Avoid crash caused by, and improve, 'findSpawnPos()' (#8728)

[oweals/minetest.git] / src / mapgen / mg_ore.cpp

diff --git a/src/mapgen/mg_ore.cpp b/src/mapgen/mg_ore.cpp
index 2974724202bb442af2060d8bf9dcc220127c5426..c36249cb9e1fa0ffe55dfaf6e66dfafefa8b316a 100644 (file)
--- a/src/mapgen/mg_ore.cpp
+++ b/src/mapgen/mg_ore.cpp
@@ -1,7 +1,7 @@
 /*
 Minetest
-Copyright (C) 2014-2016 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
-Copyright (C) 2015-2017 paramat
+Copyright (C) 2014-2018 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
+Copyright (C) 2015-2018 paramat
 
 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU Lesser General Public License as published by
@@ -24,6 +24,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "map.h"
 #include "log.h"
 #include "util/numeric.h"
+#include <cmath>
 #include <algorithm>
 
 
@@ -345,7 +346,7 @@ void OreBlob::generate(MMVManip *vm, int mapseed, u32 blockseed,
                        float ydist = (s32)y1 - (s32)csize / 2;
                        float zdist = (s32)z1 - (s32)csize / 2;
 
-                       noiseval -= (sqrt(xdist * xdist + ydist * ydist + zdist * zdist) / csize);
+                       noiseval -= std::sqrt(xdist * xdist + ydist * ydist + zdist * zdist) / csize;
 
                        if (noiseval < nthresh)
                                continue;
@@ -371,17 +372,23 @@ void OreVein::generate(MMVManip *vm, int mapseed, u32 blockseed,
        PcgRandom pr(blockseed + 520);
        MapNode n_ore(c_ore, 0, ore_param2);
 
-       u32 sizex = (nmax.X - nmin.X + 1);
-
-       if (!noise) {
-               int sx = nmax.X - nmin.X + 1;
-               int sy = nmax.Y - nmin.Y + 1;
-               int sz = nmax.Z - nmin.Z + 1;
-               noise  = new Noise(&np, mapseed, sx, sy, sz);
-               noise2 = new Noise(&np, mapseed + 436, sx, sy, sz);
+       int sizex = nmax.X - nmin.X + 1;
+       int sizey = nmax.Y - nmin.Y + 1;
+       // Because this ore uses 3D noise the perlinmap Y size can be different in
+       // different mapchunks due to ore Y limits. So recreate the noise objects
+       // if Y size has changed.
+       // Because these noise objects are created multiple times for this ore type
+       // it is necessary to 'delete' them here.
+       if (!noise || sizey != sizey_prev) {
+               delete noise;
+               delete noise2;
+               int sizez = nmax.Z - nmin.Z + 1;
+               noise  = new Noise(&np, mapseed, sizex, sizey, sizez);
+               noise2 = new Noise(&np, mapseed + 436, sizex, sizey, sizez);
+               sizey_prev = sizey;
        }
-       bool noise_generated = false;
 
+       bool noise_generated = false;
        size_t index = 0;
        for (int z = nmin.Z; z <= nmax.Z; z++)
        for (int y = nmin.Y; y <= nmax.Y; y++)
@@ -469,7 +476,7 @@ void OreStratum::generate(MMVManip *vm, int mapseed, u32 blockseed,
                                noise_stratum_thickness->result[index] : (float)stratum_thickness) /
                                2.0f;
                        float nmid = noise->result[index];
-                       y0 = MYMAX(nmin.Y, ceil(nmid - nhalfthick));
+                       y0 = MYMAX(nmin.Y, std::ceil(nmid - nhalfthick));
                        y1 = MYMIN(nmax.Y, nmid + nhalfthick);
                } else { // Simple horizontal stratum
                        y0 = nmin.Y;