Timers

Timers can record the duration between rendering commands on the CPU and the GPU.

Info

The various objects described on this page are declared in the package Orka.Timers.

Creating a timer

To create a timer, call the function Create_Timer:

Timer_1 : Timer := Create_Timer;

Starting and stopping

To start measuring the duration of rendering commands on the GPU, call the procedure Start:

Timer_1.Start;

If the timer is currently waiting for the GPU duration to become available, then Start does not do anything. After the timer has been started, rendering commands can be issued.

To stop measuring the duration of rendering commands on the GPU, call Stop. If the timer is already waiting for the GPU duration to become available, then Stop does not do anything.

After procedure Stop has been called, the next restart of the timer (by calling Start again) will update the GPU duration if the result has become available by then.

One shot timers

If the timer is used once (not started and stopped repeatedly), then procedure Wait_For_Result needs to be called to wait for the result of the GPU duration to become available. Procedure Wait_For_Result will wait and stall the CPU until the result of the GPU duration is available.

If a timer is started and stopped repeatedly (once per frame), then the GPU duration will become available a few frames after the timer was started.

Querying the durations

To query the duration which the CPU spent while the timer was active, call the function CPU_Duration. It will return a Duration value. To query the duration spent by the GPU, call the function GPU_Duration.

Values will be zero if no results are available.