/** * Performs one line of sight calculation between the reference position and a specified grid * position. * * @param gridPosition the grid position. * @throws InterruptedException if the operation is interrupted. */ protected void performIntersection(Position gridPosition) throws InterruptedException { // Intersect the line between this grid point and the selected position. Intersection[] intersections = this.terrain.intersect(this.referencePosition, gridPosition); if (intersections == null || intersections.length == 0) { // No intersection, so the line goes from the center to the grid point. this.sightLines.add(new Position[] {this.referencePosition, gridPosition}); return; } // Only the first intersection is shown. Vec4 iPoint = intersections[0].getIntersectionPoint(); Vec4 gPoint = terrain.getSurfacePoint( gridPosition.getLatitude(), gridPosition.getLongitude(), gridPosition.getAltitude()); // Check to see whether the intersection is beyond the grid point. if (iPoint.distanceTo3(this.referencePoint) >= gPoint.distanceTo3(this.referencePoint)) { // Intersection is beyond the grid point; the line goes from the center to the grid point. this.addSightLine(this.referencePosition, gridPosition); return; } // Compute the position corresponding to the intersection. Position iPosition = this.terrain.getGlobe().computePositionFromPoint(iPoint); // The sight line goes from the user-selected position to the intersection position. this.addSightLine(this.referencePosition, new Position(iPosition, 0)); // Keep track of the intersection positions. this.addIntersectionPosition(iPosition); this.updateProgress(); }
protected boolean areShapesIntersecting(Airspace a1, Airspace a2) { if ((a1 instanceof SphereAirspace) && (a2 instanceof SphereAirspace)) { SphereAirspace s1 = (SphereAirspace) a1; SphereAirspace s2 = (SphereAirspace) a2; LatLon location1 = s1.getLocation(); LatLon location2 = s2.getLocation(); double altitude1 = s1.getAltitudes()[0]; double altitude2 = s2.getAltitudes()[0]; boolean terrainConforming1 = s1.isTerrainConforming()[0]; boolean terrainConforming2 = s2.isTerrainConforming()[0]; // We have to compute the 3D coordinates of the sphere's center ourselves here. Vec4 p1 = terrainConforming1 ? this.getSurfacePoint(location1, altitude1) : this.getPoint(location1, altitude1); Vec4 p2 = terrainConforming2 ? this.getSurfacePoint(location2, altitude2) : this.getPoint(location2, altitude2); double r1 = s1.getRadius(); double r2 = s2.getRadius(); double d = p1.distanceTo3(p2); return d <= (r1 + r2); } return false; }