Spawning random platforms in unity - unity3d

Question

So in my quest to make a game like the very popular zigzag game, I am stuck at randomly generating platforms. The platforms generate randomly in X,-X,Z,-Z directions. I have written my code where it generates the platforms. I might have taken a very long approach (alternative approaches if any)
void Start ()
{
lastPos = platform.transform.position;
size = platform.transform.localScale.x;
InvokeRepeating("SpawnXZ",1f,0.2f);
}
void SpawnX()
{
Vector3 pos = lastPos;
pos.x += size;
lastPos = pos;
Instantiate(platform, pos, Quaternion.identity);
}
void SpawnZ()
{
Vector3 pos = lastPos;
pos.z += size;
lastPos = pos;
Instantiate(platform, pos, Quaternion.identity);
}
void SpawnNegX()
{
Vector3 pos = lastPos;
pos.x -= size;
lastPos = pos;
Instantiate(platform, pos, Quaternion.identity);
}
void SpawnNegZ()
{
Vector3 pos = lastPos;
pos.z -= size;
lastPos = pos;
Instantiate(platform, pos, Quaternion.identity);
}
void SpawnXZ()
{
int rand = Random.Range(0, 6);
if (rand < 3)
{
SpawnX();
}
else if(rand >= 3)
{
SpawnZ();
}
if(--counter == 0) { CancelInvoke("SpawnXZ"); };
if(counter == 0)
{
counter = 25;
int r = Random.Range(0,2);
if(r == 0)
{
InvokeRepeating("SpawnNegXZ",0f,0.2f);
}
else
{
InvokeRepeating("SpawnXNegZ",0f,0.2f);
}
}
}
void SpawnNegXZ()
{
int rand = Random.Range(0, 6);
if (rand < 3)
{
SpawnNegX();
}
else if(rand >= 3)
{
SpawnZ();
}
if(--counter == 0) { CancelInvoke("SpawnNegXZ"); };
if(counter == 0)
{
counter = 25;
int r = Random.Range(0,2);
if(r == 0)
{
InvokeRepeating("SpawnXZ",0f,0.2f);
}
else
{
InvokeRepeating("SpawnNegXNegZ",0f,0.2f);
}
}
}
void SpawnXNegZ()
{
int rand = Random.Range(0, 6);
if (rand < 3)
{
SpawnX();
}
else if(rand >= 3)
{
SpawnNegZ();
}
if(--counter == 0) { CancelInvoke("SpawnXNegZ"); };
if(counter == 0)
{
counter = 25;
int r = Random.Range(0,2);
if(r == 0)
{
InvokeRepeating("SpawnXZ",0f,0.2f);
}
else
{
InvokeRepeating("SpawnNegXNegZ",0f,0.2f);
}
}
}
void SpawnNegXNegZ()
{
int rand = Random.Range(0, 6);
if (rand < 3)
{
SpawnNegX();
}
else if(rand >= 3)
{
SpawnNegZ();
}
if(--counter == 0) { CancelInvoke("SpawnNegXNegZ"); };
if(counter == 0)
{
counter = 25;
int r = Random.Range(0,2);
if(r == 0)
{
InvokeRepeating("SpawnNegXZ",0f,0.2f);
}
else
{
InvokeRepeating("SpawnXNegZ",0f,0.2f);
}
}
}
I have clubbed xz, -xz , x -z and -x -z. I call platform spawning in X and Z direction first, then switching to -XZ or x -Z and so on. But there are 2 main issues.
PS : those small black squares are nothing but diamonds (ignore them).
They either form a 2X2 block or overlap each other.
How do I avoid these? or is there a simpler way of generating platforms that I am missing.

Answer 1

You need an array to indicate which tiles are occupied:
bool[,] tiles = new bool[N,N];
or a dictionary
Dictionary<XZ, bool> tiles = new Dictionary<XZ, bool>();
public struct XZ { public int X; public int Z; }
whenever a tile is spawned check the value to see if it is possible to spawn or not:
void SpawnXZ()
{
int x = (int) (lastpos.x / size);
int z = (int) (lastpos.z / size);
int rand = Random.Range(0, 6);
if (rand < 3 && !tiles[x + 1, z])
{
SpawnX();
tiles[x + 1, z] = true;
}
else if(rand >= 3 && && !tiles[x, z + 1])
{
SpawnZ();
tiles[x, z + 1] = true;
}
else
{
...
}
Note that this code will not work, and it's just a starting point for you to develop it further.