Selection in Para View Utkarsh Ayachit Kitware Inc

Selection in Para. View Utkarsh Ayachit Kitware Inc.

Selection • Mechanism to identify subset of a dataset • Focus on selected subset • Inspect properties of the subset • Further process subset alone • Track subset over time

Focus on subset

Track subset over time

Selection in Para. View • What are we selecting? • Data produced by a source • Active Selection • One application wide selection • All views show the same selection if possible • Creating a new selection results in removing the old one • Transient: cannot be saved in state files, does not respect undo/redo.

Selection Components • Selection Inspector • Inspect the active selection • Spreadsheet View • Inspect the selected data

Active Selection Inspector • Accessible through View | Selection Inspector • Used to create/modify active selection • Shows the properties of the active selection • Control how the active selection is shown

Create new selection Active selection properties Selection type Selected cells ids Selection display Properties/Labeling

Spreadsheet View • Used to view the raw cell/point data • To create: split an existing view and select “Spreadsheet view” • Display tab provides option to view only selected items

What is shown in the view Show only selected items Attribute shown Select block to inspect

Selecting using 3 D View • Surface cells/points • Cells/Points within a frustum • Blocks in a composite dataset

Select Cells on surface • Used to select any set of visible cells on the surface of a dataset • Representation should be points / wireframe / surface with edges • With 3 D view active, use the ‘Select Cells On’ tool button (shortcut ‘S’) to enter selection mode • Click and drag to select cells

Select Points on surface • Same as selecting cells on surface except use ‘Select Points On’ tool button.

Selection Linking • Selection is linked among all views (whenever possible) • Active selection is shown in all view (whenever possible)

Select Cells Through • Select all cells intersecting a frustum • Use ‘Select Cells Through’ • Selection Inspector has a check button to show the selection frustum • Use ‘Select Points Through’ for selecting points

Select Blocks • Select blocks in a composite dataset

Composite Datasets • Composite datasets are datasets comprising of other datasets. • Group together assemblies: vtk. Multi. Block. Data. Set • Adaptive mesh refinement: vtk. Hierarchical. Box. Data. Set

Select Blocks • Use ‘Select Block’ (shortcut ‘B’) to select blocks in a composite dataset • Keep Ctrl pressed when clicking to add to existing selected blocks

Selecting using Spreadsheet View • Can create Point/Cell index based selections (depending on what attribute is being shown) • Click to select rows as one would in any spreadsheet application • Can use modifiers such as Ctrl, Shift while selecting • Selection is shown in all views

Selecting using Selection Inspector • Create new selections • Convert selections • id based to global id based • frustum to id based • Modify existing selection

Location based selection • Select cell enclosing the location or select point closet to the location within a threshold • Created using the Selection Inspector and changing the selection type to Locations • Provides widgets to specify locations

Threshold based selection • Select cells or points that have an attribute value within the specified range • Created using Selection Inspector

Labeling Selected Items • Label selected cells/points using Selection Inspector • Choose the array/id to label with

Extract Selection • Extract selected subset for further processing • Create ‘Extract Selection’ filter • Make selection and ‘Copy Active Selection’ • Hit ‘Apply’

Extract Selection • Once a selection is extracted it’s treated as a first class data source. • One can apply filters to it as usual. • Extracted selection get saved in state files.

Plot Selection over Time • Plot data variable changes over time for a set of cells or points • Use ‘Plot Selection Over Time’ filter • Make selection and ‘Copy Active Selection’ • Output can be shown on a XY plot

Plot Selection over Time • Changes for each cell/point selected can be plotted, one at a time, by choosing the block on the Display Tab

Conclusion • • • Selection provides mechanism to focus on a subset of the dataset Selection identifies the cells/points in the output of a filter/source Active selection is shown in all views (when applicable) Selection inspector can be used to create/modify the active selection Spreadsheet view can be used to explore the attribute values for the selected items • Extracting a selection makes it possible to further processes the selected subset