minetest/src/daynightratio.h

73 lines
1.9 KiB
C
Raw Normal View History

/*
2013-02-24 18:40:43 +01:00
Minetest
2013-02-24 19:38:45 +01:00
Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#pragma once
2012-12-02 17:02:04 +01:00
inline u32 time_to_daynight_ratio(float time_of_day, bool smooth)
{
2012-12-02 17:02:04 +01:00
float t = time_of_day;
if (t < 0.0f)
t += ((int)(-t) / 24000) * 24000.0f;
if (t >= 24000.0f)
t -= ((int)(t) / 24000) * 24000.0f;
if (t > 12000.0f)
t = 24000.0f - t;
const float values[9][2] = {
{4250.0f + 125.0f, 150.0f},
{4500.0f + 125.0f, 150.0f},
{4750.0f + 125.0f, 250.0f},
{5000.0f + 125.0f, 350.0f},
{5250.0f + 125.0f, 500.0f},
{5500.0f + 125.0f, 675.0f},
{5750.0f + 125.0f, 875.0f},
{6000.0f + 125.0f, 1000.0f},
{6250.0f + 125.0f, 1000.0f},
2012-12-02 17:02:04 +01:00
};
if (!smooth) {
2012-12-02 17:02:04 +01:00
float lastt = values[0][0];
for (u32 i = 1; i < 9; i++) {
2012-12-02 17:02:04 +01:00
float t0 = values[i][0];
float switch_t = (t0 + lastt) / 2.0f;
2012-12-02 17:02:04 +01:00
lastt = t0;
if (switch_t <= t)
2012-12-02 17:02:04 +01:00
continue;
2012-12-02 17:02:04 +01:00
return values[i][1];
}
return 1000;
}
if (t <= 4625.0f) // 4500 + 125
return values[0][1];
else if (t >= 6125.0f) // 6000 + 125
return 1000;
for (u32 i = 0; i < 9; i++) {
if (values[i][0] <= t)
continue;
float td0 = values[i][0] - values[i - 1][0];
float f = (t - values[i - 1][0]) / td0;
return f * values[i][1] + (1.0f - f) * values[i - 1][1];
}
return 1000;
}