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You can often "simulate" recursion with partially-recursive code.

One trick is to "checkpoint" the results, so that you recurse in "chunks" and your stack never gets too big.

If you have pseudo-code you could post, we could possibly suggest some other tricks (there's others too)?

The checkpoint sounds well. Still I'm unsure how I could use it with my problem, but I'll think about it... :-)

The task is to find for a 3d modell all adjacent polygons with a soft angle (between their normal vectors) and setting them to the same smooth-group. The pseudo code looks like this:

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| main { List polygonlist; int current_smoothgroup_number; for (each polygon in polygonlist) { if (polygon's smoothgroup_number isn't set) { set polygon's smoothgroup_number to current_smoothgroup_number; call find_neighbours(polygon); current_smoothgroup_number++; } } }
find_neighbours(polygon) { get all neighbour polygons; for (each neighbour_polygon) { if ( neighbour_polygon's smoothgroup_number isn't set && angle of normal vectors between polygon and neighbour_polygon < crease_angle) { set neighbour_polygon's smoothgroup_number to current_smoothgroup_number; call find_neighbours(neighbour_polygon); } } } |

Now imagine a sphere with several thousands polygons which all have soft edges...