/*
Minetest
-Copyright (C) 2010 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 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
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#ifndef LIGHT_HEADER
-#define LIGHT_HEADER
-
+#pragma once
+#include <cassert>
#include "irrlichttypes.h"
-#include "debug.h"
-
-/*
- Day/night cache:
- Meshes are cached for different day-to-night transition values
-*/
-
-/*#define DAYNIGHT_CACHE_COUNT 3
-// First one is day, last one is night.
-extern u32 daynight_cache_ratios[DAYNIGHT_CACHE_COUNT];*/
/*
Lower level lighting stuff
*/
// This directly sets the range of light.
-// Actually this is not the real maximum, and this is not the
-// brightest. The brightest is LIGHT_SUN.
+// Actually this is not the real maximum, and this is not the brightest, the
+// brightest is LIGHT_SUN.
+// If changed, this constant as defined in builtin/game/constants.lua must
+// also be changed.
#define LIGHT_MAX 14
// Light is stored as 4 bits, thus 15 is the maximum.
// This brightness is reserved for sunlight
#define LIGHT_SUN 15
-inline u8 diminish_light(u8 light)
-{
- if(light == 0)
- return 0;
- if(light >= LIGHT_MAX)
- return LIGHT_MAX - 1;
-
- return light - 1;
-}
-
-inline u8 diminish_light(u8 light, u8 distance)
-{
- if(distance >= light)
- return 0;
- return light - distance;
-}
-
-inline u8 undiminish_light(u8 light)
-{
- // We don't know if light should undiminish from this particular 0.
- // Thus, keep it at 0.
- if(light == 0)
- return 0;
- if(light == LIGHT_MAX)
- return light;
-
- return light + 1;
-}
-
-extern u8 light_decode_table[LIGHT_MAX+1];
+#ifndef SERVER
+
+/**
+ * \internal
+ *
+ * \warning DO NOT USE this directly; it is here simply so that decode_light()
+ * can be inlined.
+ *
+ * Array size is #LIGHTMAX+1
+ *
+ * The array is a lookup table to convert the internal representation of light
+ * (brightness) to the display brightness.
+ *
+ */
+extern const u8 *light_decode_table;
// 0 <= light <= LIGHT_SUN
// 0 <= return value <= 255
inline u8 decode_light(u8 light)
{
- if(light > LIGHT_MAX)
- light = LIGHT_MAX;
-
+ // assert(light <= LIGHT_SUN);
+ if (light > LIGHT_SUN)
+ light = LIGHT_SUN;
return light_decode_table[light];
}
// 0.0 <= light <= 1.0
// 0.0 <= return value <= 1.0
-inline float decode_light_f(float light_f)
-{
- s32 i = (u32)(light_f * LIGHT_MAX + 0.5);
+float decode_light_f(float light_f);
- if(i <= 0)
- return (float)light_decode_table[0] / 255.0;
- if(i >= LIGHT_MAX)
- return (float)light_decode_table[LIGHT_MAX] / 255.0;
+void set_light_table(float gamma);
- float v1 = (float)light_decode_table[i-1] / 255.0;
- float v2 = (float)light_decode_table[i] / 255.0;
- float f0 = (float)i - 0.5;
- float f = light_f * LIGHT_MAX - f0;
- return f * v2 + (1.0 - f) * v1;
-}
+#endif // ifndef SERVER
// 0 <= daylight_factor <= 1000
// 0 <= lightday, lightnight <= LIGHT_SUN
inline u8 blend_light(u32 daylight_factor, u8 lightday, u8 lightnight)
{
u32 c = 1000;
- u32 l = ((daylight_factor * lightday + (c-daylight_factor) * lightnight))/c;
- if(l > LIGHT_SUN)
+ u32 l = ((daylight_factor * lightday + (c - daylight_factor) * lightnight)) / c;
+ if (l > LIGHT_SUN)
l = LIGHT_SUN;
return l;
}
-
-// 0.0 <= daylight_factor <= 1.0
-// 0 <= lightday, lightnight <= LIGHT_SUN
-// 0 <= return value <= 255
-inline u8 blend_light_f1(float daylight_factor, u8 lightday, u8 lightnight)
-{
- u8 l = ((daylight_factor * decode_light(lightday) +
- (1.0-daylight_factor) * decode_light(lightnight)));
- return l;
-}
-
-#endif
-