I am working on an L system to generate trees, and my algorithm works fine. I made it so that that the L-System I'm working on displays itself as Line Renderers. The full code is as follows:
public class TransformInfo{
public Vector3 position;
public Quaternion rotation;
}
public class LSystemScript : MonoBehaviour{
[SerializeField] private float iterations;
[SerializeField] private GameObject branch;
[SerializeField] private GameObject leaf;
[SerializeField] private float length;
[SerializeField] private float angle ;
[SerializeField] private float rotationAngle;
[SerializeField] private GameObject treeMesh;
private const string axiom = "X";
private Stack<TransformInfo> transformStack;
private Dictionary<char, string> rules;
private string currentString = string.Empty;
void Start(){
transformStack = new Stack<TransformInfo>();
angle = UnityEngine.Random.Range(10, 60);
iterations = UnityEngine.Random.Range(3, 5);
rotationAngle = UnityEngine.Random.Range(0, 90);
length = UnityEngine.Random.Range(0.01f, 0.1f);
rules = new Dictionary<char, string> {
{ 'X',"[F-[[X]+X]+F[+FX]-X]" },
//{ 'X', "[FX[+F[-FX]FX][-F-FXFX]]" }, //This generates interesting shrubs
{ 'F',"FF"}
};
Generate();
//ReplaceWithMesh();
}
private void ReplaceWithMesh(){
GameObject[] gos = GameObject.FindGameObjectsWithTag("Tree");
foreach (GameObject g in gos) {
Quaternion gq = g.transform.rotation;
Instantiate(treeMesh, new Vector3(g.transform.position.x, g.transform.position.y, g.transform.position.z), gq);
}
}
private void Generate() {
currentString = axiom;
StringBuilder sb = new StringBuilder();
for(int i=0; i < iterations; i++) {
//loop through current string and create a new string based on the rules
foreach (char c in currentString){
sb.Append(rules.ContainsKey(c) ? rules[c] : c.ToString());
}
//Set currentString to the new string we just generated.
currentString = sb.ToString();
sb = new StringBuilder();
}
//foreach (char c in currentString)
for (int c = 0; c < currentString.Length; c++){
switch(currentString[c])
{
case 'F':
//Draw a straight line
Vector3 initialPosition = transform.position;
transform.Translate(Vector3.up * length);
GameObject treeSegment;
if (currentString[(c + 1) % currentString.Length] == 'X' ||
currentString[(c + 3) % currentString.Length] == 'F' && currentString[(c + 4) % currentString.Length] == 'X')
{
treeSegment = Instantiate(leaf);
}
else{
treeSegment = Instantiate(branch);
transform.Rotate(0, rotationAngle, 0);
}
treeSegment.GetComponent<LineRenderer>().SetPosition(0, initialPosition);
treeSegment.GetComponent<LineRenderer>().SetPosition(1, transform.position);
break;
case 'X':
//does nothing, generate more Fs
break;
case '+':
//Rotates clockwise
transform.Rotate(Vector3.back * angle);
break;
case '-':
//Rotates counter-clockwise
transform.Rotate(Vector3.forward * angle);
break;
case '[':
//Save current transform info
transformStack.Push(new TransformInfo(){
position = transform.position,
rotation = transform.rotation
});
break;
case ']':
//Return to our previously saved transform info
TransformInfo ti = transformStack.Pop();
transform.position = ti.position;
transform.rotation = ti.rotation;
break;
default:
throw new InvalidOperationException("Invalid L-tree operation");
}
}
}
}
The next step is to replace the Line Renderer with meshes/prefabs. But nothing I tried seems to be working.
I tried simply replacing the line renderers with meshes, as well as tagging the line prefabs, and using the their tags to get their location and rotation and instantiate prefabs in their place. But that didn't seem to work either.
