// compute incircle of triangle A, B, C
@Override
public void compute() {
// bisector of angle ABC
double dAB = getA().distance(getB());
double dAC = getA().distance(getC());
double dBC = getB().distance(getC());
double dmax = dAB > dBC ? dAB : dBC;
A1.setCoords(
dmax / dAB * (getA().inhomX - getB().inhomX) + getB().inhomX,
dmax / dAB * (getA().inhomY - getB().inhomY) + getB().inhomY,
1.0d);
C1.setCoords(
dmax / dBC * (getC().inhomX - getB().inhomX) + getB().inhomX,
dmax / dBC * (getC().inhomY - getB().inhomY) + getB().inhomY,
1.0d);
B1.setCoords((A1.inhomX + C1.inhomX) / 2.0d, (A1.inhomY + C1.inhomY) / 2.0d, 1.0d);
GeoVec3D.lineThroughPoints(getB(), B1, bisectorB);
// bisector of angle BCA
dmax = dAC > dBC ? dAC : dBC;
A1.setCoords(
dmax / dAC * (getA().inhomX - getC().inhomX) + getC().inhomX,
dmax / dAC * (getA().inhomY - getC().inhomY) + getC().inhomY,
1.0d);
B1.setCoords(
dmax / dBC * (getB().inhomX - getC().inhomX) + getC().inhomX,
dmax / dBC * (getB().inhomY - getC().inhomY) + getC().inhomY,
1.0d);
C1.setCoords((A1.inhomX + B1.inhomX) / 2.0d, (A1.inhomY + B1.inhomY) / 2.0d, 1.0d);
GeoVec3D.lineThroughPoints(getC(), C1, bisectorC);
// intersect angle bisectors to get incenter
GeoVec3D.lineThroughPoints(getB(), getC(), sideBC);
GeoVec3D.cross(bisectorB, bisectorC, incenter);
GeoVec3D.cross(incenter, sideBC.x, sideBC.y, 0.0, heightBC);
GeoVec3D.cross(sideBC, heightBC, heightFoot);
double dist = incenter.distance(heightFoot);
circle.setCircle(incenter, dist);
}