Amphtml: [Story 360] Gyroscope default heading

[processprocess]

When gyroscope is enabled, default to the heading-end value.

pitch should always be natural. The ground should always be beneath the user in the experience.

cc @ampproject/wg-stories

[newmuis]

Glad to see you're considering this 😃

This should be reset on page navigation, not on load, I think? Otherwise, you're not guaranteed to be looking in the correct direction when you actually navigate to the page.

[t0mg]

The new scene-heading attribute could possibly solve this, or more precisely the new this.renderer_.setImageOrientation we introduced for it. We could update image orientation when starting the gyro, offsetting the scene heading by the current heading read by the sensor.

[processprocess]

The new scene-heading attribute could possibly solve this, or more precisely the new this.renderer_.setImageOrientation we introduced for it. We could update image orientation when starting the gyro, offsetting the scene heading by the current heading read by the sensor.

100%
I think you did most of the work this in #30138 :)
Thanks so much Tom!

[t0mg]

BTW, shouldn't we use heading-end if provided, instead of heading-start ? When an animation is provided it's likely that the point of interest is at the end, besides it would be less jarring if the gyro is enabled afterwards. WDYT?

[processprocess]

I agree it's safe to assume heading-end is the point of interest. Good call.