1 files changed, 63 insertions, 0 deletions
diff --git a/examples/org.eclipse.swt.examples.paint/src/org/eclipse/swt/examples/paint/Figure.java b/examples/org.eclipse.swt.examples.paint/src/org/eclipse/swt/examples/paint/Figure.java
new file mode 100755
index 0000000000..e5d97a2e93
--- /dev/null
+++ b/examples/org.eclipse.swt.examples.paint/src/org/eclipse/swt/examples/paint/Figure.java
@@ -0,0 +1,63 @@
+package org.eclipse.swt.examples.paint;
+
+/*
+ * (c) Copyright IBM Corp. 2000, 2001.
+ * All Rights Reserved
+ */
+
+import org.eclipse.swt.graphics.*;
+
+/**
+ * Superinterface for all drawing objects.
+ * All drawing objects know how to render themselved to the screen and can draw a
+ * temporary version of themselves for previewing the general appearance of the
+ * object onscreen before it gets committed.
+ */
+public abstract class Figure {
+	/**
+	 * Draws an object to the specified GC
+	 * <p>
+	 * The GC must be set up as follows (and must be returned to this state before returning)
+	 * <ul>
+	 *   <li>setXORMode(false)
+	 * </ul>
+	 * </p>
+	 * 
+	 * @param gc the GC to draw on
+	 * @param offset the offset to add to virtual coordinates to get display coordinates
+	 */
+	public abstract void draw(GC gc, Point offset);
+
+	/**
+	 * Draws a preview copy of the object to the specified GC
+	 * <p>
+	 * The GC must be set up as follows (and must be returned to this state before returning)
+	 * <ul>
+	 *   <li>setXORMode(true)
+	 *   <li>setForeground(new Color(display, 255, 255, 255))
+	 *   <li>setBackground(new Color(display, 127, 127, 127))
+	 * </ul>
+	 * </p>
+	 * 
+	 * @param gc the GC to draw on
+	 * @param offset the offset to add to virtual coordinates to get display coordinates
+	 * @return object state that must be passed to erasePreview() later to erase this object
+	 */
+	public abstract Object drawPreview(GC gc, Point offset);
+
+	/**
+	 * Erases a preview copy of the object to the specified GC
+	 * <p>
+	 * Note that erasures are guaranteed to occur in the reverse order to the original drawing
+	 * order and that the GC's contents will be as they were when the drawPreview() that supplied
+	 * <code>rememberedState</code>returned.
+	 * </p><p>
+	 * The GC must be set up and restored as with drawPreview().
+	 * </p>
+	 * 
+	 * @param gc the GC to draw on
+	 * @param offset the offset to add to virtual coordinates to get display coordinates
+	 * @param rememberedState the state returned by a previous drawPreview() using this instance
+	 */
+	public abstract void erasePreview(GC gc, Point offset, Object rememberedState);
+}