Point3i locatePixel(Point3f ptXyz) {
		pointVector.set(ptXyz);
		xyzToPixelVector(pointVector);
		ptiTemp.x = (int) (pointVector.x + 0.5f);
		// NOTE: fails if negative -- (int) (-0.9 + 0.5) = (int) (-0.4) = 0
		ptiTemp.y = (int) (pointVector.y + 0.5f);
		return ptiTemp;
	}