Added more tests for center(), and cut(). Added functions to access functionality (used to be in Perl interface).

src/test/libslic3r/test_trianglemesh.cpp

@@ -45,6 +45,14 @@ SCENARIO( "TriangleMesh: Basic mesh statistics") {
         THEN( "Number of normals is equal to the number of facets.") {
             REQUIRE(cube.normals().size() == facets.size());
         }
+
+        THEN( "center() returns the center of the object.") {
+            REQUIRE(cube.center() == Pointf3(10.0,10.0,10.0));
+        }
+
+        THEN( "Size of cube is (20,20,20)") {
+            REQUIRE(cube.size() == Pointf3(20,20,20));
+        }
     }
 }
 
@@ -81,12 +89,33 @@ SCENARIO( "TriangleMesh: Transformation functions affect mesh as expected.") {
             }
         }
 
-        WHEN( "The scaled cube is rotated 45 degrees.") {
+        WHEN( "The cube is rotated 45 degrees.") {
             cube.rotate(45.0, Slic3r::Point(20,20));
             THEN( "The X component of the size is sqrt(2)*20") {
                 REQUIRE(abs(cube.size().x - sqrt(2.0)*20) < 1e-2);
             }
         }
+
+        WHEN( "The cube is translated (5, 10, 0) units with a Pointf3 ") {
+            cube.translate(Pointf3(5.0, 10.0, 0.0));
+            THEN( "The first vertex is located at 25, 30, 0") {
+                REQUIRE(cube.vertices().at(0) == Pointf3(25.0, 30.0, 0.0));
+            }
+        }
+
+        WHEN( "The cube is translated (5, 10, 0) units with 3 doubles") {
+            cube.translate(5.0, 10.0, 0.0);
+            THEN( "The first vertex is located at 25, 30, 0") {
+                REQUIRE(cube.vertices().at(0) == Pointf3(25.0, 30.0, 0.0));
+            }
+        }
+        WHEN( "The cube is translated (5, 10, 0) units and then aligned to origin") {
+            cube.translate(5.0, 10.0, 0.0);
+            cube.align_to_origin();
+            THEN( "The third vertex is located at 0,0,0") {
+                REQUIRE(cube.vertices().at(2) == Pointf3(0.0, 0.0, 0.0));
+            }
+        }
     }
 }
 
@@ -94,6 +123,47 @@ SCENARIO( "TriangleMesh: split functionality.", "[!mayfail]") {
     REQUIRE(false); // TODO
 }
 
+SCENARIO( "TriangleMesh: slice behavior.", "[!mayfail]") {
+    REQUIRE(false); // TODO
+}
+
 SCENARIO( "make_xxx functions produce meshes.", "[!mayfail]") {
     REQUIRE(false); // TODO
 }
+
+SCENARIO( "TriangleMesh: Mesh merge functions", "[!mayfail]") {
+    REQUIRE(false); // TODO
+}
+
+SCENARIO( "TriangleMeshSlicer: Cut behavior.") {
+    GIVEN( "A 20mm cube with one corner on the origin") {
+        const Pointf3s vertices { Pointf3(20,20,0), Pointf3(20,0,0), Pointf3(0,0,0), Pointf3(0,20,0), Pointf3(20,20,20), Pointf3(0,20,20), Pointf3(0,0,20), Pointf3(20,0,20) };
+        const Point3s facets { Point3(0,1,2), Point3(0,2,3), Point3(4,5,6), Point3(4,6,7), Point3(0,4,7), Point3(0,7,1), Point3(1,7,6), Point3(1,6,2), Point3(2,6,5), Point3(2,5,3), Point3(4,0,3), Point3(4,3,5) };
+
+        auto cube {TriangleMesh(vertices, facets)};
+        cube.repair();
+        WHEN( "Object is cut at the bottom") {
+            TriangleMesh upper {};
+            TriangleMesh lower {};
+            cube.cut(Z, 0, &upper, &lower);
+            THEN("Upper mesh has all facets except those belonging to the slicing plane.") {
+                REQUIRE(upper.facets_count() == 12);
+            }
+            THEN("Lower mesh has no facets.") {
+                REQUIRE(lower.facets_count() == 0);
+            }
+        }
+        WHEN( "Object is cut at the center") {
+            TriangleMesh upper {};
+            TriangleMesh lower {};
+            cube.cut(Z, 10, &upper, &lower);
+            THEN("Upper mesh has 2 external horizontal facets, 3 facets on each side, and 6 facets on the triangulated side (2 + 12 + 6).") {
+                REQUIRE(upper.facets_count() == 2+12+6);
+            }
+            THEN("Lower mesh has 2 external horizontal facets, 3 facets on each side, and 6 facets on the triangulated side (2 + 12 + 6).") {
+                REQUIRE(lower.facets_count() == 2+12+6);
+            }
+        }
+    }
+
+}

xs/src/libslic3r/TriangleMesh.cpp

@@ -332,6 +332,14 @@ void TriangleMesh::translate(float x, float y, float z)
     stl_invalidate_shared_vertices(&this->stl);
 }
 
+void TriangleMesh::translate(Pointf3 vec) {
+    this->translate(
+        static_cast<float>(vec.x),
+        static_cast<float>(vec.y),
+        static_cast<float>(vec.z)
+    );
+}
+
 void TriangleMesh::rotate(float angle, const Axis &axis)
 {
     // admesh uses degrees
@@ -419,6 +427,11 @@ void TriangleMesh::rotate(double angle, const Point& center)
     this->translate(+center.x, +center.y, 0);
 }
 
+Pointf3
+TriangleMesh::center() const {
+    return this->bounding_box().center();
+}
+
 TriangleMeshPtrs
 TriangleMesh::split() const
 {
@@ -534,6 +547,23 @@ TriangleMesh::merge(const TriangleMesh &mesh)
     stl_get_size(&this->stl);
 }
 
+void TriangleMesh::cut(Axis axis, double z, TriangleMesh* upper, TriangleMesh* lower) 
+{
+    switch(axis) {
+        case X:
+            TriangleMeshSlicer<X>(this).cut(z, upper, lower);
+            break;
+        case Y:
+            TriangleMeshSlicer<Y>(this).cut(z, upper, lower);
+            break;
+        case Z:
+            TriangleMeshSlicer<Z>(this).cut(z, upper, lower);
+            break;
+        default: 
+            Slic3r::Log::error("TriangleMesh", "Invalid Axis supplied to cut()");
+    }
+}
+
 /* this will return scaled ExPolygons */
 ExPolygons
 TriangleMesh::horizontal_projection() const

xs/src/libslic3r/TriangleMesh.hpp

@@ -36,7 +36,14 @@ class TriangleMesh
     void WriteOBJFile(const std::string &output_file);
     void scale(float factor);
     void scale(const Pointf3 &versor);
+
+    /// Translate the mesh to a new location.
     void translate(float x, float y, float z);
+
+    /// Translate the mesh to a new location.
+    void translate(Pointf3 vec);
+
+
     void rotate(float angle, const Axis &axis);
     void rotate_x(float angle);
     void rotate_y(float angle);
@@ -76,6 +83,12 @@ class TriangleMesh
 
     /// Return the size of the mesh in coordinates.
     Pointf3 size() const;
+
+    /// Return the center of the related bounding box.
+    Pointf3 center() const;
+
+    /// Perform a cut of the mesh and put the output in upper and lower
+    void cut(Axis axis, double z, TriangleMesh* upper, TriangleMesh* lower);
 	
 	/// Generate a mesh representing a cube with dimensions (x, y, z), with one corner at (0,0,0).
     static TriangleMesh make_cube(double x, double y, double z);