SciVisFall2008/Assignment 0

Problem 1: query by tag, execute, annotate, query by example and prune history

To make sure you know how to search versions in the history tree of Vistrails do the following simple task:

1) In the History view locate the version tagged "EX1". Execute this version and annotate it with the name that appears in the visualization.

2) Query by Example Delaunay

Problem 2: pipeline from an image

From the root version on the history tree design a pipeline to reproduce the image below.

Tag the version with the resulting pipeline with label "Problem 2".

Problem 3: pipeline from C++ code

Starting from the root version on the history tree design a pipeline that is equivalent to the C++ source contQuad.cxx.

Tag the version of the resulting pipeline with label "Problem 3".

Problem 4: parameter exploration

Find the version tagged "spx" in the history tree. Execute this version and play with the resulting visualization.

The goal is to generate several isosurfaces of this model using the parameter exploration feature of Vistrails. But first a modification in the "spx" pipeline is ncessary to be able to extract a single isosurface of the model. Here are the steps: (1) modify the "spx" pipeline by inserting a "vtkContourFilter" in the middle of the connection from "vtkUnstructuredGridReader" to "vtkDataSetMapper" and (2) select the new "vtkContourFilter" and use the "SetValue" method with parameters 0 (Integer) and 0.5 (Float).

The steps are: , but first let's To extract the isosurface of value 0.5 of this model do (1) modify the "spx" pipeline by inserting a "vtkContourFilter" in the middle of the connection from "vtkUnstructuredGridReader" to "vtkDataSetMapper" and (2) select the new "vtkContourFilter" module and call the "SetValue" method with parameters 0 (Integer) and 0.5 (Float). Now you can execute the new pipeline and you should see a green isosurface.

With the final

module in the right place and

Starting with the isosurface figure that you generated in Problem 1, you will perform a parameter exploration to study the range of isosurfaces for this dataset. After selecting the "Problem 1" version, you can go into parameter exploration mode. To explore the isosurface values, you can drag the "SetValue(0, 0.3)" text into the parameter exploration canvas. You should do an exploration in the range of 0.0 to 1.0 in 6 steps, in the x-axis. At this point, the spreadsheet should be populated with a number of vistrails. Identify the "blue" one, and add it to the version tree. This can be done by going into the "View" menu on the spreadsheet, and clicking on the "Create Version" icon in the spreadsheet cell showing the blue isosurface. The history tree should have a new node that you should tag "Problem 2". (You can change the spreadsheet back to interactive mode by using the "View" menu again.)