Make `LinearRegion` link using epoch-time index

Turned out to be super simple to get the first draft to work since the
fast and slow chart now use the same domain, however, it seems like
maybe there's an offset issue still where the fast may be a couple
minutes ahead of the slow?

Need to dig in a bit..
epoch_indexing_and_dataviz_layer
Tyler Goodlet 2022-12-15 14:26:50 -05:00
parent 530b2731ba
commit edf721f755
1 changed files with 100 additions and 80 deletions

View File

@ -853,92 +853,113 @@ async def link_views_with_region(
hist_pi.addItem(region, ignoreBounds=True)
region.setOpacity(6/16)
viz = rt_chart._vizs[flume.symbol.fqsn]
viz = rt_chart.get_viz(flume.symbol.fqsn)
assert viz
index_field = viz.index_field
# XXX: no idea why this doesn't work but it's causing
# a weird placement of the region on the way-far-left..
# region.setClipItem(viz.graphics)
# poll for datums load and timestep detection
for _ in range(100):
try:
_, _, ratio = flume.get_ds_info()
break
except IndexError:
await trio.sleep(0.01)
continue
if index_field == 'time':
# in the (epoch) index case we can map directly
# from the fast chart's x-domain values since they are
# on the same index as the slow chart.
def update_region_from_pi(
window,
viewRange: tuple[tuple, tuple],
is_manual: bool = True,
) -> None:
# put linear region "in front" in layer terms
region.setZValue(10)
# set the region on the history chart
# to the range currently viewed in the
# HFT/real-time chart.
region.setRegion(viewRange[0])
else:
raise RuntimeError(
'Failed to detect sampling periods from shm!?')
# poll for datums load and timestep detection
for _ in range(100):
try:
_, _, ratio = flume.get_ds_info()
break
except IndexError:
await trio.sleep(0.01)
continue
else:
raise RuntimeError(
'Failed to detect sampling periods from shm!?')
# sampling rate transform math:
# -----------------------------
# define the fast chart to slow chart as a linear mapping
# over the fast index domain `i` to the slow index domain
# `j` as:
#
# j = i - i_offset
# ------------ + j_offset
# j/i
#
# conversely the inverse function is:
#
# i = j/i * (j - j_offset) + i_offset
#
# Where `j_offset` is our ``izero_hist`` and `i_offset` is our
# `izero_rt`, the ``ShmArray`` offsets which correspond to the
# indexes in each array where the "current" time is indexed at init.
# AKA the index where new data is "appended to" and historical data
# if "prepended from".
#
# more practically (and by default) `i` is normally an index
# into 1s samples and `j` is an index into 60s samples (aka 1m).
# in the below handlers ``ratio`` is the `j/i` and ``mn``/``mx``
# are the low and high index input from the source index domain.
# sampling rate transform math:
# -----------------------------
# define the fast chart to slow chart as a linear mapping
# over the fast index domain `i` to the slow index domain
# `j` as:
#
# j = i - i_offset
# ------------ + j_offset
# j/i
#
# conversely the inverse function is:
#
# i = j/i * (j - j_offset) + i_offset
#
# Where `j_offset` is our ``izero_hist`` and `i_offset` is our
# `izero_rt`, the ``ShmArray`` offsets which correspond to the
# indexes in each array where the "current" time is indexed at init.
# AKA the index where new data is "appended to" and historical data
# if "prepended from".
#
# more practically (and by default) `i` is normally an index
# into 1s samples and `j` is an index into 60s samples (aka 1m).
# in the below handlers ``ratio`` is the `j/i` and ``mn``/``mx``
# are the low and high index input from the source index domain.
def update_region_from_pi(
window,
viewRange: tuple[tuple, tuple],
is_manual: bool = True,
def update_region_from_pi(
window,
viewRange: tuple[tuple, tuple],
is_manual: bool = True,
) -> None:
# put linear region "in front" in layer terms
region.setZValue(10)
) -> None:
# put linear region "in front" in layer terms
region.setZValue(10)
# set the region on the history chart
# to the range currently viewed in the
# HFT/real-time chart.
mn, mx = viewRange[0]
ds_mn = (mn - izero_rt)/ratio
ds_mx = (mx - izero_rt)/ratio
lhmn = ds_mn + izero_hist
lhmx = ds_mx + izero_hist
# print(
# f'rt_view_range: {(mn, mx)}\n'
# f'ds_mn, ds_mx: {(ds_mn, ds_mx)}\n'
# f'lhmn, lhmx: {(lhmn, lhmx)}\n'
# )
region.setRegion((
lhmn,
lhmx,
))
# set the region on the history chart
# to the range currently viewed in the
# HFT/real-time chart.
mn, mx = viewRange[0]
ds_mn = (mn - izero_rt)/ratio
ds_mx = (mx - izero_rt)/ratio
lhmn = ds_mn + izero_hist
lhmx = ds_mx + izero_hist
# print(
# f'rt_view_range: {(mn, mx)}\n'
# f'ds_mn, ds_mx: {(ds_mn, ds_mx)}\n'
# f'lhmn, lhmx: {(lhmn, lhmx)}\n'
# )
region.setRegion((
lhmn,
lhmx,
))
# TODO: if we want to have the slow chart adjust range to
# match the fast chart's selection -> results in the
# linear region expansion never can go "outside of view".
# hmn, hmx = hvr = hist_chart.view.state['viewRange'][0]
# print((hmn, hmx))
# if (
# hvr
# and (lhmn < hmn or lhmx > hmx)
# ):
# hist_pi.setXRange(
# lhmn,
# lhmx,
# padding=0,
# )
# hist_linked.graphics_cycle()
# TODO: if we want to have the slow chart adjust range to
# match the fast chart's selection -> results in the
# linear region expansion never can go "outside of view".
# hmn, hmx = hvr = hist_chart.view.state['viewRange'][0]
# print((hmn, hmx))
# if (
# hvr
# and (lhmn < hmn or lhmx > hmx)
# ):
# hist_pi.setXRange(
# lhmn,
# lhmx,
# padding=0,
# )
# hist_linked.graphics_cycle()
# connect region to be updated on plotitem interaction.
rt_pi.sigRangeChanged.connect(update_region_from_pi)
@ -1333,12 +1354,11 @@ async def display_symbol_data(
)
godwidget.resize_all()
# hist_chart.hide()
# await link_views_with_region(
# rt_chart,
# hist_chart,
# flume,
# )
await link_views_with_region(
rt_chart,
hist_chart,
flume,
)
# start graphics update loop after receiving first live quote
ln.start_soon(