Rect.Contains not understanding output?

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I'm currently making a marquee selection tool for an RTS which is all but complete I'm just having some funny problems with my box that I can't quite work out. Rect.Contains says that it only checks the X and Y co-ordinates of an object, although my output seems correct the code isn't doing what I am telling it to do, here is the basic code structure.

     if(Input.GetMouseButtonUp(0)) {
             //If the mouse has been raised and there is a unique start point create and end point
             if(start_box != Vector3.zero) {
                 end_box = Input.mousePosition;
                 
                 //Bounding box contains the unique start and end points from the selection
                 //Then creates an array of all selectable objects in the scene
                 boundbox = new Rect(start_box.x, start_box.y, end_box.x-start_box.x, end_box.y+start_box.y);
                 selectedunits = GameObject.FindGameObjectsWithTag("Selectable");
                 for (int i = 0; i < selectedunits.Length; i++) {
                     Vector3 objectlocation = Camera.main.WorldToScreenPoint(new Vector3(selectedunits[i].transform.position.x,selectedunits[i].transform.position.y,selectedunits[i].transform.position.z));
                     print ("Box Size: " + boundbox + " Object Location: " + objectlocation);
                     if(boundbox.Contains(objectlocation)) {
                         selectedunits[i].SendMessage("setisSelected", true);    
                     }
                 }
             }
         }

I also have an on mouse button down that gets the start co-ordinate, these are no problems, my output below is from the print statement of me trying different size boxings only to fail to grab the object......

 Box Size: (x:167.00, y:549.00, width:482.00, height:722.00) Object Location: (361.1, 486.6, 138.8) 
 
 Box Size: (x:222.00, y:578.00, width:271.00, height:958.00) Object Location: (294.8, 322.0, 101.3)
 
 Box Size: (x:222.00, y:578.00, width:271.00, height:958.00) Object Location: (361.1, 486.6, 138.8)

I think I am messing up my y co-ordinate, probably because I have been looking at it too long, I've tried changing the height of the box to both adding the values together and taking them away. I'm wondering if I need to take the screen size into account when dealing with the y variable or something because I think it's backward. In all cases it seems my x value is fine but my y value falls outside the boxes range even though it shouldn't...

Answer 1

Best Answer

Answer by gRntaus · Apr 08, 2013 at 02:42 PM

Decided I would answer my own question.

I was simply calculating the box wrong and was also not taking into consideration the fact that you can box from multiple directions. Just fixed it up then by creating a method to take care of it for me to keep my code cleaner in the update section, the code now does the following:

 private void makeBox() {
         float xmin = Mathf.Min(start_box.x, end_box.x);
         float ymin = Mathf.Min(start_box.y, end_box.y);
         float width = Mathf.Max(start_box.x, end_box.x) - xmin;
         float height = Mathf.Max(start_box.y, end_box.y) - ymin;
         boundbox = new Rect(xmin, ymin, width, height);
     }

Far cleaner and allows me to call it when needed and easily make me the right box.

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Rect.Contains not understanding output?

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