Remove all definitions / uses of _draw_component #743
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| self._draw_ticks(gc) | ||
| self._draw_labels(gc) | ||
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| self._cache_valid = True | ||
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| def _draw_overlay(self, gc, view_bounds=None, mode="normal"): |
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_draw_overlay and overlay are now currently the exact same method. Perhaps one should just call the other to avoid the duplication. I think it would make more sense to have overlay call _draw_overlay.
AFAIK we need to keep both methods, but this should be investigated more closely.
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I think it would make more sense to have overlay call _draw_overlay.
sounds good to me.
AFAIK we need to keep both methods, but this should be investigated more closely.
I'm not a 100% sure why both methods need to exist. I know that _draw_overlay is needed by the new (and currently used) way of drawing the various layers in a chaco plot. Not sure what overlay is used for.
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Looking at this PR again I realize that overlay and _draw_overlay do very slightly different things. I think it is going to be worth the deeper investigation into what both are uesd for / if we can refine things down so only 1 is necessary at all.
If they are in fact both needed it is possible they will need to exist stand alone with very similar (largely copied) code, but some minor discrepancies.
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Digging into enable:
overlay is a method defined on AbstractOverlay, and it takes other_component as an argument. Effectively the overlay draws itself on top of another component.
_draw_overlay originates from Component which keeps track of a list of AbstractOverlays, and when _draw_overlay is called, it iterates over each of those overlays and calls their respective overlay methods, passing in itself as the other_component.
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So, I think what makes sense is that classes which are decedents from AbstractOverlay should only need to define overlay not _draw_overlay.
It is a bit strange because AbstractOverlay subclasses Component so it does technically have a _draw_overlay method. However, for Component _draw_overlay gets called via the _draw method. But _draw is overridden by AbstractOverlay and simply calls overlay if self.component is not None.
So, in summary, I believe we can delete all the definitions of _draw_overlay on subclasses of AbstractOverlay since they are actually unused. overlay is the method that actually does the work. Since the current classes which do override _draw_overlay do not also override _draw, nothing ever actually calls _draw_overlay.
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Looking closer, some differences between enable.AbstractOverlay and chaco.AbstractOverlay include:
- enable defines
_do_layout(default is justpass), anddo_layoutmethods, which chaco does not.do_layout(per the docstring) differs from theComponent.do_layoutmethod in that it allows passing an optionalcomponentarg. - in the
_drawmethod, chaco callssuperifself.componentisNone. enable simply returns.
Number 2 is what makes me think maybe there are scenarios in which _draw_component gets called / is needed if we try to draw an Overlay for which component is None. ie a stand alone overlay (which I will have to look for use cases / examples of ...)
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For instance, the _draw_overlay use on Tooltip and its subclass DataLabel is needed, since they override draw and call PlotComponent._draw directly.
I do not see any cases in which PlotAxis does not have a component set (every time it is instantiated in the chaco codebase a component is passed in), however theoretically one could try drawing an Axis standalone (although i can't imagine why) in which case not having _draw_overlay will cause a break...
I am of two minds if it should be removed or not for the cases of PlotAxis and Grid here. If it is to stay, because the two methods do slightly different things, I believe they will both need to stay as is with some duplication (ie overlay can't just call _draw_overlay).
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@rahulporuri I apologize in advance that this is an overly wordy brain dump, but what are your thoughts on this? I hope my findings make sense
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I can't fully digest these findings at the moment - so my instinct is to simply defer this question to a later time. Can you write up these findings in an issue? I apologize for the delay in responding to your comments - it'll probably involve additional effort to recollect everything and put together a meaningful PR.
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No worries, I will open an issue
| # This method should be folded into self._draw_plot(), but is here for | ||
| # backwards compatibilty with non-draw-order stuff. |
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This comment effectively sums up the aim of this PR
| @@ -60,8 +60,8 @@ class RegressionOverlay(LassoOverlay): | |||
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| def _draw_component(self, gc, view_bounds=None, mode="normal"): | |||
| super()._draw_component(gc, view_bounds, mode) | |||
| def overlay(self, other_component, gc, view_bounds=None, mode="normal"): | |||
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I tested this by running examples/demo/basic/regression.py and everything seems to work as expected
| """ | ||
| # What we're really trying to do with a grid is plot contour lines in | ||
| # the space of the plot. In a rectangular plot, these will always be | ||
| # straight lines. | ||
| if not self.visible: | ||
| return | ||
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| self._compute_ticks(other_component) |
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This method now only differs from _draw_overlay in this line and the self._cache_valid = False line as this is what overlay had done differently previously as well
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@aaronayres35 looks like there are merge conflicts on this PR. Can you address them? |
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Looks like CI is happy and the merge conflicts have been resolved. Can you merge and backport this to the 5.0 maintenance branch? |
* remove all definitions of _draw_component * flake8 * component is not an argument for _draw_overlay
closes #736
Note that
_draw_componenthas been removed from enable in enthought/enable#814It was a deprecated method that was a part of the old rendering approach.
These occurrences were all cases in which
_draw_componenthad been overwritten in chaco and called in a few places. This was intended to preserve backwards compatibility, but is now no longer necessary. The logic can simply be copied over into the appropriate methods (which previously called_draw_component).