Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve
(definition on Wikipedia).

noFill();
bezier(85, 20, 10, 10, 90, 90, 15, 80);
/*
 bezier(x1, y1, x2, y2, x3, y3, x4, y4)
 Can also be drawn in 3D.
 bezier(x1, y1, z1, x2, y2, z2, x3, y3, z3, x4, y4, z4)
*/