Selection Policy

This is a developing page that collects notes on the selection policy for ParaView3.

Adoption of existing standard

Ideally we would adopt a 'standard' selection policy (meaning what keystrokes, mouse movements, and modalities are used when doing selection in an application). But there seems to be no real 'standard' when it comes to selection within an application. Each application/domain has it's own approach and obviously some approaches work better than others. So, like the rebels we are, we're going to roll our own.

Desired Functionality

• Quick usage (in and out of selection mode should be very simple)
• Intuitive mode changes (obvious when you are in either move or select mode)
• All functionality available through 'quick keys'
• UI always properly reflects the current mode, even for quick transistions

Proposed Approach

In general the group seems to have consensus on the concept of "one-shot" selection, meaning I invoke the selection mode (either through UI or quick key) I make a selection and the mode is automatically switched back to the move mode.

• Take away: The default behavior of switching to selection will be "one-shot".

Less concensus was reached on how to do "extended" select, meaning I want to do a sequence of selection operations, additive selections, subtraction selections (shift-ctrl type of operations).

• Take away: Have three icons for mode: pick, select, and extended select. Extended select will change the mode to select and leave it in select. The shift and ctrl keys will behave as the windows file browser dialog selection behaves.

We also had some discussion about what the quick keys to invoke "one-shot" select was going to be. Upon reflection I do not like the 'P' key. Since most people are right handed you would like a left handed key to invoke and move the mouse with the right hand.

• Take away: We will use the 'S' key to invoke the one-shot select mode.