1 // Copyright 2002, FreeHEP.
2 package org.freehep.graphicsio.emf.gdi;
3
4 import java.awt.Point;
5 import java.io.IOException;
6
7 import org.freehep.graphicsio.emf.EMFInputStream;
8 import org.freehep.graphicsio.emf.EMFOutputStream;
9 import org.freehep.graphicsio.emf.EMFTag;
10 import org.freehep.graphicsio.emf.EMFRenderer;
11
12 /**
13 * SetViewportOrgEx TAG.
14 *
15 * @author Mark Donszelmann
16 * @version $Id: SetViewportOrgEx.java 10367 2007-01-22 19:26:48Z duns $
17 */
18 public class SetViewportOrgEx extends EMFTag {
19
20 private Point point;
21
22 public SetViewportOrgEx() {
23 super(12, 1);
24 }
25
26 public SetViewportOrgEx(Point point) {
27 this();
28 this.point = point;
29 }
30
31 public EMFTag read(int tagID, EMFInputStream emf, int len)
32 throws IOException {
33
34 return new SetViewportOrgEx(emf.readPOINTL());
35 }
36
37 public void write(int tagID, EMFOutputStream emf) throws IOException {
38 emf.writePOINTL(point);
39 }
40
41 public String toString() {
42 return super.toString() + "\n point: " + point;
43 }
44
45 /**
46 * displays the tag using the renderer
47 *
48 * @param renderer EMFRenderer storing the drawing session data
49 */
50 public void render(EMFRenderer renderer) {
51 // The SetViewportOrgEx function specifies which device point maps
52 // to the viewport origin (0,0).
53
54 // This function (along with SetViewportExtEx and SetWindowExtEx) helps
55 // define the mapping from the logical coordinate space (also known as a
56 // window) to the device coordinate space (the viewport). SetViewportOrgEx
57 // specifies which device point maps to the logical point (0,0). It has the
58 // effect of shifting the axes so that the logical point (0,0) no longer
59 // refers to the upper-left corner.
60 renderer.setViewportOrigin(point);
61 renderer.resetTransformation();
62 }
63 }