Schlagwort: documentation

The ActionableObjects and the User Input

When the player has focused an object that, or, on that an action can be performed, a menu with the action options is shown. (see last entries)

Overview of the flow of user input to actionable objects

In the character controller, which handles the player input, the event functions in the scene controller for these two actions are registered to event delegates in the character controller.

„The ActionableObjects and the User Input“ weiterlesen

Unity, the Terrain and me, Part 1

This is a very naive approach to the wonderfull world of Unity3D Terrain System.

I played around with it for a long time, did some cool things with it, like on-the-fly bomb craters via script and stuff.

It actually is time now to do this a bit more focused, since I am planing to use it in my game Tanks with Legs. For doing so, I started a laboratory session with Unity3D 2019.

First thing I want and need to do : Take a Mesh and put it on the terrain surface like a coat. I need this for my procedural level generator streetmap generator to make the streets or paths align to the height of the terrain.

But I ran into some problems while doing so and noticed I have to fresh up on a few things. I will do this very slowly and document it here.

Put a grid on the terrain

First thing I want to do is to put a grid of sphers on the terrain, on the same height as their world position on the terrain.

I setup a new GameObject and put a script on it which I named TerrainGridder.

First thing I need to know is which terrain to use, which is done by a public Terrain field so it can be assigned in the inspector.

Now I need to get the pivot world location of the terrain and then the dimensions of the terrain. Since the dimensions in the transform of a terrain is (1/1/1), this is not really usefull.

On a normal GameObject you would use the bounds of the Renderer Component, but since a terrain has no renderer (at least not by default or as component), you can use the size field of the terrainData field of the terrain. This field holds a vector with the dimensions of the terrain in worldScale.

With the method getHeight of the terrainData object of the terrain I can get easily the height of the terrain at a (x/z) world position.

So after using this code : 

   for (int y = 0; y < gridSize; y++)
    {
        float ypos = (terrainDimensionsInWorldScale.y / gridSize) * y;

        for (int x = 0; x < gridSize; x++)
        {
            GameObject sphere = GameObject.CreatePrimitive(PrimitiveType.Sphere);

            float xpos = (terrainDimensionsInWorldScale.x / gridSize) * x;


            sphere.transform.position = new Vector3(xpos, terrainToGrid.terrainData.GetHeight((int)xpos, (int)ypos), ypos);
        }
    }

I have this grid on the terrain :

Grid on Terrain made with my little TerrainGridder script.

But if I change the height of the spheres using the retrieved y height with the terrainData method, it is nor working as excepted :

So what am I doing wrong here ? Let me investigate.

So first of all, it seems that I should use terrain.SampleHeight and not terrain.terrainData.GetHeight.

So with this code : 

    for (int y = 0; y < gridSize; y++)
    {
        float ypos = (terrainDimensionsInWorldScale.z / gridSize) * y;

        for (int x = 0; x < gridSize; x++)
        {
            GameObject sphere = GameObject.CreatePrimitive(PrimitiveType.Sphere);

            float xpos = (terrainDimensionsInWorldScale.x / gridSize) * x;

            sphere.transform.position = new Vector3(xpos, terrainToGrid.SampleHeight(new Vector3(xpos,0,ypos)), ypos);
        }
    }

I get the result I wanted as first step.

The grid of spheres is now perfectly aligned on the y-axis according to the terrain height. With this I can start part two of the TerrainGridder : Taking a mesh and changing the height of its vertices to the height of the terrain.