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 a9e7ae5840be0849dc09569fb976aecc07237a1d..cb984d8cb5b60879f7f11bb158c2162afca11848 100644 (file)
--- a/src/util/numeric.cpp
+++ b/src/util/numeric.cpp
@@ -18,107 +18,16 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 */
 
 #include "numeric.h"
-#include "mathconstants.h"
 
 #include "log.h"
-#include "../constants.h" // BS, MAP_BLOCKSIZE
-#include "../noise.h" // PseudoRandom, PcgRandom
-#include "../threading/mutex_auto_lock.h"
-#include <string.h>
-#include <iostream>
-
-UNORDERED_MAP<u16, std::vector<v3s16> > FacePositionCache::m_cache;
-Mutex FacePositionCache::m_cache_mutex;
-// Calculate the borders of a "d-radius" cube
-// TODO: Make it work without mutex and data races, probably thread-local
-std::vector<v3s16> FacePositionCache::getFacePositions(u16 d)
-{
-       MutexAutoLock cachelock(m_cache_mutex);
-       if (m_cache.find(d) != m_cache.end())
-               return m_cache[d];
+#include "constants.h" // BS, MAP_BLOCKSIZE
+#include "noise.h" // PseudoRandom, PcgRandom
+#include "threading/mutex_auto_lock.h"
+#include <cstring>
+#include <cmath>
 
-       generateFacePosition(d);
-       return m_cache[d];
 
-}
-
-void FacePositionCache::generateFacePosition(u16 d)
-{
-       m_cache[d] = std::vector<v3s16>();
-       if(d == 0) {
-               m_cache[d].push_back(v3s16(0,0,0));
-               return;
-       }
-       if(d == 1) {
-               /*
-                       This is an optimized sequence of coordinates.
-               */
-               m_cache[d].push_back(v3s16( 0, 1, 0)); // top
-               m_cache[d].push_back(v3s16( 0, 0, 1)); // back
-               m_cache[d].push_back(v3s16(-1, 0, 0)); // left
-               m_cache[d].push_back(v3s16( 1, 0, 0)); // right
-               m_cache[d].push_back(v3s16( 0, 0,-1)); // front
-               m_cache[d].push_back(v3s16( 0,-1, 0)); // bottom
-               // 6
-               m_cache[d].push_back(v3s16(-1, 0, 1)); // back left
-               m_cache[d].push_back(v3s16( 1, 0, 1)); // back right
-               m_cache[d].push_back(v3s16(-1, 0,-1)); // front left
-               m_cache[d].push_back(v3s16( 1, 0,-1)); // front right
-               m_cache[d].push_back(v3s16(-1,-1, 0)); // bottom left
-               m_cache[d].push_back(v3s16( 1,-1, 0)); // bottom right
-               m_cache[d].push_back(v3s16( 0,-1, 1)); // bottom back
-               m_cache[d].push_back(v3s16( 0,-1,-1)); // bottom front
-               m_cache[d].push_back(v3s16(-1, 1, 0)); // top left
-               m_cache[d].push_back(v3s16( 1, 1, 0)); // top right
-               m_cache[d].push_back(v3s16( 0, 1, 1)); // top back
-               m_cache[d].push_back(v3s16( 0, 1,-1)); // top front
-               // 18
-               m_cache[d].push_back(v3s16(-1, 1, 1)); // top back-left
-               m_cache[d].push_back(v3s16( 1, 1, 1)); // top back-right
-               m_cache[d].push_back(v3s16(-1, 1,-1)); // top front-left
-               m_cache[d].push_back(v3s16( 1, 1,-1)); // top front-right
-               m_cache[d].push_back(v3s16(-1,-1, 1)); // bottom back-left
-               m_cache[d].push_back(v3s16( 1,-1, 1)); // bottom back-right
-               m_cache[d].push_back(v3s16(-1,-1,-1)); // bottom front-left
-               m_cache[d].push_back(v3s16( 1,-1,-1)); // bottom front-right
-               // 26
-               return;
-       }
-
-       // Take blocks in all sides, starting from y=0 and going +-y
-       for(s16 y=0; y<=d-1; y++) {
-               // Left and right side, including borders
-               for(s16 z=-d; z<=d; z++) {
-                       m_cache[d].push_back(v3s16(d,y,z));
-                       m_cache[d].push_back(v3s16(-d,y,z));
-                       if(y != 0) {
-                               m_cache[d].push_back(v3s16(d,-y,z));
-                               m_cache[d].push_back(v3s16(-d,-y,z));
-                       }
-               }
-               // Back and front side, excluding borders
-               for(s16 x=-d+1; x<=d-1; x++) {
-                       m_cache[d].push_back(v3s16(x,y,d));
-                       m_cache[d].push_back(v3s16(x,y,-d));
-                       if(y != 0) {
-                               m_cache[d].push_back(v3s16(x,-y,d));
-                               m_cache[d].push_back(v3s16(x,-y,-d));
-                       }
-               }
-       }
-
-       // Take the bottom and top face with borders
-       // -d<x<d, y=+-d, -d<z<d
-       for(s16 x=-d; x<=d; x++)
-       for(s16 z=-d; z<=d; z++) {
-               m_cache[d].push_back(v3s16(x,-d,z));
-               m_cache[d].push_back(v3s16(x,d,z));
-       }
-}
-
-/*
-    myrand
-*/
+// myrand
 
 PcgRandom g_pcgrand;
 
@@ -253,3 +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))));
+}