c# - Keeping my object from rolling out of the screen -

i using tilt function on phone control object roll left , right. not want roll beyond screen width.

as in simple illustration below, dotted lines represent width of screen. 'o' object , max signs indicate maximum point object allowed roll to.

max--------o--------max

but using code, object still rolls out of screen. tried testing both height n width , ended same result object rolls out of screen. please advice doing wrong. thank you.

public float speed = 10.0f; void update()     {         vector3 dir = vector3.zero;         dir.x = input.acceleration.x;          if (dir.sqrmagnitude > 1)             dir.normalize();          dir *= time.deltatime;          if (!(mathf.round(dir.x) > mathf.round(screen.width/2)) || !(mathf.round(dir.x) < -mathf.round(screen.width/2)))         {             transform.translate(dir * speed);         }      }    **updated  public float speed = 10.0f;     void update()     {         vector3 dir = vector3.zero;         dir.x = input.acceleration.x;          if (dir.sqrmagnitude > 1)             dir.normalize();          dir *= time.deltatime;         //transform.translate(dir * speed);          if (transform.position.x < 0)         {             transform.position = new vector3(0, this.transform.position.y, this.transform.position.z);         }         else if (transform.position.x > screen.width)         {             transform.position = new vector3(screen.width, this.transform.position.y, this.transform.position.z);         }         else         {             transform.translate(dir * speed);         }     } 

i think thereare several ways can go checking transfomrs position.

first off if using 2d camera use method like

leftbounds = camera.x - (camera.pixelwidth/2); 

however because ortho camera angles not set @ particulare size @ x distace camera hard calculate.

i have seen instances coliders on camera outside render rand placed camera children

adding colision mask affect appropriate game object best.