From 52e8a19a390d5b13b4435a565ee5eb593767897f Mon Sep 17 00:00:00 2001 From: Jacob Gardner Date: Sat, 26 Jun 2021 19:49:34 +0000 Subject: [PATCH] Fixes Timer Precision Error Causing Panic (#2362) # Objective Fixes #2361 ## Solution Uses integer division instead of floating-point which prevents precision errors, I think. --- crates/bevy_core/src/time/timer.rs | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/crates/bevy_core/src/time/timer.rs b/crates/bevy_core/src/time/timer.rs index 329fcbeb1b..f09f3f9504 100644 --- a/crates/bevy_core/src/time/timer.rs +++ b/crates/bevy_core/src/time/timer.rs @@ -217,7 +217,8 @@ impl Timer { if self.finished() { if self.repeating() { - self.times_finished = self.percent().floor() as u32; + self.times_finished = + (self.elapsed().as_nanos() / self.duration().as_nanos()) as u32; // Duration does not have a modulo self.set_elapsed(self.elapsed() - self.duration() * self.times_finished); } else { @@ -464,4 +465,20 @@ mod tests { t.tick(Duration::from_secs_f32(0.5)); assert_eq!(t.times_finished(), 0); } + + #[test] + fn times_finished_precise() { + let mut t = Timer::from_seconds(0.01, true); + let duration = Duration::from_secs_f64(1.0 / 3.0); + + t.tick(duration); + assert_eq!(t.times_finished(), 33); + t.tick(duration); + assert_eq!(t.times_finished(), 33); + t.tick(duration); + assert_eq!(t.times_finished(), 33); + // It has one additional tick this time to compensate for missing 100th tick + t.tick(duration); + assert_eq!(t.times_finished(), 34); + } }