csg_surface.cpp

This example generates the detail for the further 3D printing using the surface mode. The CSG principles demonstrated.

// This example generates the detail for the further 3D printing using the surface mode. The CSG principles demonstrated.
#include <CoreAPI.h>
//@config: Debug
using namespace coat;
 
// The general problem of surface mode - boolean operations are less stable that in voxels.
// So you need to avoid booleans of objects with identical planes intersections.
EXPORT
int main() {
    // create new volume, don't need to set density as in voxels
    auto current = Scene::sculptRoot().addChild("Detail");
    // get the volume object to refer later
    auto volume = current.Volume();
    // turn to surface mode
    volume.toSurface();
    // set the details level for the more consistent polygons density
    prim::push_details(3);
    // add the sphere, diameter 16, dense (30 divisions)
    sphere().diameter(16).details(30).add(volume);
    // the cylinder that will be use to clip the top and bottom of the figure
    cylinder clip;
    clip.height(10).diameter(20);
    //move down 9mm and subtract. We move 9mm (not 10) to avoid planes exact intersection,
    //because exact intersection is problematic for the surface mode. 
    clip.y(-9).subtract(volume);
    //move up 9mm (back) and additionally 7 mm up and subtract
    clip.y(9 + 7).subtract(volume);
    // add the base of the figure. pay attention, we create temporary object using the cylinder() and operate,
    // this is a bit different from the clip object that we used twice
    cylinder().height(1.25).diameterBottom(19.0).diameterTop(18.5).add(volume);
    // make hole at the top
    cylinder().height(8).diameter(6).y(4).subtract(volume);
    // make hole through all the object
    cylinder().height(8).diameter(3).y(-2).subtract(volume);
    // no need to relax at the end because the surface is clean
    return 0;
}