# Data corruption importing landscape to 4.7 **URL:** \ **Category:** World Creation\ **Tags:** UE4-7, unreal-engine, Collision, Landscape, question\ **Created:** [February 28, 2015, 7:21pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532 "2015-02-28T19:21:50Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![ZorbaTHut\_1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@ZorbaTHut\_1](https://forums.unrealengine.com/u/ZorbaTHut_1)\ **Post date:** [February 28, 2015, 7:21pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/1 "2015-02-28T19:21:50Z")
I’m having trouble updating a project to 4.7. On first load, the landscape looks and works fine. If I save the map, then reopen it, the landscape is corrupted in a strange manner - it _looks_ fine, but the collisions are in completely the wrong places. This is most immediately visible when regenerating and showing the navmesh. First load: ![31622-highresscreenshot00000.png](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/f/b/2fbd03821e87e527e32bd08c513119c311a6bf59.png) With navmesh: ![31623-highresscreenshot00001.png](https://d3kjluh73b9h9o.cloudfront.net/original/4X/6/f/9/6f976734cc0dccc34dd07057cc0aee7ad93ac1ed.png) Close, re-open, regenerate navmesh: ![31624-highresscreenshot00002.png](https://d3kjluh73b9h9o.cloudfront.net/original/4X/a/a/9/aa91b423f45a00fdd51d9ac2601a3aa3d568bce8.png) Note the curious periodic behavior - it looks like it’s just using the wrong tiles in the wrong places. It’s also quite odd that it’s still rendering the landscape in the right place, it’s merely collision data that is corrupt. I’ve tried resampling the terrain on first load, in the hopes that it will fix the collisions, but this merely corrupted the actual terrain data in a new and exciting way. How can I fix this? Obviously this is unusable if I can’t save my level 😃 ---
**Author:** ![ZorbaTHut\_1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@ZorbaTHut\_1](https://forums.unrealengine.com/u/ZorbaTHut_1)\ **Post date:** [February 28, 2015, 7:56pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/2 "2015-02-28T19:56:45Z")
Dysfunctional fix: I figured that the geometry was right but the collision wasn’t, so maybe if I could regenerate the collision from the geometry, it would work. I took a zero-strength huge brush and just waved it over the entire terrain. Fixed everything up like a charm. . . . Aaand then broke again when I saved and reloaded. This turns out to not a functioning solution. Still need assistance ☹ ---
**Author:** ![anonymous\_user\_b9532c9a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_b9532c9a](https://forums.unrealengine.com/u/anonymous_user_b9532c9a)\ **Post date:** [March 1, 2015, 3:48pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/3 "2015-03-01T15:48:20Z")
Hi ZorbaTHut, I have just a few questions to be able to better assist you with this: Is the terrain generated in editor or was it a heightmap imported? What are you using to regenerate the collision? Is the terrain in the persistent level or in a sublevel, additionally are you using World Browser? ---
**Author:** ![ZorbaTHut\_1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@ZorbaTHut\_1](https://forums.unrealengine.com/u/ZorbaTHut_1)\ **Post date:** [March 1, 2015, 10:48pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/4 "2015-03-01T22:48:23Z")
Generated in editor, persistent level, not using World Browser because I literally have exactly one level in this game so far :V By “regenerate the collision” I mean “choose sculpt, set brush size to 8192, set brush strength to 0.0, wave brush over entire world, watch navmesh fix itself”. I’m happy to send you the game files if you want, btw, just be aware it’s about half a gigabyte and I’d need to know where to upload it. ---
**Author:** ![anonymous\_user\_b9532c9a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_b9532c9a](https://forums.unrealengine.com/u/anonymous_user_b9532c9a)\ **Post date:** [March 3, 2015, 12:38am UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/5 "2015-03-03T00:38:18Z")
If you upload the project to a dedicated FTP server such as dropbox and either post here or pm the link to me I’ll be happy to pull it and see what may be occurring. ---
**Author:** ![ZorbaTHut\_1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@ZorbaTHut\_1](https://forums.unrealengine.com/u/ZorbaTHut_1)\ **Post date:** [March 3, 2015, 2:23pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/6 "2015-03-03T14:23:38Z")
PM’ed the link to you. Many thanks for taking a look! ---
**Author:** ![anonymous\_user\_b9532c9a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_b9532c9a](https://forums.unrealengine.com/u/anonymous_user_b9532c9a)\ **Post date:** [March 3, 2015, 11:31pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/7 "2015-03-03T23:31:37Z")
Try using the console command “RecreateLandscapeCollision”. I opened your project and did not experience any problems with the landscape collision or the navmesh. Do you have any steps I can take to reproduce what you are seeing on your end? ---
**Author:** ![ZorbaTHut\_1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@ZorbaTHut\_1](https://forums.unrealengine.com/u/ZorbaTHut_1)\ **Post date:** [March 6, 2015, 3:43am UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/8 "2015-03-06T03:43:06Z")
Repro steps: - Sync to 4.7.1-release (I haven’t tried 4.7.2-release yet) - Build in DebugGame (others caused the same problem) - Open project - Hit P to show navmesh - Verify that navmesh looks correct (it was saved from the last execution) - Choose Build-\>Build Paths - Verify that navmesh now looks totally broken - Set the landscape Sculpt tool to maximum brush size and zero tool strength - Paint over the landscape; watch navmesh fix itself in the painted regions - Save map, quit - Return to “Open Project” step “RecreateLandscapeCollision” actually breaks it even worse. Any tile with corrupted collision ends up with _no_ collision, which means you can’t click on it with the zero-strength Sculpt tool to regenerate. You have to click on nearby tiles (which, thankfully, does work.) Edit: Downloaded 4.7.2 through the launcher, same repro steps behave nearly identically. The only difference is that it’s now picking a different collision tile to duplicate in incorrect places. ---
**Author:** ![anonymous\_user\_b9532c9a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_b9532c9a](https://forums.unrealengine.com/u/anonymous_user_b9532c9a)\ **Post date:** [March 8, 2015, 6:17pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/9 "2015-03-08T18:17:03Z")
I have another potential solution, try the workaround suggested here: > **[Character commonly falls through landscape mesh](https://forums.unrealengine.com/questions/51759/character-commonly-falls-through-landscape-mesh.html)** > > There seem to be invisible gaps and areas where the landscape mesh allows my player character to fall through it. Visually there are no gaps, and the wireframe looks solid, but the character tends to clip through the mesh a lot, especially on slopes. ---
**Author:** ![ZorbaTHut\_1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@ZorbaTHut\_1](https://forums.unrealengine.com/u/ZorbaTHut_1)\ **Post date:** [March 10, 2015, 11:44am UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/10 "2015-03-10T11:44:06Z")
As I said in the original post, second paragraph from the bottom, resampling the landscape trashes the data rather badly. It looks like some parts are offset by one entire tile and some parts aren’t. The result is not usable. Have you been able to duplicate the bug, following my instructions exactly, on 4.7.2 downloaded from the patcher? I’d appreciate it if you tried - I’m going to ask a friend to do the same, to see if it’s a problem with UE4 or with my computer (though I think that’s doubtful). ---
**Author:** ![anonymous\_user\_b9532c9a](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_b9532c9a](https://forums.unrealengine.com/u/anonymous_user_b9532c9a)\ **Post date:** [March 10, 2015, 8:28pm UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/11 "2015-03-10T20:28:06Z")
Well, I’m not certain what changed between last week and this week, but I finally managed to reproduce it! I entered a bug report, UE-11583 to be assessed by the development staff. ---
**Author:** ![ZorbaTHut\_1](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@ZorbaTHut\_1](https://forums.unrealengine.com/u/ZorbaTHut_1)\ **Post date:** [March 11, 2015, 5:20am UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/12 "2015-03-11T05:20:02Z")
Yay, sort of! :V Since I don’t believe I can see your bug tracker yet, please let me know if there’s any updates; I do most of my development through a slightly modified UE4 anyway, so I can easily patch code in if it fixes the issue. Right now working is a real pain. ---
**Author:** ![DevilsD](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/devilsd/32/890854_2.png) [@DevilsD](https://forums.unrealengine.com/u/DevilsD)\ **Post date:** [March 14, 2015, 12:54am UTC](https://forums.unrealengine.com/t/data-corruption-importing-landscape-to-4-7/308532/13 "2015-03-14T00:54:29Z")
Ive been having this issue as well. Im glad its been reproducible and someone posted about it. Its quite an annoying bug especially when i cant properly play test my levels. Im sure there probably isnt any updates on the status of this bug report a couple of days after but i would really like to know when this would be fixed also.