parallel projection (2D rendering)

[laserman781]

Can I view the 2D plane as a parallel projection? I know this can be done in paraview so I assume it can also be done in pyvista.

[banesullivan]

This isn't currently implemented, but we can put it on the todo list!

[banesullivan]

@laserman781 - there is actually a pretty simple solution to this which I am about to implement. All you need to do is call .SetParallelProjection(True) on the active camera:

import pyvista as pv
from pyvista import examples
mesh = examples.download_st_helens().warp_by_scalar()

p = pv.Plotter(notebook=False)
p.add_mesh(mesh)
p.camera_position = 'xy'
p.camera.SetParallelProjection(True)
p.show()

I just implemented some helper methods to make this easier and also be able to toggle it with the BackgroundPlotter in e7ec9f0. The new methods are enable_parallel_projection() and disable_parallel_projection() which can be called from any plotter:

p = pv.Plotter(notebook=False)
p.add_mesh(mesh)
p.enable_parallel_projection()
p.show()

Or better yet, check out the menus in the BackgroundPlotter:

p = pv.BackgroundPlotter()
p.add_mesh(mesh)
p.show()

[banesullivan]

Also, you might be interested in the enable_image_style() function on the plotters which makes the rendering truly 2D with parallel projection:

import pyvista as pv
from pyvista import examples

# This is a 2D image on the XY plane
mesh = examples.download_st_helens()

p = pv.Plotter(notebook=False)
p.add_mesh(mesh)
p.enable_parallel_projection()
p.enable_image_style()
p.view_xy()
p.show()