Skip to content

Legend autopositioning with "spiraling" lines. #7625

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jan 30, 2017
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 4 additions & 0 deletions doc/api/api_changes/2016-12-14-AL_legend-autoposition.rst
Original file line number Diff line number Diff line change
@@ -0,0 +1,4 @@
More accurate legend autopositioning
````````````````````````````````````

Automatic positioning of legends now prefers using the area surrounded by a `Line2D` rather than placing the legend over the line itself.
46 changes: 12 additions & 34 deletions lib/matplotlib/legend.py
Original file line number Diff line number Diff line change
Expand Up @@ -939,47 +939,25 @@ def _find_best_position(self, width, height, renderer, consider=None):
renderer)
for x in range(1, len(self.codes))]

# tx, ty = self.legendPatch.get_x(), self.legendPatch.get_y()

candidates = []
for l, b in consider:
for idx, (l, b) in enumerate(consider):
legendBox = Bbox.from_bounds(l, b, width, height)
badness = 0
# XXX TODO: If markers are present, it would be good to
# take their into account when checking vertex overlaps in
# take them into account when checking vertex overlaps in
# the next line.
badness = legendBox.count_contains(verts)
badness += legendBox.count_contains(offsets)
badness += legendBox.count_overlaps(bboxes)
for line in lines:
# FIXME: the following line is ill-suited for lines
# that 'spiral' around the center, because the bbox
# may intersect with the legend even if the line
# itself doesn't. One solution would be to break up
# the line into its straight-segment components, but
# this may (or may not) result in a significant
# slowdown if lines with many vertices are present.
if line.intersects_bbox(legendBox):
badness += 1

ox, oy = l, b
badness = (legendBox.count_contains(verts)
+ legendBox.count_contains(offsets)
+ legendBox.count_overlaps(bboxes)
+ sum(line.intersects_bbox(legendBox, filled=False)
for line in lines))
if badness == 0:
return ox, oy

candidates.append((badness, (l, b)))

# rather than use min() or list.sort(), do this so that we are assured
# that in the case of two equal badnesses, the one first considered is
# returned.
# NOTE: list.sort() is stable.But leave as it is for now. -JJL
minCandidate = candidates[0]
for candidate in candidates:
if candidate[0] < minCandidate[0]:
minCandidate = candidate

ox, oy = minCandidate[1]
return l, b
# Include the index to favor lower codes in case of a tie.
candidates.append((badness, idx, (l, b)))

return ox, oy
_, _, (l, b) = min(candidates)
return l, b

def contains(self, event):
return self.legendPatch.contains(event)
Expand Down