Absolute value ranges and line scaling at image export

Dear all,

I’ve been using ParaView for some years now, but there still are important issues that I never have been able to resolve. Now I’m writing a tutorial about my workflow in ParaView, and before publishing it I need to know if there is really no solution for it in ParaView, or if I’m missing important things.

  1. Is it possible to use absolute value ranges? When I load a 3D model (e.g., .obj) into ParaView, and apply the “Elevation” filter, the “Color scale” will only be relative, from 0 to 1. However, the model has an actual absolute scale (in meters), which allow me to do measurements on the model. Is it possible to use the absolute scale of the model, so that my color scale goes from, e.g., 0 to 2 m?

  2. Related to the first question: Is it possible to have absolute contour lines (i.e., contours separated by, e.g., 0.1 m)? Right now, I can only do relative contours (e.g., a fixed number of 20 contours which are then evenly spread over the whole z range).

  3. Some elements, most importantly the axis grid (which can be activated in the Properties pane) and contour lines (from the Contour filter), do not scale with the resolution I enter in the “Save Screenshot” tool during image export. Instead, the lines and fonts stay at a fixed pixel size, and get (on the exported high-res images) incredibly small or nearly invisible. The color scale, on the other hand, scales perfectly including its fonts. The option “Scale fonts proportionally” has no effect for this problem. I know that at least for the contour lines it is possible to increase “line width” in the properties pane of the Contour filter. But if I increase line width too much (>5) there are severe rendering issues, as the individual points of the contours appear star-shaped.

Any comments/hints would be greatly appreciated!
Thank you very much!

Welcome the the community ptarmigan!

I believe the answer is "no) for the first two questions. I will leave this to anyone else that knows better.

With regards to 3), File/ Save Screenshot/ Choose your file name/ OK/ Advanced (the little gear, right of the search box)/ Font Scaling/ Do Not Scale Fonts.

Thank you Walter!

Regarding 3), as said, the “Do Not Scale Fonts” option has no effect on the axis grid. Irrespective of which option is selected, the axis grid lines and fonts will always be the size at a given resolution. Is this a bug?

I know that, as a workaround, I can increase the font manually before exporting in the “Axis grid” settings, and with a bit of try and error I can figure out what font size is required at a given resolution (the fonts will then appear far too large on the screen but correct in the high-res export). However, I have not found a way to increase the line width of the axis grid.

Mind giving me really detailed instructions to see what you are seeing? Include what OS, and use a Source, Click this, then that, so I can replicate it? When I just did what I think you are doing, it looks fine to me… Think “Mom, I want
you to click that button there…”
:slight_smile: (Wait, I’m probably as old and cranky as your dad…)


Thanks again, and sure! I’m on Linux, ParaView 5.7.0 (always had the same issue with Windows too, though). I’m working with photogrammetric surface models of footprints, and I included a link to one example below, but it should be the same with any mesh. Here are the steps to reproduce:

  1. Download a 3D model of this dinosaur track to your Computer:

  2. Unpack the zip, navigate to folder “model”, and open the “paluxy_centrere.obj” in ParaView.

  3. Click “Apply” in the “Properties” pane to load the model.

  4. Scroll down in the “Properties” pane to the entry “Data Axes Grid”, and activate it. (Btw., I have no idea why the entry for the data axes grid appears twice in the Properties pane, the second time labelled as “Axes grid”. Which one you activate does not matter). A white axis grid will now appear on the screen surrounding the model. Note that the lines and labels are just large enough to read them properly.

  5. Apply “Filter” -> “Alphabetical” -> “Elevation”, set the line in the “Properties” pane to “Z Axis”, and click “apply”. A Color Scale will now appear, and the model will be nicely colored.

  6. Make sure to activate both entries in the “Pipeline browser” to have both the axis grid and the scale bar visible.

  7. Go to “File” -> “Save Screenshot”, choose *.png as file type and enter some file name; click “OK”.

  8. Increase the “Image Resolution” (Section “Size and Scaling”). For this, click on the little “x” icon and set the scale to “x 2x” to double the default values. Choose “x 2x” again, increasing it further. The resolution should now be four times as high as the default. Usually I go even higher when the problem will be even more severe.

  9. Click “OK” to export, and open the exported image in some Image Viewer. You will see that the Color Scale is of appropriate size, but that the “Axis grid” is so small that it is barely visible. The axis grid (both lines and fonts) will only be readable after zooming into the image (zoom setting of “100%”).