Im currently involved in making a third person cooperative mobile game in Unity and in said game there will be an area for players to walk around in with various elevations and whatnot throughout the field. Its designed to be set up with 4 biomes in the area to go along with the games theme but I was wondering what would be the best way to mask the "boundaries" or "cut off points" in this area? From certain vantage points its pretty obvious that the terrain used to make the world simply stops and I was wondering if anyone knew any tips and insights on how to best mask these boundaries without too much "padding" in the game area in order to keep it relatively less taxing on a mobile device. Thank you in advance.


2 Answers 2


You need to blend in natural looking borders. Different biomes need different types.


  • Rock walls that are obviously to high to climb
  • Cliffs you cannot possibly climb down. You could make the player fall and kill himself here.
  • Rivers
  • Fences for animals or private property


  • buildings
  • blocked roads (concrete blocks and those signs)
  • fences or brick walls
  • crashed vehicles

You need to model a bit beyond the border and perhaps block view above the camera height so you can have a skybox around your world that will be shown.


Changing biomes is a whole different thing and very much depends on your needs. Minecraft for examle switches from biome to biome from one tile to the next. If you want a gradual switch in biomes you have to blend things along the border.

You need to create a mask along the border. I mask is a black/white image that can hold two textures. One is shown on pure black, the other on pure white. With grey levels you can mix the two textures. Obviously you should also blend in the objects like a view forest tree's expand outward to a savanna and you can spot some yellow grass in the front tree line. To get it perfectly has much more to do with design skill and observing the real world then making games.

  • \$\begingroup\$ I think he meant the boundaries between different biomes, not the overall boundaries… \$\endgroup\$
    – o0'.
    Commented Jul 25, 2015 at 10:44
  • 1
    \$\begingroup\$ its pretty obvious that the terrain used to make the world simply stops. Hence I thought he is talking about "the end of the world". But since I read your comment I doubt this myself too. \$\endgroup\$
    – Madmenyo
    Commented Jul 25, 2015 at 11:14
  • \$\begingroup\$ Well I culd use help with both aspects. Both the end of the world and borders between biomes. There is a forest area bordered by a desert and a beach, the beach is bordered by the volcanic area on the other side and it comes back around to the desert laid out in a 4 square pattern. Should I make the terrains larger to make the transitions smoother? \$\endgroup\$
    – Jacob Neal
    Commented Jul 25, 2015 at 18:39
  • \$\begingroup\$ I'll add to my answer. \$\endgroup\$
    – Madmenyo
    Commented Jul 25, 2015 at 18:42
  • \$\begingroup\$ @JacobNeal perhaps you could accept an answer if it answers this question for you. \$\endgroup\$
    – Madmenyo
    Commented Sep 24, 2015 at 5:29

There is two techniques for hiding the boundaries between disparate terrains.

  1. Blend over some distance. This is usually the best looking but requires that you have tiles that can be blended. This works well for grass, dirt and water terrain textures, for examples.

  2. A simpler approach is to use decorations/fringes to hide the seams at the boundaries. Similar to how the wood trim around your door hides the ugly gap between the door frame and the drywall. Example. at it's most basic, you might use randomly strewn rocks, bushes or trees to cover up the seams and break up any obvious straight lines.

You can also combine both of these approaches to make it even more natural looking.

For world boundaries, a simple solution is to use fog so the player simply can't see anything outside of the bounds.

  • \$\begingroup\$ Alright, I've decided to expand the size of the terrains in the game to give better impressions of transitions and more buffer area for the boundaries but im afraid as to what size I can make them before performance issues crop up for the game especially for mobile? Is there a workaround or am I fine? \$\endgroup\$
    – Jacob Neal
    Commented Jul 26, 2015 at 21:38
  • \$\begingroup\$ I'm not sure anyone can answer that for you without analyzing your game. There is too many 'if's. There is not really any size limit for the terrain, only resource limits. It depends on the number of vertices used (for terrain and objects), how many textures you are loading, size of textures, etc. That is something you will just have to test against the devices you plan to support. It also depends on how you are rendering the terrain. IE. is it one massive terrain that is always loaded or is it loaded in chunks as the terrain comes within range of the player? \$\endgroup\$ Commented Jul 26, 2015 at 22:29

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .