From: paramat <mat.gregory@virginmedia.com>
Date: Fri, 17 Feb 2017 15:50:51 +0000 (+0000)
Subject: Voxelmanip: Do not emerge or blit to blocks over map gen limit
X-Git-Tag: 0.4.16~427
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=111e7e1cc8316e4812e85fddc579feaeedecbb58;p=oweals%2Fminetest.git

Voxelmanip: Do not emerge or blit to blocks over map gen limit

Placing a structure that extends into mapblocks that extend past
map_gen_limit causes a crash. For example a sapling growing at the
world edge which adds leaves beyond the edge, or placing a structure
using the lua voxelmanip, or placing a schematic or l-system tree.

Do not run the 'load_if_inexistent' block of code if the mapblock
is over limit, this also marks the mapblock with the flag
VMANIP_BLOCK_DATA_INEXIST which later prevents blitting back those
mapblocks.

This fix therefore uses existing functionality by having the same
effect as the 'load_if_inexistent' bool being false.
---

diff --git a/src/map.cpp b/src/map.cpp
index ffba77262..a415bda96 100644
--- a/src/map.cpp
+++ b/src/map.cpp
@@ -3161,7 +3161,7 @@ void MMVManip::initialEmerge(v3s16 blockpos_min, v3s16 blockpos_max,
 		if(block_data_inexistent)
 		{
 
-			if (load_if_inexistent) {
+			if (load_if_inexistent && !blockpos_over_limit(p)) {
 				ServerMap *svrmap = (ServerMap *)m_map;
 				block = svrmap->emergeBlock(p, false);
 				if (block == NULL)