boofcv.alg.feature.detect.squares.SquareNode Maven / Gradle / Ivy
/*
* Copyright (c) 2011-2015, Peter Abeles. All Rights Reserved.
*
* This file is part of BoofCV (http://boofcv.org).
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package boofcv.alg.feature.detect.squares;
import georegression.struct.point.Point2D_F64;
import georegression.struct.shapes.Polygon2D_F64;
/**
* Graph representation of square blobs. Each blob can be connected to at most 4 other shapes which are directly
* adjacent of one of the sides.
*
* @author Peter Abeles
*/
public class SquareNode {
public static final int RESET_GRAPH = -2;
// polygon which this node represents.
// cw or ccw ordering of edges doesn't matter
public Polygon2D_F64 corners;
// intersection of line 0 and 2 with 1 and 3.
public Point2D_F64 center = new Point2D_F64();
// length of sides. side = i and i+1
public double sideLengths[] = new double[4];
// the largest length
public double largestSide;
// marker used to indicate that this has been traversed by different algorithms
public int graph;
// edges in the graph. One for each side in the shape
public SquareEdge edges[] = new SquareEdge[4];
/**
* Finds the Euclidean distance squared of the closest corner to point p
*/
public double distanceSqCorner( Point2D_F64 p ) {
double best = Double.MAX_VALUE;
for (int i = 0; i < 4; i++) {
double d = corners.get(i).distance2(p);
if( d < best ) {
best = d;
}
}
return best;
}
/**
* Discards previous information
*/
public void reset() {
corners = null;
graph = RESET_GRAPH;
largestSide = 0;
for (int i = 0; i < 4; i++) {
if ( edges[i] != null )
throw new RuntimeException("BUG!");
sideLengths[i] = 0;
}
}
/**
* Computes the number of edges attached to this node
*/
public int getNumberOfConnections() {
int ret = 0;
for (int i = 0; i < 4; i++) {
if( edges[i] != null )
ret++;
}
return ret;
}
}