forked from jaildesigner-jailgames/jaildoctors_dilemma
40 lines
1.2 KiB
C++
40 lines
1.2 KiB
C++
#include "utils/delta_timer.hpp"
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DeltaTimer::DeltaTimer() noexcept
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: last_counter_(SDL_GetPerformanceCounter()),
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perf_freq_(static_cast<double>(SDL_GetPerformanceFrequency())),
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time_scale_(1.0f) {
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}
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float DeltaTimer::tick() noexcept {
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const Uint64 now = SDL_GetPerformanceCounter();
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const Uint64 diff = (now > last_counter_) ? (now - last_counter_) : 0;
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last_counter_ = now;
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const double seconds = static_cast<double>(diff) / perf_freq_;
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return static_cast<float>(seconds * static_cast<double>(time_scale_));
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}
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float DeltaTimer::peek() const noexcept {
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const Uint64 now = SDL_GetPerformanceCounter();
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const Uint64 diff = (now > last_counter_) ? (now - last_counter_) : 0;
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const double seconds = static_cast<double>(diff) / perf_freq_;
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return static_cast<float>(seconds * static_cast<double>(time_scale_));
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}
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void DeltaTimer::reset(Uint64 counter) noexcept {
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if (counter == 0) {
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last_counter_ = SDL_GetPerformanceCounter();
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} else {
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last_counter_ = counter;
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}
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}
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void DeltaTimer::setTimeScale(float scale) noexcept {
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time_scale_ = std::max(scale, 0.0f);
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}
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float DeltaTimer::getTimeScale() const noexcept {
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return time_scale_;
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}
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