chaco.abstract_plot_renderer module

Defines a base class for plot renderers.

class chaco.abstract_plot_renderer.AbstractPlotRenderer(**traits)

Bases: chaco.plot_component.PlotComponent

This is the minimal interface that all plot renderers must support.

Higher-dimensionality plot renderers can implement a richer subclass of this abstract class.

This interface exists mostly to support the development of generic interactors and plot tools.

bgcolor = "transparent"

Overrides the default value inherited from PlotComponent.


Maps a screen space point (sx, sy) to the “index” space of the plot.

Returns a floating point number, not an integer index.

map_index(screen_pt, threshold=0.0, outside_returns_none=True, index_only=False)

Maps a screen space point to an index into the plot’s index array(s).

  • screen_pt ((x,y)) – The screen space point to map.

  • threshold (float) – Optional screen-space distance allowed between screen_pt and the plot; if non-zero, then a screen_pt within this distance is mapped to the neared plot index. (This feature is useful for sparse 2-D data.)

  • outside_returns_none (Boolean) – If True, then if screen_pt is outside the range of the data, the method returns None. If False, it returns the nearest end index in such a case.

  • index_only (Boolean) – If True, then this method maps based only on the index coordinate of screen_pt, and ignores the value coordinate.


index – An index into the plot’s index array(s). Typically this index is just an integer, but if the plot has a 2-D index dimension, then this method returns a tuple of integers. If the input point cannot be mapped to an index, then None is returned.

If screen_pt corresponds to multiple indices, then only the first index is returned.

Return type



Maps an array of data points to screen space and returns an array of screen space points.

resizable = "hv"

Overrides the default value inherited from PlotComponent.