◆ scrollable()

TextField & MayaFlux::Portal::Forma::TextField::scrollable	(	FormaTarget	in_buf,
		Surface &	surface,
		Scrollable &	scroller,
		std::shared_ptr< Portal::Text::PressParams >	in_params,
		std::string	initial_text = `{}`,
		float	content_multiplier = `3.F`
	)

Fluent creator: place this field inside an already-placed Scrollable, growing itself taller than its viewport and track()ing itself in, wired to scroll past a fixed clip.

scroller is entirely the caller's: build and configure it first - Scrollable::place(), and optionally indicator()/background_color()/ wheel_speed(), all fluent - then pass it here by reference. This method reads scroller.bounds() for the viewport region, places this field at a content region content_multiplier times that viewport's height (top-aligned, same width), and calls scroller.track() with this field's own buf as clip_buf and reposition() as the reflow callback. The same three-call composition shown in the class doc, done once here so callers building the common single-field case do not have to repeat it - nothing about the viewport, its buffer, or any indicator passes through this call, because Scrollable already owns all of that.

Also wires scroller.wheel_handler() onto this field's own element: the field sits on top of the viewport and is added to the Layer after it, so it hit-tests first, and Context::handle_scroll only ever dispatches to the topmost element under the cursor - without this, the wheel would do nothing while the cursor sits directly over the field's own text instead of the viewport's empty margin.

Also relate()s element_id under scroller.viewport_id, so Portal::Forma::destroy(surface, element_id) tears down the scroller's viewport too, even though scroller itself is never owned or stored here - only its Layer-side element needs freeing this way.

Parameters

in_buf	Pre-created target for the field's text.
surface	Surface to register the field's element on - must be the same Surface scroller was placed on.
scroller	Already-placed Scrollable to grow and track into.
in_params	Shared render params. A default-constructed one is allocated if null.
initial_text	Starting text. Cursor starts at its end.
content_multiplier	Content height as a multiple of scroller's viewport height. Default 3x: enough headroom to type past the viewport before hitting the limit, not so much that most content sits unreachable below a near-empty field.

Returns: *this, with results populated.

Definition at line 249 of file TextField.cpp.

{
    const Kinesis::AABB2D viewport = scroller.bounds();
    const Kinesis::AABB2D content_bounds {
        .min = glm::vec2(viewport.min.x, viewport.max.y - viewport.height() * content_multiplier),
        .max = glm::vec2(viewport.max.x, viewport.max.y)
    };
 
    place(std::move(in_buf), surface, content_bounds, std::move(in_params), std::move(initial_text));
 
    TextField field = *this;
    scroller.track(
        surface.layer(), element_id, content_bounds,
        [field](Kinesis::AABB2D shifted) mutable { field.reposition(shifted); },
        buf);
 
    surface.layer().relate(element_id, scroller.viewport_id);
    surface.ctx().on_scroll(element_id, scroller.wheel_handler(surface));
 
    return *this;
}

Referenced by MayaFlux::Portal::Forma::create_text_field().

Here is the call graph for this function:

Here is the caller graph for this function: