C++ ConvexHull::leftOfLine方法代码示例

//TODO: Regard some kind of aspect ration (input)
//(then also the rotation of a single component makes sense)
void ComponentSplitterLayout::reassembleDrawings(GraphAttributes& GA, const Array<List<node> > &nodesInCC)
{
	int numberOfComponents = nodesInCC.size();

	Array<IPoint> box;
	Array<IPoint> offset;
	Array<DPoint> oldOffset;
	Array<double> rotation;
	ConvexHull CH;

	// rotate components and create bounding rectangles

	//iterate through all components and compute convex hull
	for (int j = 0; j < numberOfComponents; j++)
	{
		//todo: should not use std::vector, but in order not
		//to have to change all interfaces, we do it anyway
		std::vector<DPoint> points;

		//collect node positions and at the same time center average
		// at origin
		double avg_x = 0.0;
		double avg_y = 0.0;
		for (node v : nodesInCC[j])
		{
			DPoint dp(GA.x(v), GA.y(v));
			avg_x += dp.m_x;
			avg_y += dp.m_y;
			points.push_back(dp);
		}
		avg_x /= nodesInCC[j].size();
		avg_y /= nodesInCC[j].size();

		//adapt positions to origin
		int count = 0;
		//assume same order of vertices and positions
		for (node v : nodesInCC[j])
		{
			//TODO: I am not sure if we need to update both
			GA.x(v) = GA.x(v) - avg_x;
			GA.y(v) = GA.y(v) - avg_y;
			points.at(count).m_x -= avg_x;
			points.at(count).m_y -= avg_y;

			count++;
		}

		// calculate convex hull
		DPolygon hull = CH.call(points);

		double best_area = numeric_limits<double>::max();
		DPoint best_normal;
		double best_width = 0.0;
		double best_height = 0.0;

		// find best rotation by using every face as rectangle border once.
		for (DPolygon::iterator j = hull.begin(); j != hull.end(); ++j) {
			DPolygon::iterator k = hull.cyclicSucc(j);

			double dist = 0.0;
			DPoint norm = CH.calcNormal(*k, *j);
			for (const DPoint &z : hull) {
				double d = CH.leftOfLine(norm, z, *k);
				if (d > dist) {
					dist = d;
				}
			}

			double left = 0.0;
			double right = 0.0;
			norm = CH.calcNormal(DPoint(0, 0), norm);
			for (const DPoint &z : hull) {
				double d = CH.leftOfLine(norm, z, *k);
				if (d > left) {
					left = d;
				}
				else if (d < right) {
					right = d;
				}
			}
			double width = left - right;

			dist = max(dist, 1.0);
			width = max(width, 1.0);

			double area = dist * width;

			if (area <= best_area) {
				best_height = dist;
				best_width = width;
				best_area = area;
				best_normal = CH.calcNormal(*k, *j);
			}
		}

		if (hull.size() <= 1) {
			best_height = 1.0;
			best_width = 1.0;
//.........这里部分代码省略.........