using System;
using System.Runtime.InteropServices;
using Unity.Collections.LowLevel.Unsafe;
using UnityEngine.InputSystem.Controls;
using UnityEngine.InputSystem.Layouts;
using UnityEngine.InputSystem.LowLevel;
using UnityEngine.InputSystem.Utilities;
using UnityEngine.Profiling;
////TODO: property that tells whether a Touchscreen is multi-touch capable
////TODO: property that tells whether a Touchscreen supports pressure
////TODO: add support for screen orientation
////TODO: touch is hardwired to certain memory layouts ATM; either allow flexibility or make sure the layouts cannot be changed
////TODO: startTimes are baked *external* times; reset touch when coming out of play mode
////REVIEW: where should we put handset vibration support? should that sit on the touchscreen class? be its own separate device?
namespace UnityEngine.InputSystem.LowLevel
{
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1028:EnumStorageShouldBeInt32", Justification = "byte to correspond to TouchState layout.")]
[Flags]
internal enum TouchFlags : byte
{
// NOTE: Leaving the first 4 bits for native.
IndirectTouch = 1 << 0,
PrimaryTouch = 1 << 4,
Tap = 1 << 5,
// Indicates that the touch that established this primary touch has ended but that when
// it did, there were still other touches going on. We end the primary touch when the
// last touch leaves the screen.
OrphanedPrimaryTouch = 1 << 6,
}
////REVIEW: add timestamp directly to touch?
///
/// State layout for a single touch.
///
///
/// This is the low-level memory representation of a single touch, i.e the
/// way touches are internally transmitted and stored in the system. To update
/// touches on a , s containing
/// TouchStates are sent to the screen.
///
///
///
// IMPORTANT: Must match TouchInputState in native code.
[StructLayout(LayoutKind.Explicit, Size = kSizeInBytes)]
public struct TouchState : IInputStateTypeInfo
{
internal const int kSizeInBytes = 56;
///
/// Memory format tag for TouchState.
///
/// Returns "TOUC".
///
public static FourCC Format => new FourCC('T', 'O', 'U', 'C');
///
/// Numeric ID of the touch.
///
/// Numeric ID of the touch.
///
/// While a touch is ongoing, it must have a non-zero ID different from
/// all other ongoing touches. Starting with
/// and ending with or ,
/// a touch is identified by its ID, i.e. a TouchState with the same ID
/// belongs to the same touch.
///
/// After a touch has ended or been canceled, an ID can be reused.
///
///
[InputControl(displayName = "Touch ID", layout = "Integer", synthetic = true)]
[FieldOffset(0)]
public int touchId;
///
/// Screen-space position of the touch in pixels.
///
/// Screen-space position of the touch.
///
[InputControl(displayName = "Position")]
[FieldOffset(4)]
public Vector2 position;
///
/// Screen-space motion delta of the touch in pixels.
///
/// Screen-space movement delta.
///
[InputControl(displayName = "Delta")]
[FieldOffset(12)]
public Vector2 delta;
///
/// Pressure-level of the touch against the touchscreen.
///
/// Pressure of touch.
///
/// The core range for this value is [0..1] with 1 indicating maximum pressure. Note, however,
/// that the actual value may go beyond 1 in practice. This is because the system will usually
/// define "maximum pressure" to be less than the physical maximum limit the hardware is capable
/// of reporting so that to achieve maximum pressure, one does not need to press as hard as
/// possible.
///
///
[InputControl(displayName = "Pressure", layout = "Axis")]
[FieldOffset(20)]
public float pressure;
///
/// Radius of the touch print on the surface.
///
/// Touch extents horizontally and vertically.
///
/// The touch radius is given in screen-space pixel coordinates along X and Y centered in the middle
/// of the touch. Note that not all screens and systems support radius detection on touches so this
/// value may be at default for an otherwise perfectly valid touch.
///
///
[InputControl(displayName = "Radius")]
[FieldOffset(24)]
public Vector2 radius;
///
/// value of the touch.
///
/// Current .
///
[InputControl(name = "phase", displayName = "Touch Phase", layout = "TouchPhase", synthetic = true)]
[InputControl(name = "press", displayName = "Touch Contact?", layout = "TouchPress", useStateFrom = "phase")]
[FieldOffset(32)]
public byte phaseId;
[InputControl(name = "tapCount", displayName = "Tap Count", layout = "Integer")]
[FieldOffset(33)]
public byte tapCount;
// Not currently used, but still needed in this struct for padding,
// as il2cpp does not implement FieldOffset.
[FieldOffset(34)]
byte displayIndex;
[InputControl(name = "indirectTouch", displayName = "Indirect Touch?", layout = "Button", bit = 0, synthetic = true)]
[InputControl(name = "tap", displayName = "Tap", layout = "Button", bit = 5)]
[FieldOffset(35)]
public byte flags;
// Wasting four bytes in the name of alignment here. Need the explicit fields as il2cpp doesn't respect
// the explicit field offsets.
[FieldOffset(36)]
internal int padding;
// NOTE: The following data is NOT sent by native but rather data we add on the managed side to each touch.
///
/// Time that the touch was started. Relative to Time.realTimeSinceStartup.
///
/// Time that the touch was started.
///
/// This is set automatically by and does not need to be provided
/// by events sent to the touchscreen.
///
///
///
[InputControl(displayName = "Start Time", layout = "Double", synthetic = true)]
[FieldOffset(40)]
public double startTime; // In *external* time, i.e. currentTimeOffsetToRealtimeSinceStartup baked in.
///
/// The position where the touch started.
///
/// Screen-space start position of the touch.
///
/// This is set automatically by and does not need to be provided
/// by events sent to the touchscreen.
///
///
[InputControl(displayName = "Start Position", synthetic = true)]
[FieldOffset(48)]
public Vector2 startPosition;
///
/// Get or set the phase of the touch.
///
/// Phase of the touch.
///
public TouchPhase phase
{
get => (TouchPhase)phaseId;
set => phaseId = (byte)value;
}
public bool isNoneEndedOrCanceled => phase == TouchPhase.None || phase == TouchPhase.Ended ||
phase == TouchPhase.Canceled;
public bool isInProgress => phase == TouchPhase.Began || phase == TouchPhase.Moved ||
phase == TouchPhase.Stationary;
///
/// Whether TODO
///
/// Whether the touch is the first TODO
///
/// This flag will be set internally by . Generally, it is
/// not necessary to set this bit manually when feeding data to Touchscreens.
///
public bool isPrimaryTouch
{
get => (flags & (byte)TouchFlags.PrimaryTouch) != 0;
set
{
if (value)
flags |= (byte)TouchFlags.PrimaryTouch;
else
flags &= (byte)~TouchFlags.PrimaryTouch;
}
}
internal bool isOrphanedPrimaryTouch
{
get => (flags & (byte)TouchFlags.OrphanedPrimaryTouch) != 0;
set
{
if (value)
flags |= (byte)TouchFlags.OrphanedPrimaryTouch;
else
flags &= (byte)~TouchFlags.OrphanedPrimaryTouch;
}
}
public bool isIndirectTouch
{
get => (flags & (byte)TouchFlags.IndirectTouch) != 0;
set
{
if (value)
flags |= (byte)TouchFlags.IndirectTouch;
else
flags &= (byte)~TouchFlags.IndirectTouch;
}
}
public bool isTap
{
get => (flags & (byte)TouchFlags.Tap) != 0;
set
{
if (value)
flags |= (byte)TouchFlags.Tap;
else
flags &= (byte)~TouchFlags.Tap;
}
}
///
public FourCC format => Format;
///
/// Return a string representation of the state useful for debugging.
///
/// A string representation of the touch state.
public override string ToString()
{
return $"{{ id={touchId} phase={phase} pos={position} delta={delta} pressure={pressure} radius={radius} primary={isPrimaryTouch} }}";
}
}
///
/// Default state layout for touch devices.
///
///
/// Combines multiple pointers each corresponding to a single contact.
///
/// Normally, TODO (sending state events)
///
/// All touches combine to quite a bit of state; ideally send delta events that update
/// only specific fingers.
///
/// This is NOT used by native. Instead, the native runtime always sends individual touches ()
/// and leaves state management for a touchscreen as a whole to the managed part of the system.
///
[StructLayout(LayoutKind.Explicit, Size = MaxTouches * TouchState.kSizeInBytes)]
internal unsafe struct TouchscreenState : IInputStateTypeInfo
{
///
/// Memory format tag for TouchscreenState.
///
/// Returns "TSCR".
///
public static FourCC Format => new FourCC('T', 'S', 'C', 'R');
///
/// Maximum number of touches that can be tracked at the same time.
///
/// Maximum number of concurrent touches.
public const int MaxTouches = 10;
///
/// Data for the touch that is deemed the "primary" touch at the moment.
///
///
/// This touch duplicates touch data from whichever touch is deemed the primary touch at the moment.
/// When going from no fingers down to any finger down, the first finger to touch the screen is
/// deemed the "primary touch". It stays the primary touch until released. At that point, if any other
/// finger is still down, the next finger in is
///
/// Having this touch be its own separate state and own separate control allows actions to track the
/// state of the primary touch even if the touch moves from one finger to another in .
///
[InputControl(name = "primaryTouch", displayName = "Primary Touch", layout = "Touch", synthetic = true)]
[InputControl(name = "primaryTouch/tap", usage = "PrimaryAction")]
// Add controls compatible with what Pointer expects and redirect their
// state to the state of touch0 so that this essentially becomes our
// pointer control.
// NOTE: Some controls from Pointer don't make sense for touch and we "park"
// them by assigning them invalid offsets (thus having automatic state
// layout put them at the end of our fixed state).
[InputControl(name = "position", useStateFrom = "primaryTouch/position")]
[InputControl(name = "delta", useStateFrom = "primaryTouch/delta")]
[InputControl(name = "pressure", useStateFrom = "primaryTouch/pressure")]
[InputControl(name = "radius", useStateFrom = "primaryTouch/radius")]
[InputControl(name = "press", useStateFrom = "primaryTouch/phase", layout = "TouchPress", synthetic = true, usages = new string[0])]
[FieldOffset(0)]
public fixed byte primaryTouchData[TouchState.kSizeInBytes];
internal const int kTouchDataOffset = TouchState.kSizeInBytes;
[InputControl(layout = "Touch", name = "touch", displayName = "Touch", arraySize = MaxTouches)]
[FieldOffset(kTouchDataOffset)]
public fixed byte touchData[MaxTouches * TouchState.kSizeInBytes];
public TouchState* primaryTouch
{
get
{
fixed(byte* ptr = primaryTouchData)
return (TouchState*)ptr;
}
}
public TouchState* touches
{
get
{
fixed(byte* ptr = touchData)
return (TouchState*)ptr;
}
}
public FourCC format => Format;
}
}
namespace UnityEngine.InputSystem
{
///
/// Indicates where in its lifecycle a given touch is.
///
public enum TouchPhase
{
///
/// No activity has been registered on the touch yet.
///
///
/// A given touch state will generally not go back to None once there has been input for it. Meaning that
/// it generally indicates a default-initialized touch record.
///
None,
///
/// A touch has just begun, i.e. a finger has touched the screen.. Only the first touch input in any given touch will have this phase.
///
Began,
///
/// An ongoing touch has changed position.
///
Moved,
///
/// An ongoing touch has just ended, i.e. the respective finger has been lifted off of the screen. Only the last touch input in a
/// given touch will have this phase.
///
Ended,
///
/// An ongoing touch has been cancelled, i.e. ended in a way other than through user interaction. This happens, for example, if
/// focus is moved away from the application while the touch is ongoing.
///
Canceled,
///
/// An ongoing touch has not been moved (not received any input) in a frame.
///
///
/// This phase is not used by . This means that will not generally
/// return this value for . It is, however, used by .
///
Stationary,
}
///
/// A multi-touch surface.
///
///
/// Touchscreen is somewhat different from most other device implementations in that it does not usually
/// consume input in the form of a full device snapshot but rather consumes input sent to it in the form
/// of events containing a each. This is unusual as
/// uses a memory format different from . However, when a Touchscreen
/// sees an event containing a , it will handle that event on a special code path.
///
/// This allows Touchscreen to decide on its own which control in to store
/// a touch at and to perform things such as tap detection (see and
/// ) and primary touch handling (see ).
///
///
///
/// // Create a touchscreen device.
/// var touchscreen = InputSystem.AddDevice<Touchscreen>();
///
/// // Send a touch to the device.
/// InputSystem.QueueStateEvent(touchscreen,
/// new TouchState
/// {
/// phase = TouchPhase.Began,
/// // Must have a valid, non-zero touch ID. Touchscreen will not operate
/// // correctly if we don't set IDs properly.
/// touchId = 1,
/// position = new Vector2(123, 234),
/// // Delta will be computed by Touchscreen automatically.
/// });
///
///
///
/// Note that this class presents a fairly low-level touch API. When working with touch from script code,
/// it is recommended to use the higher-level API instead.
///
[InputControlLayout(stateType = typeof(TouchscreenState), isGenericTypeOfDevice = true)]
[Scripting.Preserve]
public class Touchscreen : Pointer, IInputStateCallbackReceiver
{
///
/// Synthetic control that has the data for the touch that is deemed the "primary" touch at the moment.
///
/// Control tracking the screen's primary touch.
///
/// This touch duplicates touch data from whichever touch is deemed the primary touch at the moment.
/// When going from no fingers down to any finger down, the first finger to touch the screen is
/// deemed the "primary touch". It stays the primary touch until the last finger is released.
///
/// Note that unlike the touch from which it originates, the primary touch will be kept ongoing for
/// as long as there is still a finger on the screen. Put another way,
/// of primaryTouch will only transition to once the last finger
/// has been lifted off the screen.
///
public TouchControl primaryTouch { get; private set; }
///
/// Array of all s on the device.
///
/// All s on the screen.
///
/// By default, a touchscreen will allocate 10 touch controls. This can be changed
/// by modifying the "Touchscreen" layout itself or by derived layouts. In practice,
/// this means that this array will usually have a fixed length of 10 entries but
/// it may deviate from that.
///
public ReadOnlyArray touches { get; private set; }
///
/// The touchscreen that was added or updated last or null if there is no
/// touchscreen connected to the system.
///
/// Current touch screen.
public new static Touchscreen current { get; internal set; }
///
public override void MakeCurrent()
{
base.MakeCurrent();
current = this;
}
///
protected override void OnRemoved()
{
base.OnRemoved();
if (current == this)
current = null;
}
///
protected override void FinishSetup()
{
base.FinishSetup();
primaryTouch = GetChildControl("primaryTouch");
// Find out how many touch controls we have.
var touchControlCount = 0;
foreach (var child in children)
if (child is TouchControl)
++touchControlCount;
// Keep primaryTouch out of array.
Debug.Assert(touchControlCount >= 1, "Should have found at least primaryTouch control");
if (touchControlCount >= 1)
--touchControlCount;
// Gather touch controls into array.
var touchArray = new TouchControl[touchControlCount];
var touchIndex = 0;
foreach (var child in children)
{
if (child == primaryTouch)
continue;
if (child is TouchControl control)
touchArray[touchIndex++] = control;
}
touches = new ReadOnlyArray(touchArray);
}
// Touch has more involved state handling than most other devices. To not put touch allocation logic
// in all the various platform backends (i.e. see a touch with a certain ID coming in from the system
// and then having to decide *where* to store that inside of Touchscreen's state), we have backends
// send us individual touches ('TOUC') instead of whole Touchscreen snapshots ('TSRC'). Using
// IInputStateCallbackReceiver, Touchscreen then dynamically decides where to store the touch.
//
// Also, Touchscreen has bits of logic to automatically synthesize the state of controls it inherits
// from Pointer (such as "/press").
//
// NOTE: We do *NOT* make a effort here to prevent us from losing short-lived touches. This is different
// from the old input system where individual touches were not reused until the next frame. This meant
// that additional touches potentially had to be allocated in order to accomodate new touches coming
// in from the system.
//
// The rationale for *NOT* doing this is that:
//
// a) Actions don't need it. They observe every single state change and thus will not lose data
// even if it is short-lived (i.e. changes more than once in the same update).
// b) The higher-level Touch (EnhancedTouchSupport) API is provided to
// not only handle this scenario but also give a generally more flexible and useful touch API
// than writing code directly against Touchscreen.
protected new unsafe void OnNextUpdate()
{
Profiler.BeginSample("Touchscreen.OnNextUpdate");
////TODO: early out and skip crawling through touches if we didn't change state in the last update
//// (also obsoletes the need for the if() check below)
var statePtr = currentStatePtr;
var touchStatePtr = (TouchState*)((byte*)statePtr + stateBlock.byteOffset + TouchscreenState.kTouchDataOffset);
for (var i = 0; i < touches.Count; ++i, ++touchStatePtr)
{
// Reset delta.
if (touchStatePtr->delta != default)
InputState.Change(touches[i].delta, Vector2.zero);
// Reset tap count.
// NOTE: We are basing this on startTime rather than adding on end time of the last touch. The reason is
// that to do so we would have to add another record to keep track of timestamps for each touch. And
// since we know the maximum time that a tap can take, we have a reasonable estimate for when a prior
// tap must have ended.
if (touchStatePtr->tapCount > 0 && InputState.currentTime >= touchStatePtr->startTime + s_TapTime + s_TapDelayTime)
InputState.Change(touches[i].tapCount, (byte)0);
}
var primaryTouchState = (TouchState*)((byte*)statePtr + stateBlock.byteOffset);
if (primaryTouchState->delta != default)
InputState.Change(primaryTouch.delta, Vector2.zero);
if (primaryTouchState->tapCount > 0 && InputState.currentTime >= primaryTouchState->startTime + s_TapTime + s_TapDelayTime)
InputState.Change(primaryTouch.tapCount, (byte)0);
Profiler.EndSample();
}
///
/// Called whenever a new state event is received.
///
///
protected new unsafe void OnStateEvent(InputEventPtr eventPtr)
{
// If it's not a single touch, just take the event state as is (will have to be TouchscreenState).
if (eventPtr.stateFormat != TouchState.Format)
{
InputState.Change(this, eventPtr);
return;
}
// We don't allow partial updates for TouchStates.
if (eventPtr.IsA())
return;
Profiler.BeginSample("TouchAllocate");
// For performance reasons, we read memory here directly rather than going through
// ReadValue() of the individual TouchControl children. This means that Touchscreen,
// unlike other devices, is hardwired to a single memory layout only.
var stateEventPtr = StateEvent.From(eventPtr);
var statePtr = currentStatePtr;
var currentTouchState = (TouchState*)((byte*)statePtr + touches[0].stateBlock.byteOffset);
var primaryTouchState = (TouchState*)((byte*)statePtr + primaryTouch.stateBlock.byteOffset);
var touchControlCount = touches.Count;
// Native does not send a full TouchState as we define it here. We have added some fields
// that we store internally. Make sure we don't read invalid memory here and copy only what
// we got.
TouchState newTouchState;
if (stateEventPtr->stateSizeInBytes == TouchState.kSizeInBytes)
{
newTouchState = *(TouchState*)stateEventPtr->state;
}
else
{
newTouchState = new TouchState();
UnsafeUtility.MemCpy(UnsafeUtility.AddressOf(ref newTouchState), stateEventPtr->state, stateEventPtr->stateSizeInBytes);
}
// Make sure we're not getting thrown off by noise on fields that we don't want to
// pick up from input.
newTouchState.tapCount = 0;
newTouchState.isTap = false;
////REVIEW: The logic in here makes us inherently susceptible to the ordering of the touch events in the event
//// stream. I believe we have platforms (Android?) that send us touch events finger-by-finger (or touch-by-touch?)
//// rather than sorted by time. This will probably screw up the logic in here.
// If it's an ongoing touch, try to find the TouchState we have allocated to the touch
// previously.
var phase = newTouchState.phase;
if (phase != TouchPhase.Began)
{
var touchId = newTouchState.touchId;
for (var i = 0; i < touchControlCount; ++i)
{
if (currentTouchState[i].touchId == touchId)
{
// Preserve primary touch state.
var isPrimaryTouch = currentTouchState[i].isPrimaryTouch;
newTouchState.isPrimaryTouch = isPrimaryTouch;
// Compute delta if touch doesn't have one.
if (newTouchState.delta == default)
newTouchState.delta = newTouchState.position - currentTouchState[i].position;
// Accumulate delta.
newTouchState.delta += currentTouchState[i].delta;
// Keep start time and position.
newTouchState.startTime = currentTouchState[i].startTime;
newTouchState.startPosition = currentTouchState[i].startPosition;
// Detect taps.
var isTap = newTouchState.isNoneEndedOrCanceled &&
(eventPtr.time - newTouchState.startTime) <= s_TapTime &&
////REVIEW: this only takes the final delta to start position into account, not the delta over the lifetime of the
//// touch; is this robust enough or do we need to make sure that we never move more than the tap radius
//// over the entire lifetime of the touch?
(newTouchState.position - newTouchState.startPosition).sqrMagnitude <= s_TapRadiusSquared;
if (isTap)
newTouchState.tapCount = (byte)(currentTouchState[i].tapCount + 1);
else
newTouchState.tapCount = currentTouchState[i].tapCount; // Preserve tap count; reset in OnCarryStateForward.
// Update primary touch.
if (isPrimaryTouch)
{
if (newTouchState.isNoneEndedOrCanceled)
{
////REVIEW: also reset tapCounts here when tap delay time has expired on the touch?
newTouchState.isPrimaryTouch = false;
// Primary touch was ended. See if there are still other ongoing touches.
var haveOngoingTouch = false;
for (var n = 0; n < touchControlCount; ++n)
{
if (n == i)
continue;
if (currentTouchState[n].isInProgress)
{
haveOngoingTouch = true;
break;
}
}
if (!haveOngoingTouch)
{
// No, primary was the only ongoing touch. End it.
if (isTap)
TriggerTap(primaryTouch, ref newTouchState, eventPtr);
else
InputState.Change(primaryTouch, newTouchState, eventPtr: eventPtr);
}
else
{
// Yes, we have other touches going on. Make the primary touch an
// orphan and wait until the other touches are released.
var newPrimaryTouchState = newTouchState;
newPrimaryTouchState.phase = TouchPhase.Moved;
newPrimaryTouchState.isOrphanedPrimaryTouch = true;
InputState.Change(primaryTouch, newPrimaryTouchState, eventPtr: eventPtr);
}
}
else
{
// Primary touch was updated.
InputState.Change(primaryTouch, newTouchState, eventPtr: eventPtr);
}
}
else
{
// If it's not the primary touch but the touch has ended, see if we have an
// orphaned primary touch. If so, end it now.
if (newTouchState.isNoneEndedOrCanceled && primaryTouchState->isOrphanedPrimaryTouch)
{
var haveOngoingTouch = false;
for (var n = 0; n < touchControlCount; ++n)
{
if (n == i)
continue;
if (currentTouchState[n].isInProgress)
{
haveOngoingTouch = true;
break;
}
}
if (!haveOngoingTouch)
{
primaryTouchState->isOrphanedPrimaryTouch = false;
InputState.Change(primaryTouch.phase, (byte)TouchPhase.Ended);
}
}
}
if (isTap)
{
// Make tap button go down and up.
//
// NOTE: We do this here instead of right away up there when we detect the touch so
// that the state change notifications go together. First those for the primary
// touch, then the ones for the touch record itself.
TriggerTap(touches[i], ref newTouchState, eventPtr);
}
else
{
InputState.Change(touches[i], newTouchState, eventPtr: eventPtr);
}
Profiler.EndSample();
return;
}
}
// Couldn't find an entry. Either it was a touch that we previously ran out of available
// entries for or it's an event sent out of sequence. Ignore the touch to be consistent.
Profiler.EndSample();
return;
}
// It's a new touch. Try to find an unused TouchState.
for (var i = 0; i < touchControlCount; ++i, ++currentTouchState)
{
// NOTE: We're overwriting any ended touch immediately here. This means we immediately overwrite even
// if we still have other unused slots. What this gives us is a completely predictable touch #0..#N
// sequence (i.e. touch #N is only ever used if there are indeed #N concurrently touches). However,
// it does mean that we overwrite state aggressively. If you are not using actions or the higher-level
// Touch API, be aware of this!
if (currentTouchState->isNoneEndedOrCanceled)
{
newTouchState.delta = Vector2.zero;
newTouchState.startTime = eventPtr.time;
newTouchState.startPosition = newTouchState.position;
// Make sure we're not picking up noise sent from native.
newTouchState.isPrimaryTouch = false;
newTouchState.isOrphanedPrimaryTouch = false;
newTouchState.isTap = false;
// Tap counts are preserved from prior touches on the same finger.
newTouchState.tapCount = currentTouchState->tapCount;
// Make primary touch, if there's none currently.
if (primaryTouchState->isNoneEndedOrCanceled)
{
newTouchState.isPrimaryTouch = true;
InputState.Change(primaryTouch, newTouchState, eventPtr: eventPtr);
}
InputState.Change(touches[i], newTouchState, eventPtr: eventPtr);
Profiler.EndSample();
return;
}
}
// We ran out of state and we don't want to stomp an existing ongoing touch.
// Drop this touch entirely.
// NOTE: Getting here means we're having fewer touch entries than the number of concurrent touches supported
// by the backend (or someone is simply sending us nonsense data).
Profiler.EndSample();
}
void IInputStateCallbackReceiver.OnNextUpdate()
{
OnNextUpdate();
}
void IInputStateCallbackReceiver.OnStateEvent(InputEventPtr eventPtr)
{
OnStateEvent(eventPtr);
}
unsafe bool IInputStateCallbackReceiver.GetStateOffsetForEvent(InputControl control, InputEventPtr eventPtr, ref uint offset)
{
// This code goes back to the trickery we perform in OnStateEvent. We consume events in TouchState format
// instead of in TouchscreenState format. This means that the input system does not know how the state in those
// events correlates to the controls we have.
//
// This method is used to give the input system an offset based on which the input system can compute relative
// offsets into the state of eventPtr for controls that are part of the control hierarchy rooted at 'control'.
if (!eventPtr.IsA() || StateEvent.From(eventPtr)->stateFormat != TouchState.Format)
return false;
// The only controls we can read out from a TouchState event are those that are part of TouchControl
// (and part of this Touchscreen).
var touchControl = control.FindInParentChain();
if (touchControl == null || touchControl.parent != this)
return false;
// We could allow *any* of the TouchControls on the Touchscreen here. We'd simply base the
// offset on the TouchControl of the 'control' we get as an argument.
//
// However, doing that would mean that all the TouchControls would map into the same input event.
// So when a piece of code like in InputUser goes and cycles through all controls to determine ones
// that have changed in an event, it would find that instead of a single touch position value changing,
// all of them would be changing from the same single event.
//
// For this reason, we lock things down to the primaryTouch control.
if (touchControl != primaryTouch)
return false;
offset = touchControl.stateBlock.byteOffset;
return true;
}
// We can only detect taps on touch *release*. At which point it acts like a button that triggers and releases
// in one operation.
private static void TriggerTap(TouchControl control, ref TouchState state, InputEventPtr eventPtr)
{
////REVIEW: we're updating the entire TouchControl here; we could update just the tap state using a delta event; problem
//// is that the tap *down* still needs a full update on the state
// We don't increase tapCount here as we may be sending the tap from the same state to both the TouchControl
// that got tapped and to primaryTouch.
// Press.
state.isTap = true;
InputState.Change(control, state, eventPtr: eventPtr);
// Release.
state.isTap = false;
InputState.Change(control, state, eventPtr: eventPtr);
}
internal static float s_TapTime;
internal static float s_TapDelayTime;
internal static float s_TapRadiusSquared;
}
}