ParaView Contours and Isosurfaces
To generate either isolines or isosurfaces, ParaView uses the Contour Filter.
- First the user selects the data they wish to operate on from the Selection Window. It will be highlighted when this occurs.
- The user can then select Filter->Alphabetical->Contour from the main menu, or click on the Contour button. This will open the contour filter interface.
- The Contour By dropdown can be used to select the scalar field you want to extract your isosurface from. Only single-component scalar fields are available. To extract an isosurface from a single component of a vector field (e.g., the X component of Velocity) you will need to first use an Array Calculator to extract that component.
- Compute Normals - This is checked by default. This will generate 3-dimensional normal vectors at each point.
- Compute Gradients - This is not usually checked. This will compute a 3-dimentional gradient vector at each point from the selected field.
- Compute Scalars - This is not usually checked. Usually the selected scalar field will "disappear" from the resulting data set, as it should be only a single value (the isovalue selected). When working with multiple isovalues, like the ones generated in the Generate Range of Values box, it can be beneficial to keep these values around to color the different isosurfaces.
- The Value Range Section under Isosurfaces allows the user to input a new contour value. Simply input the value by using the New Value button. The value will now appear under the Value Range Section. Multiple contours can be generated in this way, or by using the New Range button. To remove a contour value, click the Delete button or Delete All button.
- The Scientific checkbox toggles on/off the display of scientific notation.
- The Apply button must be pressed before any contours will be generated.