com.smartgwt.client.widgets.drawing

## Class DrawPane

- java.lang.Object
- - com.google.gwt.user.client.ui.UIObject
  - - com.google.gwt.user.client.ui.Widget
    - - com.smartgwt.client.widgets.BaseWidget
      - - com.smartgwt.client.widgets.Canvas
        - - com.smartgwt.client.widgets.drawing.DrawPane

- All Implemented Interfaces:
    com.google.gwt.event.logical.shared.HasAttachHandlers, com.google.gwt.event.shared.HasHandlers, com.google.gwt.user.client.EventListener, com.google.gwt.user.client.ui.HasVisibility, com.google.gwt.user.client.ui.IsWidget, LogicalStructure, HasClickHandlers, HasDoubleClickHandlers, HasDragMoveHandlers, HasDragRepositionMoveHandlers, HasDragRepositionStartHandlers, HasDragRepositionStopHandlers, HasDragResizeMoveHandlers, HasDragResizeStartHandlers, HasDragResizeStopHandlers, HasDragStartHandlers, HasDragStopHandlers, HasDropHandlers, HasDropMoveHandlers, HasDropOutHandlers, HasDropOverHandlers, HasFocusChangedHandlers, HasHoverHandlers, HasHoverHiddenHandlers, HasKeyDownHandlers, HasKeyPressHandlers, HasMouseDownHandlers, HasMouseMoveHandlers, HasMouseOutHandlers, HasMouseOverHandlers, HasMouseStillDownHandlers, HasMouseUpHandlers, HasMouseWheelHandlers, HasMovedHandlers, HasParentMovedHandlers, HasResizedHandlers, HasRightMouseDownHandlers, HasScrolledHandlers, HasShowContextMenuHandlers, HasVisibilityChangedHandlers
  Direct Known Subclasses:
    FacetChart, Gauge

      public class DrawPane
      extends Canvas

  A DrawPane is a container for drawing bitmap and vector graphics using browser's built-in freeform drawing capabilities. These include the HTML5 `<canvas>` tag and `SVG (Scalable Vector Graphics)` where available, and the `VML (Vector Markup Language)` for legacy browsers (Internet Explorer 8 and earlier).

  To draw in a `DrawPane` you create `DrawLine`s, `DrawOval`s, `DrawPath`s and other `DrawItem`-based components, and place them in the `DrawPane` via `drawItems` or add them incrementally via `DrawPane.addDrawItem()`.

  `DrawItems` support a variety of common features, such as `gradient fills`, `arrowheads`, events such as `click()` and built-in `control knobs` for end user resizing and manipulation of shapes.

  Common shapes such as `rectangles`, `ovals` and `triangles` have dedicated DrawItem subclasses. For other shapes, consider:

  - `DrawPath` - a multi-segment line with straight segments, defined by a series of `points`
  - `DrawPolygon` - a closed shape with straight sides, defined by a series of `points`
  - `DrawShape` - a multi-segment line or closed shape whose sides can be defined by a series of commands, including curved arcs

  NOTE:To use the Drawing subsystem, include the Drawing module in your application by including `<inherits name="com.smartgwt.Drawing"/>` in your GWT module XML.

  ### Note on Coordinate Systems

  There are three different coordinate systems involved when a DrawItem is drawn onto a DrawPane:
  - The "local coordinate system" for a DrawItem refers to the Cartesian coordinate system in which dimensional and positional values are interpreted. For example, when a `DrawRect` is configured with left:20, top:30, width:200, and height:100, the DrawRect represents a rectangle from (20, 30) to (220, 130) in its local coordinate system.

    There is a local coordinate system for each DrawItem.

  - The "drawing coordinate system" refers to the Cartesian coordinate system shared by all DrawItems after their local transforms, such as `scale` or `rotation`, have been applied.

    For DrawItems with no local transforms, the drawing coordinate system is identical to the local coordinate system.

  - The "global coordinate system" refers to the drawing coordinate system with global DrawPane transforms `translate`, `zoomLevel` and `rotation` applied.

    With the default global transforms, the global coordinate system is identical to the drawing coordinate system.

  The view port of the DrawPane is the rectangle in the global coordinate system from (0, 0) that is as wide as the DrawPane's `inner content width` and as high as the DrawPane's `inner content height`. Note: In the case of a `FacetChart` showing a `zoom chart`, the view port height is decreased by the height of the zoom chart.

  One other coordinate system in use by a DrawPane when `drag-scrolling` is enabled is the "viewbox coordinate system". The viewbox coordinate system is the drawing coordinate system with the `translate` and `zoomLevel` transforms applied.

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from class com.google.gwt.user.client.ui.UIObject

      `com.google.gwt.user.client.ui.UIObject.DebugIdImpl, com.google.gwt.user.client.ui.UIObject.DebugIdImplEnabled`

  - ### Field Summary

    - ### Fields inherited from class com.smartgwt.client.widgets.BaseWidget

      `config, configOnly, factoryCreated, factoryProperties, id, nativeObject, scClassName`

    - ### Fields inherited from class com.google.gwt.user.client.ui.UIObject

      `DEBUG_ID_PREFIX`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `DrawPane()`
    `DrawPane(com.google.gwt.core.client.JavaScriptObject jsObj)`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `addDrawItem(DrawItem item, boolean autoDraw)` Add a drawItem to this drawPane (if necessary removing it from any other drawPanes)
    `java.lang.String` | `addGradient(Gradient gradient)` Add a new gradient to the drawPane shared gradient list (`gradients`).
    `static double` | `bezier(double p1, double cp1, double cp2, double p2, double t)` Computes a cubic Bézier curve polynomial: `B(t) = (1 - t)3P1 + 3(1 - t)2tCP1 + 3(1 - t)t2CP2 + t3P2`
    `static double[]` | `bezierExtrema(double p1, double cp1, double cp2, double p2)` Computes the minimum and maximum value of the cubic Bézier curve polynomial defined in `DrawPane.bezier()`, for `0 ≤ t ≤ 1`.
    `static void` | `changeAutoChildDefaults(java.lang.String autoChildName, Canvas defaults)` Changes the defaults for Canvas AutoChildren named `autoChildName`.
    `static void` | `changeAutoChildDefaults(java.lang.String autoChildName, FormItem defaults)` Changes the defaults for FormItem AutoChildren named `autoChildName`.
    `protected com.google.gwt.core.client.JavaScriptObject` | `create()`
    `java.lang.String` | `createLinearGradient(java.lang.String id, LinearGradient linearGradient)` Deprecated. in favor of `DrawPane.addGradient()`
    `java.lang.String` | `createRadialGradient(java.lang.String id, RadialGradient radialGradient)` Deprecated. in favor of `DrawPane.addGradient()`
    `java.lang.String` | `createSimpleGradient(java.lang.String id, SimpleGradient simple)` Deprecated. in favor of `DrawPane.addGradient()`
    `void` | `destroyItems()` Permanently `destroy` all DrawItems currently associated with this DrawPane, leaving the DrawPane itself intact
    `void` | `erase()` Call `DrawItem.erase()` on all DrawItems currently associated with the DrawPane.
    `static double[]` | `getBezierBoundingBox(Point p1, Point cp1, Point cp2, Point p2)` Calculate the bounding box of the cubic Bézier curve with endpoints `p1` and `p2` and control points `cp1` and `cp2`.
    `boolean` | `getCanDragScroll()` Can the user drag-scroll the DrawPane?
    `java.lang.String` | `getDataURL()` Get a "data:" URL encoding the current contents of the DrawPane as a PNG file.
    `java.lang.String` | `getDataURL(DataURLCallback callback)` Get a "data:" URL encoding the current contents of the DrawPane as a PNG file.
    `int` | `getDrawingHeight()` When `canDragScroll` is enabled, this is the height of the area in viewbox coordinates that can be accessed through drag-scrolling.
    `int` | `getDrawingWidth()` When `canDragScroll` is enabled, this is the width of the area in viewbox coordinates that can be accessed through drag-scrolling.
    `DrawItem[]` | `getDrawItems()` Array of DrawItems to initially display in this DrawPane.
    `java.lang.String` | `getEditProxyConstructor()` Default class used to construct the `EditProxy` for this component when the component is `first placed into edit mode`.
    `Gradient` | `getGradient(java.lang.String gradientID)` Returns gradient for gradientID.
    `Gradient[]` | `getGradients()` Array of gradients that can be referenced by DrawItems placed on this DrawPane.
    `com.smartgwt.logicalstructure.core.LogicalStructureObject` | `getLogicalStructure()` Getter implementing the `LogicalStructure` interface, which supports Eclipse's logical structure debugging facility.
    `static DrawPane` | `getOrCreateRef(com.google.gwt.core.client.JavaScriptObject jsObj)`
    `static Point[]` | `getPolygonPoints(int width, int height, int xc, int yc, double[] angles)` Computes an array of Points for a polygon that has an equal distance from its center to any of its vertices and that fits in the given width and height.
    `java.lang.String` | `getPrintHTML(PrintProperties printProperties, PrintHTMLCallback callback)` Retrieves printable HTML for this component and all printable subcomponents.
    `static Point[]` | `getRegularPolygonPoints(int n, int width, int height, int xc, int yc, double startAngle)` Calls `DrawPane.getPolygonPoints()` with angles spread evenly over the full 360 degrees.
    `float` | `getRotation()` Deprecated. `GwtFloatVsDouble`
    `double` | `getRotationAsDouble()` Rotation in degrees for the `DrawPane` as a whole about the center of the `DrawPane`.
    `java.lang.String` | `getSvgString()` Converts this DrawPane to the source of an `<svg>` element equivalent to the current drawing.
    `int[]` | `getTranslate()` Global translation.
    `float` | `getZoomLevel()` Deprecated. `GwtFloatVsDouble`
    `double` | `getZoomLevelAsDouble()` Zoom for the `DrawPane` as a whole, where 1 is normal size.
    `void` | `removeGradient(java.lang.String gradientID)` Removes gradient for gradientID.
    `void` | `rotate(double degrees)` Synonym of `DrawPane.setRotation()`.
    `static void` | `scaleAndCenter(int width, int height, int xc, int yc, Point... points)` Computes the top-, left-, bottom-, and right-most coordinates in a list of points, then translates and scales all points to fit the entire shape into the given width and height.
    `static void` | `scaleAndCenterBezier(int width, int height, int xc, int yc, Point startPoint, Point endPoint, Point controlPoint1, Point controlPoint2)` Computes the top-, left-, bottom-, and right-most coordinates containing the Bézier curve defined by `startPoint`, `controlPoint1`, `controlPoint2`, and `endPoint`, then translates and scales these four points to fit the entire curve into the given width and height.
    `void` | `setCanDragScroll(boolean canDragScroll)` Can the user drag-scroll the DrawPane?
    `static void` | `setDefaultProperties(DrawPane drawPaneProperties)` Class level method to set the default properties of this class.
    `void` | `setDrawingHeight(int drawingHeight)` When `canDragScroll` is enabled, this is the height of the area in viewbox coordinates that can be accessed through drag-scrolling.
    `void` | `setDrawingWidth(int drawingWidth)` When `canDragScroll` is enabled, this is the width of the area in viewbox coordinates that can be accessed through drag-scrolling.
    `void` | `setDrawItems(DrawItem... drawItems)` Array of DrawItems to initially display in this DrawPane.
    `void` | `setEditProxyConstructor(java.lang.String editProxyConstructor)` Default class used to construct the `EditProxy` for this component when the component is `first placed into edit mode`.
    `void` | `setGradients(Gradient... gradients)` Array of gradients that can be referenced by DrawItems placed on this DrawPane.
    `com.smartgwt.logicalstructure.core.LogicalStructureObject` | `setLogicalStructure(com.smartgwt.logicalstructure.widgets.drawing.DrawPaneLogicalStructure s)` Setter implementing the `LogicalStructure` interface, which supports Eclipse's logical structure debugging facility.
    `void` | `setRotation(double rotation)` Rotation in degrees for the `DrawPane` as a whole about the center of the `DrawPane`.
    `void` | `setRotation(float rotation)` Deprecated. `GwtFloatVsDouble`
    `void` | `setTranslate(int[] translate)` Global translation.
    `void` | `setZoomLevel(double zoomLevel)` Zoom for the `DrawPane` as a whole, where 1 is normal size.
    `void` | `setZoomLevel(float zoomLevel)` Deprecated. `GwtFloatVsDouble`
    `void` | `zoom(double zoomLevel)` Synonym of `DrawPane.setZoomLevel()`.
    `void` | `zoom(float zoomLevel)` Deprecated. `GwtFloatVsDouble`

    - ### Methods inherited from class com.smartgwt.client.widgets.Canvas

      `addChild, addChild, addChild, addChild, addChild, addClickHandler, addDoubleClickHandler, addDragMoveHandler, addDragRepositionMoveHandler, addDragRepositionStartHandler, addDragRepositionStopHandler, addDragResizeMoveHandler, addDragResizeStartHandler, addDragResizeStopHandler, addDragStartHandler, addDragStopHandler, addDropHandler, addDropMoveHandler, addDropOutHandler, addDropOverHandler, addFocusChangedHandler, addHoverHandler, addHoverHiddenHandler, addKeyDownHandler, addKeyPressHandler, addMouseDownHandler, addMouseMoveHandler, addMouseOutHandler, addMouseOverHandler, addMouseStillDownHandler, addMouseUpHandler, addMouseWheelHandler, addMovedHandler, addParentMovedHandler, addPeer, addPeer, addPeer, addPeer, addResizedHandler, addRightMouseDownHandler, addScrolledHandler, addShowContextMenuHandler, addStyleName, addVisibilityChangedHandler, adjustForContent, animateFade, animateFade, animateFade, animateFade, animateFade, animateFade, animateFade, animateFade, animateHide, animateHide, animateHide, animateMove, animateMove, animateMove, animateMove, animateRect, animateRect, animateRect, animateRect, animateResize, animateResize, animateResize, animateResize, animateScroll, animateScroll, animateScroll, animateScroll, animateScroll, animateScroll, animateShow, animateShow, animateShow, animateShow, animateShow, animateShow, asSGWTComponent, blur, bringToFront, clear, clickMaskUp, clickMaskUp, contains, contains, containsEvent, containsFocus, containsPoint, containsPoint, deparent, depeer, disable, enable, encloses, focus, focusInNextTabElement, focusInPreviousTabElement, getAbsoluteLeft, getAbsoluteTop, getAccessKey, getAlwaysShowScrollbars, getAnimateAcceleration, getAnimateFadeTime, getAnimateHideAcceleration, getAnimateHideTime, getAnimateMoveAcceleration, getAnimateMoveTime, getAnimateRectAcceleration, getAnimateRectTime, getAnimateResizeAcceleration, getAnimateResizeTime, getAnimateScrollAcceleration, getAnimateScrollTime, getAnimateShowAcceleration, getAnimateShowEffect, getAnimateShowTime, getAnimateTime, getAppImgDir, getAriaRole, getAutoDraw, getAutoMaskComponents, getAutoShowParent, getBackgroundColor, getBackgroundImage, getBackgroundPosition, getBackgroundRepeat, getBorder, getBottom, getById, getByJSObject, getByLocalId, getCanAcceptDrop, getCanDrag, getCanDragReposition, getCanDragResize, getCanDrop, getCanDropBefore, getCanFocus, getCanHover, getCanSelectText, getCanvasAutoChild, getCanvasItem, getChildren, getChildrenSnapResizeToGrid, getChildrenSnapToGrid, getClassName, getComponentMask, getComponentMaskDefaults, getContentElement, getContents, getContextMenu, getCursor, getDataPath, getDefaultHeight, getDefaultWidth, getDestroyed, getDestroying, getDisabled, getDisabledCursor, getDisableTouchScrollingForDrag, getDoubleClickDelay, getDragAppearance, getDragIntersectStyle, getDragMaskType, getDragOpacity, getDragRepositionAppearance, getDragRepositionCursor, getDragResizeAppearance, getDragScrollDelay, getDragStartDistance, getDragTarget, getDragType, getDropTypes, getDropTypesAsString, getDynamicContents, getEdgeBackgroundColor, getEdgeCenterBackgroundColor, getEdgeImage, getEdgeMarginSize, getEdgeOffset, getEdgeOpacity, getEdgeShowCenter, getEdgeSize, getEditNode, getEditProxy, getElement, getElement, getEventEdge, getEventEdge, getExtraSpace, getFacetId, getFormItemAutoChild, getFullDataPath, getGroupBorderCSS, getGroupLabelBackgroundColor, getGroupLabelStyleName, getGroupTitle, getHeight, getHeightAsString, getHideUsingDisplayNone, getHoverAlign, getHoverAutoDestroy, getHoverComponent, getHoverDelay, getHoverHeight, getHoverHTML, getHoverMoveWithMouse, getHoverOpacity, getHoverStyle, getHoverVAlign, getHoverWidth, getHoverWrap, getHSnapOrigin, getHSnapOrigin, getHSnapPosition, getHSnapPosition, getHtmlElement, getHtmlPosition, getImage, getImgURL, getImgURL, getInnerContentHeight, getInnerContentWidth, getInnerHeight, getInnerWidth, getIsGroup, getKeepInParentRect, getLayoutAlign, getLeavePageSpace, getLeft, getLeftAsString, getLocateChildrenBy, getLocateChildrenType, getLocatePeersBy, getLocatePeersType, getMargin, getMasterCanvas, getMasterElement, getMatchElement, getMaxHeight, getMaxWidth, getMenuConstructor, getMinHeight, getMinNonEdgeSize, getMinWidth, getMomentumScrollMinSpeed, getMouseStillDownDelay, getMouseStillDownInitialDelay, getNextZIndex, getNoDoubleClicks, getOffsetHeight, getOffsetWidth, getOffsetX, getOffsetY, getOpacity, getOuterElement, getOverflow, getPadding, getPageBottom, getPageLeft, getPageRect, getPageRight, getPageTop, getParentCanvas, getParentElement, getPeers, getPercentBox, getPercentSource, getPosition, getPrefix, getPrintChildrenAbsolutelyPositioned, getPrintHTML, getPrompt, getProportionalResizeModifiers, getProportionalResizing, getRect, getRedrawOnResize, getResizeBarTarget, getResizeFrom, getRight, getScrollbarSize, getScrollBottom, getScrollHeight, getScrollLeft, getScrollRight, getScrollTop, getScrollWidth, getShadowDepth, getShadowImage, getShadowOffset, getShadowSoftness, getShouldPrint, getShowCustomScrollbars, getShowDragShadow, getShowEdges, getShowHover, getShowHoverComponents, getShowResizeBar, getShowShadow, getShowSnapGrid, getShrinkElementOnHide, getSkinImgDir, getSnapAxis, getSnapEdge, getSnapHDirection, getSnapHGap, getSnapOffsetLeft, getSnapOffsetTop, getSnapOnDrop, getSnapResizeToGrid, getSnapTo, getSnapToGrid, getSnapVDirection, getSnapVGap, getStyleName, getTabIndex, getTestInstance, getTitle, getTooltip, getTop, getTopAsString, getTopElement, getUseBackMask, getUseDragMask, getUseNativeDrag, getUseOpacityFilter, getUseTouchScrolling, getValuesManager, getViewportHeight, getViewportWidth, getVisibility, getVisibleHeight, getVisibleWidth, getVSnapOrigin, getVSnapOrigin, getVSnapPosition, getVSnapPosition, getWidth, getWidthAsString, getZIndex, getZIndex, handleHover, hide, hideClickMask, hideClickMask, hideComponentMask, hideContextMenu, imgHTML, imgHTML, imgHTML, intersects, isDirty, isDisabled, isDrawn, isFocused, isVisible, keyUp, layoutChildren, linkHTML, linkHTML, linkHTML, linkHTML, linkHTML, linkHTML, markForDestroy, markForRedraw, markForRedraw, moveAbove, moveBelow, moveBy, moveTo, onAttach, onDetach, onInit, parentResized, printComponents, redraw, redraw, removeChild, removeChild, removePeer, removePeer, resizeBy, resizeTo, resizeTo, scrollBy, scrollByPercent, scrollTo, scrollTo, scrollTo, scrollToBottom, scrollToLeft, scrollToPercent, scrollToRight, scrollToTop, sendToBack, setAccessKey, setAlign, setAllowExternalFilters, setAlwaysShowScrollbars, setAnimateAcceleration, setAnimateFadeTime, setAnimateHideAcceleration, setAnimateHideTime, setAnimateMoveAcceleration, setAnimateMoveTime, setAnimateRectAcceleration, setAnimateRectTime, setAnimateResizeAcceleration, setAnimateResizeTime, setAnimateScrollAcceleration, setAnimateScrollTime, setAnimateShowAcceleration, setAnimateShowEffect, setAnimateShowTime, setAnimateTime, setAppImgDir, setAriaRole, setAriaState, setAutoChildConstructor, setAutoChildProperties, setAutoChildProperties, setAutoChildProperties, setAutoChildProperties, setAutoChildVisibility, setAutoDraw, setAutoHeight, setAutoMaskComponents, setAutoShowParent, setAutoWidth, setBackgroundColor, setBackgroundImage, setBackgroundPosition, setBackgroundRepeat, setBorder, setBottom, setCanAcceptDrop, setCanDrag, setCanDragReposition, setCanDragResize, setCanDrop, setCanDropBefore, setCanFocus, setCanHover, setCanSelectText, setChildren, setChildrenSnapResizeToGrid, setChildrenSnapToGrid, setComponentMaskDefaults, setContents, setContextMenu, setCursor, setDataPath, setDefaultHeight, setDefaultPageSpace, setDefaultProperties, setDefaultWidth, setDisabled, setDisabledCursor, setDisableTouchScrollingForDrag, setDoubleClickDelay, setDragAppearance, setDragIntersectStyle, setDragMaskType, setDragOpacity, setDragRepositionAppearance, setDragRepositionCursor, setDragResizeAppearance, setDragScrollDelay, setDragStartDistance, setDragTarget, setDragType, setDropTypes, setDropTypes, setDynamicContents, setEdgeBackgroundColor, setEdgeCenterBackgroundColor, setEdgeImage, setEdgeMarginSize, setEdgeOffset, setEdgeOpacity, setEdgeShowCenter, setEdgeSize, setEditMode, setEditMode, setEditMode, setElement, setExtraSpace, setFacetId, setGroupBorderCSS, setGroupLabelBackgroundColor, setGroupLabelStyleName, setGroupTitle, setHeight, setHeight, setHeight, setHeight100, setHideUsingDisplayNone, setHoverAlign, setHoverAutoDestroy, setHoverDelay, setHoverHeight, setHoverMoveWithMouse, setHoverOpacity, setHoverStyle, setHoverVAlign, setHoverWidth, setHoverWrap, setHtmlElement, setHtmlPosition, setImage, setImage, setInitHandler, setIsGroup, setKeepInParentRect, setKeepInParentRect, setKeepInParentRect, setLayoutAlign, setLayoutAlign, setLeavePageSpace, setLeft, setLeft, setLocateChildrenBy, setLocateChildrenType, setLocatePeersBy, setLocatePeersType, setLogicalStructure, setMargin, setMatchElement, setMaxHeight, setMaxWidth, setMenuConstructor, setMinHeight, setMinNonEdgeSize, setMinWidth, setMomentumScrollMinSpeed, setMouseStillDownDelay, setMouseStillDownInitialDelay, setNeverUseFilters, setNoDoubleClicks, setOpacity, setOverflow, setPadding, setPageLeft, setPageTop, setParentCanvas, setParentElement, setPeers, setPercentBox, setPercentSource, setPosition, setPrefix, setPrintChildrenAbsolutelyPositioned, setPrompt, setProportionalResizeModifiers, setProportionalResizing, setRect, setRect, setRedrawOnResize, setResizeBarTarget, setResizeFrom, setResizeFrom, setRight, setScrollbarConstructor, setScrollbarSize, setShadowDepth, setShadowImage, setShadowOffset, setShadowSoftness, setShouldPrint, setShowCustomScrollbars, setShowDragShadow, setShowEdges, setShowHover, setShowHoverComponents, setShowResizeBar, setShowShadow, setShowSnapGrid, setShrinkElementOnHide, setSkinImgDir, setSmoothFade, setSnapAxis, setSnapEdge, setSnapHDirection, setSnapHGap, setSnapOffsetLeft, setSnapOffsetTop, setSnapOnDrop, setSnapResizeToGrid, setSnapTo, setSnapToGrid, setSnapVDirection, setSnapVGap, setStyleName, setTabIndex, setTitle, setTooltip, setTop, setTop, setUseBackMask, setUseDragMask, setUseNativeDrag, setUseOpacityFilter, setUseTouchScrolling, setValuesManager, setVisibility, setVisible, setWidth, setWidth, setWidth, setWidth100, setZIndex, shouldDragScroll, show, showClickMask, showComponentMask, showComponentMask, showNextTo, showNextTo, showNextTo, showNextTo, showPrintPreview, showPrintPreview, showPrintPreview, showPrintPreview, showRecursively, updateEditNode, updateHover, updateHover, updateShadow, visibleAtPoint, willAcceptDrop`

    - ### Methods inherited from class com.smartgwt.client.widgets.BaseWidget

      `addDrawHandler, applyFactoryProperties, destroy, doAddHandler, doInit, doOnRender, draw, equals, error, errorIfNotCreated, getAttribute, getAttributeAsBoolean, getAttributeAsDate, getAttributeAsDateArray, getAttributeAsDouble, getAttributeAsElement, getAttributeAsFloat, getAttributeAsFloatArray, getAttributeAsInt, getAttributeAsIntArray, getAttributeAsJavaScriptObject, getAttributeAsMap, getAttributeAsRecord, getAttributeAsString, getAttributeAsStringArray, getConfig, getDOM, getHandlerCount, getID, getInnerHTML, getJsObj, getOrCreateJsObj, getRef, getScClassName, hasAutoAssignedID, hashCode, initNativeObject, internalSetID, internalSetID, isConfigOnly, isCreated, isFactoryCreated, onBind, onDestroy, onDraw, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setConfig, setConfigOnly, setDragTracker, setFactoryCreated, setID, setJavaScriptObject, setLogicalStructure, setNullProperty, setPosition, setProperty, setProperty, setProperty, setProperty, setProperty, setProperty, setProperty, setScClassName, toString`

    - ### Methods inherited from class com.google.gwt.user.client.ui.Widget

      `addAttachHandler, addBitlessDomHandler, addDomHandler, addHandler, asWidget, asWidgetOrNull, createHandlerManager, delegateEvent, doAttachChildren, doDetachChildren, fireEvent, getLayoutData, getParent, isAttached, isOrWasAttached, onBrowserEvent, onLoad, onUnload, removeFromParent, setLayoutData, sinkEvents`

    - ### Methods inherited from class com.google.gwt.user.client.ui.UIObject

      `addStyleDependentName, ensureDebugId, ensureDebugId, ensureDebugId, getStyleElement, getStyleName, getStylePrimaryName, getStylePrimaryName, isVisible, onEnsureDebugId, removeStyleDependentName, removeStyleName, resolvePotentialElement, setElement, setPixelSize, setSize, setStyleDependentName, setStyleName, setStyleName, setStyleName, setStylePrimaryName, setStylePrimaryName, setVisible, sinkBitlessEvent, unsinkEvents`

    - ### Methods inherited from class java.lang.Object

      `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

    - ### Methods inherited from interface com.google.gwt.event.shared.HasHandlers

      `fireEvent`

- - ### Constructor Detail

    - #### DrawPane

          public DrawPane()

    - #### DrawPane

          public DrawPane(com.google.gwt.core.client.JavaScriptObject jsObj)

  - ### Method Detail

    - #### getOrCreateRef

          public static DrawPane getOrCreateRef(com.google.gwt.core.client.JavaScriptObject jsObj)

    - #### changeAutoChildDefaults

          public static void changeAutoChildDefaults(java.lang.String autoChildName,
                                     Canvas defaults)

      Changes the defaults for Canvas AutoChildren named `autoChildName`.
      Parameters:
        `autoChildName` - name of an AutoChild to customize the defaults for.
        `defaults` - Canvas defaults to apply. These defaults override any existing properties without destroying or wiping out non-overridden properties.
      See Also:
        `AutoChildUsage`

    - #### changeAutoChildDefaults

          public static void changeAutoChildDefaults(java.lang.String autoChildName,
                                     FormItem defaults)

      Changes the defaults for FormItem AutoChildren named `autoChildName`.
      Parameters:
        `autoChildName` - name of an AutoChild to customize the defaults for.
        `defaults` - FormItem defaults to apply. These defaults override any existing properties without destroying or wiping out non-overridden properties.
      See Also:
        `AutoChildUsage`

    - #### create

          protected com.google.gwt.core.client.JavaScriptObject create()

      Overrides:
        `create` in class `Canvas`

    - #### setCanDragScroll

          public void setCanDragScroll(boolean canDragScroll)
                                throws java.lang.IllegalStateException

      Can the user drag-scroll the DrawPane?
      Overrides:
        `setCanDragScroll` in class `Canvas`
      Parameters:
        `canDragScroll` - Default value is false
      Throws:
        `java.lang.IllegalStateException` - this property cannot be changed after the component has been created
      See Also:
        `setDrawingWidth(int)`, `setDrawingHeight(int)`

    - #### getCanDragScroll

          public boolean getCanDragScroll()

      Can the user drag-scroll the DrawPane?
      Overrides:
        `getCanDragScroll` in class `Canvas`
      Returns:
        boolean
      See Also:
        `getDrawingWidth()`, `getDrawingHeight()`

    - #### setDrawingHeight

          public void setDrawingHeight(int drawingHeight)
                                throws java.lang.IllegalStateException

      When `canDragScroll` is enabled, this is the height of the area in viewbox coordinates that can be accessed through drag-scrolling.
      Parameters:
        `drawingHeight` - Default value is 1000
      Throws:
        `java.lang.IllegalStateException` - this property cannot be changed after the component has been created

    - #### getDrawingHeight

          public int getDrawingHeight()

      When `canDragScroll` is enabled, this is the height of the area in viewbox coordinates that can be accessed through drag-scrolling.
      Returns:
        int

    - #### setDrawingWidth

          public void setDrawingWidth(int drawingWidth)
                               throws java.lang.IllegalStateException

      When `canDragScroll` is enabled, this is the width of the area in viewbox coordinates that can be accessed through drag-scrolling.
      Parameters:
        `drawingWidth` - Default value is 1000
      Throws:
        `java.lang.IllegalStateException` - this property cannot be changed after the component has been created

    - #### getDrawingWidth

          public int getDrawingWidth()

      When `canDragScroll` is enabled, this is the width of the area in viewbox coordinates that can be accessed through drag-scrolling.
      Returns:
        int

    - #### setDrawItems

          public void setDrawItems(DrawItem... drawItems)
                            throws java.lang.IllegalStateException

      Array of DrawItems to initially display in this DrawPane.
      Parameters:
        `drawItems` - Default value is null
      Throws:
        `java.lang.IllegalStateException` - this property cannot be changed after the component has been created

    - #### getDrawItems

          public DrawItem[] getDrawItems()

      Array of DrawItems to initially display in this DrawPane.
      Returns:
        DrawItem...

    - #### setEditProxyConstructor

          public void setEditProxyConstructor(java.lang.String editProxyConstructor)
                                       throws java.lang.IllegalStateException

      Default class used to construct the `EditProxy` for this component when the component is `first placed into edit mode`.
      Overrides:
        `setEditProxyConstructor` in class `Canvas`
      Parameters:
        `editProxyConstructor` - See `SCClassName` . Default value is "DrawPaneEditProxy"
      Throws:
        `java.lang.IllegalStateException` - this property cannot be changed after the component has been created

    - #### getEditProxyConstructor

          public java.lang.String getEditProxyConstructor()

      Default class used to construct the `EditProxy` for this component when the component is `first placed into edit mode`.
      Overrides:
        `getEditProxyConstructor` in class `Canvas`
      Returns:
        See `SCClassName`

    - #### setGradients

          public void setGradients(Gradient... gradients)
                            throws java.lang.IllegalStateException

      Array of gradients that can be referenced by DrawItems placed on this DrawPane. Each gradient must have an ID assigned to be used for reference.
      Parameters:
        `gradients` - Default value is null
      Throws:
        `java.lang.IllegalStateException` - this property cannot be changed after the component has been created

    - #### getGradients

          public Gradient[] getGradients()

      Array of gradients that can be referenced by DrawItems placed on this DrawPane. Each gradient must have an ID assigned to be used for reference.
      Returns:
        Gradient...

    - #### setRotation

          public void setRotation(float rotation)

      Deprecated. `GwtFloatVsDouble`
      Rotation in degrees for the `DrawPane` as a whole about the center of the `DrawPane`. The positive direction corresponds to clockwise rotation (for example, 45 is rotation clockwise by 45 degrees and -10 is rotation counterclockwise by 10 degrees).
      If this method is called after the component has been drawn/initialized: Sets the `rotation` of the `DrawPane`.
      Parameters:
        `rotation` - the new rotation in degrees. The positive direction corresponds to clockwise rotation.. Default value is 0

    - #### getRotation

          public float getRotation()

      Deprecated. `GwtFloatVsDouble`
      Rotation in degrees for the `DrawPane` as a whole about the center of the `DrawPane`. The positive direction corresponds to clockwise rotation (for example, 45 is rotation clockwise by 45 degrees and -10 is rotation counterclockwise by 10 degrees).
      Returns:
        float

    - #### setRotation

          public void setRotation(double rotation)

      Rotation in degrees for the `DrawPane` as a whole about the center of the `DrawPane`. The positive direction corresponds to clockwise rotation (for example, 45 is rotation clockwise by 45 degrees and -10 is rotation counterclockwise by 10 degrees).
      If this method is called after the component has been drawn/initialized: Sets the `rotation` of the `DrawPane`.
      Parameters:
        `rotation` - the new rotation in degrees. The positive direction corresponds to clockwise rotation.. Default value is 0

    - #### getRotationAsDouble

          public double getRotationAsDouble()

      Rotation in degrees for the `DrawPane` as a whole about the center of the `DrawPane`. The positive direction corresponds to clockwise rotation (for example, 45 is rotation clockwise by 45 degrees and -10 is rotation counterclockwise by 10 degrees).
      Returns:
        double

    - #### setTranslate

          public void setTranslate(int[] translate)
                            throws java.lang.IllegalStateException

      Global translation. This array has two numbers. The first number is the X translation amount in pixels and the second number is the Y translation amount in pixels.
      Parameters:
        `translate` - Default value is null
      Throws:
        `java.lang.IllegalStateException` - this property cannot be changed after the component has been created

    - #### getTranslate

          public int[] getTranslate()

      Global translation. This array has two numbers. The first number is the X translation amount in pixels and the second number is the Y translation amount in pixels.
      Returns:
        int[]

    - #### setZoomLevel

          public void setZoomLevel(float zoomLevel)

      Deprecated. `GwtFloatVsDouble`
      Zoom for the `DrawPane` as a whole, where 1 is normal size.
      If this method is called after the component has been drawn/initialized: Sets the zoom on this `DrawPane` to the specified magnification, maintaining the current viewport position.
      Parameters:
        `zoomLevel` - Desired zoom level as a float where `1.0` is equivalent to 100% magnification. Must be greater than 0.. Default value is 1

    - #### getZoomLevel

          public float getZoomLevel()

      Deprecated. `GwtFloatVsDouble`
      Zoom for the `DrawPane` as a whole, where 1 is normal size.
      Returns:
        float

    - #### setZoomLevel

          public void setZoomLevel(double zoomLevel)

      Zoom for the `DrawPane` as a whole, where 1 is normal size.
      If this method is called after the component has been drawn/initialized: Sets the zoom on this `DrawPane` to the specified magnification, maintaining the current viewport position.
      Parameters:
        `zoomLevel` - Desired zoom level as a float where `1.0` is equivalent to 100% magnification. Must be greater than 0.. Default value is 1

    - #### getZoomLevelAsDouble

          public double getZoomLevelAsDouble()

      Zoom for the `DrawPane` as a whole, where 1 is normal size.
      Returns:
        double

    - #### addDrawItem

          public void addDrawItem(DrawItem item,
                         boolean autoDraw)

      Add a drawItem to this drawPane (if necessary removing it from any other drawPanes)
      Parameters:
        `item` - drawItem to add
        `autoDraw` - If explicitly set to false, and this drawPane is drawn, don't draw the newly added item

    - #### addGradient

          public java.lang.String addGradient(Gradient gradient)

      Add a new gradient to the drawPane shared gradient list (`gradients`). If the gradient does not have an ID a new one will be assigned.
      Parameters:
        `gradient` - gradient to add
      Returns:
        the ID of the gradient (either provided or auto-assigned)

    - #### createLinearGradient

          public java.lang.String createLinearGradient(java.lang.String id,
                                              LinearGradient linearGradient)

      Deprecated. in favor of `DrawPane.addGradient()`
      Creates a linear gradient which can be used by any DrawItem of this DrawPane. Any DrawItem's `fillGradient` can reference the gradient by the given ID.
      Parameters:
        `id` - the ID of the linear gradient
        `linearGradient` - the linear gradient
      Returns:
        id

    - #### createRadialGradient

          public java.lang.String createRadialGradient(java.lang.String id,
                                              RadialGradient radialGradient)

      Deprecated. in favor of `DrawPane.addGradient()`
      Creates a radial gradient which can be used by any DrawItem of this DrawPane. Any DrawItem's `fillGradient` can reference the gradient by the given ID.
      Parameters:
        `id` - the ID of the radial gradient
        `radialGradient` - the radial gradient
      Returns:
        id

    - #### createSimpleGradient

          public java.lang.String createSimpleGradient(java.lang.String id,
                                              SimpleGradient simple)

      Deprecated. in favor of `DrawPane.addGradient()`
      Creates a simple linear gradient which can be used by any DrawItem of this DrawPane. Any DrawItem's `fillGradient` can reference the gradient by the given ID.
      Parameters:
        `id` - the ID of the simple linear gradient
        `simple` - the simple linear gradient
      Returns:
        id

    - #### destroyItems

          public void destroyItems()

      Permanently `destroy` all DrawItems currently associated with this DrawPane, leaving the DrawPane itself intact

    - #### erase

          public void erase()

      Call `DrawItem.erase()` on all DrawItems currently associated with the DrawPane.

      The DrawItems will continue to exist, and you can call draw() on them to make them appear again, or `destroy` to get rid of them permanetly. Use `DrawPane.destroyItems()` to permanently get rid of all DrawItems.

    - #### getDataURL

          public java.lang.String getDataURL()

      Get a "data:" URL encoding the current contents of the DrawPane as a PNG file.

      The returned "data:" URLs can be used anywhere a URL to an image is valid, for example, `src`.

      This method will directly return the data URL on modern browsers when using <canvas>-style rendering (the default), and if there are no `DrawImage`s in this `DrawPane` that load cross-domain images.

      On legacy browers (any version of IE in "quirks" mode, all versions of IE prior to 9.0), or if there is a `DrawImage` that loads a cross-domain image, data URL generation requires a server trip and requires the Smart GWT Server to be installed with the same set of `required .jars` as are required for PDF export of charts in legacy IE. The method will return null and a callback must be passed, which fires when the data URL has been retrieved from the server.

      If the callback is passed but no server trip is required, the callback is fired immediately.

      For obtaining PNG or other image data for use in server-side processing (such as attaching to automated emails or saving to a database), see also the server-side APIs in com.isomorphic.contentexport.ImageExport.

      Returns:
        the data URL (on modern browsers)
      See Also:
        Chart Image Export Example

    - #### getDataURL

          public java.lang.String getDataURL(DataURLCallback callback)

      Get a "data:" URL encoding the current contents of the DrawPane as a PNG file.

      The returned "data:" URLs can be used anywhere a URL to an image is valid, for example, `src`.

      This method will directly return the data URL on modern browsers when using <canvas>-style rendering (the default), and if there are no `DrawImage`s in this `DrawPane` that load cross-domain images.

      On legacy browers (any version of IE in "quirks" mode, all versions of IE prior to 9.0), or if there is a `DrawImage` that loads a cross-domain image, data URL generation requires a server trip and requires the Smart GWT Server to be installed with the same set of `required .jars` as are required for PDF export of charts in legacy IE. The method will return null and a callback must be passed, which fires when the data URL has been retrieved from the server.

      If the callback is passed but no server trip is required, the callback is fired immediately.

      For obtaining PNG or other image data for use in server-side processing (such as attaching to automated emails or saving to a database), see also the server-side APIs in com.isomorphic.contentexport.ImageExport.

      Parameters:
        `callback` - callback to fire when data url is available
      Returns:
        the data URL (on modern browsers)
      See Also:
        Chart Image Export Example

    - #### getGradient

          public Gradient getGradient(java.lang.String gradientID)

      Returns gradient for gradientID.
      Parameters:
        `gradientID` - ID of gradient to retrieve
      Returns:
        the gradient or null if not found

    - #### getSvgString

          public java.lang.String getSvgString()

      Converts this DrawPane to the source of an `<svg>` element equivalent to the current drawing.

      In Pro edition and above, the returned string can be used with `RPCManager.exportImage()` to download an image, or with server-side APIs in com.isomorphic.contentexport.ImageExport to obtain various kinds of images for further server-side processing.

      Returns:
        the source of an `<svg>` element.
      See Also:
        Chart Image Export Example

    - #### removeGradient

          public void removeGradient(java.lang.String gradientID)

      Removes gradient for gradientID.
      Parameters:
        `gradientID` - ID of gradient to remove

    - #### rotate

          public void rotate(double degrees)

      Synonym of `DrawPane.setRotation()`.
      Parameters:
        `degrees` - the new rotation in degrees. The positive direction corresponds to clockwise rotation.

    - #### zoom

          public void zoom(float zoomLevel)

      Deprecated. `GwtFloatVsDouble`
      Synonym of `DrawPane.setZoomLevel()`.
      Parameters:
        `zoomLevel` - Desired zoom level as a float where `1.0` is equivalent to 100% magnification. Must be greater than 0.

    - #### zoom

          public void zoom(double zoomLevel)

      Synonym of `DrawPane.setZoomLevel()`.
      Parameters:
        `zoomLevel` - Desired zoom level as a float where `1.0` is equivalent to 100% magnification. Must be greater than 0.

    - #### bezier

          public static double bezier(double p1,
                      double cp1,
                      double cp2,
                      double p2,
                      double t)

      Computes a cubic Bézier curve polynomial: `B(t) = (1 - t)3P1 + 3(1 - t)2tCP1 + 3(1 - t)t2CP2 + t3P2`
      Parameters:
        `p1` - starting point coordinate
        `cp1` - first control point coordinate
        `cp2` - second control point coordinate
        `p2` - end point coordinate
        `t` - the value of the parameter of the curve, between 0 and 1
      Returns:
        the value of the polynomial `B(t)` at `t`

    - #### bezierExtrema

          public static double[] bezierExtrema(double p1,
                               double cp1,
                               double cp2,
                               double p2)

      Computes the minimum and maximum value of the cubic Bézier curve polynomial defined in `DrawPane.bezier()`, for `0 ≤ t ≤ 1`.
      Parameters:
        `p1` - starting point coordinate
        `cp1` - first control point coordinate
        `cp2` - second control point coordinate
        `p2` - end point coordinate
      Returns:
        the minimum and maximum value of the cubic Bézier curve polynomial

    - #### getBezierBoundingBox

          public static double[] getBezierBoundingBox(Point p1,
                                      Point cp1,
                                      Point cp2,
                                      Point p2)

      Calculate the bounding box of the cubic Bézier curve with endpoints `p1` and `p2` and control points `cp1` and `cp2`.
      Parameters:
        `p1` - start point of the curve
        `cp1` - first cubic Bézier control point
        `cp2` - second cubic Bézier control point
        `p2` - end point of the curve
      Returns:
        the x1, y1, x2, y2 coordinates. The point `(x1, y1)` is the top-left point of the bounding box and the point `(x2, y2)` is the bottom-right point of the bounding box.

    - #### getPolygonPoints

          public static Point[] getPolygonPoints(int width,
                                 int height,
                                 int xc,
                                 int yc,
                                 double[] angles)

      Computes an array of Points for a polygon that has an equal distance from its center to any of its vertices and that fits in the given width and height.
      Parameters:
        `width` - width of target space
        `height` - height of target space
        `xc` - center point x
        `yc` - center point y
        `angles` - the complete list of angles (in radians) with respect to the center point at which the polygon must have vertices
      Returns:
        list of the vertices of the polygon

    - #### getRegularPolygonPoints

          public static Point[] getRegularPolygonPoints(int n,
                                        int width,
                                        int height,
                                        int xc,
                                        int yc,
                                        double startAngle)

      Calls `DrawPane.getPolygonPoints()` with angles spread evenly over the full 360 degrees.
      Parameters:
        `n` - the number of vertices the polygon
        `width` - width of target space
        `height` - height of target space
        `xc` - center point x
        `yc` - center point y
        `startAngle` - the angle (in radians) with respect to the center point of the first vertex of the polygon
      Returns:
        list of the vertices of the regular polygon

    - #### scaleAndCenter

          public static void scaleAndCenter(int width,
                            int height,
                            int xc,
                            int yc,
                            Point... points)

      Computes the top-, left-, bottom-, and right-most coordinates in a list of points, then translates and scales all points to fit the entire shape into the given width and height.
      Parameters:
        `width` - width of target space
        `height` - height of target space
        `xc` - center point x
        `yc` - center point y
        `points` - list of points to scale and translate

    - #### scaleAndCenterBezier

          public static void scaleAndCenterBezier(int width,
                                  int height,
                                  int xc,
                                  int yc,
                                  Point startPoint,
                                  Point endPoint,
                                  Point controlPoint1,
                                  Point controlPoint2)

      Computes the top-, left-, bottom-, and right-most coordinates containing the Bézier curve defined by `startPoint`, `controlPoint1`, `controlPoint2`, and `endPoint`, then translates and scales these four points to fit the entire curve into the given width and height.
      Parameters:
        `width` - width of target space
        `height` - height of target space
        `xc` - center point x
        `yc` - center point y
        `startPoint` - start point of the curve
        `endPoint` - end point of the curve
        `controlPoint1` - first cubic Bézier control point
        `controlPoint2` - second cubic Bézier control point

    - #### setDefaultProperties

          public static void setDefaultProperties(DrawPane drawPaneProperties)

      Class level method to set the default properties of this class. If set, then all existing and subsequently created instances of this class will automatically have default properties corresponding to the properties set on the SmartGWT class instance passed to this function before its underlying SmartClient JS object was created. This is a powerful feature that eliminates the need for users to create a separate hierarchy of subclasses that only alter the default properties of this class. Can also be used for skinning / styling purposes.

      Note: This method is intended for setting default attributes only and will affect all instances of the underlying class (including those automatically generated in JavaScript). This method should not be used to apply standard EventHandlers or override methods for a class - use a custom subclass instead. Calling this method after instances have been created can result in undefined behavior, since it bypasses any setters and a class instance may have already examined a particular property and not be expecting any changes through this route.

      Parameters:
        `drawPaneProperties` - properties that should be used as new defaults when instances of this class are created

    - #### getPrintHTML

          public java.lang.String getPrintHTML(PrintProperties printProperties,
                                      PrintHTMLCallback callback)

      Retrieves printable HTML for this component and all printable subcomponents.

      By default any Canvas with children will simply collect the printable HTML of its children by calling getPrintHTML() on each child that is considered `printable`.

      If overriding this method for a custom component, you should either return a String of printable HTML string directly or return null, and fire the callback (if provided).

      To return an empty print representation, return an empty string ("") rather than null.

      The `printProperties` argument, if passed, must be passed to any subcomponents on which `getPrintHTML()` is called.

      Notes on printing

      To print a `DrawPane` for export on IE8 and earlier, it is `PrintProperties` with `printForExport`:true:

           final PrintProperties pp = new PrintProperties();
           pp.setPrintForExport(true);
           final String exportHTML = drawPane.getPrintHTML(pp, null);

      Note: this is an override point.

      Overrides:
        `getPrintHTML` in class `Canvas`
      Parameters:
        `printProperties` - properties to configure printing behavior - may be null.
        `callback` - optional callback to fire. Generated HTML should be passed to the `PrintHTMLCallback.setHTML(String)` method of the callback.
      Returns:
        null if the print HTML is being generated asynchronously and/or a callback is provided; otherwise, the direct print HTML for this component (but note that returning direct print HTML is a deprecated feature).
      See Also:
        `Printing overview and related methods`

    - #### setLogicalStructure

          public com.smartgwt.logicalstructure.core.LogicalStructureObject setLogicalStructure(com.smartgwt.logicalstructure.widgets.drawing.DrawPaneLogicalStructure s)

      Setter implementing the `LogicalStructure` interface, which supports Eclipse's logical structure debugging facility.

    - #### getLogicalStructure

          public com.smartgwt.logicalstructure.core.LogicalStructureObject getLogicalStructure()

      Getter implementing the `LogicalStructure` interface, which supports Eclipse's logical structure debugging facility.
      Specified by:
        `getLogicalStructure` in interface `LogicalStructure`
      Overrides:
        `getLogicalStructure` in class `Canvas`