Control Systems in Unity

Transcription

1 Unity has an interesting way of implementing controls that may work differently to how you expect but helps foster Unity s cross platform nature. It hides the implementation of these through buttons and axis, which may be confusing but it means you can use the code if(input.getbuttondown( Fire1 ) and with some configuration, it will work the same on every platform. Implementing Xbox controller support The most commonly used controller for PC is the xbox one, this is due in large part to it s blanket compatibility and nice design as well as the endless cheap rip offs. So, that s the one we ll target, if you have another controller, don t worry, the process is largely the same, you ll just have to find the configuration. Xbox controllers in Unity, along with any common controller are automatically recognised and given a standard configuration, Unity maps each button and stick to an axis or button in Unity. This may vary depending on the platform Unity is being hosted on (Windows, Mac or Linux). More details are found here- If you re building cross platform you re slightly more limited, if you re only building for windows, you may want to look at the XInput project, which uses Microsoft s own handler and wraps it for Unity giving you much more precise control, and rumble! The controller, as shown in the picture below is actually split into a number of axis, the left stick is the X and Y axis by default, the right generic 4th and 5 th axis etc. Worth noting is that the triggers, because they are pressure sensitive are actually an axis too, the 3 rd axis. The left trigger goes from -1 to 0 and the right from 0 to 1, meaning if Unity gets -0.5 on the 3 rd axis it knows the left trigger is being pressed about half as hard as it can. Figure 1 - Xbox controller from the Unity3d wiki

2 The way unity works is it gives each Input a name (Axis) e.g. Horizontal, Vertical, button 0, button 1 and then maps an input to that, for instance, horizontal by default is Joystick 1 X axis. Fire1 by default is button 0. The typical example of projects is below, these can be seen via Edit-Project Settings->Input. Adding this to a game setting So, let s add this to a scene, I m going to use the test scene I ve been using for other tutorials, with blocks and capsules. You can use that if you ve been following along or you can use any number of others. The process should be the same. In Unity if you go to edit- project settings -> Input, you ll get the screen to the right. You might notice some (most) of these premade axes are setup twice, for instance horizontal or Fire1. This is because one is setup for keyboard and mouse, one for joysticks/pads you can get info from both at once. Expand Fire1 and take a look, there are a number of areas to take note of: Name Descriptive Name Descriptive Negative Name Negative Button Positive Button Alt Negative Button Alt Positive Button Gravity Dead Sensitivity Snap Invert Type Axis The name of this axis or button used in code and in the launcher. A detailed description of the Positive Button function that is displayed in the game launcher. Same as above but for negative button. The button that will send a negative value to the axis. The button that will send a positive value to the axis. The secondary button that will send a negative value to the axis. The secondary button that will send a positive value to the axis. How fast will the input recenter. Only used when the Type is key / mouse button. Any positive or negative values that are less than this number will register as zero. Useful for joysticks to stop accidental presses. How sensitive the axis is to being touched, larger is faster response time but can be jagged, lower is smoother. If enabled, the axis value will be immediately reset to zero after it receives opposite inputs. Only used when the Type is key / mouse button. If enabled, the positive buttons will send negative values to the axis, and vice versa. Use Key / Mouse Button for any kind of buttons including 0, Mouse Movement for mouse and scrollwheels, Joystick Axis for sticks. Axis of input from the device (joystick, mouse, gamepad, etc.)

3 A lot of information there, it ll make more sense when we actually demonstrate it. Select your player object, the one you want to control. We are going to add some very basic movement scripts to it, the point of this tutorial isn t to explain all the ways of controlling a player, if you already have some movement scripts hopefully you ll be able to modify them using the examples I give. Ensure a character controller is attached to your player, and then create a new script called basicmovement which we ll use to move our character. We set variables for the character controller, the jumpspeed, gravity, yvelocity and movespeed. In Start, we get the CharacterController and save it to varcontroller. In update we get the input from the joystick axis and save it. We get a copy of the rotation of the object. We change the y rotation (left and right) to add our joystick X value times 5. Then set the rotation to our new rotation. We get the H and V values of the horizontal and vertical axis wherever that comes from. Direction is the direction we are going from the input. movespeed. Velocity just times this with the We then check if we re grounded, if we apply some speed upwards and press the jump button we go up, if not we go down. The velocity is then fed back into the transform attached and we move using that velocity vector times by time to even it out independent to how many frames per second you have.

4 The key here is using the Input.GetAxis, this is indepdenent for the most part, whatever input you use, keyboard or gamepad, if you have an axis called Horizontal mapped, it ll work. You may get an error, you need to setup the JoystickX element for the axis. Go to Unity input manager, the same place as before. Right click one of the horizontal or vertical axis for the joypad and click duplicate Array element, change the settings to the ones to the right. The key here is the axis, set it to the 4 th axis to use the right hand analogue stick. You may also want to setup a new button for Jump and assign it to a joystick button, look at how Fire1 is setup and go from there. Dual inputs and switching between them One thing you ll find is that if you plug in two controllers they both work in the same way, this is due to that last little line Get Motion from all Joysticks. We can refine and narrow down this to one particular gamepad relatively easily, so this is what we will do. Back to the input manager, we ll create an axis for joystick1 and an axis for joystick2, I ve simply duplicated JoystickX and called one JoystickX1 and the other JoystickX2, then changed the joystick numbers at the bottom accordingly. Likewise I duplicated the horizontal joystick axis, renamed one to horizontal1 and the other horizontal2 and changed their joystick nums. I ll leave you to do the same to vertical. This gives us a control scheme for joystick1 and a control scheme for joystick2. Now we need to make some changes to our basic movement script to accommodate these. Open it up and; Add a new field, public int playernum under movespeed. Here, we ve just changed the axis from JoystickX in the original, to JoystickX +playernum. This means we add the value of playernum to the end, e.g. if playernum was 1 it would be joystickx1.

5 Clicking on the player object now you get a field for PlayerNum in basic movement, for player 1 enter 1 like below. Try the game, it should move around nicely. This is great, and if you duplicate the capsule you should be able to set on as playernum 1 and another as 2 and use two controllers to move them round. Find the camera attached, adapt the viewport Rect on them to fit the below, this is explained in the previous tutorial for minimaps and cameras. One should have the left hand settings, the other the right. You should now have a nice split screen view, with one on top, one below, try your game and you should be able to navigate around nicely. But wait, what if I want to use a keyboard and controller? This gets a little more confusing but there s a couple ways we could do it, a public field so we directly type the axis name in e.g. JoystickX1 but that s prone to some easy mistakes. Alternatively we create an enum, an enum is a type that lists a certain set of values, so we can make a type for each axis (or the group of axis) and in it have the options, horizontal, horizontal1, horizontal2. Here we have, in the BasicMovement script under the variables three enums. We can then use them as types, above we have the three variables for them, you can see the type is the enum we created below. In each one are the three options for axis to be set to. In the inspector we then get drop downs for the choices we have set so we can only choose the correct axis. Note, enum s don t (easily) allow spaces when we are using them like this. For this reason in Unity s input manager I renamed Mouse X to MouseX without the space. In Update we then use the variable we set at the top, calling tostring to convert it into the string that Unity accepts. Try it! You should be able to set one character to gamepad (using either gamepad 1 or 2) and one to keyboard (using Horizontal, Vertical and MouseX).