Fix various clang-tidy reported performance-type-promotion-in-math-fn

[minetest.git] / src / util / numeric.cpp

diff --git a/src/util/numeric.cpp b/src/util/numeric.cpp
index a48a72a8a8e8c912d8d2062c2423f2123ee9b75a..cb984d8cb5b60879f7f11bb158c2162afca11848 100644 (file)
--- a/src/util/numeric.cpp
+++ b/src/util/numeric.cpp
@@ -20,10 +20,11 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "numeric.h"
 
 #include "log.h"
-#include "../constants.h" // BS, MAP_BLOCKSIZE
-#include "../noise.h" // PseudoRandom, PcgRandom
-#include "../threading/mutex_auto_lock.h"
+#include "constants.h" // BS, MAP_BLOCKSIZE
+#include "noise.h" // PseudoRandom, PcgRandom
+#include "threading/mutex_auto_lock.h"
 #include <cstring>
+#include <cmath>
 
 
 // myrand
@@ -161,3 +162,16 @@ bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
 
        return true;
 }
+
+s16 adjustDist(s16 dist, float zoom_fov)
+{
+       // 1.775 ~= 72 * PI / 180 * 1.4, the default on the client
+       const float default_fov = 1.775f;
+       // heuristic cut-off for zooming
+       if (zoom_fov > default_fov / 2.0f)
+               return dist;
+
+       // new_dist = dist * ((1 - cos(FOV / 2)) / (1-cos(zoomFOV /2))) ^ (1/3)
+       return round(dist * cbrt((1.0f - std::cos(default_fov / 2.0f)) /
+               (1.0f - std::cos(zoom_fov / 2.0f))));
+}