Merge pull request #1343 from AdaRoseCannon/transient-input

cabanier · web-flow · commit 47d14b602dd2 · 2023-10-05T12:54:42.000-07:00
Transient intent addition
diff --git a/index.bs b/index.bs
@@ -1826,7 +1826,8 @@ enum XRHandedness {
 enum XRTargetRayMode {
   "gaze",
   "tracked-pointer",
-  "screen"
+  "screen",
+  "transient-pointer"
 };
 
 [SecureContext, Exposed=Window]
@@ -1848,11 +1849,16 @@ The <dfn attribute for="XRInputSource">targetRayMode</dfn> attribute describes t
   - <dfn enum-value for="XRTargetRayMode">gaze</dfn> indicates the target ray will originate at the viewer and follow the direction it is facing. (This is commonly referred to as a "gaze input" device in the context of head-mounted displays.)
   - <dfn enum-value for="XRTargetRayMode">tracked-pointer</dfn> indicates that the target ray originates from either a handheld device or other hand-tracking mechanism and represents that the user is using their hands or the held device for pointing. The orientation of the target ray relative to the tracked object MUST follow platform-specific ergonomics guidelines when available. In the absence of platform-specific guidance, the target ray SHOULD point in the same direction as the user's index finger if it was outstretched.
   - <dfn enum-value for="XRTargetRayMode">screen</dfn> indicates that the input source was an interaction with the canvas element associated with an inline session's output context, such as a mouse click or touch event.
+  - <dfn enum-value for="XRTargetRayMode">transient-pointer</dfn> indicates that the input source was generated as part of an operating system interaction intent rather than a specific piece of hardware. Some examples are user intents based on information too sensitive to expose directly such as gaze, synthesised inputs from web driver or inputs generated by assistive technologies. This should only be used for assistive technologies if it is also used as a primary input so as to not inadvertently indicate that assistive technology is being used as per the W3C design principals.
 
 The <dfn attribute for="XRInputSource">targetRaySpace</dfn> attribute is an {{XRSpace}} that has a [=native origin=] tracking the position and orientation of the preferred pointing ray of the {{XRInputSource}} (along its `-Z` axis), as defined by the {{targetRayMode}}.
 
+For input sources with a {{targetRayMode}} of {{XRTargetRayMode/"transient-pointer"}} the {{targetRaySpace}} represents the ray to the interaction target at the start of the interaction. The pose for this should be static within the gripSpace for this XRInput.
+
 The <dfn attribute for="XRInputSource">gripSpace</dfn> attribute is an {{XRSpace}} that has a [=native origin=] tracking to the pose that should be used to render virtual objects such that they appear to be held in the user's hand. If the user were to hold a straight rod, this {{XRSpace}} places the [=native origin=] at the centroid of their curled fingers and where the `-Z` axis points along the length of the rod towards their thumb. The `X` axis is perpendicular to the back of the hand being described, with the back of the user's right hand pointing towards `+X` and the back of the user's left hand pointing towards `-X`. The `Y` axis is implied by the relationship between the `X` and `Z` axis, with `+Y` roughly pointing in the direction of the user's arm.
 
+For input sources with a {{targetRayMode}} of {{XRTargetRayMode/"transient-pointer"}} the {{gripSpace}} should be the associated user gesture if there is one, otherwise it should be another space the user controls such as the ViewerSpace or the gripSpace or the targetRaySpace of another XRInput. This is to allow user the user to still manipulate the targetRaySpace.
+
 The {{gripSpace}} MUST be `null` if the input source isn't inherently trackable such as for input sources with a {{targetRayMode}} of {{XRTargetRayMode/"gaze"}} or {{XRTargetRayMode/"screen"}}.
 
 The <dfn attribute for="XRInputSource">profiles</dfn> attribute is a [=/list=] of [=input profile name=]s indicating both the prefered visual representation and behavior of the input source.
@@ -1944,7 +1950,13 @@ When an [=XR input source=] |source| for {{XRSession}} |session| has its [=prima
 Transient input {#transient-input}
 ---------------
 
-Some [=/XR device=]s may support <dfn>transient input sources</dfn>, where the [=XR input source=] is only meaningful while performing a <dfn>transient action</dfn>, either the [=primary action=] for a [=primary input source=], or a device-specific <dfn>auxiliary action</dfn> for an [=auxiliary input source=]. An example would be mouse, touch, or stylus input against an {{XRSessionMode/"inline"}} {{XRSession}}, which MUST produce a transient {{XRInputSource}} with a {{targetRayMode}} set to {{screen}}, treated as a [=primary action=] for the [=primary pointer=], and as a non-primary [=auxiliary action=] for a non-primary pointer. [=Transient input sources=] are only present in the session's [=list of active XR input sources=] for the duration of the [=transient action=].
+Some [=/XR device=]s may support <dfn>transient input sources</dfn>, where the [=XR input source=] is only meaningful while performing a <dfn>transient action</dfn>, either the [=primary action=] for a [=primary input source=], or a device-specific <dfn>auxiliary action</dfn> for an [=auxiliary input source=].
+
+One example would be mouse, touch, or stylus input against an {{XRSessionMode/"inline"}} {{XRSession}}, which MUST produce a transient {{XRInputSource}} with a {{targetRayMode}} set to {{screen}}, treated as a [=primary action=] for the [=primary pointer=], and as a non-primary [=auxiliary action=] for a non-primary pointer.
+
+Another example would be intents from the operating system with input derived from sensitive information that cannot be exposed directly, such as interactions based on gaze. These produce a transient {{XRInputSource}} with a {{targetRayMode}} set to {{transient-pointer}}, treated as a [=primary action=].
+
+[=Transient input sources=] are only present in the session's [=list of active XR input sources=] for the duration of the [=transient action=].
 
 [=Transient input sources=] follow the following sequence when handling [=transient actions=] instead of the algorithms for non-transient [=primary actions=]:
 
