#
# The most common example of wireframe ambiguity. See for example:
# Geometric Modeling by Michael E. Mortenson, page 4...
#

save_res = resolution;
save_mat = view_mat;

view_mat = view_mat * scale(vector(0.6, 0.6, 0.6)) * rotx(30) * roty(20);

A = box(vector(-0.5, -0.5, -0.55), 1.0, 1.0, 1.1);

resolution = 4;			# To create 4 sided pyramids from cones...
C1 = cone(vector(0.0, 0.0, -0.6), vector(0.0, 0.0,  0.6001),
	  0.6 * sqrt(2.0), 1) *	rotz(45);
C2 = cone(vector(0.0, 0.0,  0.6), vector(0.0, 0.0, -0.6),
	  0.6 * sqrt(2.0), 1) * rotz(45);

A = A - C1 - C2;
free(C1);
free(C2);
view(list(view_mat, A), on);

B = box(vector(-0.3, -0.3, -1.0), 0.6, 0.6, 2.0);
C = A - B;
free(A);
free(B);

final = convex(C);
free(C);

beep();
interact(final);
save("ambiguit", final);

f1 = instance( "final", rx( 90 ) * tx( 2 ) );
f2 = instance( "final", ry( 90 ) * tx( -2 ) );

view_mat = scale(vector(0.3, 0.3, 0.3)) * rotx(40) * rotz(10) * roty(20);
interact(list(view_mat, final, f1, f2));
save("ambigui2", list(final, f1, f2));

free(f1);
free(f2);
free(final);

view_mat = save_mat;
resolution = save_res;