示例#1
0
void FEdgeXDetector::postProcessSuggestiveContourFace(WXFace *iFace) {

    // Compute the derivative of the radial curvature in the radial direction,
    // at the two extremities of the smooth edge.
    // If the derivative is smaller than a given threshold _kr_derivative_epsilon,
    // discard the edge.

    // Find the suggestive contour layer of the face (zero or one edge).
    vector<WXFaceLayer*> sc_layers;
    iFace->retrieveSmoothEdgesLayers(Nature::SUGGESTIVE_CONTOUR, sc_layers);
    if(sc_layers.empty())
        return;

    WXFaceLayer *sc_layer;
    sc_layer = sc_layers[0];

    // Compute the derivative value at each vertex of the face, and add it in a vector.
    vector<real> kr_derivatives;

    unsigned vertices_nb = iFace->numberOfVertices();
    WXVertex *v, *opposite_vertex_a, *opposite_vertex_b;
    WXFace *wxf;
    WOEdge *opposite_edge;
    Vec3r opposite_edge_vec, normal_vec, radial_normal_vec, er_vec, v_vec, inter, inter1, inter2, tmp_vec;
    GeomUtils::intersection_test res;
    real kr(0), kr1(0), kr2(0), t;

    for (unsigned i = 0; i < vertices_nb; ++i) {
        v = (WXVertex*)(iFace->GetVertex(i));

        // v is a singular vertex, skip it.
        if (v->isBoundary()) {
            kr_derivatives.push_back(0);
            continue;
        }

        v_vec = v->GetVertex();
        er_vec = v->curvatures()->er;

        // For each vertex, iterate on its adjacent faces.
        for (WVertex::face_iterator fit = v->faces_begin(), fitend = v->faces_end();
             fit != fitend;
             ++fit) {
            wxf = dynamic_cast<WXFace*>(*fit);
            if(!(wxf->getOppositeEdge(v, opposite_edge)))
                continue;

            opposite_vertex_a = (WXVertex*)opposite_edge->GetaVertex();
            opposite_vertex_b = (WXVertex*)opposite_edge->GetbVertex();
            opposite_edge_vec = opposite_vertex_b->GetVertex() - opposite_vertex_a->GetVertex();
            normal_vec = wxf->GetVertexNormal(v); // FIXME: what about e1 ^ e2 ?
            radial_normal_vec = er_vec ^ normal_vec;

            // Test wether the radial plan intersects with the edge at the opposite of v.
            res = GeomUtils::intersectRayPlane(opposite_vertex_a->GetVertex(), opposite_edge_vec,
                                               radial_normal_vec, -(v_vec * radial_normal_vec),
                                               t,
                                               1.e-06);

            // If there is an intersection, compute the value of the derivative ath that point.
            if ((res == GeomUtils::DO_INTERSECT) && (t >= 0) && (t <= 1)) {
                kr = t * opposite_vertex_a->curvatures()->Kr + (1 - t) * opposite_vertex_b->curvatures()->Kr;
                inter = opposite_vertex_a->GetVertex() + t * opposite_edge_vec;
                tmp_vec = inter - v->GetVertex();
                // Is it kr1 or kr2?
                if (tmp_vec * er_vec > 0) {
                    kr2 = kr;
                    inter2 = inter;
                } else {
                    kr1 = kr;
                    inter1 = inter;
                }
            }
        }

        // Now we have kr1 and kr2 along the radial direction, for one vertex of iFace.
        // We have to compute the derivative of kr for that vertex, equal to:
        // (kr2 - kr1) / dist(inter1, inter2).
        // Then we add it to the vector of derivatives.
        v->curvatures()->dKr = (kr2 - kr1) / (inter2 - inter1).norm();
        kr_derivatives.push_back(v->curvatures()->dKr);
    }

    // At that point, we have the derivatives for each vertex of iFace.
    // All we have to do now is to use linear interpolation to compute the values at
    // the extremities of the smooth edge.
    WXSmoothEdge *sc_edge = sc_layer->getSmoothEdge();
    WOEdge *sc_oedge = sc_edge->woea();
    t = sc_edge->ta();
    if (t * kr_derivatives[iFace->GetIndex(sc_oedge->GetaVertex())] +
            (1 - t) * kr_derivatives[iFace->GetIndex(sc_oedge->GetbVertex())] < _kr_derivative_epsilon) {
        sc_layer->removeSmoothEdge();
        return;
    }
    sc_oedge = sc_edge->woeb();
    t = sc_edge->tb();
    if (t * kr_derivatives[iFace->GetIndex(sc_oedge->GetaVertex())] +
            (1 - t) * kr_derivatives[iFace->GetIndex(sc_oedge->GetbVertex())] < _kr_derivative_epsilon)
        sc_layer->removeSmoothEdge();
}
示例#2
0
void FEdgeXDetector::ProcessRidgeFace(WXFace *iFace)
{
	// RIDGE LAYER
	// Compute the RidgeFunction, that is the derivative of the ppal curvature along e1 at each vertex of the face
	WVertex *v;
	Vec3r v1v2;
	real t;
	vector<WXFaceLayer*> SmoothLayers;
	WXFaceLayer *faceLayer;
	Face_Curvature_Info *layer_info;
	real K1_a(0), K1_b(0);
	Vec3r Inter_a, Inter_b;

	// find the ridge layer of the face
	iFace->retrieveSmoothLayers(Nature::RIDGE, SmoothLayers);
	if ( SmoothLayers.size()!=1 )
		return;
	faceLayer = SmoothLayers[0];
	// retrieve the curvature info of this layer
	layer_info = (Face_Curvature_Info *)faceLayer->userdata;

	int numVertices = iFace->numberOfVertices();
	for (int i = 0; i < numVertices; i++) {
		v = iFace->GetVertex(i);
		// vec_curvature_info[i] contains the curvature info of this vertex
		Vec3r e2 = layer_info->vec_curvature_info[i]->K2*layer_info->vec_curvature_info[i]->e2;
		Vec3r e1 = layer_info->vec_curvature_info[i]->K1*layer_info->vec_curvature_info[i]->e1;
		e2.normalize();

		WVertex::face_iterator fit = v->faces_begin();
		WVertex::face_iterator fitend = v->faces_end();
		for (; fit != fitend; ++fit) {
			WXFace *wxf = dynamic_cast<WXFace*>(*fit);
			WOEdge *oppositeEdge;
			if (!(wxf->getOppositeEdge(v, oppositeEdge)))
				continue;
			v1v2 = oppositeEdge->GetbVertex()->GetVertex() - oppositeEdge->GetaVertex()->GetVertex();
			GeomUtils::intersection_test res;
			res = GeomUtils::intersectRayPlane(oppositeEdge->GetaVertex()->GetVertex(), v1v2, e2, -(v->GetVertex()*e2),
			                                   t, 1.0e-06);
			if ((res == GeomUtils::DO_INTERSECT) && (t >= 0.0) && (t <= 1.0)) {
				vector<WXFaceLayer*> second_ridge_layer;
				wxf->retrieveSmoothLayers(Nature::RIDGE, second_ridge_layer);
				if (second_ridge_layer.size() != 1)
					continue;
				Face_Curvature_Info *second_layer_info = (Face_Curvature_Info*)second_ridge_layer[0]->userdata;

				unsigned index1 = wxf->GetIndex(oppositeEdge->GetaVertex());
				unsigned index2 = wxf->GetIndex(oppositeEdge->GetbVertex());
				real K1_1 = second_layer_info->vec_curvature_info[index1]->K1;
				real K1_2 = second_layer_info->vec_curvature_info[index2]->K1;
				real K1 = (1.0 - t) * K1_1 + t * K1_2;
				Vec3r inter((1.0 - t) * oppositeEdge->GetaVertex()->GetVertex() +
				            t * oppositeEdge->GetbVertex()->GetVertex());
				Vec3r vtmp(inter - v->GetVertex());
				// is it K1_a or K1_b ?
				if (vtmp * e1 > 0) {
					K1_b = K1;
					Inter_b = inter;
				}
				else {
					K1_a = K1;
					Inter_a = inter;
				}
			}
		}
		// Once we have K1 along the ppal direction compute the derivative : K1b - K1a put it in DotP
		//real d = fabs(K1_b) - fabs(K1_a);
		real d = 0;
		real threshold = _meanK1 + (_maxK1 - _meanK1) / 7.0;
		//real threshold = _meanK1;
		//if ((fabs(K1_b) > threshold) || ((fabs(K1_a) > threshold)))
		d = (K1_b) - (K1_a) / (Inter_b - Inter_a).norm();
		faceLayer->PushDotP(d);
		//faceLayer->PushDotP(layer_info->vec_curvature_info[i]->K1);
	}

	// Make the values relevant by checking whether all principal directions have the "same" direction:
	Vec3r e0((layer_info->vec_curvature_info[0]->K1 * layer_info->vec_curvature_info[0]->e1));
	e0.normalize();
	Vec3r e1((layer_info->vec_curvature_info[1]->K1 * layer_info->vec_curvature_info[1]->e1));
	e1.normalize();
	Vec3r e2((layer_info->vec_curvature_info[2]->K1 * layer_info->vec_curvature_info[2]->e1));
	e2.normalize();
	if (e0 * e1 < 0)
		// invert dotP[1]
		faceLayer->ReplaceDotP(1, -faceLayer->dotP(1));
	if (e0 * e2 < 0)
		// invert dotP[2]
		faceLayer->ReplaceDotP(2, -faceLayer->dotP(2));

#if 0 // remove the weakest values;
	real minDiff = (_maxK1 - _minK1) / 10.0;
	real minDiff = _meanK1;
	if ((faceLayer->dotP(0) < minDiff) && (faceLayer->dotP(1) < minDiff) && (faceLayer->dotP(2) < minDiff)) {
		faceLayer->ReplaceDotP(0, 0);
		faceLayer->ReplaceDotP(1, 0);
		faceLayer->ReplaceDotP(2, 0);
	}
#endif
}