Class DiscreteButtonControl

A button that is considered pressed if the underlying state has a value in the specific range.

Inheritance
Object
InputControl
InputControl<Single>
AxisControl
ButtonControl
DiscreteButtonControl
Inherited Members
Namespace: UnityEngine.InputSystem.Controls
Syntax
public class DiscreteButtonControl : ButtonControl
Remarks

This control is most useful for handling HID-style hat switches. Unlike DpadControl, which by default is stored as a bitfield of four bits that each represent a direction on the pad, these hat switches enumerate the possible directions that the switch can be moved in. For example, the value 1 could indicate that the switch is moved to the left whereas 3 could indicate it is moved up.

[StructLayout(LayoutKind.Explicit, Size = 32)]
internal struct DualShock4HIDInputReport : IInputStateTypeInfo
{
    [FieldOffset(0)] public byte reportId;

    [InputControl(name = "dpad", format = "BIT", layout = "Dpad", sizeInBits = 4, defaultState = 8)]
    [InputControl(name = "dpad/up", format = "BIT", layout = "DiscreteButton", parameters = "minValue=7,maxValue=1,nullValue=8,wrapAtValue=7", bit = 0, sizeInBits = 4)]
    [InputControl(name = "dpad/right", format = "BIT", layout = "DiscreteButton", parameters = "minValue=1,maxValue=3", bit = 0, sizeInBits = 4)]
    [InputControl(name = "dpad/down", format = "BIT", layout = "DiscreteButton", parameters = "minValue=3,maxValue=5", bit = 0, sizeInBits = 4)]
    [InputControl(name = "dpad/left", format = "BIT", layout = "DiscreteButton", parameters = "minValue=5, maxValue=7", bit = 0, sizeInBits = 4)]
    [FieldOffset(5)] public byte buttons1;
}

Fields

maxValue

Value (inclusive) beyond which to stop considering the button to be pressed.

Declaration
public int maxValue
Field Value
Type Description
Int32

minValue

Value (inclusive) at which to start considering the button to be pressed.

Declaration
public int minValue
Field Value
Type Description
Int32
Remarks

minValue is allowed to be larger than maxValue. This indicates a setup where the value wraps around beyond minValue, skips nullValue, and then goes all the way up to maxValue.

For example, if the underlying state represents a circular D-pad and enumerates its 9 possible positions (including null state) going clock-wise from 0 to 8 and with 1 indicating that the D-pad is pressed to the left, then 1, 2, and 8 would indicate that the "left" button is held on the D-pad. To set this up, set minValue to 8, maxValue to 2, and nullValue to 0 (the default).

nullValue

Value at which the button is considered to not be pressed. Usually zero. Some devices, however, use non-zero default states.

Declaration
public int nullValue
Field Value
Type Description
Int32

wrapAtValue

Value (inclusive) at which the values cut off and wrap back around. Considered to not be set if equal to nullValue.

Declaration
public int wrapAtValue
Field Value
Type Description
Int32
Remarks

This is useful if, for example, an enumeration has more bits than are used for "on" states of controls. For example, a bitfield of 4 bits where values 1-7 (i.e. 0001 to 0111) indicate "on" states of controls and value 8 indicating an "off" state. In that case, set nullValue to 8 and wrapAtValue to 7.

writeMode

Determines the behavior of WriteValueIntoState(Single, Void*). By default, attempting to write a DiscreteButtonControl will result in a NotSupportedException.

Declaration
public DiscreteButtonControl.WriteMode writeMode
Field Value
Type Description
DiscreteButtonControl.WriteMode

Methods

FinishSetup()

Declaration
protected override void FinishSetup()
Overrides

ReadUnprocessedValueFromState(Void*)

Declaration
public override float ReadUnprocessedValueFromState(void *statePtr)
Parameters
Type Name Description
Void* statePtr
Returns
Type Description
Single
Overrides

WriteValueIntoState(Single, Void*)

Declaration
public override void WriteValueIntoState(float value, void *statePtr)
Parameters
Type Name Description
Single value
Void* statePtr
Overrides

Extension Methods