How do I get my screenspace widget to show up more consistently

Very good ideas, thank you! My issue with the draw location now is just due to the fact that its drawn at the location on a vertical line that is closest to the hit of a raytrace on the red outlines, which causes huge inaccuracy from angles that are closer to parallel to the vertical line, basically what I need to do is find a vector equation that, given lines A and B, finds point on line A that is closest to B.