如何将游戏对象设置为统一的精确长度

Question

In Unity I have a float that represents a distance

float distance = Vector3.Distance(start.position,end.position);

I want to use that float to change the size of an object along its Z axis. I tried:

gameobject.transform.localScale.z = distance;

However, this just changes the scale, I need to change the game object to an exact length. Is there a straightforward way to achieve this?

Answer 1

I created a workaround function to convert a specific length into a scale (for anyone who may find this question in the future). Game objects can only have their size changed though scale, but their exact size can be found through the renderer. using a little interpolation you can convert this into a new scale to resize your object to an exact size.

public void newScale(GameObject theGameObject, float newSize) {

    float size = theGameObject.GetComponent<Renderer> ().bounds.size.y;

    Vector3 rescale = theGameObject.transform.localScale;

    rescale.y = newSize * rescale.y / size;

    theGameObject.transform.localScale = rescale;

}

Answer 2

Unity has no thing like "Length" for any object. At the scale of (1,1,1) unity considers that every object is of one unit. meaning if you want your object to be 3 units long along z axis you change its scale to (1,1,3) and similarly for other axis. thats why it is said that you need to take special care while designing assets for unity as they all need to made according to unity defined scale.

Answer 3

This solution worked better for me:

public void convertDistanceToScale(GameObject go, float distance){
     Vector2 size = go.transform.lossyScale;
     size.x = distance;
     size.x = (size.x * go.transform.localScale.x) / go.transform.lossyScale.x;
     size.y = go.transform.localScale.y;
     go.transform.localScale = size;
}

This works for all objects I've tested it on, including child objects and rotated objects.

Answer 4

image here

in my case , this object Radius 243.638 at 3dsmax .

image here

but this re-scale cause this is child object . and want fix the width as parent object variable .

image here

    Transform Truck_Area_Range = transform.Find("Circle");
    Mesh mesh = Truck_Area_Range.GetComponent<MeshFilter>().mesh;
    float Mesh_X = mesh.bounds.size.x;
    Debug.Log(Mesh_X); // this same as my 3dsmax Radius * 2
    Vector3 LocalScale = transform.localScale;
    Debug.Log(LocalScale.x); // parent object LocalScale
    float current_size = Mesh_X * LocalScale.x;
    Debug.Log(current_size); // Circle object size in scene
    float distance = 30;
    float newSize = distance / current_size;
    Debug.Log(newSize);  
    Truck_Area_Range.localScale = new Vector3 (newSize, newSize, 1);