Schematic KDL

Glossary

  • Top-level nodes: panel variants, object_3d, line_3d, vector_arrow, window.
  • EQL: expressions are evaluated in the runtime EQL context. Vector-like fields expect 3 components; world_pos is a 7-component array (quat + position).
  • Colors: color r g b [a] or named (black, white, blue, red, orange, yellow, yalk, pink, cyan, gray, green, mint, turquoise, slate, pumpkin, yolk, peach, reddish, hyperblue); alpha optional. Colors can be inline or in color/colour child nodes. Defaults to white when omitted unless noted.

theme

  • Optional top-level node that sets the session UI appearance.
  • mode: "dark" (default) or "light"; drives window decorations and picks the dark/light variant of the color scheme. If a preset does not ship a light variant, the theme stays in dark.
  • scheme: name of a color preset. Built-ins are default, eggplant, catppuccini-macchiato, catppuccini-mocha, catppuccini-latte, and matrix; user presets are picked up from any color_schemes folder in the asset directory or data directory. Unknown names fall back to default. If a user preset shares a name with a built-in, the user version wins. See color-schemes for the file layout.
  • Applies to the whole session; a secondary file can set its own mode for its windows, but the active scheme stays the one from the primary schematic.
  • Controls both egui styling (palette) and the window decoration theme (Dark/Light).

window

  • path/file/name: optional secondary schematic file. Relative paths resolve against the parent schematic directory (or CWD). If absent, the entry configures the primary window instead of loading a secondary file.
  • title/display: optional window title.
  • screen: optional zero-based display index.
  • rect { x y width height }: optional child; four percentages (clamped 0–100). Used for placement of primary or secondary windows. Secondary windows default to DEFAULT_SECONDARY_RECT when unset.

panel containers

  • tabs { ... }: children are panels. No extra props.
  • hsplit / vsplit: children are panels. Child share=<f32> controls the weight within the split. active (bool) is parsed but not currently used. Optional name.

panel content

  • viewport: fov (default 45.0), active (bool, default false), show_grid (default false), show_arrows (default true), hdr (default false), name (optional label), camera pos/look_at (optional EQL). Vector arrows can also be declared directly inside the viewport node; those arrows are treated as part of that viewport’s layer and respect its show_arrows/show_grid settings, allowing you to build a local triad tied to the viewport camera.
  • graph: positional eql (required), name (optional), type (line/point/bar, default line), lock (default false), auto_y_range (default true), y_min/y_max (default 0.0..1.0), child color nodes (optional list; otherwise palette).
  • component_monitor: component_name (required).
  • action_pane: positional label (required), lua script (required).
  • query_table: positional query (defaults to empty), type (eql default, or sql).
  • query_plot: positional label (required), query (required), refresh_interval in ms (default 1000), auto_refresh (default false), color (default white), type (eql default, or sql).
  • inspector, hierarchy, schematic_tree: no properties.
  • dashboard: layout node (Bevy UI style). Key properties: label (optional), display (flex default, or grid/block/none), box_sizing (border-box default or content-box), position_type (relative default or absolute), overflow (per-axis; defaults visible), overflow_clip_margin (visual_box + margin, defaults content-box / 0), sizing (left/right/top/bottom/width/height/min_*/max_* accept auto, px, %, vw, vh, vmin, vmax; default auto), aspect_ratio (optional f32), alignment (align_items/justify_items/align_self/justify_self/align_content/justify_content, all default to default variants), flex (flex_direction, flex_wrap, flex_grow default 0, flex_shrink default 1, flex_basis default auto, row_gap/column_gap default auto), children (nested dashboard nodes), colors via bg/background child (default transparent), text (optional), font_size (default 16), text_color child (default white), spacing via margin/padding/border children with left/right/top/bottom.

object_3d

  • Positional eql: required. Evaluated to a world_pos-like value to place the mesh.

  • Mesh child (required, exactly one):

    • glb: path (required), scale (default 1.0), translate (x,y,z) (default 0s), rotate (deg_x,deg_y,deg_z) in degrees (default 0s).
    • sphere: radius (required); color (default white).
    • box: x, y, z (all required); color (default white).
    • cylinder: radius, height (both required); color (default white).
    • plane: width/depth (default size if set, else 10.0); optional size shorthand; color (default white).
    • ellipsoid: scale (EQL string, default "(1, 1, 1)"), color (default white).

    Mesh nodes support an optional emissivity=<value> property (0.0–1.0) to make the material glow (e.g., sphere radius=0.2 emissivity=0.25 { color yellow }).

line_3d

  • Positional eql: required; expects 3 values (or 7 where the last 3 are XYZ).
  • line_width: default 1.0.
  • color: default white.
  • perspective: default true (set false for screen-space lines).

vector_arrow

  • vector: EQL expression yielding a 3-component vector (required).
  • origin: EQL for arrow base; world_pos or 3-tuple (optional).
  • scale: numeric multiplier (default 1.0).
  • normalize: #true/#false; normalize before scaling (default false).
  • body_frame / in_body_frame: apply origin rotation to the vector (default false).
  • color: arrow color (default white).
  • name: label text; used for legend/overlay (optional).
  • show_name: show/hide overlay label (default true).
  • arrow_thickness: numeric thickness multiplier with 3-decimal precision (default 0.1).
  • label_position: proportionately 0.0–1.0 along the arrow (0=base, 1=tip) for label anchor, or absolutely by specifying a number in a string with an 'm' suffix, .e.g., "0.3m" for 0.3 meters from origin (default "0.1m").

Schema at a glance

Legend: parentheses group alternatives; | means “or”; square brackets [...] are optional; curly braces {...} repeat; * is zero-or-more, + is one-or-more; angle brackets <...> mark positional args.

schematic =
  ( theme
  | window
  | panel
  | object_3d
  | line_3d
  | vector_arrow
  )*

theme = "theme"
      [mode=dark|light]
      [scheme=string]

window = "window"
       [path|file|name=string]
       [title=string]
       [screen=int]
       [rect x y w h]

panel =
  viewport
  | graph
  | component_monitor
  | action_pane
  | query_table
  | query_plot
  | inspector
  | hierarchy
  | schematic_tree
  | dashboard
  | split
  | tabs

split = ("hsplit" | "vsplit")
      [active=bool]
      [name=string]
      { panel [share=float] }+

tabs = "tabs" { panel }+

viewport = "viewport"
         [fov=float]
         [active=bool]
         [show_grid=bool]
         [show_arrows=bool]
         [hdr=bool]
         [name=string]
         [pos=eql]
         [look_at=eql]
         { vector_arrow }

graph = "graph" eql
      [name=string]
      [type=line|point|bar]
      [lock=bool]
      [auto_y_range=bool]
      [y_min=float]
      [y_max=float]
      { color }*

component_monitor = "component_monitor"
                  [component_name=string]

action_pane = "action_pane"
            <label>
            [lua=string]

query_table = "query_table"
            [query=string]
            [type=eql|sql]

query_plot = "query_plot"
           <label>
           [query=string]
           [refresh_interval=ms]
           [auto_refresh=bool]
           [color]
           [type=eql|sql]

inspector      = "inspector"
hierarchy      = "hierarchy"
schematic_tree = "schematic_tree"
dashboard      = "dashboard" { dashboard_node }+

object_3d = "object_3d"
          <eql>
          { glb
          | sphere
          | box
          | cylinder
          | plane
          | ellipsoid
          }
          [emissivity=float]

line_3d = "line_3d"
        <eql>
        [line_width=float]
        [color]
        [perspective=bool]

vector_arrow = "vector_arrow"
             <vector-eql>
             [origin=eql]
             [scale=float]
             [normalize=bool]
             [body_frame|in_body_frame=bool]
             [color]
             [name=string]
             [show_name=bool]
             [arrow_thickness=float]
             [label_position=0..1]

color = "color"
      ( r g b [a]
      | name [alpha]
      )

Examples

Minimal viewport + graph:

theme mode="light" scheme="matrix"

viewport name="Main"
         fov=45.0
         active=#true
         show_grid=#true
         pos="drone.world_pos"
         look_at="(0, 0, 0)"
graph "drone.altitude"
      name="Altitude"
      auto_y_range=#true

Vector arrow with custom color and label:

vector_arrow
  "drone.vel_x,drone.vel_y,drone.vel_z"
  origin="drone.world_pos"
  scale=1.5
  name="Velocity"
  normalize=#true
  body_frame=#true
  arrow_thickness=1.500
  label_position=0.9 {
  color 64 128 255
}
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