Bad constraints slow the system down - they always take the maximum number of iterations . Express face normals in terms of n independent variables. . Use a black-box optimisation routine to find the set of variables which minimises the objective function. . We might be trapped in a local minimum. . This method inherently slow as it makes no use of the geometric knowledge we already have .
Bad constraints slow the system down - they always take the maximum number of iterations .
Neither strategy is fully satisfactory . Both can be slow . Either method can be used if all else fails, but we want quicker methods for determining if constraints can be satisfied . Initially, all three relationships are possible, except that adjacent faces cannot be parallel . If the object is axis-aligned, no pair of faces may be at some other angle .