In this video we will demonstrate how to use of the Contour Details dialog in Tecplot 360.
Contour plots can show the variation of one variable across your dataset. To add a contour layer to your plot, toggle-on Contour in the Plot sidebar. Note that contours can only be plotted with organized data with a grid, such as IJ-ordered, IJK-ordered, or Finite element-data.
Adjusting the Contour
The current variable, longitude, isn’t very interesting compared to some of the other variables in this FVCOM dataset of Massachusetts bay. To adjust the contour, click the Contour Details button . This opens the Contour and Multi-Coloring Details dialog. You can change the variable from the dropdown menu at the top of the dialog. When I choose salinity, the plot will update.
Tecplot 360 will automatically assign the contour levels based on the variable range in your dataset. You can add new contour levels at specific values by entering them in the Add Level field, or you can reset all levels by clicking Set Levels… and entering the minimum, maximum, and specified distribution in the Enter Contour Levels dialog.
Adjusting the Color Map
You can adjust the current color map, or choose a different one from the dropdown menu in the center of the dialog. For this plot, we want a sequential color map, such as the default Viridis color map or one of the cmocean color maps. These color maps are perceptually linear; that is, there is a linear increase of luminosity across the scale. Many of the cmocean color maps will be useful for this dataset, but I will select the haline color map to match the salinity variable on the plot.
You can also load your own color map or export the existing color maps in Tecplot 360 by clicking on the gear icon. See our Knowledge Base article for step-by-step instructions on importing your own color maps, Setting Customer Color Maps as Defaults.
If I wanted to cut off my contour above or below a specified value, I could also do that with the Color cutoff toggles. There are other options for fine tuning your color map, like changing the distribution method and reversing the direction.
Updating the Contour Legend
Next, I will select the Legend tab to make some adjustments. This tab can also be opened by double-clicking on the contour legend in the plot. First, you can see the legend is too tall with all the additional contour levels. Simply toggle Resize automatically to scale down the height of the legend. You can change the legend Alignment from vertical to horizontal, add custom header text, alter font size and type, or change the text color. See this Knowledge Base article, Changing a Contour Legend Variable Name.
If I zoom out to get a better picture of the surface, the contour legend is difficult to see because of the geo-referenced image behind it. Correct this by selecting the Legend Box and toggling on Fill to add a white background.
Defining the Contour Variable Groups
The contour variable groups defined by this dialog are also used by a number of other features.
For example, in the Zone Style dialog, a number of features allow you to color by a contour group. The Contour tab is the most obvious, and it controls the type of contouring and the contour group used. Other zone layers, such as the Mesh, Vector, and Scatter tabs can take advantage of the contour groups. For example, I can change the color of the mesh of the plot to any of the defined Contour groups from this Color Chooser dialog by selecting one of the Multi numbers at the bottom, or by using the right-click context menu on the plot itself.
The definition of isosurfaces is a lesser-known connection with the Contour Details dialog. Each isosurface can be defined by a contour group variable. In the Isosurface Details dialog, clicking on the gear icon will open the Contour Details dialog, where you can set a contour group variable to use for the isosurface.
This concludes the tutorial on using the Contour details dialog. More information can be found in the User’s Manual. Thank you for watching.