[x3d-public] Pausing time revisited

[Andreas Plesch]

http://web3d.org/pipermail/x3d-public_web3d.org/2016-December/thread.html#5697

has a previous discussion on pausing a time sensor.

Here are some concrete issues that may need to be addressed in the
Time component spec:

8.4.1 TimeSensor
https://www.web3d.org/documents/specifications/19775-1/V3.3/Part01/components/time.html#TimeSensor

(A) The TimeSensor spec. does not define all fields. Some are are only
defined by pointing to 8.2 Concepts which Don referred to as poor
style. Others, in particular pauseTime and resumeTime, are not defined
at all.

8.2.4.4 Pausing Time
https://www.web3d.org/documents/specifications/19775-1/V3.3/Part01/components/time.html#PausingTime

(B) The chapter uses "internal time" of a sensor without explanation.
I think it differs from time in general in that it can be paused, eg.
lag behind the current time.

(C) Fig. 8.1 is placed as if it belongs to 8.2.4.4 but does not
explain Pausing Time.

(D) 8.4.1 has a formula on how to calculate fraction which uses now as
the current time: 'Let now represent the time at the current
simulation tick.' . To account for pausing it should refer to the
internal time: 'Let now represent the internal time of the sensor at
the current simulation tick.'

I think (A) and (D) are the more serious issues.

[Another question is how stopTime and startTime should be handled
after resuming a paused sensor. Should they be relative to now or to
the internal time ?]

-Andreas

-- 
Andreas Plesch
Waltham, MA 02453