Timer¶

Overview¶

class omdi::Timer¶

Timer class for measuring elapsed time and frame delta time.

The omdi::Timer class provides a simple high-resolution timer suitable for render loops and simulations. It measures:

the total elapsed time since construction, and
the per-frame delta time between consecutive omdi::Timer::tick() calls.

Internally, it uses std::chrono::high_resolution_clock.

Data members¶

std::chrono::time_point<std::chrono::high_resolution_clock> omdi::Timer::m_now¶: Timestamp of the most recent frame (last call to omdi::Timer::tick()).

const std::chrono::time_point<std::chrono::high_resolution_clock> omdi::Timer::m_start¶

Timestamp when the timer was constructed.

This value is constant for the lifetime of the timer and is used as the reference for computing total elapsed time.

std::size_t omdi::Timer::m_frame¶

Current frame counter.

Incremented by omdi::Timer::tick() each time it is called.

double omdi::Timer::m_delta¶

Time in seconds between the last two frames.

Updated on each call to omdi::Timer::tick(). Initialized to 1.0.

double omdi::Timer::m_elapsed¶

Total elapsed time in seconds since the timer was constructed.

Updated on each call to omdi::Timer::tick().

Constructor¶

omdi::Timer::Timer()¶

Construct a timer and initialize timestamps.

Sets omdi::Timer::m_now and omdi::Timer::m_start to the current std::chrono::high_resolution_clock time, with frame counter, delta, and elapsed values initialized accordingly.

Public interface¶

void omdi::Timer::tick()¶

Advance the timer by one frame.

This function:

obtains the current time from std::chrono::high_resolution_clock,
updates omdi::Timer::m_elapsed with the total elapsed seconds since omdi::Timer::m_start,
updates omdi::Timer::m_delta with the time difference (in seconds) between the new timestamp and the previous omdi::Timer::m_now,
stores the new timestamp in omdi::Timer::m_now,
increments omdi::Timer::m_frame.

Typically called once per frame in the main loop.

std::size_t omdi::Timer::frame() const¶

Get the current frame count.

Returns:: Number of times omdi::Timer::tick() has been called since construction.

double omdi::Timer::delta() const¶

Get the time elapsed between the last two frames.

Returns:: Delta time in seconds (as updated by the most recent omdi::Timer::tick() call).

double omdi::Timer::elapsed() const¶

Get the total elapsed time since the timer was constructed.

Returns:: Elapsed time in seconds since omdi::Timer::m_start.