Update light decoding table size (#6696)

Fix old undiminish_light bug

diff --git a/src/light.cpp b/src/light.cpp
index 4a20c58ab697fac01af1841d3c10fc6e1530538f..c63ffc3bd792e6ea30b805f603e92c2f781d0012 100644 (file)
--- a/src/light.cpp
+++ b/src/light.cpp
@@ -24,9 +24,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #ifndef SERVER
 
-// Length of LIGHT_MAX + 1 means LIGHT_MAX is the last value.
-// LIGHT_SUN is read as LIGHT_MAX from here.
-u8 light_LUT[LIGHT_MAX + 1];
+static u8 light_LUT[LIGHT_SUN + 1];
 
 // The const ref to light_LUT is what is actually used in the code
 const u8 *light_decode_table = light_LUT;
@@ -48,9 +46,9 @@ void set_light_table(float gamma)
 // Gamma correction
        gamma = rangelim(gamma, 0.5f, 3.0f);
 
-       for (size_t i = 0; i < LIGHT_MAX; i++) {
+       for (size_t i = 0; i < LIGHT_SUN; i++) {
                float x = i;
-               x /= LIGHT_MAX;
+               x /= LIGHT_SUN;
                float brightness = a * x * x * x + b * x * x + c * x;
                float boost = d * std::exp(-((x - e) * (x - e)) / (2.0f * f * f));
                brightness = powf(brightness + boost, 1.0f / gamma);
@@ -58,6 +56,6 @@ void set_light_table(float gamma)
                if (i > 1 && light_LUT[i] <= light_LUT[i - 1])
                        light_LUT[i] = light_LUT[i - 1] + 1;
        }
-       light_LUT[LIGHT_MAX] = 255;
+       light_LUT[LIGHT_SUN] = 255;
 }
 #endif

diff --git a/src/light.h b/src/light.h
index 14fd26d1d14d69ee976a13a0b64f27cf8a360cad..f8c4b83c33dd221363a0aa8ea92f20f0fdf7c3a7 100644 (file)
--- a/src/light.h
+++ b/src/light.h
@@ -18,7 +18,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 */
 
 #pragma once
-
+#include <cassert>
 #include "irrlichttypes.h"
 
 /*
@@ -54,11 +54,12 @@ inline u8 diminish_light(u8 light, u8 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)
                return 0;
-       if (light == LIGHT_MAX)
+       if (light >= LIGHT_MAX)
                return light;
 
        return light + 1;
@@ -84,9 +85,9 @@ extern const u8 *light_decode_table;
 // 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];
 }
 
@@ -98,8 +99,8 @@ inline 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;
+       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;