Class PopGraph2D

Object

UIObject

Widget

Panel

SimplePanel

FocusPanel

AbstractGraph<String[]>

GenericPopGraph<String, Network2D>

PopGraph2D

All Implemented Interfaces:

DoubleClickHandler, HasAllDragAndDropHandlers, HasAllFocusHandlers, HasAllGestureHandlers, HasAllKeyHandlers, HasAllMouseHandlers, HasAllTouchHandlers, HasBlurHandlers, HasClickHandlers, HasContextMenuHandlers, HasDoubleClickHandlers, HasDragEndHandlers, HasDragEnterHandlers, HasDragHandlers, HasDragLeaveHandlers, HasDragOverHandlers, HasDragStartHandlers, HasDropHandlers, HasFocusHandlers, HasGestureChangeHandlers, HasGestureEndHandlers, HasGestureStartHandlers, HasKeyDownHandlers, HasKeyPressHandlers, HasKeyUpHandlers, HasMouseDownHandlers, HasMouseMoveHandlers, HasMouseOutHandlers, HasMouseOverHandlers, HasMouseUpHandlers, HasMouseWheelHandlers, HasTouchCancelHandlers, HasTouchEndHandlers, HasTouchMoveHandlers, HasTouchStartHandlers, MouseDownHandler, MouseMoveHandler, MouseOutHandler, MouseUpHandler, MouseWheelHandler, TouchEndHandler, TouchMoveHandler, TouchStartHandler, HasAttachHandlers, EventHandler, HasHandlers, EventListener, AcceptsOneWidget, Focusable, HasFocus, HasOneWidget, HasVisibility, HasWidgets, HasWidgets.ForIsWidget, IsWidget, RequiresResize, SourcesClickEvents, SourcesFocusEvents, SourcesKeyboardEvents, SourcesMouseEvents, SourcesMouseWheelEvents, Iterable<Widget>, AbstractGraph.Shifter, AbstractGraph.Shifting, AbstractGraph.Zoomer, AbstractGraph.Zooming, Network.LayoutListener, ContextMenu.Listener, ContextMenu.Provider, Tooltip.Provider

public class PopGraph2D
extends GenericPopGraph<String, Network2D>
implements AbstractGraph.Shifting

The graphical representation of lattices and network structures in 2D. This class adapts a generic population graph view to a 2D canvas, supporting multiple geometry types (triangular, honeycomb, square variants, linear, and generic network layouts) and providing custom drawing, hit-testing and user interaction behavior.

Responsibilities

• Calculate layout bounds and element sizes for a variety of geometry types based on the current canvas size and configuration.
• Render lattice cells or network nodes and links to a canvas using an internal graphics context.
• Maintain an optional history buffer for linear (time-series) lattices, enabling visualization of past states.
• Map input coordinates (mouse/touch) to node indices for selection and dragging, with geometry-specific hit-test logic.
• Allow interactive shifting of individual network nodes (dragging) and shifting of lattice views.
• Expose export capability to draw into an external MyContext2d context (e.g., for image export or printing).

Supported Geometry Types

• TRIANGULAR — drawn as interleaved up/down triangles
• HONEYCOMB — drawn as regular hexagons
• SQUARE, SQUARE_MOORE, SQUARE_NEUMANN, SQUARE_NEUMANN_2ND — drawn as square grids with several decoration/neighbor variations; supports hierarchical gaps when geometry describes a HIERARCHY
• LINEAR — drawn as rows of cells where the vertical axis can represent time; uses an internal RingBuffer to store historical states
• Generic network — uses Node2D positions and a radius-based scaling to draw nodes and links; supports manual node shifting

Key Concepts & Fields

• data: a String[] holding per-node CSS color values used to paint each cell/node.
• buffer: an optional RingBuffer<String[]> used by linear geometry to retain previous states for history visualization. Capacity is based on visible steps and MAX_LINEAR_SIZE.
• Bounds and sizing: internal fields such as side, dw, dw2, dh, dh3 and dR compute per-cell/node sizes and are recalculated in calcBounds.
• Hierarchy support: when geometry indicates a HIERARCHY, the component accounts for hierarchical gaps and levels (hLevels, hPeriods).
• Interaction flags: hitNode tracks the currently selected node index, hitDragged indicates whether a node is currently being dragged.

Interaction & Events

• Mouse Down: left-click resolves a node via findNodeAt and sets up dragging state and CSS cursor classes.
• Mouse Move: when dragging a selected node, the node position is updated (network nodes) or the view is shifted (lattices). CSS classes are toggled during drag.
• Mouse Up / Touch End: releases dragging state, restores classes, and can update tooltips as needed.

Rendering

The paint method orchestrates drawing:

• When a static lattice layout is available it delegates to dedicated drawXxx methods (drawTriangular, drawHoneycomb, drawSquareLattice, drawSquareNeumann2nd, drawLinearLattice).
• For arbitrary networks the drawNetwork method scales the universe, draws links and nodes (with per-node color optimization) and supports node diameter computation (dR).
• prepCanvas prepares the canvas transform (scale, translation and zoom) and manages a saved graphics state so drawing is isolated.

Sizing & Limits

• MIN_DW, MIN_DH and MIN_DR define minimum drawable dimensions; if elements would be smaller than these thresholds, the graph is disabled and a message is displayed.
• MAX_LINEAR_SIZE controls the maximum retained history length for linear geometries; callers must ensure MAX_LINEAR_SIZE is adequate for their configured canvas/steps, otherwise an exception is thrown during setup.

Performance

Drawing operations use batching and occasional optimizations (e.g., reusing fill style until it changes) but may still be expensive for very large populations or frequent updates. For linear geometries the history buffer size is chosen to balance memory and visible steps; it is lazily allocated.

Extensibility & Limitations

• 3D geometries (CUBE) are not represented graphically in this class and will display an informational message.
• Hit-testing for networks uses node bounding checks (Node2D.isHit) and returns the top-most node when overlaps occur.
• Layouts flagged as LAYOUT_IN_PROGRESS are treated as invalid for hit-testing until the layout completes.

Styling

CSS classes used by the component:

• .evoludo-PopGraph2D — primary graph element
• .evoludo-Label2D — label element
• .evoludo-cursorGrabNode — added while a node is grabbed
• .evoludo-cursorMoveNode — added while a node is being dragged

Many rendering aspects (frame, linkColor, linkWidth, padding, decorated frame) are controlled by the associated style object.

Usage

Instantiate via the view/module infrastructure this project provides. Ensure to call activate() and allow AbstractGraph.calcBounds() to run with the appropriate canvas size; Tooltip.update() should be invoked whenever the underlying population state changes to refresh the visualization. For linear geometries, ensure the MAX_LINEAR_SIZE accommodates the expected width of the viewport.

Author:

Christoph Hauert

Nested Class Summary

Nested classes/interfaces inherited from class AbstractGraph

AbstractGraph.HasLogScaleY, AbstractGraph.HasTrajectory, AbstractGraph.MyContext2d, AbstractGraph.Shifter, AbstractGraph.Shifting, AbstractGraph.ZoomCommand, AbstractGraph.Zoomer, AbstractGraph.Zooming

Nested classes/interfaces inherited from class UIObject

UIObject.DebugIdImpl, UIObject.DebugIdImplEnabled

Nested classes/interfaces inherited from interface HasWidgets

HasWidgets.ForIsWidget

Field Summary

Fields

Modifier and Type	Field	Description
(package private) int	dh	The height of a node for lattices.
(package private) int	dh3	Convenience variable.
(package private) double	dR	The diameter of nodes for networks.
(package private) int	dw	The width of a node for lattices.
(package private) int	dw2	Convenience variable.
(package private) static final int	HIERARCHY_GAP	Convenience variable.
protected boolean	hitDragged	The flag to indicate whether GenericPopGraph.hitNode is being dragged.
(package private) int	hLevels	Convenience variable.
(package private) int[]	hPeriods	Convenience variable.
(package private) boolean	isHierarchy	Convenience variable.
static final int	MAX_LINEAR_SIZE	The maximum size of a linear graph.
(package private) static final int	MIN_DH	The minimum height of a node in pixels.
(package private) static final double	MIN_DR	The minimum diameter of a node in pixels.
(package private) static final int	MIN_DW	The minimum width of a node in pixels.
(package private) int	side	The size of the graph for lattices.

Fields inherited from class GenericPopGraph

animate, colorMap, data, EVOLUDO_CURSOR_NODE, FINDNODEAT_OUT_OF_BOUNDS, FINDNODEAT_UNIMPLEMENTED, geometry, hitNode, invalidated, label, MAX_ANIMATE_LAYOUT_LINKS_DEFAULT, MAX_ANIMATE_LAYOUT_VERTICES_DEFAULT, network, noGraph

Fields inherited from class AbstractGraph

bounds, buffer, canvas, colors, contextMenu, CSS_CURSOR_MOVE_VIEW, CURSOR_GRAB_NODE_CLASS, CURSOR_MOVE_NODE_CLASS, CURSOR_ZOOM_IN_CLASS, CURSOR_ZOOM_OUT_CLASS, DEFAULT_BUFFER_SIZE, doubleClickHandler, element, g, hasMessage, hasZoom, leftMouseButton, logger, logYMenu, markerColors, markers, MIN_BUFFER_SIZE, MIN_MSEC_BETWEEN_UPDATES, module, mouseDownHandler, mouseMoveHandler, mouseOutHandler, mouseUpHandler, mouseWheelHandler, mouseX, mouseY, PIHALF, pinchDist, pinchX, pinchY, scale, shifter, style, tooltip, tooltipProvider, touchEndHandler, touchEndTime, touchMoveHandler, touchStartHandler, updatetime, view, viewCorner, wrapper, zoomer, zoomFactor, zoomInertiaTimer, zoomInMenu, zoomOutMenu, zoomResetMenu

Fields inherited from class UIObject

DEBUG_ID_PREFIX

Fields inherited from interface AbstractGraph.Zooming

ZOOM_INCR, ZOOM_MAX

Constructor Summary

Constructors

Constructor	Description
PopGraph2D(AbstractView<?> view, Module<?> module)	Create a graph for graphically visualizing the structure of a network (or population).

Method Summary

Modifier and Type	Method	Description
void	activate()	Perform necessary preparations to show the graph in the GUI.
void	calcBounds(int width, int height)	Calculate bounds of drawing area.
private void	drawHoneycomb()	Draw honeycomb lattice.
protected void	drawLattice()	Draws structures with static layout of lattices.
private void	drawLinearLattice()	Draw linear lattice with history.
protected void	drawNetwork()	Draws the network.
private void	drawSquareLattice()	Draw square (hierarchical) lattice (SQUARE, SQUARE_MOORE, SQUARE_NEUMANN).
private void	drawSquareNeumann2nd()	Draw the special SQUARE_NEUMANN_2ND lattice.
private void	drawTriangular()	Draw triangular lattice.
void	export(AbstractGraph.MyContext2d ctx)	Export the graphical context ctx.
private int	findHoneycombNode(int x, int y)	Find the index of the node at the location with coordinates (x, y) in a honeycomb lattice.
private int	findLinearNode(int x, int y)	Find the index of the node at the location with coordinates (x, y) in a linear lattice.
private int	findNetworkNode(int sx, int sy)	Locate the node under the given screen coordinates for general network layouts.
int	findNodeAt(int x, int y)	Find the index of the node at the location with coordinates (x, y).
private int	findSquareNode(int x, int y)	Find the index of the node at the location with coordinates (x, y) in a (hierarchical) square lattice.
private int	findTriangularNode(int x, int y)	Find the index of the node at the location with coordinates (x, y) in a triangular lattice.
String	getCSSColorAt(int node)	Get the color of the node at index node as a CSS color string.
private void	handleHoneycomb(int width, int height)	Handle honeycomb lattice geometry.
private void	handleLinear(int width, int height)	Handle linear lattice geometry with history.
private void	handleNetwork(int width, int height)	Handle generic network geometry.
private void	handleNoRepresentation(GeometryType type)	Handle geometries without graphical representation.
private void	handleSquare(int width, int height)	Handle square lattice geometry.
private void	handleTriangular(int width, int height)	Handle triangular lattice geometry.
private int	hierarchyGapAt(int idx)	Compute number of hierarchy gaps that occur before the given index.
protected void	onLoad()
void	onMouseDown(MouseDownEvent event)
void	onMouseMove(MouseMoveEvent event)
void	onMouseUp(MouseUpEvent event)	.evoludo-cursorGrabNode removed from graph element. .evoludo-cursorMoveNode removed from graph element.
void	onTouchEnd(TouchEndEvent event)
void	onTouchMove(TouchMoveEvent event)	move one finger on node shift node.
boolean	paint(boolean force)	Draw the graph.
private boolean	prepCanvas()	Helper method to get the canvas ready for drawing the graph.
void	setGeometry(AbstractGeometry geometry)	Set the geometry backing the graph.
void	shiftNodeBy(int nodeidx, int dx, int dy)	Shift a single node with index nodeidx by (dx, dy).
void	update(boolean isNext)	Update the graph.

Methods inherited from class GenericPopGraph

getColorMap, getData, getGeometry, getNetwork, getTooltipAt, hasAnimatedLayout, hasMessage, hasStaticLayout, invalidate, layoutComplete, layoutNetwork, layoutUpdate, onDoubleClick, onResize, onTouchStart, onUnload, populateContextMenuAt, reset, setColorMap, setDebugEnabled, setGraphLabel

Methods inherited from class AbstractGraph

addContextMenuHandler, autoscale, calcBounds, clearCanvas, clearGraph, clearHistory, clearMessage, contains, convertToScaledCoordinates, convertToScaledCoordinates, deactivate, displayMessage, doUpdate, drawFrame, drawFrame, fill, fillCircle, fillCircle, fillCircle, fillRect, fillTextVertical, getBuffer, getModule, getStyle, hasHistory, init, onMouseOut, onMouseWheel, paint, parse, prependTime2Data, resetTransforms, setBufferCapacity, setColors, setFont, setLogY, setMarkers, setMarkers, setStrokeStyleAt, setTooltipProvider, shift, stroke, strokeCircle, strokeCircle, strokeCircle, strokeLine, strokeLine, strokeRect, zoom, zoom, zoom, zoom

Methods inherited from class FocusPanel

addBlurHandler, addClickHandler, addClickListener, addDoubleClickHandler, addDragEndHandler, addDragEnterHandler, addDragHandler, addDragLeaveHandler, addDragOverHandler, addDragStartHandler, addDropHandler, addFocusHandler, addFocusListener, addGestureChangeHandler, addGestureEndHandler, addGestureStartHandler, addKeyboardListener, addKeyDownHandler, addKeyPressHandler, addKeyUpHandler, addMouseDownHandler, addMouseListener, addMouseMoveHandler, addMouseOutHandler, addMouseOverHandler, addMouseUpHandler, addMouseWheelHandler, addMouseWheelListener, addTouchCancelHandler, addTouchEndHandler, addTouchMoveHandler, addTouchStartHandler, getTabIndex, removeClickListener, removeFocusListener, removeKeyboardListener, removeMouseListener, removeMouseWheelListener, setAccessKey, setFocus, setTabIndex

Methods inherited from class SimplePanel

add, getContainerElement, getWidget, iterator, remove, setWidget, setWidget

Methods inherited from class Panel

add, adopt, clear, doAttachChildren, doDetachChildren, orphan, remove

Methods inherited from class Widget

addAttachHandler, addBitlessDomHandler, addDomHandler, addHandler, asWidget, asWidgetOrNull, createHandlerManager, delegateEvent, fireEvent, getHandlerCount, getLayoutData, getParent, isAttached, isOrWasAttached, onAttach, onBrowserEvent, onDetach, removeFromParent, setLayoutData, sinkEvents, unsinkEvents

Methods inherited from class UIObject

addStyleDependentName, addStyleName, ensureDebugId, ensureDebugId, ensureDebugId, getAbsoluteLeft, getAbsoluteTop, getElement, getOffsetHeight, getOffsetWidth, getStyleElement, getStyleName, getStyleName, getStylePrimaryName, getStylePrimaryName, getTitle, isVisible, isVisible, onEnsureDebugId, removeStyleDependentName, removeStyleName, resolvePotentialElement, setElement, setElement, setHeight, setPixelSize, setSize, setStyleDependentName, setStyleName, setStyleName, setStyleName, setStyleName, setStylePrimaryName, setStylePrimaryName, setTitle, setVisible, setVisible, setWidth, sinkBitlessEvent, toString

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface AbstractGraph.Shifter

shift

Methods inherited from interface AbstractGraph.Zoomer

zoom

Methods inherited from interface AbstractGraph.Zooming

zoom, zoom

Methods inherited from interface ContextMenu.Listener

getAbsoluteLeft, getAbsoluteTop

Methods inherited from interface HasHandlers

fireEvent

Methods inherited from interface HasTouchCancelHandlers

addTouchCancelHandler

Methods inherited from interface HasTouchEndHandlers

addTouchEndHandler

Methods inherited from interface HasTouchMoveHandlers

addTouchMoveHandler

Methods inherited from interface HasTouchStartHandlers

addTouchStartHandler

Methods inherited from interface Iterable

forEach, spliterator

Methods inherited from interface MouseOutHandler

onMouseOut

Methods inherited from interface MouseWheelHandler

onMouseWheel

Methods inherited from interface TouchStartHandler

onTouchStart

Field Details

MAX_LINEAR_SIZE

public static final int MAX_LINEAR_SIZE

The maximum size of a linear graph. This affects memory allocation to retain the history of the graph.

See Also:

• Constant Field Values

side

int side

The size of the graph for lattices.

dw

int dw

The width of a node for lattices.

dw2

int dw2

Convenience variable. One half of the width of a node for lattices, dw/2.

dh

int dh

The height of a node for lattices.

dh3

int dh3

Convenience variable. One third of the height of a node for lattices, dh/3.

dR

double dR

The diameter of nodes for networks.

MIN_DW

static final int MIN_DW

The minimum width of a node in pixels.

See Also:

• Constant Field Values

MIN_DH

static final int MIN_DH

The minimum height of a node in pixels.

See Also:

• Constant Field Values

MIN_DR

static final double MIN_DR

The minimum diameter of a node in pixels.

See Also:

• Constant Field Values

isHierarchy

boolean isHierarchy

Convenience variable. The flag indicating whether the backing geometry is a hierarchical structure.

hLevels

int hLevels

Convenience variable. The number of hierarchical levels.

hPeriods

int[] hPeriods

Convenience variable. The number of units in each hierarchical level.

HIERARCHY_GAP

static final int HIERARCHY_GAP

Convenience variable. The gap between subsequent units in hierarchical structures.

See Also:

• Constant Field Values

hitDragged

protected boolean hitDragged

The flag to indicate whether GenericPopGraph.hitNode is being dragged.

Constructor Details

PopGraph2D

public PopGraph2D(AbstractView<?> view,
 Module<?> module)

Create a graph for graphically visualizing the structure of a network (or population). Allocates the canvas and the label and retrieves the shared tooltip and context menu.

CSS Style Rules

.evoludo-PopGraph2D

the graph element.

.evoludo-Label2D

the label element.

Parameters:

view - the view of this graph

module - the module backing the graph

Method Details

onLoad

protected void onLoad()

Overrides:

onLoad in class GenericPopGraph<String, Network2D>

setGeometry

public void setGeometry(AbstractGeometry geometry)

Description copied from class: GenericPopGraph

Set the geometry backing the graph.

Overrides:

setGeometry in class GenericPopGraph<String, Network2D>

Parameters:

geometry - the structure of the population

activate

public void activate()

Description copied from class: AbstractGraph

Perform necessary preparations to show the graph in the GUI. Attaches mouse and touch handlers for graphs that implement AbstractGraph.Zooming or AbstractGraph.Shifting interfaces.

Overrides:

activate in class GenericPopGraph<String, Network2D>

See Also:

• AbstractGraph.deactivate()

update

public void update(boolean isNext)

Description copied from class: GenericPopGraph

Update the graph.

Overrides:

update in class GenericPopGraph<String, Network2D>

Parameters:

isNext - true if the state has changed

paint

public boolean paint(boolean force)

Draw the graph. For re-drawing the graph, set force to true.

Depending on the backing geometry this either

1. shows a message, if no graphical representation is available, e.g. for 3D cubic lattices, or if there are too many nodes so that each node becomes too small to display on screen.
2. shows lattice geometries.
3. initiates the generic layouting process for arbitrary network structures.

Overrides:

paint in class GenericPopGraph<String, Network2D>

Parameters:

force - true to force re-drawing of graph

Returns:

true if painting skipped

See Also:

• Network2D

drawLattice

protected void drawLattice()

Description copied from class: GenericPopGraph

Draws structures with static layout of lattices.

Specified by:

drawLattice in class GenericPopGraph<String, Network2D>

See Also:

• GenericPopGraph.hasStaticLayout()

drawTriangular

private void drawTriangular()

Draw triangular lattice.

drawHoneycomb

private void drawHoneycomb()

Draw honeycomb lattice.

drawSquareLattice

private void drawSquareLattice()

Draw square (hierarchical) lattice (SQUARE, SQUARE_MOORE, SQUARE_NEUMANN).

hierarchyGapAt

private int hierarchyGapAt(int idx)

Compute number of hierarchy gaps that occur before the given index. This encapsulates the previous inline loop that counted levels until the first non-divisor was encountered.

Parameters:

idx - the row or column index

Returns:

total gap in pixels to subtract/add for this index

drawSquareNeumann2nd

private void drawSquareNeumann2nd()

Draw the special SQUARE_NEUMANN_2ND lattice.

drawLinearLattice

private void drawLinearLattice()

Draw linear lattice with history.

drawNetwork

protected void drawNetwork()

Description copied from class: GenericPopGraph

Draws the network.

Specified by:

drawNetwork in class GenericPopGraph<String, Network2D>

prepCanvas

private boolean prepCanvas()

Helper method to get the canvas ready for drawing the graph.

Returns:

true if the canvas is ready for drawing

calcBounds

public void calcBounds(int width,
 int height)

Description copied from class: AbstractGraph

Calculate bounds of drawing area.

Overrides:

calcBounds in class AbstractGraph<String[]>

Parameters:

width - the width of the drawing area

height - the height of the drawing area

handleNoRepresentation

private void handleNoRepresentation(GeometryType type)

Handle geometries without graphical representation.

Parameters:

type - the geometry type

handleTriangular

private void handleTriangular(int width,
 int height)

Handle triangular lattice geometry.

Parameters:

width - the width of the canvas

height - the height of the canvas

handleHoneycomb

private void handleHoneycomb(int width,
 int height)

Handle honeycomb lattice geometry.

Parameters:

width - the width of the canvas

height - the height of the canvas

handleSquare

private void handleSquare(int width,
 int height)

Handle square lattice geometry.

Parameters:

width - the width of the canvas

height - the height of the canvas

handleLinear

private void handleLinear(int width,
 int height)

Handle linear lattice geometry with history.

Parameters:

width - the width of the canvas

height - the height of the canvas

handleNetwork

private void handleNetwork(int width,
 int height)

Handle generic network geometry.

Parameters:

width - the width of the canvas

height - the height of the canvas

getCSSColorAt

public String getCSSColorAt(int node)

Get the color of the node at index node as a CSS color string.

Specified by:

getCSSColorAt in class GenericPopGraph<String, Network2D>

Parameters:

node - the index of the node

Returns:

the color of the node

findNodeAt

public int findNodeAt(int x,
 int y)

Find the index of the node at the location with coordinates (x, y).

Specified by:

findNodeAt in class GenericPopGraph<String, Network2D>

Parameters:

x - the x-coordinate of the location

y - the y-coordinate of the location

Returns:

the index of the node

findTriangularNode

private int findTriangularNode(int x,
 int y)

Find the index of the node at the location with coordinates (x, y) in a triangular lattice.

Parameters:

x - the x-coordinate of the location

y - the y-coordinate of the location

Returns:

the index of the node

findHoneycombNode

private int findHoneycombNode(int x,
 int y)

Find the index of the node at the location with coordinates (x, y) in a honeycomb lattice.

Parameters:

x - the x-coordinate of the location

y - the y-coordinate of the location

Returns:

the index of the node

findSquareNode

private int findSquareNode(int x,
 int y)

Find the index of the node at the location with coordinates (x, y) in a (hierarchical) square lattice.

Parameters:

x - the x-coordinate of the location

y - the y-coordinate of the location

Returns:

the index of the node

findLinearNode

private int findLinearNode(int x,
 int y)

Find the index of the node at the location with coordinates (x, y) in a linear lattice.

Parameters:

x - the x-coordinate of the location

y - the y-coordinate of the location

Returns:

the index of the node

findNetworkNode

private int findNetworkNode(int sx,
 int sy)

Locate the node under the given screen coordinates for general network layouts.

Parameters:

sx - screen x-coordinate

sy - screen y-coordinate

Returns:

node index or -1 if none hit

onMouseDown

public void onMouseDown(MouseDownEvent event)

If a node has been hit by a left-click, remember the node's index and the current mouse coordinates. This information might be used by subsequent MouseMoveEvents.

If a node has been hit by a left-click, remember the node's index and the current mouse coordinates. This information might be used by subsequent MouseMoveEvents.

CSS Style Rules

.evoludo-cursorGrabNode

added to graph element.

Specified by:

onMouseDown in interface MouseDownHandler

Overrides:

onMouseDown in class AbstractGraph<String[]>

See Also:

• onMouseMove(MouseMoveEvent)

onMouseUp

public void onMouseUp(MouseUpEvent event)

Cancel all interactions with the graph and reset node and mouse information.

CSS Style Rules

.evoludo-cursorMoveView

removed from graph element.

.evoludo-cursorGrabNode

removed from graph element.

.evoludo-cursorMoveNode

removed from graph element.

Specified by:

onMouseUp in interface MouseUpHandler

Overrides:

onMouseUp in class AbstractGraph<String[]>

See Also:

• onMouseMove(MouseMoveEvent)

onMouseMove

public void onMouseMove(MouseMoveEvent event)

If the left mouse-key is pressed the graph is shifted within its viewport. Note this requires that the zoom level of the graph exceeds 1.

CSS Style Rules

.evoludo-cursorMoveView

added to graph element when shifting the view.

If a node has been hit by a MouseDownEvent and is being dragged, the position of the node is shifted. This allows to customize the display of the graph.

CSS Style Rules

.evoludo-cursorMoveNode

added to graph element when dragging a node.

Specified by:

onMouseMove in interface MouseMoveHandler

Overrides:

onMouseMove in class AbstractGraph<String[]>

See Also:

• onMouseDown(MouseDownEvent)

onTouchEnd

public void onTouchEnd(TouchEndEvent event)

The number of touches on the graph changed.

The number of touches on the graph changed.

Specified by:

onTouchEnd in interface TouchEndHandler

Overrides:

onTouchEnd in class AbstractGraph<String[]>

onTouchMove

public void onTouchMove(TouchMoveEvent event)

The graph reacts to different kinds of touch moves:

Move one finger

Shift view

Pinch two fingers

Zoom view

move one finger on node

shift node.

Specified by:

onTouchMove in interface TouchMoveHandler

Overrides:

onTouchMove in class AbstractGraph<String[]>

shiftNodeBy

public void shiftNodeBy(int nodeidx,
 int dx,
 int dy)

Shift a single node with index nodeidx by (dx, dy). Positive dx shift the node to the right and positive dy shift upwards.

Parameters:

nodeidx - the index of the node

dx - the horizontal shift of the node

dy - the vertical shift of the node

export

public void export(AbstractGraph.MyContext2d ctx)

Description copied from class: AbstractGraph

Export the graphical context ctx.

Specified by:

export in class AbstractGraph<String[]>

Parameters:

ctx - the graphical context to export