Feels nice to have this functionality now. The code is ugly. Maybe even a do over. I see what you mean about line picking. Even with the thickened back buffer line size, It's a little wonky. Forgive my stubborn Thank you for the interaction. I can see now how zone management would feel better.
I do read the one pixel under the cursor directly but I'm using that back buffer twice per frame. Once to render the gizmo with a much thicker line width (6.0) pick from that. Clear and render the scene and thin lines (1.0) and present that.. yeah, requires a flush...didn't see a reliable way around it.
I thought about ray casting or similar but for me the better path is to keep my head on the shader side. My goal is to see how far I can push it in that space...I have some post process (or I guess it's called deferred) hopes and dreams for the point lights
humble attempt in the current source branch.
@MarkK. The picking video looks nice.
Are you directly reading color in buffer under given pixels for gizmo? Or using a different trick?
I'm quite curious as I remember using the same, but other people who worked with engine were complaining that hitting specific pixel is too hard (I've switched to analytical model where I calculate distance against line/circle and select the correct one - and it tends to feel a bit better).