Clang format: only show errors on non whitelisted files

[oweals/minetest.git] / src / light.h

diff --git a/src/light.h b/src/light.h
index 8714269015f5e10d8b193b9d91fe45cefaef4b60..984e6d7c28d5d59b5e182b6f3f3e71f63c084497 100644 (file)
--- a/src/light.h
+++ b/src/light.h
@@ -1,18 +1,18 @@
 /*
-Minetest-c55
-Copyright (C) 2010 celeron55, Perttu Ahola <celeron55@gmail.com>
+Minetest
+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 General Public License as published by
-the Free Software Foundation; either version 2 of the License, or
+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 General Public License for more details.
+GNU Lesser General Public License for more details.
 
-You should have received a copy of the GNU General Public License along
+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.
 */
@@ -20,10 +20,19 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #ifndef LIGHT_HEADER
 #define LIGHT_HEADER
 
-#include "common_irrlicht.h"
+#include "irrlichttypes.h"
 
-// This directly sets the range of light
+/*
+       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.
+// 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
 
@@ -56,18 +65,65 @@ inline u8 undiminish_light(u8 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_SUN)
-               return light_decode_table[LIGHT_MAX];
-       
        if(light > LIGHT_MAX)
-               throw;
+               light = LIGHT_MAX;
        
        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);
+
+       if(i <= 0)
+               return (float)light_decode_table[0] / 255.0;
+       if(i >= LIGHT_MAX)
+               return (float)light_decode_table[LIGHT_MAX] / 255.0;
+
+       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;
+}
+
+void set_light_table(float gamma);
+
+#endif // ifndef SERVER
+
+// 0 <= daylight_factor <= 1000
+// 0 <= lightday, lightnight <= LIGHT_SUN
+// 0 <= return value <= 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)
+               l = LIGHT_SUN;
+       return l;
+}
+
 #endif