         }
         return t;
     }
 }