igraph.drawing.cairo.edge.LightToDarkEdgeDrawer

class documentation

class LightToDarkEdgeDrawer(AlphaVaryingEdgeDrawer):

Edge drawer implementation that draws undirected edges as straight lines and directed edges by using an alpha value of zero (total transparency) at the source and an alpha value of one (full opacity) at the destination. The alpha value is interpolated in-between.

Method __init__ Constructs the edge drawer.

Inherited from AlphaVaryingEdgeDrawer:

Method	`draw_directed_edge`	Draws a directed edge.
Instance Variable	`alpha_at_dest`	Undocumented
Instance Variable	`alpha_at_src`	Undocumented

Inherited from AbstractCairoEdgeDrawer (via AlphaVaryingEdgeDrawer):

Method	`draw_loop_edge`	Draws a loop edge.
Method	`draw_undirected_edge`	Draws an undirected edge.
Instance Variable	`context`	Undocumented
Instance Variable	`palette`	Undocumented
Instance Variable	`VisualEdgeBuilder`	Undocumented
Method	`_construct_visual_edge_builder`	Construct the visual edge builder that will collect the visual attributes of an edge when it is being drawn.

Inherited from AbstractEdgeDrawer (via AlphaVaryingEdgeDrawer, AbstractCairoEdgeDrawer):

Method	`get_label_position`	returns the position where the label of an edge should be drawn. the default implementation returns the midpoint of the edge and an alignment that tries to avoid overlapping the label with the edge.
Method	`get_label_rotation`	Get the rotation angle of the label to align with the edge.
Static Method	`_curvature_to_float`	Converts values given to the 'curved' edge style argument in plotting calls to floating point values.

def __init__(self, context, palette): ¶

overrides igraph.drawing.cairo.edge.AlphaVaryingEdgeDrawer.__init__

Constructs the edge drawer.

Parameters
context	a Cairo context on which the edges will be drawn.
palette	the palette that can be used to map integer color indices to colors when drawing edges