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[ScatterView] Check if Delaunay is actually necessary

Open vasole opened this issue 6 years ago • 7 comments

Close to regular grids would be better represented by quads than by triangles. Furthermore, the Delaunay triangulation would not be necessary.

vasole avatar Aug 08 '19 12:08 vasole

The above refers to the "Solid" visualization mode.

vasole avatar Aug 08 '19 12:08 vasole

In fact, it would be enough to replace the overlay by an image instead of a set of triangles.

vasole avatar Aug 09 '19 12:08 vasole

I am not sure i understand. The use case is not the same.

Or you expect a function smart enough to decide if your data is regular or not?

vallsv avatar Aug 09 '19 13:08 vallsv

I expect a function smart enough to decide if the data are regular or not.

vasole avatar Aug 09 '19 15:08 vasole

Checking that the data is a grid to avoid computing Delaunay triangulation should definitely be a good optimization... but that is not as replacing the visualization with an image with nearest interpolation, or that would lead to a different visualization.

I think we need more options to interpolate a scatter plot (issue #1910 already opened on that), and to me, what you're thinking of is a fast pass for nearest interpolation of scatter plot when it is a grid.

t20100 avatar Aug 26 '19 10:08 t20100

No, I am not thinking about a a fast pass for interpolation. I am just thinking at an alternative display mode. As said in the opening any other thing could come as a bonus but the correct thing would be to show the alternative display and use the actual data if interpolation is required.

vasole avatar Sep 12 '19 08:09 vasole

This is what I wanted to mean, I think we are saying the same thing.

There are different ways of doing it with small differences (e.g., image, voronoi, #2743, histogram with bin size chosen to have on point in each bin if the grid is really regular).

I'll make some demos of some of those. I'm fine providing many modes in the API, but I'd prefer to keep the number of options available from the GUI as small as possible. That being said, we need to add one for this case.

t20100 avatar Sep 13 '19 07:09 t20100