#1479 Be more robust when passed invalid value

src/calc.cc

@@ -26,6 +26,7 @@
 
 #include "calc.h"
 #include "grid.h"
+#include <boost/math/special_functions/fpclassify.hpp>
 
 /*!
 	Returns the number of subdivision of a whole circle, given radius and
@@ -33,7 +34,9 @@
 */
 int Calc::get_fragments_from_r(double r, double fn, double fs, double fa)
 {
-	if (r < GRID_FINE) return 3;
+	// FIXME: It would be better to refuse to create an object. Let's do more strict error handling
+	// in future versions of OpenSCAD
+	if (r < GRID_FINE || boost::math::isinf(fn) || boost::math::isnan(fn)) return 3;
 	if (fn > 0.0) return (int)(fn >= 3 ? fn : 3);
 	return (int)ceil(fmax(fmin(360.0 / fa, r*2*M_PI / fs), 5));
 }

testdata/scad/3D/features/primitive-inf-tests.scad

@@ -7,3 +7,6 @@ sphere(1/0);
 polygon([[0,0,0],[1,0,0],[1,1/0,0]]);
 polyhedron(points = [[1/0,0,0],[-1,0,0],[0,1,0],[0,-1,0],[0,0,1],[0,0,-1]],
     triangles = [[0,4,2],[0,2,5],[0,3,4],[0,5,3],[1,2,4],[1,5,2],[1,4,3], [1,3,5]]);
+
+cylinder($fn=1/0);
+sphere($fn=1/0);

tests/regression/dumptest/primitive-inf-tests-expected.csg

@@ -7,4 +7,6 @@ group() {
 	sphere($fn = 0, $fa = 12, $fs = 2, r = inf);
 	polygon(points = [[0, 0, 0], [1, 0, 0], [1, inf, 0]], paths = undef, convexity = 1);
 	polyhedron(points = [[inf, 0, 0], [-1, 0, 0], [0, 1, 0], [0, -1, 0], [0, 0, 1], [0, 0, -1]], faces = [[0, 4, 2], [0, 2, 5], [0, 3, 4], [0, 5, 3], [1, 2, 4], [1, 5, 2], [1, 4, 3], [1, 3, 5]], convexity = 1);
+	cylinder($fn = inf, $fa = 12, $fs = 2, h = 1, r1 = 1, r2 = 1, center = false);
+	sphere($fn = inf, $fa = 12, $fs = 2, r = 1);
 }