multiVolumes.cs

/*
This file is part of MatterSlice. A commandline utility for 
generating 3D printing GCode.

Copyright (C) 2013 David Braam
Copyright (c) 2014, Lars Brubaker

MatterSlice is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

using System;
using System.Collections.Generic;
using System.Diagnostics;

using MatterSlice.ClipperLib;

namespace MatterHackers.MatterSlice
{
    using Polygon = List<IntPoint>;
    using Polygons = List<List<IntPoint>>;

    public static class MultiVolumes
    {
        public static void RemoveVolumesIntersections(List<SliceVolumeStorage> volumes)
        {
            //Go trough all the volumes, and remove the previous volume outlines from our own outline, so we never have overlapped areas.
            for (int volumeToRemoveFromIndex = volumes.Count-1; volumeToRemoveFromIndex >= 0; volumeToRemoveFromIndex--)
            {
                for (int volumeToRemoveIndex = volumeToRemoveFromIndex - 1; volumeToRemoveIndex >= 0; volumeToRemoveIndex--)
                {
                    for (int layerIndex = 0; layerIndex < volumes[volumeToRemoveFromIndex].layers.Count; layerIndex++)
                    {
                        SliceLayer layerToRemoveFrom = volumes[volumeToRemoveFromIndex].layers[layerIndex];
                        SliceLayer layerToRemove = volumes[volumeToRemoveIndex].layers[layerIndex];
                        for (int partToRemoveFromIndex = 0; partToRemoveFromIndex < layerToRemoveFrom.parts.Count; partToRemoveFromIndex++)
                        {
                            for (int partToRemove = 0; partToRemove < layerToRemove.parts.Count; partToRemove++)
                            {
                                layerToRemoveFrom.parts[partToRemoveFromIndex].outline = layerToRemoveFrom.parts[partToRemoveFromIndex].outline.CreateDifference(layerToRemove.parts[partToRemove].outline);
                            }
                        }
                    }
                }
            }
        }

        //Expand each layer a bit and then keep the extra overlapping parts that overlap with other volumes.
        //This generates some overlap in dual extrusion, for better bonding in touching parts.
        public static void OverlapMultipleVolumesSlightly(List<SliceVolumeStorage> volumes, int overlap)
        {
            if (volumes.Count < 2 || overlap <= 0)
            {
                return;
            }

            for (int layerIndex = 0; layerIndex < volumes[0].layers.Count; layerIndex++)
            {
                Polygons fullLayer = new Polygons();
                for (int volIdx = 0; volIdx < volumes.Count; volIdx++)
                {
                    SliceLayer layer1 = volumes[volIdx].layers[layerIndex];
                    for (int p1 = 0; p1 < layer1.parts.Count; p1++)
                    {
                        fullLayer = fullLayer.CreateUnion(layer1.parts[p1].outline.Offset(20));
                    }
                }
                fullLayer = fullLayer.Offset(-20);

                for (int volumeIndex = 0; volumeIndex < volumes.Count; volumeIndex++)
                {
                    SliceLayer layer1 = volumes[volumeIndex].layers[layerIndex];
                    for (int partIndex = 0; partIndex < layer1.parts.Count; partIndex++)
                    {
                        layer1.parts[partIndex].outline = fullLayer.CreateIntersection(layer1.parts[partIndex].outline.Offset(overlap / 2));
                    }
                }
            }
        }
    }
}