ASCEE/pyqtgraph
5
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Merge pull request #1956 from pijyoi/zerocopy_qba

Browse Source 
arrayToQPath: use QByteArray as backing store
This commit is contained in:
Ogi Moore 2021-08-06 22:22:09 -07:00 committed by GitHub
commit a537bc2b23
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 11 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
pyqtgraph/functions.py
View File

@ -1957,12 +1957,13 @@ def arrayToQPath(x, y, connect='all', finiteCheck=True):
backstore = create_qpolygonf(n)
arr = np.frombuffer(ndarray_from_qpolygonf(backstore), dtype=[('x', 'f8'), ('y', 'f8')])
else:
backstore = bytearray(4 + n*20 + 8)
backstore = QtCore.QByteArray()
backstore.resize(4 + n*20 + 8) # contents uninitialized
backstore.replace(0, 4, struct.pack('>i', n))
# cStart, fillRule (Qt.FillRule.OddEvenFill)
backstore.replace(4+n*20, 8, struct.pack('>ii', 0, 0))
arr = np.frombuffer(backstore, dtype=[('c', '>i4'), ('x', '>f8'), ('y', '>f8')],
count=n, offset=4)
struct.pack_into('>i', backstore, 0, n)
# cStart, fillRule (Qt.FillRule.OddEvenFill)
struct.pack_into('>ii', backstore, 4+n*20, 0, 0)
# Fill array with vertex values
arr['x'] = x
@ -1992,7 +1993,7 @@ def arrayToQPath(x, y, connect='all', finiteCheck=True):
path.addPolygon(backstore)
return path
elif connect == 'pairs':
arr['c'][::2] = 0
arr['c'][0::2] = 0
arr['c'][1::2] = 1 # connect every 2nd point to every 1st one
elif connect == 'finite':
# Let's call a point with either x or y being nan is an invalid point.
@ -2000,7 +2001,8 @@ def arrayToQPath(x, y, connect='all', finiteCheck=True):
# 'c' value of the invalid point. Therefore, we should set 'c' to 0 for
# the next point of an invalid point.
if not use_qpolygonf:
arr[1:]['c'] = isfinite[:-1]
arr['c'][:1] = 0 # the first vertex has no previous vertex to connect
arr['c'][1:] = isfinite[:-1]
else:
sidx = np.nonzero(~isfinite)[0] + 1
chunks = np.split(arr, sidx) # note: the chunks are views
@ -2047,21 +2049,12 @@ def arrayToQPath(x, y, connect='all', finiteCheck=True):
return path
elif connect == 'array':
arr[1:]['c'] = connect_array[:-1]
arr['c'][:1] = 0 # the first vertex has no previous vertex to connect
arr['c'][1:] = connect_array[:-1]
else:
raise ValueError('connect argument must be "all", "pairs", "finite", or array')
arr[0]['c'] = 0 # the first vertex has no previous vertex to connect
# create QDataStream object and stream into QPainterPath
path.strn = backstore
if QT_LIB == "PyQt6" and QtCore.PYQT_VERSION < 0x60101:
# due to issue detailed here:
# https://www.riverbankcomputing.com/pipermail/pyqt/2021-May/043942.html
buf = QtCore.QByteArray(path.strn, len(path.strn))
else:
buf = QtCore.QByteArray(path.strn)
ds = QtCore.QDataStream(buf)
ds = QtCore.QDataStream(backstore)
ds >> path
return path