[newbies] How to spawn building like RTS Game

Hi All,

I am currently learning on how to develop a game which required player to select a building and build it on specific location.

This is what I trying to do now.
1) I create a canvas, with a button, which initially plan to act as one of the building type.
2) when player click on the button, set the selected building to a game object.
3) then it should wait for player to click on terrain to get the location clicked.
4) spawn the selected building on the location.

But I have totally no idea on how to do it, youtube and google doesn't inspired me any idea thus.
I am trying to write some script but the "Building" (which is just a cube) is spawn on button area.

Hopefully anyone here can give me some hint about this.

This is my code, which i put in inside a button :-

using UnityEngine;
using System.Collections;

public class BuildingSpawner : MonoBehaviour {

public GameObject spawnObject;
private Vector3 buildingLocation;
private Quaternion buildingRotation;

// Mouse Click event
public void btnBuildingClick()
{
buildingRotation = new Quaternion(0, 0, 0, 0);

Debug.Log(buildingRotation);


getBuildLocation();
Debug.Log(buildingLocation);


if (buildingLocation.x != 0)
{
spawnBuilding();
}
}

// Get build location from mouse click
void getBuildLocation()
{
RaycastHit hit;
Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);

if (Physics.Raycast(ray, out hit, 1000))
{
// Define position to destination
buildingLocation = new Vector3(hit.point.x, hit.point.y, hit.point.z);
Debug.Log(buildingLocation);
}
}

void spawnBuilding()
{
Instantiate(spawnObject, buildingLocation, buildingRotation);
}

}

 

Hey there, welcome to the forums! Whenever you post code please use the CODE tags.

For building instantiation I use something like this (written from memory so it might not compile)

Code (CSharp):

1. //The building prefabs, this is just an array of GameObjects that is set through the inspector.
2. public GameObject[] Buildings;
3.  
4. //This is the layer that the terrain is on
5. public LayerMask acceptableLayer;
6.  
7. //Defines wether we're checking for a valid position
8. private bool currentlyBuilding = false;
9.  
10. //The position at which we'll spawn the building
11. private Vector3 position;
12.  
13. //The building we're currently placing
14. private GameObject currentBuilding;
15.  
16. void Update(){
17.     if(currentlyBuilding){
18.         //Send a ray from the mouse cursor to the terrain and see if it hits
19.         Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
20.         RaycastHit hit = new RaycastHit();
21.      
22.         //We hit the terrain, assign the ray hit position
23.         if(Physics.Raycast(ray, out hit, Mathf.Infinity, acceptableLayer)){
24.             position = hit.point;
25.         }
26.         //We didn't hit the terrain.
27.         else{
28.             position = Vector3.zero;
29.         }
30.      
31.         //If the user presses the left mouse button call SpawnBuilding
32.         if(Input.GetMouseButtonDown(0)){
33.             SpawnBuilding();
34.         }
35.     }
36. }
37.  
38. //The will be called from your UI button.
39. public void AssignBuilding(int buildingIndex){
40.     currentBuilding = Buildings[buildingIndex];
41.     currentlyBuilding = true;
42. }
43.  
44. //Spawn the building if the current position is valid.
45. public void SpawnBuilding(){
46.     if(position != Vector3.zero){
47.         Instantiate(currentBuilding, position, currentBuilding.transform.rotation);
48.     }
49. }

Of course this is very basic, there are a lot of things to look for depending on the environment you're in. Is the building over a river? On a cliff? Do you have enough resources to build it?

Let me know if you have any questions!

 

Hi Ensiferum,

I have studies your code and will give it a try. Your code did gave me some idea too.
Thanks for your feedback ! Let's have some luck blessed on me

 

Did you get it to work ?
I am tryting to figure These things out aswell,
~ Flowered