AT att88

att88 / planarity.cpp

Created February 28, 2011 12:25

Compute Planarity of a 3D point using approach 1.

	double PointCloud::computePlanarity(int pointIndex) {
	PointCloud p;
	p.points.push_back(points[pointIndex]);
	for (int i = 0; i < (int)points.size(); i++) {
	if(i != pointIndex && points[i].distanceTo(points[pointIndex]) <= MaxEPS) {
	p.points.push_back(points[i]);
	}
	}

	Plane plane = p.bestFittingPlane();

att88 / point_plane_distance.cpp

Created February 28, 2011 12:09

Distance from Point (x, y, z) to Plane (ax + by + cz + d = 0)

	double Point::distanceTo(Plane p) {
	return abs( p.a * x + p.b * y + p.c * z + p.d) /
	sqrt(p.a * p.a + p.b * p.b + p.c * p.c);
	}

att88 / best_fitting_plane.cpp

Created February 28, 2011 11:48

Best Fitting Plane of a 3D Point Cloud with PCA and GSL

	Plane PointCloud::bestFittingPlane() {
	computeCovarianceMatrix();

	gsl_matrix * m = gsl_matrix_alloc(3, 3);
	for (int i = 0; i < 3; i++)
	for (int j = 0; j < 3; j++)
	gsl_matrix_set(m, i, j, covarianceMatrix[i][j]);

	gsl_vector *eval = gsl_vector_alloc(3);
	gsl_matrix *evec = gsl_matrix_alloc(3, 3);

att88 / covariance_matrix.cpp

Created February 28, 2011 11:45

Compute the Covariance Matrix of a 3D Point Cloud

	void PointCloud::computeCovarianceMatrix() {
	double means[3] = {0, 0, 0};
	for (int i = 0; i < points.size(); i++)
	means[0] += points[i].x,
	means[1] += points[i].y,
	means[2] += points[i].z;
	means[0] /= points.size(), means[1] /= points.size(), means[2] /= points.size();

	for (int i = 0; i < 3; i++)
	for (int j = 0; j < 3; j++) {