LuaCAD concepts
These terms apply in every plug-in.
Project
A project groups the drawings of a building. It lives in a folder "number-name" with the project file Projekt.pdata and one folder per discipline, holding one drawing per level. The project palette shows the project of the active drawing as a tree.
Without a project you work in a single drawing – everything works; only functions across several drawings (xrefs of other levels, risers across levels, lists across the project) need a project.
Level and discipline
A level has a name (UG1, EG, OG1 … – basement, ground floor, 1st floor) and elevations. By default the levels are named UG1, EG, OG1, OG2 and DG; drawings that still carry the earlier names (1.OG, UG) still find their level. A discipline is a field of work: architecture, plumbing, heating, ventilation … Each drawing of the project belongs to exactly one level and one discipline – for example "1st floor plumbing". Lists, IFC and annotation use the level of the drawing, not the elevation of a part.
Drawing and xref
In a drawing you see other drawings as an xref: the architecture of the same level, the heating, the pipes of the level below. In the project palette, the check box in front of a drawing attaches it to the active drawing or removes it. Only the active drawing is ever changed – unless LuaCAD explicitly asks (for example when a riser is updated in other levels).
Elevations and reference levels
Every part has an elevation Z above the project zero. You give it as an absolute value or from level using a reference level:
| Reference level | Meaning |
|---|---|
| TOS | top of slab – the structural floor slab |
| FF | finished floor |
| FC | finished ceiling |
| BOS | bottom of slab – the structural slab above |
A system elevation is a named distance from a reference level, the same in every level ("1st elevation" = 15 cm below BOS). By default there are four: 15, 30, 45 and 60 cm below the bottom of structure; you change them in the gear menu › System elevations. Floor-to-floor heights never move anything: if you change the elevations of a level, every part stays where it is; what is displayed is the new distance to the reference level.
Pipes already drawn never follow the system elevations. If you change, rename, delete or add system elevations, every pipe already drawn keeps its elevation and its system elevation – LuaCAD adjusts nothing by itself, so you always know what lies where. New system elevations apply to new pipes. If you query the elevation of a pipe (change elevation, pick elevation, edit riser), LuaCAD shows the system elevation only if a current system elevation lies exactly at that height; otherwise the absolute elevation.
Palette, page and gear menu
Each plug-in works in a palette at the edge of the drawing area. It has pages, an "i" at the top explaining the page, and the gear menu with settings, layers and help. When several plug-ins are open, switch with the plug-in tabs on the left. Palette values only apply to parts you insert from now on – what is already there keeps its values.
Action bar and keys
While a function runs, the action bar at the cursor shows the keys that currently apply – to press or to click. The same key means the same thing in every plug-in (A = distance, R = rotate, D = type an angle, W = pick an angle …). Enter = finish or accept, Esc = cancel. All keys: Reference.
Getting started and insertion help
- Getting started: cards next to the palette that explain a page field by field the first time you open it.
- Insertion help: before special workflows at the cursor, a window with a picture and numbered steps. Only the check box Don't show again hides this help; Close, the cross or Esc close it just this once – it comes back the next time you start the function.
- "i" on pages, dialog boxes and single rows: one sentence, below it "More in the online help". If a value comes from a setting (system, level, system elevation, insulation, templates), the "i" also tells you where to change it – for example "Create or change systems: gear menu › Systems". The reference levels TOS, FF, BOS and FC are written out in the "i" of every list that shows them.
All three can be switched on or off per plug-in in the LuaCAD settings.
System
The system says what flows in a pipe or duct (cold water, heating supply, supply air …). It sets color, layer and the matching catalogs. You manage systems in the gear menu › Systems; each has a short code and a name ("PWC cold water").
Layers
LuaCAD creates its layers itself, for example LuaCAD_SAN_PWC-Kaltwasser – only those that are missing, and an existing layer is never changed. You change name, color, linetype, lineweight and plotting as usual in the layer manager: the assignment is kept and new parts go on the renamed layer. Gear menu › Layers › "Create all layers of this plug-in" creates them all at once, for example for an office template. If a part is on a locked layer, LuaCAD does not change it and tells you so.
Drawing units
The units in which new parts are created are set in the LuaCAD settings or in the gear menu › Drawing units: Automatic (the units of the drawing, GstarCAD command UNITS; without units from the size of the plan) or always mm, cm, dm or m. Inches cannot be chosen yet – a drawing that is itself in inches still gets the right factor with "Automatic". Internally LuaCAD always calculates in mm; fields show the unit next to them. You may calculate in any number field: "600+400" gives 1000.
Where settings are stored
LuaCAD stores settings, templates and systems per user in its own settings store – never in the program folder. The supplied factory parts (symbols, blocks, templates) are in the program folder and are never overwritten; you put your own custom parts and symbols in your library folders. Reset to default settings backs up the settings store first.