getRimPointsIndices.m
1145767ab72dmaster

getRimPointsIndices.m
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			function output = getRimPointsIndices(obj)
			% Return the indices of the points on the rim of the glenoid surface.
			% To find the rim points, this function analyses the faces of the glenoid.surface
			% structure. These faces are triangles, each triangle is defined by three points
			% of the glenoid's surface. The points on the rim are defined to be the points
			% that appear in the faces 4 times or less (usually 3 or 4 times). Consequently,
			% the other points that appear more than 4 times in the faces (usually 5 or 6
			% times) are expected to be the inner points of the surface.
			%
			% WARNING: This is an empirical method to define which points are the rim points.
			% It is not based on the glenoid's surface tesselation algorithm and might
			% return false positive and false negative points.
			% For example, P200 shoulderAuto rim points found with the current function
			% feature several 4-occurence points that are inner points of the surface. There
			% are also 5-occurence rim points that are not detected.
			% Fix hint to try: Run a new triangulation algorithm on the glenoid points (
			% like the matlab's delaunay() funtion).

			trianglePointsIndices = obj.surface.faces;
			pointsOccurence = arrayfun(@(pointIndex)sum(trianglePointsIndices == pointIndex,"all"),...
			unique(trianglePointsIndices));
			rimPointsIndices = find(pointsOccurence <= 4);
			output = rimPointsIndices;
			end