CollisionMoveSimple: Collide with 'ignore' nodes

[minetest.git] / src / light.h

diff --git a/src/light.h b/src/light.h
index 1827ab53a1d72b4f6a553068840c188f2dcd658c..f8c4b83c33dd221363a0aa8ea92f20f0fdf7c3a7 100644 (file)
--- a/src/light.h
+++ b/src/light.h
@@ -1,28 +1,35 @@
 /*
-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.
 */
 
-#ifndef LIGHT_HEADER
-#define LIGHT_HEADER
+#pragma once
+#include <cassert>
+#include "irrlichttypes.h"
 
-#include "common_irrlicht.h"
+/*
+       Lower level lighting stuff
+*/
 
-// This directly sets the range of light
+// 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
@@ -30,45 +37,90 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 inline u8 diminish_light(u8 light)
 {
-       if(light == 0)
+       if (light == 0)
                return 0;
-       if(light >= LIGHT_MAX)
+       if (light >= LIGHT_MAX)
                return LIGHT_MAX - 1;
-               
+
        return light - 1;
 }
 
 inline u8 diminish_light(u8 light, u8 distance)
 {
-       if(distance >= light)
+       if (distance >= light)
                return 0;
-       return  light - distance;
+       return light - distance;
 }
 
 inline u8 undiminish_light(u8 light)
 {
+       assert(light <= LIGHT_SUN);
        // We don't know if light should undiminish from this particular 0.
        // Thus, keep it at 0.
-       if(light == 0)
+       if (light == 0)
                return 0;
-       if(light == LIGHT_MAX)
+       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_SUN)
-               return light_decode_table[LIGHT_MAX];
-       
-       if(light > LIGHT_MAX)
-               throw;
-       
+       // assert(light <= LIGHT_SUN);
+       if (light > LIGHT_SUN)
+               light = LIGHT_SUN;
        return light_decode_table[light];
 }
 
-#endif
+// 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_SUN)
+               return (float)light_decode_table[LIGHT_SUN] / 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;
+}