Function: constantEqualsDefault()
constantEqualsDefault(
channel,value):boolean
True iff value (a plain number, or a [x,y]/[x,y,z] array - the shape
every channel's resolveConstant/constantValue produces) is exactly
this channel's own defaultValue - used by the pass below to skip
applyConstant entirely for a channel whose resolved value is a total
no-op, rather than special-casing that per channel.
Parameters
channel
value
unknown
Returns
boolean