/*
* Finds the area of the triangle formed by 3 vectors.
*/
public static double TriangleArea(Vect3 point1, Vect3 point2, Vect3 point3)
{
Vect3 triangleBase = (point1 - point2);
Vect3 side = (point1 - point3);
Vect3 height = side - side.ProjectOnVector(triangleBase);
return((triangleBase.Length() * height.Length()) / 2);
}
/*
* Fills VoxelGrid from component faces using a digital differential analyzer method.
*/
public void CreateShellFromFaces(Component component)
{
foreach (Face face in component.faces)
{
List <Vect3> trianglePoints = ConvertFaceToLocal(face, component);
Vect3 v1 = trianglePoints[0] / resolution;
Vect3 v2 = trianglePoints[1] / resolution;
Vect3 v3 = trianglePoints[2] / resolution;
// v2->v3 should be shortest triangle side
double v2v1length = (v2 - v1).Length();
double v3v2length = (v3 - v2).Length();
if (v3v2length > v2v1length)
{
Vect3 temp = v1;
v1 = v3;
v3 = temp;
}
double v3v1length = (v3 - v1).Length();
if (v3v2length > v3v1length)
{
Vect3 temp = v2;
v2 = v1;
v1 = temp;
}
Vect3 lp1 = v1;
Vect3 lp2 = v1;
Vect3 d2 = v2 - v1;
Vect3 d3 = v3 - v1;
double d2step = d2.Length();
double d3step = d3.Length();
double outerstep = d2step > d3step ? d2step : d3step;
outerstep *= 2;
d2 /= outerstep;
d3 /= outerstep;
int xi, yi, zi;
xi = Convert.ToInt32(lp1.x);
yi = Convert.ToInt32(lp1.y);
zi = Convert.ToInt32(lp1.z);
coordinateGrid[xi][yi][zi] = true;
lp1 += d2;
lp2 += d3;
int k = 0;
while (k <= outerstep)
{
Vect3 d = lp2 - lp1;
double step, x, y, z;
int i;
step = d.Length();
step *= 2;
if (step != 0)
{
d /= step;
}
x = lp1.x;
y = lp1.y;
z = lp1.z;
i = 0;
yi = Convert.ToInt32(y);
zi = Convert.ToInt32(z);
while (i <= step)
{
xi = Convert.ToInt32(x);
coordinateGrid[xi][yi][zi] = true;
yi = Convert.ToInt32(y);
coordinateGrid[xi][yi][zi] = true;
zi = Convert.ToInt32(z);
coordinateGrid[xi][yi][zi] = true;
x += d.x;
y += d.y;
z += d.z;
i += 1;
}
lp1 += d2;
lp2 += d3;
k += 1;
}
}
}
