import grid3; size(10cm,0,IgnoreAspect); currentprojection=orthographic(0.25, 1, 0.25); limits((-2,-2,0),(0,2,2)); grid3(new grid3routines [] {XYXgrid(-0.5), XYXgrid(1.5)}, pGrid=new pen[] {red, blue}, pgrid=new pen[] {0.5red, 0.5blue}); xaxis3(Label("$x$",position=EndPoint,align=Z), YZEquals(-2,0,extend=false), RightTicks3()); yaxis3(Label("$y$",position=EndPoint,align=Z), XZEquals(-2,0), RightTicks3()); zaxis3(Label("$z$",position=EndPoint,align=X), XYEquals(-2,-2), RightTicks3(Label("",align=-X-Y)));