Fix clipping in PDF backend #1446
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Ack. This is screwing around with text. Still working... |
| @@ -1535,8 +1535,6 @@ def draw_path_collection(self, gc, master_transform, paths, all_transforms, | |||
| path_codes.append(name) | |||
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| output = self.file.output | |||
| gc = copy.copy(self.gc) | |||
| output(Op.gsave) | |||
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Wow, getting into what this actually does isn't easy. gsave is q and grestore is Q, this corresponds to the PDF specification (http://www.adobe.com/devnet/pdf/pdf_reference.html section 4.4):
There is no way to enlarge the current clipping path or to set a new clipping path
without reference to the current one. However, since the clipping path is part of
the graphics state, its effect can be localized to specific graphics objects by en-
closing the modification of the clipping path and the painting of those objects
between a pair of q and Q operators (see Section 4.3.1, “Graphics State Stack”).
Execution of the Q operator causes the clipping path to revert to the value that
was saved by the q operator, before the clipping path was modified.
So I wonder what effect removing this local clipping path functionality has? @mdboom : would you mind providing some extra detail?
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Yes -- I've gone ahead and reverted #1444. I thought this was a simple, obvious bug, but that turned out to be wrong. |
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Closing because it is fixed by #1450. |
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This fixes a bug introduced in #1444, where the clipping information would be lost when using a path collection. I think this fixes things once and for all, but if not it's probably safest to just revert #1444 which was solving a much less serious bug than this one.