package edu.stanford.rsl.tutorial.phantoms; /** * Simple class to show the Grid2D functionality. We use a Grid2D to create a uniform circle. * We use this as a first phantom to investigate parallel beam projection and back-projection. * * @author Recopra Summer Semester 2012 * */ public class TestObject1 extends Phantom { /** * The constructor takes two arguments to initialize the grid. The circle will be in the center and have a radius of 45% of the x-dimension. * Thus we recommend a grid size that is uniform in both directions. * @param x * @param y */ public TestObject1 (int x, int y){ super(x,y,"TestObject1"); // Create circle in the grid. boolean ascending = true; int numCircles = 20; double angleStep = Math.PI*2 / (float) numCircles; double radius = 0.03*x; double bigRadius = 0.4*x; double val = 1.d; for (int i = 0; i < numCircles; i++){ // if (i>= numCircles/2) continue; double angle = i * angleStep; int xCenter = (int) (x/2 + Math.cos(angle)*bigRadius); int yCenter = (int) (y/2 + Math.sin(angle)*bigRadius); for(int i1 = (int) (xCenter-radius*x -1); i1<xCenter+radius*x+1; i1++) { for(int j = 0; j<y; j++) { if( Math.pow(i1 - xCenter, 2) + Math.pow(j - yCenter, 2) <= (radius*radius) ) { if (ascending) val = (float) i / (numCircles-1); super.setAtIndex(i1, j, (float) val); } } } } } } /* * Copyright (C) 2010-2014 Andreas Maier * CONRAD is developed as an Open Source project under the GNU General Public License (GPL). */