From 5b8363af0084786a7e949ae8fa16bde046f8ffda Mon Sep 17 00:00:00 2001 From: Paramat Date: Thu, 4 Apr 2019 23:30:10 +0100 Subject: [PATCH] Stabilise 'day night ratio' to fix object brightness flicker (#8417) Previously, when basic shaders were enabled, the function time_to_daynight_ratio() returned values jumping between 149 and 150 between times 4375 and 4625, and values jumping between 999 and 1000 between times 6125 and 6375, (and the corresponding times at sunset) due to tiny float errors in the interpolation code. This caused the light level returned by blend_light() to jump between 14 and 15, which became noticeable recently as those light levels were given different visual brightnesses. Add early returns to avoid the problematic interpolation, and to avoid unnecessary running of the loop. --- src/daynightratio.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/src/daynightratio.h b/src/daynightratio.h index f959cdf6c..a7b93234e 100644 --- a/src/daynightratio.h +++ b/src/daynightratio.h @@ -52,15 +52,17 @@ inline u32 time_to_daynight_ratio(float time_of_day, bool smooth) return 1000; } + if (t <= 4625) // 4500 + 125 + return values[0][1]; + else if (t >= 6125) // 6000 + 125 + return 1000; for (u32 i=0; i < sizeof(values) / sizeof(*values); i++) { if (values[i][0] <= t) continue; - if (i == 0) - return values[i][1]; + float td0 = values[i][0] - values[i-1][0]; float f = (t - values[i-1][0]) / td0; return f * values[i][1] + (1.0 - f) * values[i-1][1]; } return 1000; - }