Detailed Description

Functions
GlgGraphEdge	GlgGraphAddEdge (GlgGraphLayout graph, GlgGraphNode start_node, GlgGraphNode end_node, GlgObject graphics, GlgLong edge_type, void *data)
	Creates a new edge and adds it to the graph. More...

GlgGraphNode	GlgGraphAddNode (GlgGraphLayout graph, GlgObject graphics, GlgLong node_type, void *data)
	Creates a new node and adds it to the graph. More...

void	GlgGraphCircularLayout (GlgGraphLayout graph)
	Performs a circular layout. More...

GlgGraphLayout	GlgGraphCreate (void)
	Creates a graph layout object. More...

GlgBoolean	GlgGraphCreateGraphics (GlgGraphLayout graph, GlgObject viewport, GlgObject group)
	Loads icons from the palette and creates a GLG drawing to render the graph. More...

GlgGraphLayout	GlgGraphCreateRandom (GlgLong num_nodes, GlgLong num_node_types, GraphType type)
	Creates a demo graph layout and populates it with nodes and edges. More...

void	GlgGraphDeleteEdge (GlgGraphLayout graph, GlgGraphEdge edge)
	Deletes an edge from the graph. More...

void	GlgGraphDeleteNode (GlgGraphLayout graph, GlgGraphNode node)
	Deletes a node from the graph. More...

void	GlgGraphDestroy (GlgGraphLayout graph)
	Destroys all graph layout's objects. More...

void	GlgGraphDestroyGraphics (GlgGraphLayout graph)
	Destroys the graph's drawing and all graphical objects used to render nodes and edges. More...

void	GlgGraphError (char *message)
	Error handler. More...

GlgGraphEdge	GlgGraphFindEdge (GlgGraphLayout graph, GlgObject edge_graphics)
	Finds an edge object by its graphics. More...

GlgGraphNode	GlgGraphFindNode (GlgGraphLayout graph, GlgObject node_graphics)
	Finds a node object by its graphics. More...

GlgGraphEdge	GlgGraphGetEdge (GlgGraphLayout graph, GlgLong index)
	Finds an edge object by its index. More...

GlgLong	GlgGraphGetEdgeIndex (GlgGraphLayout graph, GlgGraphEdge edge)
	Returns an edge's index inside the graph's edge_array. More...

GlgObject	GlgGraphGetGroup (GlgGraphLayout graph)
	Queries the container used to hold graph's nodes and edges. More...

GlgGraphNode	GlgGraphGetNode (GlgGraphLayout graph, GlgLong index)
	Finds a node object by its index. More...

GlgLong	GlgGraphGetNodeIndex (GlgGraphLayout graph, GlgGraphNode node)
	Returns a node's index inside the graph's node array. More...

void	GlgGraphGetNodePosition (GlgGraphLayout graph, GlgGraphNode node, double x, double y, double *z)
	Queries node position. More...

GlgBoolean	GlgGraphGetUntangle (GlgGraphLayout graph)
	Queries if the untangling algorithm was enabled via GlgGraphSetUntangle. More...

GlgObject	GlgGraphGetViewport (GlgGraphLayout graph)
	Queries the viewport of the graph's drawing. More...

void	GlgGraphIncreaseTemperature (GlgGraphLayout graph, GlgBoolean initial)
	Forces the graph to continue layout after it's finished. More...

GlgBoolean	GlgGraphNodesConnected (GlgGraphNode node1, GlgGraphNode node2)
	Connectivity test. More...

void	GlgGraphScramble (GlgGraphLayout graph)
	Demo function: Randomly scrambles the graph's nodes. More...

void	GlgGraphSetDefPalette (GlgObject palette_drawing)
	Sets the default icon palette. More...

void	GlgGraphSetNodePosition (GlgGraphLayout graph, GlgGraphNode node, double x, double y, double z)
	Sets node position in the GLG world coordinates within the graph's dimensions. More...

void	GlgGraphSetPalette (GlgGraphLayout graph, GlgObject palette_drawing)
	Sets a graph's icon palette. More...

void	GlgGraphSetUntangle (GlgGraphLayout graph, GlgBoolean untangle)
	Enables or disables untangling algorithm. More...

GlgBoolean	GlgGraphSpringIterate (GlgGraphLayout graph)
	Performs one iteration of the spring embedder layout. More...

void	GlgGraphUnloadDefPalette (void)
	Unsets the default palette. More...

void	GlgGraphUpdate (GlgGraphLayout graph)
	Updates the graphics display to show results of the spring layout. More...

Function Documentation

◆ GlgGraphAddEdge()

GlgGraphEdge GlgGraphAddEdge	(	GlgGraphLayout	graph,
		GlgGraphNode	start_node,
		GlgGraphNode	end_node,
		GlgObject	graphics,
		GlgLong	edge_type,
		void *	data
	)

Creates a new edge and adds it to the graph.

Parameters

graph	Graph layout object.
start_node	The edge's start node.
end_node	The edge's end node.
graphics	An optional custom edge icon (to override the icon from the palette).
edge_type	Palette index, specifies what icon to use from the edge palette if no custom graphics is specified. This parameter is reserved for the future use and the value of 0 must be used for regular nodes. The value of -1 can be used to define an external edge with no graphics that connects to an external node.
data	Custom data that will be attached to the edge.

Returns: New edge object

◆ GlgGraphAddNode()

GlgGraphNode GlgGraphAddNode	(	GlgGraphLayout	graph,
		GlgObject	graphics,
		GlgLong	node_type,
		void *	data
	)

Creates a new node and adds it to the graph.

Parameters

graph	Graph layout object.
graphics	An optional custom node icon (to override the icon from the palette.)
node_type	Palette index, specifies what icon to use from the node palette if no custom graphics is specified. The value of -1 can be used to define an external node with no graphics. External nodes will not be moved by the layout.
data	Custom data that will be attached to the node.

Returns: New node object.

When a node is created, it is assigned a random initial position. An application can assign a node's initial position in normalized coordinates using GlgNodePosition after the node is created.

◆ GlgGraphCircularLayout()

void GlgGraphCircularLayout ( GlgGraphLayout graph )

Performs a circular layout.

Parameters

graph Graph layout object.

◆ GlgGraphCreate()

GlgGraphLayout GlgGraphCreate ( void )

Creates a graph layout object.

Returns: A new graph layout object.

◆ GlgGraphCreateGraphics()

GlgBoolean GlgGraphCreateGraphics	(	GlgGraphLayout	graph,
		GlgObject	viewport,
		GlgObject	group
	)

Loads icons from the palette and creates a GLG drawing to render the graph.

Parameters

graph	Graph layout object.
viewport	An optional viewport parameter. If it's not NULL, it will be used as a viewport for the graph's drawing, rendering the graph in an existing object hierarchy. If it's NULL, the graph will create a new viewport to render the graph.
group	An optional group parameter. If it's not NULL, it defines the group container to add nodes and edges to (used when several graph layouts reside in the same viewport). If it's NULL, the graph's viewport is used as a container.

Returns: Success or failure status.

◆ GlgGraphCreateRandom()

GlgGraphLayout GlgGraphCreateRandom	(	GlgLong	num_nodes,
		GlgLong	num_node_types,
		GraphType	type
	)

Creates a demo graph layout and populates it with nodes and edges.

Parameters

num_nodes	Number of nodes to create.
num_node_types	Number of node types to use for rendering.
type	Graph type constant: RANDOM_GRAPH, CIRCULAR_GRAPH or STAR_GRAPH.

Returns: The graph layout object.

◆ GlgGraphDeleteEdge()

void GlgGraphDeleteEdge	(	GlgGraphLayout	graph,
		GlgGraphEdge	edge
	)

Deletes an edge from the graph.

Parameters

graph	Graph layout object.
edge	The edge object to be deleted.

◆ GlgGraphDeleteNode()

void GlgGraphDeleteNode	(	GlgGraphLayout	graph,
		GlgGraphNode	node
	)

Deletes a node from the graph.

It also delets all edges connected to the node.

Parameters

graph	Graph layout object.
node	The node object to be deleted.

◆ GlgGraphDestroy()

void GlgGraphDestroy ( GlgGraphLayout graph )

Destroys all graph layout's objects.

Parameters

graph Graph layout object.

◆ GlgGraphDestroyGraphics()

void GlgGraphDestroyGraphics ( GlgGraphLayout graph )

Destroys the graph's drawing and all graphical objects used to render nodes and edges.

Parameters

graph Graph layout object.

◆ GlgGraphError()

void GlgGraphError ( char * message )

Error handler.

It uses the default GLG error handler to display the supplied error message and may be overridden by subclasses to implement custom error handling.

Parameters

message An error message.

◆ GlgGraphFindEdge()

GlgGraphEdge GlgGraphFindEdge	(	GlgGraphLayout	graph,
		GlgObject	edge_graphics
	)

Finds an edge object by its graphics.

It is used to handle mouse selection.

Parameters

graph	Graph layout object.
edge_graphics	The graphical object used to render the edge in the drawing.

Returns: The edge object associated with edge_graphics.

◆ GlgGraphFindNode()

GlgGraphNode GlgGraphFindNode	(	GlgGraphLayout	graph,
		GlgObject	node_graphics
	)

Finds a node object by its graphics.

It is used to handle mouse selections.

Parameters

graph	Graph layout object.
node_graphics	The graphical object used to render the node in the drawing.

Returns: The node object associated with node_graphics.

◆ GlgGraphGetEdge()

GlgGraphEdge GlgGraphGetEdge	(	GlgGraphLayout	graph,
		GlgLong	index
	)

Finds an edge object by its index.

Parameters

graph	Graph layout object.
index	Edge's index inside the graph's edge array.

Returns: The edge object.

◆ GlgGraphGetEdgeIndex()

GlgLong GlgGraphGetEdgeIndex	(	GlgGraphLayout	graph,
		GlgGraphEdge	edge
	)

Returns an edge's index inside the graph's edge_array.

Parameters

graph	Graph layout object.
edge	The edge object.

Returns: The edge's index or NULL if the edge is not in the node array.

◆ GlgGraphGetGroup()

GlgObject GlgGraphGetGroup ( GlgGraphLayout graph )

Queries the container used to hold graph's nodes and edges.

Parameters

graph Graph layout object.

Returns: The group that holds graph's nodes and edges.

◆ GlgGraphGetNode()

GlgGraphNode GlgGraphGetNode	(	GlgGraphLayout	graph,
		GlgLong	index
	)

Finds a node object by its index.

Parameters

graph	Graph layout object.
index	Node's index inside the graph's node array.

Returns: The node object.

◆ GlgGraphGetNodeIndex()

GlgLong GlgGraphGetNodeIndex	(	GlgGraphLayout	graph,
		GlgGraphNode	node
	)

Returns a node's index inside the graph's node array.

Parameters

graph	Graph layout object.
node	The node object.

Returns: The node's index or NULL if the node is not in the node array.

◆ GlgGraphGetNodePosition()

void GlgGraphGetNodePosition	(	GlgGraphLayout	graph,
		GlgGraphNode	node,
		double *	x,
		double *	y,
		double *	z
	)

Queries node position.

Parameters

graph	Graph layout object.
node	The node to query.
x,y,z	Pointers that will receive X, Y and Z node position in the GLG world coordinates.

◆ GlgGraphGetUntangle()

GlgBoolean GlgGraphGetUntangle ( GlgGraphLayout graph )

Queries if the untangling algorithm was enabled via GlgGraphSetUntangle.

The untangling algorithm helps the graph layout to avoid local minimums in the form of intersecting edges. Using it doubles the time it takes to finish the layout.

Parameters

graph Graph layout object.

Returns: True if the untangling algorithm is enabled.

◆ GlgGraphGetViewport()

GlgObject GlgGraphGetViewport ( GlgGraphLayout graph )

Queries the viewport of the graph's drawing.

Parameters

graph Graph layout object.

Returns: The graph's viewport.

◆ GlgGraphIncreaseTemperature()

void GlgGraphIncreaseTemperature	(	GlgGraphLayout	graph,
		GlgBoolean	initial
	)

Forces the graph to continue layout after it's finished.

Parameters

graph	Graph layout object.
initial	If True, increases "temperature" of the graph's nodes by a large increment. If False, increases "temperature" of the graph's nodes by a small increment.

◆ GlgGraphNodesConnected()

GlgBoolean GlgGraphNodesConnected	(	GlgGraphNode	node1,
		GlgGraphNode	node2
	)

Connectivity test.

Parameters

node1	The first node object.
node2	The second node object.

Returns: True if there is an edge connecting the two nodes.

◆ GlgGraphScramble()

void GlgGraphScramble ( GlgGraphLayout graph )

Demo function: Randomly scrambles the graph's nodes.

Parameters

graph Graph layout object.

◆ GlgGraphSetDefPalette()

void GlgGraphSetDefPalette ( GlgObject palette_drawing )

Sets the default icon palette.

The default palette is used by all graph layouts if no graph-specific palette is defined to override the default one.

Parameters

palette_drawing Palette drawing object. See description of the GlgGraphSetPalette method for more details.

◆ GlgGraphSetNodePosition()

void GlgGraphSetNodePosition	(	GlgGraphLayout	graph,
		GlgGraphNode	node,
		double	x,
		double	y,
		double	z
	)

Sets node position in the GLG world coordinates within the graph's dimensions.

The default dimensions are [-800; +800].

Parameters

graph	Graph layout object.
node	The node to position.
x	X coordinate.
y	Y coordinate.
z	Z coordinate.

◆ GlgGraphSetPalette()

void GlgGraphSetPalette	(	GlgGraphLayout	graph,
		GlgObject	palette_drawing
	)

Sets a graph's icon palette.

Parameters

graph	Graph layout object.
palette_drawing	An GLG object containing node and edge icons to be used for rendering the graph's nodes and edges.

The palette drawing must contain node icons named Node0, Node1, Node2 and so on. Each node icon must contain a data resource of the G (point) type named Position", which will be used by the graph layout to position the node. The palette must also contain an edge icon (a polygon object named Edge), which will be used to define the edges' attributes.

◆ GlgGraphSetUntangle()

void GlgGraphSetUntangle	(	GlgGraphLayout	graph,
		GlgBoolean	untangle
	)

Enables or disables untangling algorithm.

Parameters

graph	Graph layout object.
untangle	True to enable untangling, False to disable.

◆ GlgGraphSpringIterate()

GlgBoolean GlgGraphSpringIterate ( GlgGraphLayout graph )

Performs one iteration of the spring embedder layout.

Parameters

graph Graph layout object.

Returns: True if the layout process has finished.

◆ GlgGraphUnloadDefPalette()

void GlgGraphUnloadDefPalette ( void )

Unsets the default palette.

◆ GlgGraphUpdate()

void GlgGraphUpdate ( GlgGraphLayout graph )

Updates the graphics display to show results of the spring layout.

There is no need to update the display after every iteration: it may be updated after every N iterations or just once, when the layout is finished.

If GlgGraphUpdateRate is set to a non-zero value, the GlgGraphSpringIterate function will periodically update the graph's graphics display, see GlgGraphUpdateRate.

Parameters

graph Graph layout object.

Detailed Description

Functions

Function Documentation

◆ GlgGraphAddEdge()

◆ GlgGraphAddNode()

◆ GlgGraphCircularLayout()

◆ GlgGraphCreate()

◆ GlgGraphCreateGraphics()

◆ GlgGraphCreateRandom()

◆ GlgGraphDeleteEdge()

◆ GlgGraphDeleteNode()

◆ GlgGraphDestroy()

◆ GlgGraphDestroyGraphics()

◆ GlgGraphError()

◆ GlgGraphFindEdge()

◆ GlgGraphFindNode()

◆ GlgGraphGetEdge()

◆ GlgGraphGetEdgeIndex()

◆ GlgGraphGetGroup()

◆ GlgGraphGetNode()

◆ GlgGraphGetNodeIndex()

◆ GlgGraphGetNodePosition()

◆ GlgGraphGetUntangle()

◆ GlgGraphGetViewport()

◆ GlgGraphIncreaseTemperature()

◆ GlgGraphNodesConnected()

◆ GlgGraphScramble()

◆ GlgGraphSetDefPalette()

◆ GlgGraphSetNodePosition()

◆ GlgGraphSetPalette()

◆ GlgGraphSetUntangle()

◆ GlgGraphSpringIterate()

◆ GlgGraphUnloadDefPalette()

◆ GlgGraphUpdate()