geogramMeshCurves.cpp

void meshOutlines(const vector<vector<array<float, 2> > > & crvs,vector<array<float, 2> > & outPts, vector<unsigned int> & indices) {
	GEO::CDT2d cdt;
	if (crvs.size() == 0) return;
	//get bounding box
	float minX = crvs[0][0][0], maxX = crvs[0][0][0], minY = crvs[0][0][1], maxY = crvs[0][0][1];
	vector<double> pts;
	for (int c = 0; c < crvs.size();++c) {
		auto & crv = crvs[c];
		float area = 0;
		for (int i = 0; i < crv.size(); ++i) {
			pts.push_back(crv[i][0]);
			pts.push_back(crv[i][1]);
			minX = min(crv[i][0], minX);
			maxX = max(crv[i][0], maxX);
			minY = min(crv[i][1], minY);
			maxY = max(crv[i][1], maxY);
		}
	}
	cdt.create_enclosing_rectangle(minX-10, minY-10, maxX+10, maxY+10);
	vector<GEO::index_t> newIndices(pts.size() / 2);
	cdt.insert(pts.size()/2, pts.data(),newIndices.data());

	int currIndex = 0;
	for (auto & crv : crvs) {
		for (int i = 0; i < crv.size(); ++i) {
			cdt.insert_constraint(newIndices[i + currIndex], newIndices[(i + 1) % crv.size() + currIndex]);
		}
		currIndex += crv.size();
	}

	cdt.remove_external_triangles();
	cdt.remove_holes();
	auto numTriangles = cdt.nT();
	for (int i = 0; i < numTriangles; ++i) {
		int index1 = cdt.Tv(i, 0)-4;
		int index2 = cdt.Tv(i, 1)-4;
		int index3 = cdt.Tv(i, 2)-4;
		
		indices.push_back(index1);
		indices.push_back(index2);
		indices.push_back(index3);
	}
	for (int i = 4; i < cdt.nv(); ++i) {
		auto p = cdt.point(i);
		outPts.push_back({p.x, p.y});
	}
}