Input Polling / Input Controller

One of the basic features a game needs is the control of inputs. And it is not done with just checking which key is pressed or where the mouse is. Most games need much more than just reacting on clicks.

Imagine a combat game, where you allow users to have key-combos for special attacks and animations.

Therefor we provide the easy to use TGorillaInputController component to access keyboard, mouse and gamepad feedbacks. Also in combination!

A HotKey is a configuration inside of the TGorillaInputController, where you define a name and which inputs are necessary to execute a specific action. Those keys use a callback method or can be linked to a Delphi TAction instance.

You are allowed to setup your keys at design- and at runtime.

Because HotKeys were implemented by the TCollection component of Delphi, you can setup your combinations at design time.

1. Drag a TGorillaInputController component onto your form and doubleclick the “HotKeys” property.
2. In the Delphi Collection-Editor you can now add a new TGorillaHotKeyItem.
3. Type in a unique name to identify your hotkey, create a OnTriggered event or attach a TAction component to it.
4. In the next step we should add the input combination by double clicking the “Combinations” property.
5. Here we can now add a new TGorillaHotKeyInputItem.
6. In the item select the “Kind” of device.
7. and add the message input code
8. Repeat it for any further inputs you wish to combine.

uses
  Gorilla.Controller.Input,
  Gorilla.Controller.Input.Consts;
 
procedure TForm1.DoOnHotKey(const AItem : TGorillaHotKeyItem; const ACurrentInput : TGorillaHotKeyRaw);
begin
  DebugOutput(Format('>>> HotKey: %s <<< === %s', [AItem.DisplayName, ACurrentInput.ToString()]));
end;
 
var 
  FInput : TGorillaInputController;
  LHotKey : TGorillaHotKeyItem;
 
  [...]
 
  FInput := TGorillaInputController.Create(Self);
 
  LHotKey := FInput.AddHotKey('TEST1');
  LHotKey.OnTriggered := DoOnHotKey;
  LHotKey.AddInput(TGorillaInputDeviceType.Keyboard, Ord(GORILLA_INPUT_KEY_ALT));
  LHotKey.AddInput(TGorillaInputDeviceType.Keyboard, Ord(GORILLA_INPUT_KEY_C));
  LHotKey.AddInput(TGorillaInputDeviceType.Keyboard, Ord(GORILLA_INPUT_KEY_RETURN));

Besides the HotKey settings the component supports persistent/continuously messages. A persistent message is a continuously notified message from the system and not a temporary message like a click or key-press.

Supported persistent messages are:

You can request those messages at runtime, like in the following code:

var LMPos  : TPoint;
    LMsg   : TGorillaInputMessage;
begin
  // request latest mouse position
  if FInput.GetPersistentMessage(TGorillaInputDeviceType.Mouse, GORILLA_INPUT_MOUSE_POSITION, LMsg) then
  begin
    LMPos := LMsg.Data.AsType<TPoint>();
  end
  else LMPos := TPoint.Zero;
 
  // show mouse position in form caption
  Self.Caption := Format('Gorilla 3D - Mouse: [%d;%d]', [LMPos.X, LMPos.Y]);

All available InputCodes are defined in the Gorilla.Controller.Input.Consts unit.

GORILLA_INPUT_GAMEPAD_TRIGGERS = $100;

GORILLA_INPUT_GAMEPAD_THUMBSTICK_POS_LEFT = $200;
GORILLA_INPUT_GAMEPAD_THUMBSTICK_POS_RIGHT = $201;