org.eclipse.swt.examples.paint.SolidPolygonFigure.java Source code

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Here is the source code for org.eclipse.swt.examples.paint.SolidPolygonFigure.java

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/*******************************************************************************
 * Copyright (c) 2000, 2013 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.examples.paint;

import org.eclipse.swt.graphics.*;

/**
 * 2D Line object
 */
public class SolidPolygonFigure extends Figure {
    private Color color;
    private int[] points;

    /**
     * Constructs a SolidPolygon
     * These objects are defined by a sequence of vertices.
     *
     * @param color the color for this object
     * @param vertices the array of vertices making up the polygon
     * @param numPoint the number of valid points in the array (n >= 3)
     */
    public SolidPolygonFigure(Color color, Point[] vertices, int numPoints) {
        this.color = color;
        this.points = new int[numPoints * 2];
        for (int i = 0; i < numPoints; ++i) {
            points[i * 2] = vertices[i].x;
            points[i * 2 + 1] = vertices[i].y;
        }
    }

    @Override
    public void draw(FigureDrawContext fdc) {
        int[] drawPoints = new int[points.length];
        for (int i = 0; i < points.length; i += 2) {
            drawPoints[i] = points[i] * fdc.xScale - fdc.xOffset;
            drawPoints[i + 1] = points[i + 1] * fdc.yScale - fdc.yOffset;
        }
        fdc.gc.setBackground(color);
        fdc.gc.fillPolygon(drawPoints);
    }

    @Override
    public void addDamagedRegion(FigureDrawContext fdc, Region region) {
        int xmin = Integer.MAX_VALUE, ymin = Integer.MAX_VALUE;
        int xmax = Integer.MIN_VALUE, ymax = Integer.MIN_VALUE;

        for (int i = 0; i < points.length; i += 2) {
            if (points[i] < xmin)
                xmin = points[i];
            if (points[i] > xmax)
                xmax = points[i];
            if (points[i + 1] < ymin)
                ymin = points[i + 1];
            if (points[i + 1] > ymax)
                ymax = points[i + 1];
        }
        region.add(fdc.toClientRectangle(xmin, ymin, xmax, ymax));
    }
}