Roughly simulating gravitational effects in openscad, by request

gistfile1.txt

use <functional.scad>; // from https://github.com/thehans/FunctionalOpenSCAD

black_hole_center = [5,5,5];
black_hole_mass = 45*$t;

wallsize = [10,10];
stepsize = [0.5,0.5];
grid = gridPoints([wallsize.x,0.1], stepsize);
wall = linear_extrude(height=10, poly=grid, slices=wallsize.y/stepsize.y);
warpedWall = warpPoints(wall, black_hole_center, black_hole_mass);
//poly2d(grid);
poly3d(wall);
poly3d(warpedWall);

color([0,0,0]) translate(black_hole_center) sphere(0.1);

function gridPoints(size, stepsize, zoffset) = 
  let(
    xcount = ceil(size.x/stepsize.x)
  )
  [for(j = [0:1], i = [0:1:xcount]) [j ? stepsize.x*xcount - i*stepsize.x : i*stepsize.x, j*size.y] ];

function warpPoints(poly, center, mass) = 
  let(
    points = get_points(poly),
    newpoints = [for (point = points) 
      let(r = norm(point-center), G = min(1,mass/(r*r)) ) 
      point+(center-point)*G
    ]
  )
  [newpoints, poly[1]];