Module waterfall 

The waterfall system: the recent spectrum laid out as a landscape and seen through the shared perspective camera (ADR-0258).

One frame

update reduces the analysis frame’s band array to elements levels, shapes and eases each one through the same helpers the spectrum readout uses (downsample, shape_and_ease), and hands the eased levels to the Landscape. That keeps a ring of past rows and pushes one every row_period seconds of injected dt, so the rows are spaced in time, not in frames, and the landscape scrolls at the same speed at any display rate (ADR-0019).

render lays the rows out on the ground plane: row k of the ring sits at depth (k + frac) * row_spacing behind the front edge, where frac is the fraction of a period since the last push, so every row slides back continuously and a push moves nothing. Each row is a polyline of elements - 1 segments across the frequency axis, height * level tall, clipped and culled through the camera block and drawn by this scene’s own seg3d renderer.

The front edge is live

The nearest row is the live eased level, drawn at depth 0 every frame, not the last pushed row: the front edge answers the music on the frame it arrives, however long row_period is. A pushed row is born on top of it and fades in over its first period as it slides away (alpha = frac), so a push adds no line at once and the front edge never pops. The oldest row fades out over its last period the same way.

Colour

The palette runs along the frequency axis, as on spectrum (ADR-0059): hue places the lowest band and hue_spread says how far the palette travels to the highest. Age dims a row by fade: the farthest row keeps 1 - fade of the front edge’s light.

Solid

When the camera block’s solid is on, every row segment also lays a skirt under itself: a black band down to the ground plane, drawn through the same seg3d pipeline and sorted with its row by where the row stands, so a near row hides what lies behind it — hidden-line removal for a ridgeline (ADR-0263). A skirted row costs twice the segments, and the rows drawn are held to that cost each solid frame, announced as the load-time row clamp is.

Structs

WaterfallConfig

The [waterfall] table, validated (ADR-0180 rule 1).

WaterfallScene

The waterfall scene: the landscape’s rows and the seg3d renderer they are drawn through.

Constants

DEFAULT_ELEMENTS

The bands across a row a preset that names none draws.

DEFAULT_ROWS

The rows a preset that names none draws.

DEFAULT_ROW_PERIOD

The row_period a preset that names none pushes at, in seconds.

MAX_ROWS

The most rows a preset may ask for at load, before the tier’s seg3d_segments holds it further.

MAX_ROW_PERIOD

The longest row_period a preset may ask for, in seconds.

MIN_ROWS

The fewest rows a landscape may ask for: the live front row and one pushed row behind it.

MIN_ROW_PERIOD

The shortest row_period a preset may ask for, in seconds. Below a frame at 100 Hz every frame would push more than one copy of the same row.

PARAMS

Parameter vocabulary — see fragment_field::PARAMS. Keep in sync with set_param below.