Visualisation: default rendering configuration needs tuning for interactive plots (PyVista & Plotly)

[SLT2k]

Visualisation: default rendering configuration needs tuning for interactive plots (PyVista & Plotly)

While manually testing the new rendering with a geometry + vegetation case (campus STL, ~19k faces, 9000 vegetation points from veg.inp), several default rendering settings make the interactive output hard to read. None of these are functional bugs — the plots are correct but the configuration need tuning.

[SLT2k]

PyVista rendering configuration: four areas need tuning

Tested on fix/issue-322-pyvista-support with a geometry + vegetation case. All four issues below trace to hardcoded values in tools/python/udvis/scene.py and tools/python/udvis/udbase_vis.py.

1. Vegetation point cloud is not visible enough

plot_veg renders trees as size=2, opacity=0.2 green points (udbase_vis.py:321, hardcoded) — they barely visible comparing to the geometry edges.

2. Geometry outline/edge drawing is too heavy and mashed together

The overlay plots (plot_veg etc.) draws every mesh edge as a black wireframe (udbase_vis.py:271), so on fine meshes the buildings render as a near-solid black mass. Line weights are also inconsistent across sibling plots (width 2 in show_geometry/show_outline/plot_fac/plot_fac_type at :173/:248/:621/:768, but 1.5 in overlays and plot_independent_surfaces at :271/:666).

3. Rendering resolution — output sometimes too blurry

The plotter is created bare (pv.Plotter(), scene.py:439): default 1024×768 window and scale-1 screenshots. Upscaling at construction is not an option — image_scale > 1 during rendering makes VTK drop all add_point_labels text.

4. Axis labels clash; the hand-drawn axes need more testing

The PyVista axes are hand-drawn in _draw_pyvista_axes (scene.py:545-581) and show several rough edges: the z-axis title collides with the last y tick label at the shared origin corner (title/label offsets are fixed factors, :554/:568); tick count is fixed at 9 via linspace (:576) so labels come out as non-round numbers (e.g. "137"); the z-axis gets endpoint ticks only (:580); format %.0f and fonts are hardcoded (:560, :551, :571).