Pick atoms beneath density map surfaces

[olibclarke@…]

On May 25, 2017, at 6:24 AM, Oliver Clarke wrote:

Hi,

Often I want to select or hover over (to reveal tooltip info) atoms located under a transparent surface or mesh. It is much less common to want to select a volume with ctrl-click in my experience. Would it be possible to add a modifier (e.g. Shift or alt/option) for volume selection, and otherwise default to selection of/interaction with the atomic model(s)?

I feel like since ChimeraX deals mostly with these two data types, often in combination, having a clear way to distinguish interaction with them would be useful - it adds one extra step to be able to see atoms under a mesh, go to the volume viewer and turn of the required volume or volumes before selecting/identifying them - what do you think?

Cheers
Oli

[Tom Goddard]

There is a capability to make maps not pickable, so you can pick objects inside surface / mesh.

volume pickable false

This does not effect atomspec balloons, although perhaps it should. Also the maps are pickable by default and we don’t have preferences yet, so you can’t remember this setting between sessions.

Maybe in the future we can change default behavior. I’m not in favor of relying on modifier keys since 99% of users will not know about them. Any mechanism that prevents you from selecting a map will need some alternative to select the map and that creates complexity that makes the program hard to use. But of course in your use case with a refining a model in a map the current behavior is horrible. One partial fix is in some ticket (not implemented) is that it should pick between mesh lines. Still it would be better for you to never pick the map. Another partial fix is to pick the map if it is opaque, but not if it is transparent. With that you would possibly still want to pick the map if the click is on the map with no atom underneath.

[olibclarke@…]

One other idea for this is to change the selection hierarchy in a conditional manner, so that models take priority if and only if there is both a model displayed, and a map displayed with either mesh or transparency.

When I say "take priority", I mean that in this circumstance, Ctrl-clicking on an atom that is obscured by a map would select it, and hovering over it would display an atomspec balloon, but ctrl-clicking on the map anywhere that an atom is *not* underneath the pointer would select the map.

Cheers
Oli

[Tom Goddard]

I've made atom description popup windows when hovering the mouse ignore unpickable volumes (when "volume pickable false" used) and instead describe what would be selected at that mouse position.

[Tom Goddard]

About 6-12 months ago I made picking atoms through transparent volume surfaces and meshes work.