Exemplo n.º 1
0
void
SLAPrint::slice()
{
    TriangleMesh mesh = this->model->mesh();
    mesh.repair();
    
    // align to origin taking raft into account
    this->bb = mesh.bounding_box();
    if (this->config.raft_layers > 0) {
        this->bb.min.x -= this->config.raft_offset.value;
        this->bb.min.y -= this->config.raft_offset.value;
        this->bb.max.x += this->config.raft_offset.value;
        this->bb.max.y += this->config.raft_offset.value;
    }
    mesh.translate(0, 0, -bb.min.z);
    this->bb.translate(0, 0, -bb.min.z);
    
    // if we are generating a raft, first_layer_height will not affect mesh slicing
    const float lh       = this->config.layer_height.value;
    const float first_lh = this->config.first_layer_height.value;
    
    // generate the list of Z coordinates for mesh slicing
    // (we slice each layer at half of its thickness)
    this->layers.clear();
    {
        const float first_slice_lh = (this->config.raft_layers > 0) ? lh : first_lh;
        this->layers.push_back(Layer(first_slice_lh/2, first_slice_lh));
    }
    while (this->layers.back().print_z + lh/2 <= mesh.stl.stats.max.z) {
        this->layers.push_back(Layer(this->layers.back().print_z + lh/2, this->layers.back().print_z + lh));
    }
    
    // perform slicing and generate layers
    {
        std::vector<float> slice_z;
        for (size_t i = 0; i < this->layers.size(); ++i)
            slice_z.push_back(this->layers[i].slice_z);
        
        std::vector<ExPolygons> slices;
        TriangleMeshSlicer(&mesh).slice(slice_z, &slices);
        
        for (size_t i = 0; i < slices.size(); ++i)
            this->layers[i].slices.expolygons = slices[i];
    }
    
    // generate infill
    if (this->config.fill_density < 100) {
        std::auto_ptr<Fill> fill(Fill::new_from_type(this->config.fill_pattern.value));
        fill->bounding_box.merge(Point::new_scale(bb.min.x, bb.min.y));
        fill->bounding_box.merge(Point::new_scale(bb.max.x, bb.max.y));
        fill->spacing       = this->config.get_abs_value("infill_extrusion_width", this->config.layer_height.value);
        fill->angle         = Geometry::deg2rad(this->config.fill_angle.value);
        fill->density       = this->config.fill_density.value/100;
        
        parallelize<size_t>(
            0,
            this->layers.size()-1,
            boost::bind(&SLAPrint::_infill_layer, this, _1, fill.get()),
            this->config.threads.value
        );
    }
    
    // generate support material
    this->sm_pillars.clear();
    ExPolygons overhangs;
    if (this->config.support_material) {
        // flatten and merge all the overhangs
        {
            Polygons pp;
            for (std::vector<Layer>::const_iterator it = this->layers.begin()+1; it != this->layers.end(); ++it)
                pp += diff(it->slices, (it - 1)->slices);
            overhangs = union_ex(pp);
        }
        
        // generate points following the shape of each island
        Points pillars_pos;
        const coordf_t spacing = scale_(this->config.support_material_spacing);
        const coordf_t radius  = scale_(this->sm_pillars_radius());
        for (ExPolygons::const_iterator it = overhangs.begin(); it != overhangs.end(); ++it) {
            // leave a radius/2 gap between pillars and contour to prevent lateral adhesion
            for (float inset = radius * 1.5;; inset += spacing) {
                // inset according to the configured spacing
                Polygons curr = offset(*it, -inset);
                if (curr.empty()) break;
                
                // generate points along the contours
                for (Polygons::const_iterator pg = curr.begin(); pg != curr.end(); ++pg) {
                    Points pp = pg->equally_spaced_points(spacing);
                    for (Points::const_iterator p = pp.begin(); p != pp.end(); ++p)
                        pillars_pos.push_back(*p);
                }
            }
        }
        
        // for each pillar, check which layers it applies to
        for (Points::const_iterator p = pillars_pos.begin(); p != pillars_pos.end(); ++p) {
            SupportPillar pillar(*p);
            bool object_hit = false;
            
            // check layers top-down
            for (int i = this->layers.size()-1; i >= 0; --i) {
                // check whether point is void in this layer
                if (!this->layers[i].slices.contains(*p)) {
                    // no slice contains the point, so it's in the void
                    if (pillar.top_layer > 0) {
                        // we have a pillar, so extend it
                        pillar.bottom_layer = i + this->config.raft_layers;
                    } else if (object_hit) {
                        // we don't have a pillar and we're below the object, so create one
                        pillar.top_layer = i + this->config.raft_layers;
                    }
                } else {
                    if (pillar.top_layer > 0) {
                        // we have a pillar which is not needed anymore, so store it and initialize a new potential pillar
                        this->sm_pillars.push_back(pillar);
                        pillar = SupportPillar(*p);
                    }
                    object_hit = true;
                }
            }
            if (pillar.top_layer > 0) this->sm_pillars.push_back(pillar);
        }
    }
    
    // generate a solid raft if requested
    // (do this after support material because we take support material shape into account)
    if (this->config.raft_layers > 0) {
        ExPolygons raft = this->layers.front().slices + overhangs;  // take support material into account
        raft = offset_ex(raft, scale_(this->config.raft_offset));
        for (int i = this->config.raft_layers; i >= 1; --i) {
            this->layers.insert(this->layers.begin(), Layer(0, first_lh + lh * (i-1)));
            this->layers.front().slices = raft;
        }
        
        // prepend total raft height to all sliced layers
        for (size_t i = this->config.raft_layers; i < this->layers.size(); ++i)
            this->layers[i].print_z += first_lh + lh * (this->config.raft_layers-1);
    }
}