Experimental test issue tracker

[henrikmidtiby]

The intention with this issue is to create an overview of the types of errors on the Experimental branch.

At the current state of the experimental branch (40c1661 2026-02-16), the types of errors on the pytest suite is as follows.

    196 GraphicalDeviationError
     23 AssertionError
     16 TypeError
      9 AttributeError
      8 NotImplementedError
      7 assert False
      3 Failed
      1 NameError
      1 _moderngl.Error
      1 FileNotFoundError
      1 Exception
      5 <not described>

The list was generated with the command:

cat experimental_errors.txt | grep FAILED | sed "s/FAILED \(.*\)::.* - \([^:]*\).*/\2/g" | sort | uniq -c | sort -nr

The dominating group of errors are the GraphicalDeviationErrors.
The errors in that group can be divided into the following groups.

• Larger surfaces differ due to differences in their fill (118 errors)
• Differences along edges of objects (67 errors)
• Differences in 3D viewpoint (8 errors)
• Variations in the rendered shape (5 errors)
• Unclassified (8 errors)

I have included a number of examples below.

Larger surfaces differ due to differences in their fill

Example with the test `tests/test_graphical_units/test_img_and_svg.py::test_Inheritance`

Differences along edges of objects

Example with the test `tests/test_graphical_units/test_geometry.py::test_AnnularSector`

Differences in 3D viewpoint

Example with the test tests/test_graphical_units/test_polyhedra.py::test_ConvexHull3D

Variations in the rendered shape

Example with the test tests/test_graphical_units/test_functions.py::test_ImplicitFunction