dont crash if there's infinity or NaN in transformation matrix

src/CGALEvaluator.cc

@@ -241,6 +241,15 @@ Response CGALEvaluator::visit(State &state, const TransformNode &node)
 			// First union all children
 			N = applyToChildren(node, CGE_UNION);
 
+			if ( matrix_contains_infinity( node.matrix ) ) {
+				PRINT("Warning: Transformation matrix contains Infinity - removing object.");
+				N.reset();
+			}
+			if ( matrix_contains_nan( node.matrix ) ) {
+				PRINT("Warning: Transformation matrix contains Not-a-Number - removing object");
+				N.reset();
+			}
+
 			// Then apply transform
 			// If there is no geometry under the transform, N will be empty and of dim 0,
 			// just just silently ignore such nodes
@@ -248,7 +257,7 @@ Response CGALEvaluator::visit(State &state, const TransformNode &node)
 				// Unfortunately CGAL provides no transform method for CGAL_Nef_polyhedron2
 				// objects. So we convert in to our internal 2d data format, transform it,
 				// tesselate it and create a new CGAL_Nef_polyhedron2 from it.. What a hack!
-				
+
 				Eigen::Matrix2f testmat;
 				testmat << node.matrix(0,0), node.matrix(0,1), node.matrix(1,0), node.matrix(1,1);
 				if (testmat.determinant() == 0) {

src/linalg.cc

@@ -1,4 +1,5 @@
 #include "linalg.h"
+#include <boost/math/special_functions/fpclassify.hpp>
 
 // FIXME: We can achieve better pruning by either:
 // o Recalculate the box based on the transformed object
@@ -25,3 +26,23 @@ BoundingBox operator*(const Transform3d &m, const BoundingBox &box)
 	return newbox;
 }
 
+bool matrix_contains_infinity( const Eigen::Transform3d &m )
+{
+  for (int i=0;i<m.matrix().rows();i++) {
+    for (int j=0;j<m.matrix().cols();j++) {
+      if ((boost::math::isinf)(m(i,j))) return true;
+    }
+  }
+	return false;
+}
+
+bool matrix_contains_nan( const Eigen::Transform3d &m )
+{
+  for (int i=0;i<m.matrix().rows();i++) {
+    for (int j=0;j<m.matrix().cols();j++) {
+      if ((boost::math::isnan)(m(i,j))) return true;
+    }
+  }
+	return false;
+}
+

src/linalg.h

@@ -14,6 +14,9 @@ using Eigen::Matrix3d;
 using Eigen::Matrix4d;
 using Eigen::Transform3d;
 
+bool matrix_contains_infinity( const Eigen::Transform3d &m );
+bool matrix_contains_nan( const Eigen::Transform3d &m );
+
 BoundingBox operator*(const Transform3d &m, const BoundingBox &box);
 
 class Color4f : public Eigen::Vector4f

testdata/scad/bugs/transform-nan-inf-tests.scad

@@ -0,0 +1,10 @@
+// Test translation by NaN and Infinity
+
+// NaN test - cube(2) should not be rendered
+cube(1);
+angle = asin(1.1);
+render()
+rotate([0, 0, angle])
+cube(2);
+
+// FIXME: how do you test infinity?