plugins/org.eclipse.fordiac.ide.gef/src/org/eclipse/fordiac/ide/gef/editparts/ZoomScalableFreeformRootEditPart.java - gerrit/4diac/org.eclipse.4diac.ide - Git at Google

 /*******************************************************************************
  * Copyright (c) 2008, 2021 Profactor GbmH, fortiss GmbH, Johannes Kepler University
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
  * http://www.eclipse.org/legal/epl-2.0.
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *   Gerhard Ebenhofer, Alois Zoitl
  *     - initial API and implementation and/or initial documentation
  *   Alois Zoitl - Changed grid layer so that it shows every 10th and 5th line
  *                 emphasized
  *               - added autoscroll to marquee drag tracker
  *               - moved incremental growing canvas from FBNetworkRootEditPart to
  *                 here so that all graphical editors can have it
  *******************************************************************************/
 package org.eclipse.fordiac.ide.gef.editparts;

 import java.util.ArrayList;
 import java.util.List;

 import org.eclipse.draw2d.ConnectionLayer;
 import org.eclipse.draw2d.Figure;
 import org.eclipse.draw2d.FigureCanvas;
 import org.eclipse.draw2d.FreeformFigure;
 import org.eclipse.draw2d.FreeformLayer;
 import org.eclipse.draw2d.FreeformLayeredPane;
 import org.eclipse.draw2d.FreeformLayout;
 import org.eclipse.draw2d.FreeformListener;
 import org.eclipse.draw2d.FreeformViewport;
 import org.eclipse.draw2d.Graphics;
 import org.eclipse.draw2d.IFigure;
 import org.eclipse.draw2d.LayeredPane;
 import org.eclipse.draw2d.ScalableFigure;
 import org.eclipse.draw2d.ScalableFreeformLayeredPane;
 import org.eclipse.draw2d.Viewport;
 import org.eclipse.draw2d.geometry.Dimension;
 import org.eclipse.draw2d.geometry.Point;
 import org.eclipse.draw2d.geometry.Rectangle;
 import org.eclipse.fordiac.ide.gef.draw2d.SingleLineBorder;
 import org.eclipse.fordiac.ide.model.ui.editors.AdvancedScrollingGraphicalViewer;
 import org.eclipse.gef.DragTracker;
 import org.eclipse.gef.EditPart;
 import org.eclipse.gef.EditPartViewer;
 import org.eclipse.gef.Request;
 import org.eclipse.gef.RequestConstants;
 import org.eclipse.gef.editparts.FreeformGraphicalRootEditPart;
 import org.eclipse.gef.editparts.GridLayer;
 import org.eclipse.gef.editparts.GuideLayer;
 import org.eclipse.gef.editparts.ScalableFreeformRootEditPart;
 import org.eclipse.gef.editparts.ZoomManager;
 import org.eclipse.gef.requests.SelectionRequest;
 import org.eclipse.gef.tools.MarqueeDragTracker;
 import org.eclipse.gef.ui.actions.ActionRegistry;
 import org.eclipse.gef.ui.actions.ZoomInAction;
 import org.eclipse.gef.ui.actions.ZoomOutAction;
 import org.eclipse.jface.action.IAction;
 import org.eclipse.jface.commands.ActionHandler;
 import org.eclipse.jface.resource.ColorRegistry;
 import org.eclipse.jface.viewers.StructuredSelection;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.MouseEvent;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.ui.IWorkbenchPartSite;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.handlers.IHandlerService;

 public class ZoomScalableFreeformRootEditPart extends ScalableFreeformRootEditPart {

 	/**
 	 * Grid layer that draws the grid in dashed lines and every X line solid to give
 	 * the grid more structure
 	 */
 	private static class MajorMinorGridLayer extends GridLayer {
 		private static final double MIN_ABSOLUTE_INTERLEAVE = 5.0;

 		private static final int MAJOR_INTERLEAVE = 10; // draw each 10th line thicker dashed to give the grid more
 		// structure
 		private static final int MEDIUM_INTERLEAVE = 5; // draw each 5th line medium dashed to give the grid more
 		// structure

 		private static final float[] GRID_MINOR_DASHES_STYLE = new float[] { 1.0f, 5.0f };
 		private static final float[] GRID_MEDIUM_DASHES_STYLE = new float[] { 2.0f, 4.0f };
 		private static final float[] GRID_MAJOR_DASHES_STYLE = new float[] { 4.0f, 2.0f };

 		@Override
 		protected void paintGrid(final Graphics g) {
 			final int origLineStyle = g.getLineStyle();
 			g.setLineStyle(Graphics.LINE_CUSTOM);

 			final Rectangle clip = g.getClip(Rectangle.SINGLETON);

 			if (gridX > 0) {
 				drawVerLines(g, clip);
 			}

 			if (gridY > 0) {
 				drawHorLines(g, clip);
 			}
 			g.setLineStyle(origLineStyle);
 		}

 		private void drawVerLines(final Graphics g, final Rectangle clip) {
 			final int majorInterleaveX = gridX * MAJOR_INTERLEAVE;
 			final int medInterleaveX = gridX * MEDIUM_INTERLEAVE;
 			final int realInterleaveX = determineInterleave(gridX, medInterleaveX, majorInterleaveX, g.getAbsoluteScale());

 			if (realInterleaveX > 0) {
 				for (int i = getLineStart(origin.x, clip.x, realInterleaveX); i < clip.x
 						+ clip.width; i += realInterleaveX) {
 					setLineStyle(g, i, origin.x, majorInterleaveX, medInterleaveX);
 					g.drawLine(i, clip.y, i, clip.y + clip.height);
 				}
 			}
 		}

 		private void drawHorLines(final Graphics g, final Rectangle clip) {
 			final int majorInterleaveY = gridY * MAJOR_INTERLEAVE;
 			final int medInterleaveY = gridY * MEDIUM_INTERLEAVE;
 			final int realInterleaveY = determineInterleave(gridY, medInterleaveY, majorInterleaveY, g.getAbsoluteScale());
 			if (realInterleaveY > 0) {
 				for (int i = getLineStart(origin.y, clip.y, realInterleaveY); i < clip.y
 						+ clip.height; i += realInterleaveY) {
 					setLineStyle(g, i, origin.y, majorInterleaveY, medInterleaveY);
 					g.drawLine(clip.x, i, clip.x + clip.width, i);
 				}
 			}
 		}

 		private static int determineInterleave(final int interleave, final int medInterleave, final int majorInterleave,
 				final double absoluteScale) {
 			if (interleave * absoluteScale > MIN_ABSOLUTE_INTERLEAVE) {
 				return interleave;
 			}

 			if (medInterleave * absoluteScale > MIN_ABSOLUTE_INTERLEAVE) {
 				return medInterleave;
 			}

 			if (majorInterleave * absoluteScale > MIN_ABSOLUTE_INTERLEAVE) {
 				return majorInterleave;
 			}
 			return -1;
 		}

 		private static int getLineStart(final int origin, final int clip, final int distance) {
 			int newOrigin = origin;
 			if (origin >= clip) {
 				while (newOrigin - distance >= clip) {
 					newOrigin -= distance;
 				}
 			} else {
 				while (newOrigin < clip) {
 					newOrigin += distance;
 				}
 			}
 			return newOrigin;
 		}

 		private static void setLineStyle(final Graphics g, final int currLinePos, final int origin,
 				final int majorInterleave, final int mediumInterleave) {
 			final int delta = origin - currLinePos;
 			if (0 == (delta % majorInterleave)) {
 				g.setLineDash(GRID_MAJOR_DASHES_STYLE);
 			} else if (0 == (delta % mediumInterleave)) {
 				g.setLineDash(GRID_MEDIUM_DASHES_STYLE);
 			} else {
 				g.setLineDash(GRID_MINOR_DASHES_STYLE);
 			}
 		}

 	}

 	/**
 	 * MarqueeDragTracker which deselects all elements on right click if nothing so
 	 * that the correct conext menu is shown. We are only here if there is no
 	 * element under the cursor.
 	 *
 	 * Furthermore it performs autoscrolling if the user went beyond the viewport
 	 * boundaries.
 	 */
 	public class AdvancedMarqueeDragTracker extends MarqueeDragTracker {
 		@Override
 		protected boolean handleButtonDown(final int button) {
 			if (3 == button) {
 				// on right click deselect everything
 				getViewer().setSelection(StructuredSelection.EMPTY);
 			}
 			return super.handleButtonDown(button);
 		}

 		@Override
 		public void mouseDown(final MouseEvent me, final EditPartViewer viewer) {
 			if (viewer instanceof AdvancedScrollingGraphicalViewer) {
 				bindToContentPane(me, (AdvancedScrollingGraphicalViewer) viewer);
 			}
 			super.mouseDown(me, viewer);
 		}

 		@Override
 		public void mouseDrag(final MouseEvent me, final EditPartViewer viewer) {
 			if (isActive() && viewer instanceof AdvancedScrollingGraphicalViewer) {
 				final Point oldViewPort = ((AdvancedScrollingGraphicalViewer) viewer).getViewLocation();
 				((AdvancedScrollingGraphicalViewer) viewer).checkScrollPositionDuringDrag(me);
 				final Dimension delta = oldViewPort
 						.getDifference(((AdvancedScrollingGraphicalViewer) viewer).getViewLocation());
 				// Compensate the moved scrolling in the start position for correct dropping of
 				// moved parts
 				setStartLocation(getStartLocation().getTranslated(delta));
 				bindToContentPane(me, (AdvancedScrollingGraphicalViewer) viewer);
 			}
 			super.mouseDrag(me, viewer);
 		}

 		protected void bindToContentPane(final MouseEvent me, final AdvancedScrollingGraphicalViewer viewer) {
 			final Rectangle contentPaneBounds = viewer.translateBoundsToRoute(
 					((FreeformGraphicalRootEditPart) viewer.getRootEditPart()).getContentPane());

 			final org.eclipse.draw2d.geometry.Point viewLocation = viewer.getViewLocation();
 			me.x += viewLocation.x;
 			me.y += viewLocation.y;

 			me.x = Math.max(me.x, contentPaneBounds.getTopLeft().x);
 			me.y = Math.max(me.y, contentPaneBounds.getTopLeft().y);

 			me.x = Math.min(me.x, contentPaneBounds.getBottomRight().x - 1);
 			me.y = Math.min(me.y, contentPaneBounds.getBottomRight().y - 1);
 			me.x -= viewLocation.x;
 			me.y -= viewLocation.y;
 		}

 		@Override
 		protected boolean handleDoubleClick(final int button) {
 			if (1 == button) {
 				performOpen();
 			}
 			return true;
 		}

 		protected void performOpen() {
 			final EditPart editPart = getCurrentViewer().findObjectAt(getLocation());
 			if (null != editPart) {
 				final SelectionRequest request = new SelectionRequest();
 				request.setLocation(getLocation());
 				request.setType(RequestConstants.REQ_OPEN);
 				editPart.performRequest(request);
 			}
 		}

 	}

 	public static final String TOP_LAYER = "TOPLAYER"; //$NON-NLS-1$

 	public ZoomScalableFreeformRootEditPart(final IWorkbenchPartSite site, final ActionRegistry actionRegistry) {
 		configureZoomManger();
 		setupZoomActions(site, actionRegistry);
 	}

 	@Override
 	public DragTracker getDragTracker(final Request req) {
 		return new AdvancedMarqueeDragTracker();
 	}

 	@Override
 	protected LayeredPane createPrintableLayers() {
 		final FreeformLayeredPane layeredPane = new FreeformLayeredPane();
 		layeredPane.add(new FreeformLayer(), PRIMARY_LAYER);
 		final ConnectionLayer connectionLayer = new ConnectionLayer();
 		layeredPane.add(connectionLayer, CONNECTION_LAYER);

 		final FreeformLayer topLayer = new FreeformLayer();
 		topLayer.setLayoutManager(new FreeformLayout());
 		layeredPane.add(topLayer, TOP_LAYER);
 		return layeredPane;
 	}

 	@Override
 	protected GridLayer createGridLayer() {
 		return new MajorMinorGridLayer();
 	}

 	// Duplicated and adjusted this method from base class to allow moving the
 	// handle_layer and feedback_layer to scaled layers for correct zooming
 	@Override
 	protected void createLayers(final LayeredPane layeredPane) {
 		layeredPane.add(getScaledLayers(), SCALABLE_LAYERS);
 		layeredPane.add(new GuideLayer(), GUIDE_LAYER);
 	}

 	private static class FeedbackLayer extends FreeformLayer {
 		FeedbackLayer() {
 			setEnabled(false);
 		}
 	}

 	@Override
 	protected ScalableFreeformLayeredPane createScaledLayers() {
 		final ScalableFreeformLayeredPane pane = super.createScaledLayers();
 		pane.add(new FreeformLayer(), HANDLE_LAYER);
 		pane.add(new FeedbackLayer(), FEEDBACK_LAYER);
 		return pane;
 	}

 	private void configureZoomManger() {
 		final List<String> zoomLevels = new ArrayList<>(3);
 		zoomLevels.add(ZoomManager.FIT_ALL);
 		zoomLevels.add(ZoomManager.FIT_WIDTH);
 		zoomLevels.add(ZoomManager.FIT_HEIGHT);
 		getZoomManager().setZoomLevelContributions(zoomLevels);
 		getZoomManager().setZoomLevels(new double[] { .25, .5, .75, .80, .85, .90, 1.0, 1.5, 2.0, 2.5, 3, 4 });
 		getZoomManager().setZoomAnimationStyle(ZoomManager.ANIMATE_ZOOM_IN_OUT);
 	}

 	private void setupZoomActions(final IWorkbenchPartSite site, final ActionRegistry actionRegistry) {
 		final IAction zoomIn = new ZoomInAction(getZoomManager());
 		final IAction zoomOut = new ZoomOutAction(getZoomManager());
 		actionRegistry.registerAction(zoomIn);
 		actionRegistry.registerAction(zoomOut);

 		final IHandlerService zoomInService = site.getService(IHandlerService.class);
 		zoomInService.activateHandler(zoomIn.getActionDefinitionId(), new ActionHandler(zoomIn));

 		final IHandlerService zoomOutService = site.getService(IHandlerService.class);
 		zoomOutService.activateHandler(zoomOut.getActionDefinitionId(), new ActionHandler(zoomOut));

 	}

 	@Override
 	protected ZoomManager createZoomManager(final ScalableFigure scalableFigure, final Viewport viewport) {
 		return new AdvancedZoomManager(scalableFigure, viewport);
 	}

 	@Override
 	protected IFigure createFigure() {
 		final FreeformViewport viewPort = (FreeformViewport) super.createFigure();
 		final FreeformLayeredPane drawingArea = (FreeformLayeredPane) viewPort.getContents();

 		final BackgroundFreeformFigure editorBackground = new BackgroundFreeformFigure();
 		viewPort.setContents(editorBackground);
 		final ModuloFreeformFigure drawingAreaContainer = new ModuloFreeformFigure(); // same size as drawingArea,
 		// resizes that
 		drawingAreaContainer.setBorder(new SingleLineBorder());
 		editorBackground.setContents(drawingAreaContainer);
 		drawingAreaContainer.setContents(drawingArea);

 		return viewPort;
 	}

 	protected class ModuloFreeformFigure extends Figure implements FreeformFigure, FreeformListener {
 		private FreeformLayeredPane contents;
 		private Rectangle extent;

 		private static final int PADDING = 0;
 		private static final int BASE_WIDTH = 400;
 		private static final int BASE_HEIGHT = 200;

 		ModuloFreeformFigure() {
 			setOpaque(true);

 			final ColorRegistry colorRegistry = PlatformUI.getWorkbench().getThemeManager().getCurrentTheme()
 					.getColorRegistry();

 			setBackgroundColor(colorRegistry.get("org.eclipse.ui.editors.backgroundColor")); //$NON-NLS-1$

 		}

 		@Override
 		public void addFreeformListener(final FreeformListener listener) {
 			addListener(FreeformListener.class, listener);
 		}

 		@Override
 		public void fireExtentChanged() {
 			performRevalidation();
 		}

 		@Override
 		public void notifyFreeformExtentChanged() {
 			performRevalidation();
 		}

 		@Override
 		public Rectangle getFreeformExtent() {
 			if (extent == null) {
 				extent = calculateModuloExtent();
 				translateToParent(extent);
 			}
 			return extent;
 		}

 		private Rectangle calculateModuloExtent() { // adjust size to be a multiple of the base width/height
 			Rectangle contentsExtent = getUnscaledContentsExtent();
 			contentsExtent.shrink(getInsets());  // take any border into our calculation
 			final int x = calcAxisOrigin(contentsExtent.x, BASE_WIDTH);
 			final int y = calcAxisOrigin(contentsExtent.y, BASE_HEIGHT);
 			final int width = calcAxisExtent(contentsExtent.x, x, contentsExtent.width, BASE_WIDTH);
 			final int height = calcAxisExtent(contentsExtent.y, y, contentsExtent.height, BASE_HEIGHT);
 			contentsExtent = new Rectangle(x, y, width, height);
 			contentsExtent.scale(getZoomManager().getZoom());
 			return contentsExtent;
 		}

 		private Rectangle getUnscaledContentsExtent() {
 			final Rectangle contentsExtent = ((FreeformFigure) getContentPane()).getFreeformExtent().getCopy();
 			// add handle and feedback layer so that dragging elements result in growing the modulo extend
 			contentsExtent.union(((FreeformFigure) getLayer(HANDLE_LAYER)).getFreeformExtent());
 			contentsExtent.union(((FreeformFigure) getLayer(FEEDBACK_LAYER)).getFreeformExtent());
 			return contentsExtent;
 		}

 		private int calcAxisExtent(final int baseOrigin, final int newOrigin, final int sourceExtent,
 				final int baseUnit) {
 			final int startExtent = sourceExtent + PADDING + baseOrigin - newOrigin;

 			int newExtend = (startExtent / baseUnit + 1) * baseUnit;
 			if (newExtend < (3 * baseUnit)) {
 				newExtend = 3 * baseUnit;
 			}
 			return newExtend;
 		}

 		private int calcAxisOrigin(final int axisPos, final int baseUnit) {
 			if (axisPos < 0) {
 				// when negative we need to go one beyond to have the correct origin
 				return (axisPos / baseUnit - 1) * baseUnit;
 			}
 			return (axisPos / baseUnit) * baseUnit;
 		}

 		private void performRevalidation() { // see invalidate() from FreeformHelper
 			extent = null;
 			if (getParent() != null) {
 				((BackgroundFreeformFigure) getParent()).performRevalidation();
 			} else {
 				revalidate();
 			}
 		}

 		@Override
 		public void removeFreeformListener(final FreeformListener listener) {
 			removeListener(FreeformListener.class, listener);
 		}

 		@Override
 		public void setFreeformBounds(final Rectangle bounds) {
 			Rectangle r = getFreeformExtent(); // we insist on our own size calculation
 			setBounds(r);
 			r = r.getCopy();
 			translateFromParent(r);
 			contents.setFreeformBounds(r);
 		}

 		public void setContents(final FreeformLayeredPane contents) {
 			this.contents = contents;
 			add(contents);
 			contents.addFreeformListener(this);
 		}
 	}

 	protected class BackgroundFreeformFigure extends Figure implements FreeformFigure, FreeformListener {
 		private ModuloFreeformFigure contents;
 		private Rectangle extent;

 		public BackgroundFreeformFigure() {
 			setOpaque(true);
 			final Display display = Display.getCurrent();
 			if (null != display) {
 				setBackgroundColor(display.getSystemColor(SWT.COLOR_WIDGET_BACKGROUND));
 			}
 		}

 		@Override
 		public void addFreeformListener(final FreeformListener listener) {
 			addListener(FreeformListener.class, listener);
 		}

 		@Override
 		public void fireExtentChanged() {
 			getListeners(FreeformListener.class)
 			.forEachRemaining(listener -> ((FreeformListener) listener).notifyFreeformExtentChanged());
 			performRevalidation();
 		}

 		@Override
 		public void notifyFreeformExtentChanged() {
 			performRevalidation();
 		}

 		@Override
 		public Rectangle getFreeformExtent() {
 			if (extent == null) {
 				extent = contents.getFreeformExtent().getCopy();
 				final FigureCanvas figureCanvas = (FigureCanvas) getViewer().getControl();
 				final org.eclipse.swt.graphics.Rectangle canvasBounds = figureCanvas.getBounds();
 				extent.expand(canvasBounds.width * 0.9, canvasBounds.height * 0.9);
 				translateToParent(extent);
 			}
 			return extent;
 		}

 		@Override
 		public void removeFreeformListener(final FreeformListener listener) {
 			removeListener(FreeformListener.class, listener);
 		}

 		@Override
 		public void setFreeformBounds(final Rectangle bounds) {
 			final Rectangle newExtents = calculateBackgroundSize(bounds);
 			setBounds(newExtents);
 			translateFromParent(newExtents);
 			contents.setFreeformBounds(newExtents); // we insist on our own size calculation
 		}

 		private Rectangle calculateBackgroundSize(final Rectangle bounds) {
 			return new Rectangle(bounds.x + ((bounds.width - extent.width) / 2),
 					bounds.y + ((bounds.height - extent.height) / 2), extent.width, extent.height);
 		}

 		public void setContents(final ModuloFreeformFigure contents) {
 			this.contents = contents;
 			add(contents);
 			contents.addFreeformListener(this);
 		}

 		private void performRevalidation() { // see invalidate() from FreeformHelper
 			extent = null;
 			if (getParent() != null) {
 				getParent().revalidate();
 			} else {
 				revalidate();
 			}
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2008, 2021 Profactor GbmH, fortiss GmbH, Johannes Kepler University
	*
	* This program and the accompanying materials are made available under the
	* terms of the Eclipse Public License 2.0 which is available at
	* http://www.eclipse.org/legal/epl-2.0.
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* Gerhard Ebenhofer, Alois Zoitl
	* - initial API and implementation and/or initial documentation
	* Alois Zoitl - Changed grid layer so that it shows every 10th and 5th line
	* emphasized
	* - added autoscroll to marquee drag tracker
	* - moved incremental growing canvas from FBNetworkRootEditPart to
	* here so that all graphical editors can have it
	*******************************************************************************/
	package org.eclipse.fordiac.ide.gef.editparts;

	import java.util.ArrayList;
	import java.util.List;

	import org.eclipse.draw2d.ConnectionLayer;
	import org.eclipse.draw2d.Figure;
	import org.eclipse.draw2d.FigureCanvas;
	import org.eclipse.draw2d.FreeformFigure;
	import org.eclipse.draw2d.FreeformLayer;
	import org.eclipse.draw2d.FreeformLayeredPane;
	import org.eclipse.draw2d.FreeformLayout;
	import org.eclipse.draw2d.FreeformListener;
	import org.eclipse.draw2d.FreeformViewport;
	import org.eclipse.draw2d.Graphics;
	import org.eclipse.draw2d.IFigure;
	import org.eclipse.draw2d.LayeredPane;
	import org.eclipse.draw2d.ScalableFigure;
	import org.eclipse.draw2d.ScalableFreeformLayeredPane;
	import org.eclipse.draw2d.Viewport;
	import org.eclipse.draw2d.geometry.Dimension;
	import org.eclipse.draw2d.geometry.Point;
	import org.eclipse.draw2d.geometry.Rectangle;
	import org.eclipse.fordiac.ide.gef.draw2d.SingleLineBorder;
	import org.eclipse.fordiac.ide.model.ui.editors.AdvancedScrollingGraphicalViewer;
	import org.eclipse.gef.DragTracker;
	import org.eclipse.gef.EditPart;
	import org.eclipse.gef.EditPartViewer;
	import org.eclipse.gef.Request;
	import org.eclipse.gef.RequestConstants;
	import org.eclipse.gef.editparts.FreeformGraphicalRootEditPart;
	import org.eclipse.gef.editparts.GridLayer;
	import org.eclipse.gef.editparts.GuideLayer;
	import org.eclipse.gef.editparts.ScalableFreeformRootEditPart;
	import org.eclipse.gef.editparts.ZoomManager;
	import org.eclipse.gef.requests.SelectionRequest;
	import org.eclipse.gef.tools.MarqueeDragTracker;
	import org.eclipse.gef.ui.actions.ActionRegistry;
	import org.eclipse.gef.ui.actions.ZoomInAction;
	import org.eclipse.gef.ui.actions.ZoomOutAction;
	import org.eclipse.jface.action.IAction;
	import org.eclipse.jface.commands.ActionHandler;
	import org.eclipse.jface.resource.ColorRegistry;
	import org.eclipse.jface.viewers.StructuredSelection;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.MouseEvent;
	import org.eclipse.swt.widgets.Display;
	import org.eclipse.ui.IWorkbenchPartSite;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.handlers.IHandlerService;

	public class ZoomScalableFreeformRootEditPart extends ScalableFreeformRootEditPart {

	/**
	* Grid layer that draws the grid in dashed lines and every X line solid to give
	* the grid more structure
	*/
	private static class MajorMinorGridLayer extends GridLayer {
	private static final double MIN_ABSOLUTE_INTERLEAVE = 5.0;

	private static final int MAJOR_INTERLEAVE = 10; // draw each 10th line thicker dashed to give the grid more
	// structure
	private static final int MEDIUM_INTERLEAVE = 5; // draw each 5th line medium dashed to give the grid more
	// structure

	private static final float[] GRID_MINOR_DASHES_STYLE = new float[] { 1.0f, 5.0f };
	private static final float[] GRID_MEDIUM_DASHES_STYLE = new float[] { 2.0f, 4.0f };
	private static final float[] GRID_MAJOR_DASHES_STYLE = new float[] { 4.0f, 2.0f };

	@Override
	protected void paintGrid(final Graphics g) {
	final int origLineStyle = g.getLineStyle();
	g.setLineStyle(Graphics.LINE_CUSTOM);

	final Rectangle clip = g.getClip(Rectangle.SINGLETON);

	if (gridX > 0) {
	drawVerLines(g, clip);
	}

	if (gridY > 0) {
	drawHorLines(g, clip);
	}
	g.setLineStyle(origLineStyle);
	}

	private void drawVerLines(final Graphics g, final Rectangle clip) {
	final int majorInterleaveX = gridX * MAJOR_INTERLEAVE;
	final int medInterleaveX = gridX * MEDIUM_INTERLEAVE;
	final int realInterleaveX = determineInterleave(gridX, medInterleaveX, majorInterleaveX, g.getAbsoluteScale());

	if (realInterleaveX > 0) {
	for (int i = getLineStart(origin.x, clip.x, realInterleaveX); i < clip.x
	+ clip.width; i += realInterleaveX) {
	setLineStyle(g, i, origin.x, majorInterleaveX, medInterleaveX);
	g.drawLine(i, clip.y, i, clip.y + clip.height);
	}
	}
	}

	private void drawHorLines(final Graphics g, final Rectangle clip) {
	final int majorInterleaveY = gridY * MAJOR_INTERLEAVE;
	final int medInterleaveY = gridY * MEDIUM_INTERLEAVE;
	final int realInterleaveY = determineInterleave(gridY, medInterleaveY, majorInterleaveY, g.getAbsoluteScale());
	if (realInterleaveY > 0) {
	for (int i = getLineStart(origin.y, clip.y, realInterleaveY); i < clip.y
	+ clip.height; i += realInterleaveY) {
	setLineStyle(g, i, origin.y, majorInterleaveY, medInterleaveY);
	g.drawLine(clip.x, i, clip.x + clip.width, i);
	}
	}
	}

	private static int determineInterleave(final int interleave, final int medInterleave, final int majorInterleave,
	final double absoluteScale) {
	if (interleave * absoluteScale > MIN_ABSOLUTE_INTERLEAVE) {
	return interleave;
	}

	if (medInterleave * absoluteScale > MIN_ABSOLUTE_INTERLEAVE) {
	return medInterleave;
	}

	if (majorInterleave * absoluteScale > MIN_ABSOLUTE_INTERLEAVE) {
	return majorInterleave;
	}
	return -1;
	}

	private static int getLineStart(final int origin, final int clip, final int distance) {
	int newOrigin = origin;
	if (origin >= clip) {
	while (newOrigin - distance >= clip) {
	newOrigin -= distance;
	}
	} else {
	while (newOrigin < clip) {
	newOrigin += distance;
	}
	}
	return newOrigin;
	}

	private static void setLineStyle(final Graphics g, final int currLinePos, final int origin,
	final int majorInterleave, final int mediumInterleave) {
	final int delta = origin - currLinePos;
	if (0 == (delta % majorInterleave)) {
	g.setLineDash(GRID_MAJOR_DASHES_STYLE);
	} else if (0 == (delta % mediumInterleave)) {
	g.setLineDash(GRID_MEDIUM_DASHES_STYLE);
	} else {
	g.setLineDash(GRID_MINOR_DASHES_STYLE);
	}
	}

	}

	/**
	* MarqueeDragTracker which deselects all elements on right click if nothing so
	* that the correct conext menu is shown. We are only here if there is no
	* element under the cursor.
	*
	* Furthermore it performs autoscrolling if the user went beyond the viewport
	* boundaries.
	*/
	public class AdvancedMarqueeDragTracker extends MarqueeDragTracker {
	@Override
	protected boolean handleButtonDown(final int button) {
	if (3 == button) {
	// on right click deselect everything
	getViewer().setSelection(StructuredSelection.EMPTY);
	}
	return super.handleButtonDown(button);
	}

	@Override
	public void mouseDown(final MouseEvent me, final EditPartViewer viewer) {
	if (viewer instanceof AdvancedScrollingGraphicalViewer) {
	bindToContentPane(me, (AdvancedScrollingGraphicalViewer) viewer);
	}
	super.mouseDown(me, viewer);
	}

	@Override
	public void mouseDrag(final MouseEvent me, final EditPartViewer viewer) {
	if (isActive() && viewer instanceof AdvancedScrollingGraphicalViewer) {
	final Point oldViewPort = ((AdvancedScrollingGraphicalViewer) viewer).getViewLocation();
	((AdvancedScrollingGraphicalViewer) viewer).checkScrollPositionDuringDrag(me);
	final Dimension delta = oldViewPort
	.getDifference(((AdvancedScrollingGraphicalViewer) viewer).getViewLocation());
	// Compensate the moved scrolling in the start position for correct dropping of
	// moved parts
	setStartLocation(getStartLocation().getTranslated(delta));
	bindToContentPane(me, (AdvancedScrollingGraphicalViewer) viewer);
	}
	super.mouseDrag(me, viewer);
	}

	protected void bindToContentPane(final MouseEvent me, final AdvancedScrollingGraphicalViewer viewer) {
	final Rectangle contentPaneBounds = viewer.translateBoundsToRoute(
	((FreeformGraphicalRootEditPart) viewer.getRootEditPart()).getContentPane());

	final org.eclipse.draw2d.geometry.Point viewLocation = viewer.getViewLocation();
	me.x += viewLocation.x;
	me.y += viewLocation.y;

	me.x = Math.max(me.x, contentPaneBounds.getTopLeft().x);
	me.y = Math.max(me.y, contentPaneBounds.getTopLeft().y);

	me.x = Math.min(me.x, contentPaneBounds.getBottomRight().x - 1);
	me.y = Math.min(me.y, contentPaneBounds.getBottomRight().y - 1);
	me.x -= viewLocation.x;
	me.y -= viewLocation.y;
	}

	@Override
	protected boolean handleDoubleClick(final int button) {
	if (1 == button) {
	performOpen();
	}
	return true;
	}

	protected void performOpen() {
	final EditPart editPart = getCurrentViewer().findObjectAt(getLocation());
	if (null != editPart) {
	final SelectionRequest request = new SelectionRequest();
	request.setLocation(getLocation());
	request.setType(RequestConstants.REQ_OPEN);
	editPart.performRequest(request);
	}
	}

	}

	public static final String TOP_LAYER = "TOPLAYER"; //$NON-NLS-1$

	public ZoomScalableFreeformRootEditPart(final IWorkbenchPartSite site, final ActionRegistry actionRegistry) {
	configureZoomManger();
	setupZoomActions(site, actionRegistry);
	}

	@Override
	public DragTracker getDragTracker(final Request req) {
	return new AdvancedMarqueeDragTracker();
	}

	@Override
	protected LayeredPane createPrintableLayers() {
	final FreeformLayeredPane layeredPane = new FreeformLayeredPane();
	layeredPane.add(new FreeformLayer(), PRIMARY_LAYER);
	final ConnectionLayer connectionLayer = new ConnectionLayer();
	layeredPane.add(connectionLayer, CONNECTION_LAYER);

	final FreeformLayer topLayer = new FreeformLayer();
	topLayer.setLayoutManager(new FreeformLayout());
	layeredPane.add(topLayer, TOP_LAYER);
	return layeredPane;
	}

	@Override
	protected GridLayer createGridLayer() {
	return new MajorMinorGridLayer();
	}

	// Duplicated and adjusted this method from base class to allow moving the
	// handle_layer and feedback_layer to scaled layers for correct zooming
	@Override
	protected void createLayers(final LayeredPane layeredPane) {
	layeredPane.add(getScaledLayers(), SCALABLE_LAYERS);
	layeredPane.add(new GuideLayer(), GUIDE_LAYER);
	}

	private static class FeedbackLayer extends FreeformLayer {
	FeedbackLayer() {
	setEnabled(false);
	}
	}

	@Override
	protected ScalableFreeformLayeredPane createScaledLayers() {
	final ScalableFreeformLayeredPane pane = super.createScaledLayers();
	pane.add(new FreeformLayer(), HANDLE_LAYER);
	pane.add(new FeedbackLayer(), FEEDBACK_LAYER);
	return pane;
	}

	private void configureZoomManger() {
	final List<String> zoomLevels = new ArrayList<>(3);
	zoomLevels.add(ZoomManager.FIT_ALL);
	zoomLevels.add(ZoomManager.FIT_WIDTH);
	zoomLevels.add(ZoomManager.FIT_HEIGHT);
	getZoomManager().setZoomLevelContributions(zoomLevels);
	getZoomManager().setZoomLevels(new double[] { .25, .5, .75, .80, .85, .90, 1.0, 1.5, 2.0, 2.5, 3, 4 });
	getZoomManager().setZoomAnimationStyle(ZoomManager.ANIMATE_ZOOM_IN_OUT);
	}

	private void setupZoomActions(final IWorkbenchPartSite site, final ActionRegistry actionRegistry) {
	final IAction zoomIn = new ZoomInAction(getZoomManager());
	final IAction zoomOut = new ZoomOutAction(getZoomManager());
	actionRegistry.registerAction(zoomIn);
	actionRegistry.registerAction(zoomOut);

	final IHandlerService zoomInService = site.getService(IHandlerService.class);
	zoomInService.activateHandler(zoomIn.getActionDefinitionId(), new ActionHandler(zoomIn));

	final IHandlerService zoomOutService = site.getService(IHandlerService.class);
	zoomOutService.activateHandler(zoomOut.getActionDefinitionId(), new ActionHandler(zoomOut));

	}

	@Override
	protected ZoomManager createZoomManager(final ScalableFigure scalableFigure, final Viewport viewport) {
	return new AdvancedZoomManager(scalableFigure, viewport);
	}

	@Override
	protected IFigure createFigure() {
	final FreeformViewport viewPort = (FreeformViewport) super.createFigure();
	final FreeformLayeredPane drawingArea = (FreeformLayeredPane) viewPort.getContents();

	final BackgroundFreeformFigure editorBackground = new BackgroundFreeformFigure();
	viewPort.setContents(editorBackground);
	final ModuloFreeformFigure drawingAreaContainer = new ModuloFreeformFigure(); // same size as drawingArea,
	// resizes that
	drawingAreaContainer.setBorder(new SingleLineBorder());
	editorBackground.setContents(drawingAreaContainer);
	drawingAreaContainer.setContents(drawingArea);

	return viewPort;
	}

	protected class ModuloFreeformFigure extends Figure implements FreeformFigure, FreeformListener {
	private FreeformLayeredPane contents;
	private Rectangle extent;

	private static final int PADDING = 0;
	private static final int BASE_WIDTH = 400;
	private static final int BASE_HEIGHT = 200;

	ModuloFreeformFigure() {
	setOpaque(true);

	final ColorRegistry colorRegistry = PlatformUI.getWorkbench().getThemeManager().getCurrentTheme()
	.getColorRegistry();

	setBackgroundColor(colorRegistry.get("org.eclipse.ui.editors.backgroundColor")); //$NON-NLS-1$

	}

	@Override
	public void addFreeformListener(final FreeformListener listener) {
	addListener(FreeformListener.class, listener);
	}

	@Override
	public void fireExtentChanged() {
	performRevalidation();
	}

	@Override
	public void notifyFreeformExtentChanged() {
	performRevalidation();
	}

	@Override
	public Rectangle getFreeformExtent() {
	if (extent == null) {
	extent = calculateModuloExtent();
	translateToParent(extent);
	}
	return extent;
	}

	private Rectangle calculateModuloExtent() { // adjust size to be a multiple of the base width/height
	Rectangle contentsExtent = getUnscaledContentsExtent();
	contentsExtent.shrink(getInsets()); // take any border into our calculation
	final int x = calcAxisOrigin(contentsExtent.x, BASE_WIDTH);
	final int y = calcAxisOrigin(contentsExtent.y, BASE_HEIGHT);
	final int width = calcAxisExtent(contentsExtent.x, x, contentsExtent.width, BASE_WIDTH);
	final int height = calcAxisExtent(contentsExtent.y, y, contentsExtent.height, BASE_HEIGHT);
	contentsExtent = new Rectangle(x, y, width, height);
	contentsExtent.scale(getZoomManager().getZoom());
	return contentsExtent;
	}

	private Rectangle getUnscaledContentsExtent() {
	final Rectangle contentsExtent = ((FreeformFigure) getContentPane()).getFreeformExtent().getCopy();
	// add handle and feedback layer so that dragging elements result in growing the modulo extend
	contentsExtent.union(((FreeformFigure) getLayer(HANDLE_LAYER)).getFreeformExtent());
	contentsExtent.union(((FreeformFigure) getLayer(FEEDBACK_LAYER)).getFreeformExtent());
	return contentsExtent;
	}

	private int calcAxisExtent(final int baseOrigin, final int newOrigin, final int sourceExtent,
	final int baseUnit) {
	final int startExtent = sourceExtent + PADDING + baseOrigin - newOrigin;

	int newExtend = (startExtent / baseUnit + 1) * baseUnit;
	if (newExtend < (3 * baseUnit)) {
	newExtend = 3 * baseUnit;
	}
	return newExtend;
	}

	private int calcAxisOrigin(final int axisPos, final int baseUnit) {
	if (axisPos < 0) {
	// when negative we need to go one beyond to have the correct origin
	return (axisPos / baseUnit - 1) * baseUnit;
	}
	return (axisPos / baseUnit) * baseUnit;
	}

	private void performRevalidation() { // see invalidate() from FreeformHelper
	extent = null;
	if (getParent() != null) {
	((BackgroundFreeformFigure) getParent()).performRevalidation();
	} else {
	revalidate();
	}
	}

	@Override
	public void removeFreeformListener(final FreeformListener listener) {
	removeListener(FreeformListener.class, listener);
	}

	@Override
	public void setFreeformBounds(final Rectangle bounds) {
	Rectangle r = getFreeformExtent(); // we insist on our own size calculation
	setBounds(r);
	r = r.getCopy();
	translateFromParent(r);
	contents.setFreeformBounds(r);
	}

	public void setContents(final FreeformLayeredPane contents) {
	this.contents = contents;
	add(contents);
	contents.addFreeformListener(this);
	}
	}

	protected class BackgroundFreeformFigure extends Figure implements FreeformFigure, FreeformListener {
	private ModuloFreeformFigure contents;
	private Rectangle extent;

	public BackgroundFreeformFigure() {
	setOpaque(true);
	final Display display = Display.getCurrent();
	if (null != display) {
	setBackgroundColor(display.getSystemColor(SWT.COLOR_WIDGET_BACKGROUND));
	}
	}

	@Override
	public void addFreeformListener(final FreeformListener listener) {
	addListener(FreeformListener.class, listener);
	}

	@Override
	public void fireExtentChanged() {
	getListeners(FreeformListener.class)
	.forEachRemaining(listener -> ((FreeformListener) listener).notifyFreeformExtentChanged());
	performRevalidation();
	}

	@Override
	public void notifyFreeformExtentChanged() {
	performRevalidation();
	}

	@Override
	public Rectangle getFreeformExtent() {
	if (extent == null) {
	extent = contents.getFreeformExtent().getCopy();
	final FigureCanvas figureCanvas = (FigureCanvas) getViewer().getControl();
	final org.eclipse.swt.graphics.Rectangle canvasBounds = figureCanvas.getBounds();
	extent.expand(canvasBounds.width * 0.9, canvasBounds.height * 0.9);
	translateToParent(extent);
	}
	return extent;
	}

	@Override
	public void removeFreeformListener(final FreeformListener listener) {
	removeListener(FreeformListener.class, listener);
	}

	@Override
	public void setFreeformBounds(final Rectangle bounds) {
	final Rectangle newExtents = calculateBackgroundSize(bounds);
	setBounds(newExtents);
	translateFromParent(newExtents);
	contents.setFreeformBounds(newExtents); // we insist on our own size calculation
	}

	private Rectangle calculateBackgroundSize(final Rectangle bounds) {
	return new Rectangle(bounds.x + ((bounds.width - extent.width) / 2),
	bounds.y + ((bounds.height - extent.height) / 2), extent.width, extent.height);
	}

	public void setContents(final ModuloFreeformFigure contents) {
	this.contents = contents;
	add(contents);
	contents.addFreeformListener(this);
	}

	private void performRevalidation() { // see invalidate() from FreeformHelper
	extent = null;
	if (getParent() != null) {
	getParent().revalidate();
	} else {
	revalidate();
	}
	}
	}
	}