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design: activation: add missing markup

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Reynaldo H. Verdejo Pinochet 2017-01-13 11:09:11 -08:00
parent ba81d06984
commit e184065fb8
1 changed files with 5 additions and 5 deletions
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@ -23,10 +23,10 @@ will return without doing anything. Otherwise it will call the
activation function of the pad. activation function of the pad.
Because the core does not know in which mode to activate a pad (PUSH or Because the core does not know in which mode to activate a pad (PUSH or
PULL), it delegates that choice to a method on the pad, activate(). The PULL), it delegates that choice to a method on the pad, `activate()`. The
activate() function of a pad should choose whether to operate in PUSH or `activate()` function of a pad should choose whether to operate in PUSH or
PULL mode. Once the choice is made, it should call `activate_mode()` with PULL mode. Once the choice is made, it should call `activate_mode()` with
the selected activation mode. The default activate() function will call the selected activation mode. The default `activate()` function will call
`activate_mode()` with `#GST_PAD_MODE_PUSH`, as it is the default `activate_mode()` with `#GST_PAD_MODE_PUSH`, as it is the default
mechanism for data flow. A sink pad that supports either mode of mechanism for data flow. A sink pad that supports either mode of
operation might call `activate_mode(PULL)` if the SCHEDULING query operation might call `activate_mode(PULL)` if the SCHEDULING query
@ -37,7 +37,7 @@ Consider the case `fakesrc ! fakesink`, where fakesink is configured to
operate in PULL mode. State changes in the pipeline will start with operate in PULL mode. State changes in the pipeline will start with
fakesink, which is the most downstream element. The core will call fakesink, which is the most downstream element. The core will call
`activate()` on fakesink’s sink pad. For fakesink to go into PULL mode, it `activate()` on fakesink’s sink pad. For fakesink to go into PULL mode, it
needs to implement a custom activate() function that will call needs to implement a custom `activate()` function that will call
`activate_mode(PULL)` on its sink pad (because the default is to use PUSH `activate_mode(PULL)` on its sink pad (because the default is to use PUSH
mode). `activate_mode(PULL)` is then responsible for starting the task mode). `activate_mode(PULL)` is then responsible for starting the task
that pulls from fakesrc:src. Clearly, fakesrc needs to be notified that that pulls from fakesrc:src. Clearly, fakesrc needs to be notified that
@ -55,7 +55,7 @@ on identity’s source pad would need to activate its sink pad in pull
mode as well, which should propagate all the way to fakesrc. mode as well, which should propagate all the way to fakesrc.
If, on the other hand, `fakesrc ! fakesink` is operating in PUSH mode, If, on the other hand, `fakesrc ! fakesink` is operating in PUSH mode,
the activation sequence is different. First, activate() on fakesink:sink the activation sequence is different. First, `activate()` on fakesink:sink
calls `activate_mode(PUSH)` on fakesink:sink. Then fakesrc’s pads are calls `activate_mode(PUSH)` on fakesink:sink. Then fakesrc’s pads are
activated: sources first, then sinks (of which fakesrc has none). activated: sources first, then sinks (of which fakesrc has none).
fakesrc:src’s activation function is then called. fakesrc:src’s activation function is then called.