Draft 'step' curve; couldn't get pg builtin to work

win_fixes
Tyler Goodlet 2021-09-17 16:01:28 -04:00
parent 69c2dd866e
commit f4e1362792
1 changed files with 51 additions and 14 deletions

View File

@ -20,6 +20,7 @@ Fast, smooth, sexy curves.
"""
from typing import Tuple
import numpy as np
import pyqtgraph as pg
from PyQt5 import QtCore, QtGui, QtWidgets
@ -29,7 +30,12 @@ from .._profile import pg_profile_enabled
# TODO: got a feeling that dropping this inheritance gets us even more speedups
class FastAppendCurve(pg.PlotCurveItem):
def __init__(self, *args, **kwargs):
def __init__(
self,
*args,
step_mode: bool = False,
**kwargs
) -> None:
# TODO: we can probably just dispense with the parent since
# we're basically only using the pen setting now...
@ -37,6 +43,7 @@ class FastAppendCurve(pg.PlotCurveItem):
self._last_line: QtCore.QLineF = None
self._xrange: Tuple[int, int] = self.dataBounds(ax=0)
self._step_mode: bool = step_mode
# TODO: one question still remaining is if this makes trasform
# interactions slower (such as zooming) and if so maybe if/when
@ -59,23 +66,53 @@ class FastAppendCurve(pg.PlotCurveItem):
prepend_length = istart - x[0]
append_length = x[-1] - istop
# TODO: step mode support
# if self.stepMode in ("center", True): ## support True for back-compat
# x2 = np.empty((len(x),2), dtype=x.dtype)
# x2[:] = x[:, np.newaxis]
# step mode: draw flat top discrete "step"
# over the index space for each datum.
if self._step_mode:
y_out = y.copy()
x_out = x.copy()
x2 = np.empty(
# the data + 2 endpoints on either end for
# "termination of the path".
(len(x) + 1, 2),
# we want to align with OHLC or other sampling style
# bars likely so we need fractinal values
dtype=float,
)
x2[0] = x[0] - 0.5
x2[1] = x[0] + 0.5
x2[1:] = x[:, np.newaxis] + 0.5
# flatten to 1-d
x_out = x2.reshape(x2.size)
# we create a 1d with 2 extra indexes to
# hold the start and (current) end value for the steps
# on either end
y_out = np.empty(
2*len(y) + 2,
dtype=y.dtype
)
y2 = np.empty((len(y), 2), dtype=y.dtype)
y2[:] = y[:,np.newaxis]
# flatten
y_out[1:-1] = y2.reshape(y2.size)
y_out[0] = 0
y_out[-1] = 0
# TODO: see ``painter.fillPath()`` call
# inside parent's ``.paint()`` to get
# a solid brush under the curve.
else:
# by default we only pull data up to the last (current) index
x_out, y_out = x[:-1], y[:-1]
# ## If we have a fill level, add two extra points at either end
# x = x2.reshape(x2.size)
# y2 = np.empty((len(y)+2,2), dtype=y.dtype)
# y2[1:-1] = y[:,np.newaxis]
# y = y2.reshape(y2.size)[1:-1]
# y[0] = self.opts['fillLevel']
# y[-1] = self.opts['fillLevel']
if self.path is None or prepend_length:
self.path = pg.functions.arrayToQPath(
x[:-1],
y[:-1],
x_out,
y_out,
connect='all'
)
profiler('generate fresh path')