Examples with HalfEdge maspack.geometry.HalfEdge used on opensource projects

Example 21 with HalfEdge

use of maspack.geometry.HalfEdge in project artisynth_core by artisynth.

the class GtsWriter method writeMesh.

public void writeMesh(PolygonalMesh mesh) throws IOException {
    PrintWriter pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(myOstream)));
    int[] oldIdxs = new int[mesh.numVertices()];
    int vidx = 0;
    for (Vertex3d vtx : mesh.getVertices()) {
        // protect vertex indices numbers
        oldIdxs[vidx] = vtx.getIndex();
        vtx.setIndex(vidx);
        vidx++;
    }
    LinkedHashMap<Edge, Integer> edgeList = new LinkedHashMap<Edge, Integer>();
    for (Face f : mesh.getFaces()) {
        HalfEdge he0 = f.firstHalfEdge();
        HalfEdge he = he0;
        do {
            HalfEdge next = he.getNext();
            Edge edge = new Edge(he.head, next.head);
            if (edgeList.get(edge) == null) {
                edgeList.put(edge, edgeList.size());
            }
            he = next;
        } while (he != he0);
    }
    pw.println(mesh.numVertices() + " " + edgeList.size() + " " + mesh.numFaces());
    for (Vertex3d vtx : mesh.getVertices()) {
        vtx.pnt.write(pw, myFmt);
        pw.println("");
    }
    for (Edge edge : edgeList.keySet()) {
        pw.println((edge.myVtx1.getIndex() + 1) + " " + (edge.myVtx2.getIndex() + 1));
    }
    for (Face f : mesh.getFaces()) {
        HalfEdge he0 = f.firstHalfEdge();
        HalfEdge he = he0;
        do {
            HalfEdge next = he.getNext();
            Edge edge = new Edge(he.head, next.head);
            Integer idx = edgeList.get(edge);
            pw.print((idx + 1) + " ");
            he = next;
        } while (he != he0);
        pw.println("");
    }
    // restore vertex indices
    vidx = 0;
    for (Vertex3d vtx : mesh.getVertices()) {
        vtx.setIndex(oldIdxs[vidx]);
        vidx++;
    }
}

Example 22 with HalfEdge

use of maspack.geometry.HalfEdge in project artisynth_core by artisynth.

the class MeshIntersectingProbe method findNextEdge.

// NOTE: only works for convex faces (so, triangular is okay)
// finds the next edge while clipping around in a circle
private static HalfEdge findNextEdge(LinkedList<Point3d> contour, ArrayList<Face> faceList, Intersector2d ti, SplitStorage info, Vector3d vx, Vector3d vy, Point3d o) {
    Vector3d dir = new Vector3d();
    Point3d vtxp = info.vtx.getWorldPoint();
    Point2d vtx2d = Intersector2d.get2dCoordinate(vtxp, vx, vy, o);
    dir.sub(contour.get(info.idx + 1), contour.get(info.idx));
    for (Face face : faceList) {
        HalfEdge he0 = face.getEdge(0);
        HalfEdge he = he0;
        do {
            if (info.vtx != he.head && info.vtx != he.tail) {
                Point2d p1 = Intersector2d.get2dCoordinate(he.head.getWorldPoint(), vx, vy, o);
                Point2d p2 = Intersector2d.get2dCoordinate(he.tail.getWorldPoint(), vx, vy, o);
                ArrayList<Point2d> pnts = new ArrayList<Point2d>();
                Vector2d lineDir = Intersector2d.get2dVector(dir, vx, vy);
                int npoints = ti.intersectLineLineSegment(vtx2d, lineDir, p1, p2, pnts);
                if (npoints == 1) {
                    Point3d p = Intersector2d.get3dCoordinate(pnts.get(0), vx, vy, o);
                    Vector3d ldir = new Vector3d(p.x - vtxp.x, p.y - vtxp.y, p.z - vtxp.z);
                    // check direction
                    if (ldir.dot(dir) > -ti.epsilon) {
                        // check if we passed the next point
                        Point3d pNext = contour.get(info.idx + 1);
                        if (ldir.norm() < pNext.distance(vtxp) + ti.epsilon) {
                            if (p.distance(pNext) < ti.epsilon) {
                                // move to next point
                                info.idx++;
                            }
                            info.vtx = createOrGetVertex(p, face.getVertices(), ti.epsilon);
                            return he;
                        } else {
                            // advance to next vertex
                            info.vtx = createOrGetVertex(pNext, face.getVertices(), ti.epsilon);
                            info.face = face;
                            // move to next point
                            info.idx++;
                            return null;
                        }
                    }
                }
            }
            he = he.getNext();
        } while (he != he0);
    }
    info.face = null;
    return null;
}

Example 23 with HalfEdge

use of maspack.geometry.HalfEdge in project artisynth_core by artisynth.

the class MeshIntersectingProbe method clipMesh.

// does the clipping of a planar surface based on a contour
private void clipMesh(PolygonalMesh surface, LinkedList<Point3d> contour, double tol) {
    SplitStorage info = new SplitStorage();
    Intersector2d ti = new Intersector2d();
    ti.setEpsilon(tol);
    // coordinate system
    Vector3d vx = new Vector3d();
    Vector3d vy = new Vector3d();
    Point3d o = getPosition();
    XGridToWorld.R.getColumn(0, vx);
    XGridToWorld.R.getColumn(1, vy);
    OBBTree obbt = new OBBTree(surface, 2, tol);
    ArrayList<Face> faceList = null;
    while (info.idx + 1 < contour.size()) {
        if (info.vtx == null) {
            Face face = findNextFace(contour.get(info.idx), contour, obbt, ti, vx, vy, o, info);
            // so now I have a vertex and a face it lies on
            if (face != null) {
                // we may be on multiple faces
                faceList = findFaces(info.vtx.getWorldPoint(), obbt, vx, vy, o, tol);
                for (Face f : faceList) {
                    splitFace(surface, f, info.vtx, tol);
                }
            }
        } else {
            // find all faces this vertex is on, project in direction of contour
            faceList = getFaces(info.vtx);
            HalfEdge he = findNextEdge(contour, faceList, ti, info, vx, vy, o);
            if (he != null) {
                // we landed on an edge
                Face oppFace = null;
                if (he.opposite != null) {
                    oppFace = he.opposite.getFace();
                }
                splitFace(surface, he.getFace(), info.vtx, tol);
                if (oppFace != null) {
                    splitFace(surface, oppFace, info.vtx, tol);
                }
            } else if (info.face != null) {
                splitFace(surface, info.face, info.vtx, tol);
            } else {
                // move to next point
                info.idx++;
                info.vtx = null;
            }
        }
    }
}

Example 24 with HalfEdge

use of maspack.geometry.HalfEdge in project artisynth_core by artisynth.

the class SurfaceMeshContourIxer method robustIntersectionWithFace.

/*
    * Test for intersection using adaptive exact arithmetic and SOS tiebreaking.
    */
protected boolean robustIntersectionWithFace(HalfEdge he, Face face, IntersectionPoint mip, boolean edgeOnMesh0) {
    HalfEdge he0 = face.firstHalfEdge();
    Vertex3d v = he0.tail;
    if (v == he.head)
        return false;
    if (v == he.tail)
        return false;
    v = he0.head;
    if (v == he.head)
        return false;
    if (v == he.tail)
        return false;
    v = he0.getNext().head;
    if (v == he.head)
        return false;
    if (v == he.tail)
        return false;
    int res = RobustPreds.intersectEdgeTriangle(mip, he, face, myMaxLength, edgeOnMesh0, /*worldCoords=*/
    true);
    if (res == 0) {
        return false;
    } else {
        mip.edge = he;
        mip.face = face;
        // mip.edgeOnMesh0 = edgeOnMesh0;
        mip.intersectionCode = res;
        // mip.degeneracies = (res & RobustPreds.DEGENERACY_MASK);
        return true;
    }
}

Example 25 with HalfEdge

use of maspack.geometry.HalfEdge in project artisynth_core by artisynth.

the class MeshThicken method adjacentFacesCrossNormal.

private boolean adjacentFacesCrossNormal(Vertex3d vtx, Vector3d nrm) {
    double lastdot = 1;
    Iterator<HalfEdge> it = vtx.getIncidentHalfEdges();
    while (it.hasNext()) {
        HalfEdge he = it.next();
        double dot = he.getFace().getNormal().dot(nrm);
        if (dot * lastdot <= 0) {
            return true;
        }
        lastdot = dot;
    }
    return false;
}