IO: Reversed persistent ID order in exports to Alembic and USD

Each duplicated (a.k.a. instanced) object has a Persistent ID, which
identifies a dupli within the context of its duplicator. This ID
consists of several numbers when there are nested duplis (for example a
mesh instancing empties on its vertices, where each empty instances a
collection). When exporting to Alembic/USD, these are used to uniquely
name the duplicated objects in the export.

This commit reverses the order of the persistent ID numbers, so that the
first number identifies the first level of recursion. This produces
trees like this:

    ABC
     `--Triangle
         |--Triangle
         |--Empty-1
         |    `--Pole-1-0
         |        |--Pole
         |        `--Block-1-1
         |            `--Block
         |--Empty
         |    `--Pole-0
         |        |--Pole
         |        `--Block-1
         |            `--Block
         |--Empty-2
         |    `--Pole-2-0
         |        |--Pole
         |        `--Block-2-1
         |            `--Block
         `--Empty-0
             `--Pole-0-0
                 |--Pole
                 `--Block-0-1
                     `--Block

It is now clearer that `Pole-2-0` and `Block-2-1` are instanced by
`Empty-2`. Before this commit, they would have been named `Pole-0-2` and
`Block-1-2`.
This commit is contained in:
2020-07-07 14:30:55 +02:00
parent 70b1c09d7a
commit 98bee41c8a
5 changed files with 78 additions and 16 deletions

View File

@@ -254,7 +254,7 @@ class DupliGroupExportTest(AbstractAlembicTest):
# `--Triangle
# |--Triangle
# |--Empty-1
# | `--Pole-0-1
# | `--Pole-1-0
# | |--Pole
# | `--Block-1-1
# | `--Block
@@ -264,18 +264,18 @@ class DupliGroupExportTest(AbstractAlembicTest):
# | `--Block-1
# | `--Block
# |--Empty-2
# | `--Pole-0-2
# | `--Pole-2-0
# | |--Pole
# | `--Block-1-2
# | `--Block-2-1
# | `--Block
# `--Empty-0
# `--Pole-0-0
# |--Pole
# `--Block-1-0
# `--Block-0-1
# `--Block
# Now check the resulting Alembic file.
xform = self.abcprop(abc, '/Triangle/Empty-1/Pole-0-1/Block-1-1/.xform')
xform = self.abcprop(abc, '/Triangle/Empty-1/Pole-1-0/Block-1-1/.xform')
self.assertEqual(1, xform['.inherits'])
self.assertAlmostEqualFloatArray(
xform['.vals'],
@@ -288,17 +288,17 @@ class DupliGroupExportTest(AbstractAlembicTest):
# If the property can be gotten, the hierarchy is okay. No need to actually check each xform.
self.abcprop(abc, '/Triangle/.xform')
self.abcprop(abc, '/Triangle/Empty-1/.xform')
self.abcprop(abc, '/Triangle/Empty-1/Pole-0-1/.xform')
self.abcprop(abc, '/Triangle/Empty-1/Pole-0-1/Block-1-1/.xform')
self.abcprop(abc, '/Triangle/Empty-1/Pole-1-0/.xform')
self.abcprop(abc, '/Triangle/Empty-1/Pole-1-0/Block-1-1/.xform')
self.abcprop(abc, '/Triangle/Empty/.xform')
self.abcprop(abc, '/Triangle/Empty/Pole-0/.xform')
self.abcprop(abc, '/Triangle/Empty/Pole-0/Block-1/.xform')
self.abcprop(abc, '/Triangle/Empty-2/.xform')
self.abcprop(abc, '/Triangle/Empty-2/Pole-0-2/.xform')
self.abcprop(abc, '/Triangle/Empty-2/Pole-0-2/Block-1-2/.xform')
self.abcprop(abc, '/Triangle/Empty-2/Pole-2-0/.xform')
self.abcprop(abc, '/Triangle/Empty-2/Pole-2-0/Block-2-1/.xform')
self.abcprop(abc, '/Triangle/Empty-0/.xform')
self.abcprop(abc, '/Triangle/Empty-0/Pole-0-0/.xform')
self.abcprop(abc, '/Triangle/Empty-0/Pole-0-0/Block-1-0/.xform')
self.abcprop(abc, '/Triangle/Empty-0/Pole-0-0/Block-0-1/.xform')
class CurveExportTest(AbstractAlembicTest):