Car acceleration using Xbox 360 triggers?

Question

After looking at these links

http://wiki.unity3d.com/index.php?title=Xbox360Controller http://docs.unity3d.com/Documentation/ScriptReference/KeyCode.html

I noticed there is a direct way to enable those triggers on a 360 controller, or anything of similar nature. They are Six Axis or something for Right Trigger, and Fifth Axis for Left Trigger...on the Mac. Regardless, on Windows, they mix up the "Nth Axis" inputs, so Windows and Mac are different.

But I just need to know how do you call these here because it tells me error CS0029: Cannot implicitly convert type `float' to bool' ? Lines highlighted down below in bold.

Let's say it was this script:

   bool accelKey = Input.GetKey (KeyCode.UpArrow);
         float accelKey2 = Input.GetAxis ("6th axis (Joysticks)");
         bool brakeKey = Input.GetKey (KeyCode.DownArrow);
         float brakeKey2 = Input.GetAxis ("5th axis (Joysticks)");
         
         if (drivetrain.automatic && drivetrain.gear == 0)
         {
             accelKey = Input.GetKey (KeyCode.DownArrow);
             accelKey2 = Input.GetAxis("5th axis (Joysticks)");
             brakeKey = Input.GetKey (KeyCode.UpArrow);
             brakeKey2 = Input.GetAxis("6th axis (Joysticks)");
         }
         
         if (Input.GetKey (KeyCode.LeftShift))
         {
             throttle += Time.deltaTime / throttleTime;
             throttleInput += Time.deltaTime / throttleTime;
         }
         else if (accelKey)
         {
             if (drivetrain.slipRatio < 0.10f)
                 throttle += Time.deltaTime / throttleTime;
             else if (!tractionControl)
                 throttle += Time.deltaTime / throttleTimeTraction;
             else
                 throttle -= Time.deltaTime / throttleReleaseTime;
 
             if (throttleInput < 0)
                 throttleInput = 0;
             throttleInput += Time.deltaTime / throttleTime;
             brake = 0;
         }
         
         **else if (accelKey2)**
         {
             if (drivetrain.slipRatio < 0.10f)
                 throttle += Time.deltaTime / throttleTime;
             else if (!tractionControl)
                 throttle += Time.deltaTime / throttleTimeTraction;
             else
                 throttle -= Time.deltaTime / throttleReleaseTime;
 
             if (throttleInput < 0)
                 throttleInput = 0;
             throttleInput += Time.deltaTime / throttleTime;
             brake = 0;
         }
         
         else 
         {
             if (drivetrain.slipRatio < 0.2f)
                 throttle -= Time.deltaTime / throttleReleaseTime;
             else
                 throttle -= Time.deltaTime / throttleReleaseTimeTraction;
         }
         throttle = Mathf.Clamp01 (throttle);
 
         if (brakeKey)
         {
             if (drivetrain.slipRatio < 0.2f)
                 brake += Time.deltaTime / throttleTime;
             else
                 brake += Time.deltaTime / throttleTimeTraction;
             throttle = 0;
             throttleInput -= Time.deltaTime / throttleTime;
         }
         
         
         **if (brakeKey2)**
         {
             if (drivetrain.slipRatio < 0.2f)
                 brake += Time.deltaTime / throttleTime;
             else
                 brake += Time.deltaTime / throttleTimeTraction;
             throttle = 0;
             throttleInput -= Time.deltaTime / throttleTime;
         }
         
         else 
         {
             if (drivetrain.slipRatio < 0.2f)
                 brake -= Time.deltaTime / throttleReleaseTime;
             else
                 brake -= Time.deltaTime / throttleReleaseTimeTraction;
         }
         brake = Mathf.Clamp01 (brake);
         throttleInput = Mathf.Clamp (throttleInput, -1, 1);
                 
         // Handbrake
         handbrake = Mathf.Clamp01 ( handbrake + (Input.GetKey (KeyCode.Space)? Time.deltaTime: -Time.deltaTime) );
         
         // Gear shifting
         float shiftThrottleFactor = Mathf.Clamp01((Time.time - lastShiftTime)/shiftSpeed);
         drivetrain.throttle = throttle * shiftThrottleFactor;
         drivetrain.throttleInput = throttleInput;
         
         if(Input.GetKeyDown(KeyCode.R))
         {
             lastShiftTime = Time.time;
             drivetrain.ShiftUp ();
         }
         if(Input.GetKeyDown(KeyCode.F))
         {
             lastShiftTime = Time.time;
             drivetrain.ShiftDown ();
         }
 
         // Apply inputs
         foreach(Wheel w in wheels)
         {
             w.brake = brake;
             w.handbrake = handbrake;
             w.steering = steering;
         }
     }

Answer 1

Hello,

If we take a look at if statements, we can always express:

 if (condition)

to be the same thing as

 if (condition == True)

Going by this example, lets take a look at your code:
Looking at the lines with the error, we can see that you are checking:

 if (brakeKey2)

Which is (according to our previous definition) the same as

 if (brakeKey2 == True)

If we read the error, it looks like you are trying to convert a float type object to a bool type object (which you can't do).
So we take a look at the definition for brakeKey2 (as it's the only variable on that line):

 float brakeKey2 = Input.GetAxis(/*etc*/)

It is, as expected, a floating point variable.
The simple fact remains, is that you are trying to do something like 8.65 == True. How do you compare a float and a bool?
You can't.

What you need to do is write an expression that evaluates into a bool.
For instance:

 brakeKey2 == 0.0f

or

 brakeKey2 < 0.1 && brakeKey2 > -0.1

of maybe?

 !float.isNull(brakeKey2)

Now your if statement is getting a boolean value and not a float.

Hope this helps, :)
Benproductions1

Car acceleration using Xbox 360 triggers?

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