X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Flight.h;h=e847e1ce9362cc46b429952d194ab4cd3d323bb1;hb=2bb559be826f4f82b56fb7916e206df55337c258;hp=c1af7fa62dcee09929b013a3cc2da3d21e9ca52f;hpb=102c5e31fe75bc5c02ddb27afe69968ca8dedeed;p=minetest.git

diff --git a/src/light.h b/src/light.h
index c1af7fa62..e847e1ce9 100644
--- 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.
 */
@@ -20,7 +20,7 @@ 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"
 #include "debug.h"
 
 /*
@@ -75,16 +75,55 @@ inline u8 undiminish_light(u8 light)
 
 extern u8 light_decode_table[LIGHT_MAX+1];
 
+// 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)
 		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;
+}
+
+// 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;
+}
+
+// 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