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.

map_data(screen_pt)

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).

Parameters

• 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.

Returns

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

int

map_screen(data_array)

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.