Support programmatically changing pan/zoom

[DSteve595]

It would be nice to be able to programmatically manipulate the transformation of the image, initially and over time.
Use cases:

• A comic reader wants to start at the top, probably one of the corners
• A map wants to start viewing a specific location

[nateridderman]

A map wants to start viewing a specific location

💯 this is my use case. This library is awesome, and this issue is the one thing it's missing before I can adopt it in my app.

[saket]

The next release will introduce new APIs for controlling an image's pan and zoom. @nateridderman will this solve your use case?

telephoto/zoomable/src/commonMain/kotlin/me/saket/telephoto/zoomable/ZoomableState.kt

Lines 146 to 190 in f0201b8

	/**
	* Zooms in or out around [centroid] by a ratio of [zoomFactor] relative to the current size,
	* and suspends until it's finished.
	*
	* @param zoomFactor Ratio by which to zoom relative to the current size. For example, a [zoomFactor]
	* of `3f` will triple the *current* zoom level.
	*
	* @param centroid Focal point for this zoom within the content's size. Defaults to the center
	* of the content.
	*
	* @param animationSpec The animation spec to use or [SnapSpec] for no animation.
	*/
	suspend fun zoomBy(
	zoomFactor: Float,
	centroid: Offset = Offset.Unspecified,
	animationSpec: AnimationSpec<Float> = DefaultZoomAnimationSpec,
	)
	/**
	* Zooms in or out around [centroid] to achieve a final zoom level specified by [zoomFactor],
	* and suspends until it's finished.
	*
	* @param zoomFactor Target zoom level for the content. For example, a [zoomFactor] of `3f` will
	* set the content's zoom level to three times its *original* size.
	*
	* @param centroid Focal point for this zoom within the content's size. Defaults to the center
	* of the content.
	*
	* @param animationSpec The animation spec to use or [SnapSpec] for no animation.
	*/
	suspend fun zoomTo(
	zoomFactor: Float,
	centroid: Offset = Offset.Unspecified,
	animationSpec: AnimationSpec<Float> = DefaultZoomAnimationSpec,
	)
	/**
	* Animate pan by [offset] Offset in pixels and suspend until it's finished.
	*
	* @param animationSpec The animation spec to use or [SnapSpec] for no animation.
	*/
	suspend fun panBy(
	offset: Offset,
	animationSpec: AnimationSpec<Offset> = DefaultPanAnimationSpec,
	)