NassScript — Complete Documentation JavaScript console built into NASSCAD · V4.2.6 · NassLab 2026

NassScript is the JavaScript console built into NASSCAD. It gives full access to every global function of the 3D engine — primitive creation, CSG operations, transforms, colors, camera, and more. Scripts run via new Function() in NASSCAD's global context and natively support await (automatic AsyncFunction wrapping).

Everything documented here is plain JavaScript. All NASSCAD variables and functions are accessible directly — no prefix required.

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// Console access

Click ⚡ Script in the menu bar — the modal window opens.

• Paste or type your JavaScript code in the text area
• Run with ▶ Run or Ctrl+Enter
• Navigate through the last 20 executions with Ctrl+↑ / Ctrl+↓ (history cached in RAM + sessionStorage)
• Tab inserts 2 spaces. Scripts natively support await — NASSCAD automatically wraps them in an async function

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// Global variables

These variables are readable (and sometimes writable) from any script.

Variable	Type	Description
objs	Array	Array of all scene objects. Each object contains {id, name, type, mesh, color, isHole, genType?, genParams?}
selObjs	Array	Sub-array of selected objects. Most functions operate on the last element — selObjs[selObjs.length-1]
isHoleMode	Boolean	Global creation mode. true = new primitives are created as holes (red, semi-transparent)
objCnt	Number	Auto-incrementing counter used to name objects. Do not modify manually.
COL	Array<String>	Palette of 10 rotating hex colors: ['#4488cc','#44aa44','#ddaa22','#cc4444','#9966cc',...]
scene	THREE.Scene	The Three.js scene — direct access if you need low-level control
camA	Object	Orbital camera parameters: {theta, phi, dist} — dist max: 1600 mm
camT	THREE.Vector3	Camera target point (orbit center)
_camDirty	Boolean	Set to true to force a 3D re-render + dimension canvas redraw
alignMode	Boolean	Indicates whether alignment mode is active

Object structure

// NASSCAD object structure in objs[]
{
  id:        3,                              // unique identifier
  name:      'Cube_3',                    // display name in the object list
  type:      'cube',                      // 'cube','sphere','cylinder','csg', etc.
  mesh:      THREE.Mesh,                     // direct access to the Three.js mesh
  color:     '#4488cc',                   // hex color
  isHole:    false,                       // true = CSG hole
  genType:   'tore',                      // optional — advanced generator type
  genParams: { R:34, r:5.3, N:64, M:32 }  // optional — generator params
}

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// addPrimitive() sync

Creates a 3D primitive, places it on the grid (y=0) using spiral auto-placement to avoid collisions, and selects it. Respects the global isHoleMode.

Valid values for type

Default size is 20 mm (PS = 20). To resize, use setDim() or set mesh.scale directly after creation.

// Create a cube
addPrimitive('cube');

// Create a sphere as a hole
isHoleMode = true;
addPrimitive('sphere');
isHoleMode = false;   // back to solid mode

// Get the object just created
addPrimitive('cylinder');
const myObj = objs[objs.length - 1];

---

// selObj() sync

Selects an object. If add=false, clears the current selection first. If add=true, adds to the current selection (equivalent to Shift+click).

Parameter	Type	Description
obj	Object	A NASSCAD object (element of objs[])
add	Boolean	false = exclusive selection · true = add to selection

// Select the first object
selObj(objs[0], false);

// Select by name
const target = objs.find(o => o.name === 'Cube_1');
if(target) selObj(target, false);

// Select all spheres
objs.filter(o => o.type === 'sphere').forEach((o, i) => selObj(o, i > 0));

// selectAllObjs() sync

Selects all objects in the scene at once. Equivalent to Ctrl+A. Updates the Properties panel and object list.

// Select everything and run a CSG union
selectAllObjs();
await doCSG('union');

// Equivalent direct assignment
selObjs = [...objs];
updProps(); updOList();

// setHoleMode() sync

Switches selected objects between Solid and Hole mode. Also updates the global isHoleMode if no object is selected (changes the creation mode).

// Switch all spheres to holes
objs.filter(o => o.type === 'sphere').forEach(o => {
  selObjs = [o];
  setHoleMode(true);
});

// delSel() sync

Deletes all selected objects. Pushes an Undo snapshot before deletion. Disposes Three.js geometry and material (frees GPU memory). Clears the _csgTree and BVH cache.

// dupSel() sync

Duplicates selected objects. Copies are offset by +10 mm in X and Z. CSG geometry is independently cloned (no shared references).

// Duplicate + reposition manually
addPrimitive('cube');
dupSel();
const copy = objs[objs.length - 1];
copy.mesh.position.x = 50;
copy.mesh.updateMatrixWorld(true);
_camDirty = true;

---

// setTr() sync

Modifies position, rotation, or scale of the selected object. Automatically handles ground anchoring for the Y axis. Invalidates the BVH cache.

Parameter	Values	Description
property	'position' · 'rotation' · 'scale'	Property to modify
axis	'x' · 'y' · 'z'	Target axis
value	Number (mm or °)	Value in mm (position/scale) or degrees (rotation)

setTr('position', 'x', 30);
setTr('position', 'z', -20);
setTr('position', 'y', 15);  // lift 15 mm off ground
setTr('rotation', 'y', 45);   // 45° around Y

// setDim() sync

Resizes the selected object along the given world axis (AABB), in millimeters. Handles rotated objects via world-axis → local-axis mapping. Automatically repositions on the ground for the Y axis.

addPrimitive('cube');
setDim('x', 50);
setDim('y', 30);
setDim('z', 40);

// recenterCG() sync

Recenters the geometry origin on the real center of gravity (centroid of the mesh). The object's visual position is unchanged — only the internal geometry offset is corrected. Useful before CSG or export when the origin must be centered. Pushes an Undo snapshot.

// Center origin of selected object on its CG
selObj(objs[0], false);
recenterCG();

// dropToGround() sync

Snaps the selection to the ground plane (Y=0) — adjusts position.y so that the lowest point of the bounding box exactly touches Y=0. Works on multi-selection. Pushes an Undo snapshot.

// Drop all objects to the ground at once
selectAllObjs();
dropToGround();

---

// setCol() · setOpa() · setWire() sync

setCol('#ff4444');   // bright red
setOpa(0.5);          // 50% transparent
setWire();             // toggle wireframe

// Direct material access (more flexible)
const o = objs[0];
o.mesh.material.color.set('#22aaff');
o.mesh.material.metalness = 0.8;
o.mesh.material.roughness = 0.1;
_camDirty = true;

// toggleXRay() sync

Toggles X-Ray mode — all objects become semi-transparent with depth-write disabled. Reveals hidden and interior geometry. Same as the 👁 X-Ray toolbar button.

toggleXRay();  // enable X-Ray
await delay(2000);
toggleXRay();  // restore normal view

// renameObj() sync

Renames the last selected object. Syncs the _csgTree (updates all parent nodes that reference this object by name). Pushes Undo. No-op if the name is unchanged.

selObjs = [objs[0]];
renameObj('MyBase');

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// doCSG() async — await required

Runs a CSG Boolean operation on selected objects via the Manifold WASM engine. Creates a new result object and removes the sources.

Parameter	Values	Description
op	'union' · 'subtract' · 'intersect'	'union' — merges N objects into one 'subtract' — subtracts Hole objects from the first Solid 'intersect' — keeps only the volume common to all

// Union of all scene objects
selObjs = [...objs];
await doCSG('union');

// Cube drilled by a sphere (auto-subtract)
addPrimitive('cube');
setDim('x', 40); setDim('y', 40); setDim('z', 40);

isHoleMode = true;
addPrimitive('sphere');
setDim('x', 30);
isHoleMode = false;

selObjs = [...objs];
await doCSG('union');   // becomes subtract automatically

---

// Tore.Gen — Ultra-HD Torus

Parametric watertight torus. Periodic topology (i+1)%N · (j+1)%M — no seam, no edge, fully Manifold WASM compatible.

DOM field	Parameter	Description
tore-sr	R (mm)	Ring radius (center → tube center). Default: 34.0
tore-st	r (mm)	Tube radius. Must be < R. Default: 5.3
tore-sn	N	Ring facets (12–256). Default: 64
tore-sm	M	Tube facets (6–128). Default: 32

showToreDialog();
document.getElementById('tore-sr').value = 50;
document.getElementById('tore-vr').textContent = '50.0';
document.getElementById('tore-st').value = 12;
document.getElementById('tore-vt').textContent = '12.0';
document.getElementById('tore-sn').value = 128;
document.getElementById('tore-vn').textContent = '128';
document.getElementById('tore-sm').value = 64;
document.getElementById('tore-vm').textContent = '64';
_toreRebuild();
await delay(200);
_toreToScene();

// Pipe.Gen — Hollow pipe

Hollow 3-segment pipe with bends. Bishop frame algorithm (parallel transport) + tangent circular arcs — zero section twist. Watertight manifold.

DOM ID	Parameter	Description
pipe-re	Outer radius (mm)	Overall section radius. Default: 5.0
pipe-ep	Wall thickness (mm)	r_int = r_ext − e. Default: 1.2
pipe-rb	Bend radius (mm)	Default: 12.0
pipe-sc	Longitudinal subdiv.	Points on bend arcs. Default: 40
pipe-sr	Radial subdiv.	Circular section facets. Default: 16
pipe-l1/l2/l3	Lengths (mm)	Segments 1, 2, 3. Defaults: 30/20/30
pipe-v1y/v1z	Bend 1 Y/Z (°)	Angles after segment 1. Defaults: 90/0
pipe-v2y/v2z	Bend 2 Y/Z (°)	Angles after segment 2. Defaults: 0/45

// L-shaped pipe (90° bend in Y)
showPipeDialog();
document.getElementById('pipe-re').value  = 8;
document.getElementById('pipe-ep').value  = 1.5;
document.getElementById('pipe-rb').value  = 20;
document.getElementById('pipe-l1').value  = 50;
document.getElementById('pipe-v1y').value = 90;
document.getElementById('pipe-l3').value  = 50;
_pipeRebuild();
await delay(300);
_pipeToScene();

// Gear.Gen — Gears & Pulleys

ISO gears (involute profile, α=20°) — spur / helical / herringbone. V-groove pulleys (watertight lathe) and timing pulleys (ExtrudeGeometry). Standard ISO modules (0.5 → 8 mm).

Gear mode

DOM ID	Parameter	Description
_gearModVal	ISO module (mm)	Global variable. Values: 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8. Default: 2
gear-gtype	Profile	'spur' · 'helical' · 'herringbone'
gear-teeth	Tooth count	Integer ≥ 6. Default: 24. Pitch diameter = module × teeth
gear-h	Thickness (mm)	Default: 20
gear-hr	Bore radius (mm)	Shaft hole radius. 0 = no hole. Default: 6.0
gear-tw	Helix angle (°)	For helical/herringbone. Default: 20

// Spur gear m2 z24
showGearDialog();
_gearModVal = 2;
document.getElementById('gear-gtype').value = 'spur';
document.getElementById('gear-teeth').value = 24;
document.getElementById('gear-h').value     = 15;
document.getElementById('gear-hr').value    = 5;
_gearRebuild();
await delay(400);
_gearToScene();

// Cylind.Gen · Cubic.Gen

Truncated cylinder with double chamfer/fillet and chamfered/rounded cube. Both guarantee watertight manifold output.

DOM ID	Cylind.Gen parameter	DOM ID	Cubic.Gen parameter
cc-h	Height H (mm) — default 60	cbc-w	Width X (mm) — default 60
cc-rt	Top radius Rt — default 25	cbc-h	Height Y (mm) — default 60
cc-rb	Bottom radius Rb — default 40	cbc-d	Depth Z (mm) — default 60
cc-ct	Top chamfer — default 5.0	cbc-c	Chamfer/fillet — default 8.0
cc-cb	Bottom chamfer — default 5.0	cbc-seg	Segments 1/2/6/12/24 — default 6
cc-seg	Chamfer segs 1/2/6/12/24/48
cc-n	Cylinder facets 12/16/24/32/64 — default 32

// Cylind.Gen
showCylindDialog();
document.getElementById('cc-h').value  = 80;
document.getElementById('cc-rt').value = 20;
document.getElementById('cc-rb').value = 35;
_ccRebuild(); await delay(200); _ccToScene();

// ArcSphere.Gen — Spherical sector

Spherical sector with configurable opening angle phi (1–360°). Capped with analytically-correct normals at both poles. Manifold-verified.

DOM ID	Parameter	Description
arcsph-r	Radius (mm)	Sphere radius. Default: 20
arcsph-phi	Angle phi (°)	Opening angle 1–360°. Default: 180
arcsph-seg	Segments	Latitude/longitude subdivisions. Default: 32

showArcSphDialog();
document.getElementById('arcsph-r').value   = 30;
document.getElementById('arcsph-phi').value = 270;
_arcSphRebuild(); await delay(200); _arcSphToScene();

// RevSolid.Gen — Revolved solid

Revolved solid (lathe) with arc angle 1–360°. Closed planar caps when angle < 360°. Watertight manifold.

DOM ID	Parameter	Description
rev-arc	Arc angle (°)	Rotation angle 1–360°. Default: 360
rev-seg	Segments	Radial subdivisions. Default: 64

showRevDialog();
document.getElementById('rev-arc').value = 180;
document.getElementById('rev-seg').value = 64;
_revRebuild(); await delay(200); _revToScene();

---

// undoPush() sync

Saves a snapshot of the current state to the Undo stack. 200 levels persisted in IndexedDB via structured clone (TypedArrays native — ~20–50× faster than base64 JSON). The _csgTree is included in each snapshot — Re-run stays coherent after Ctrl+Z. Call this before any destructive modification.

// newProject() sync

Completely clears the scene, resets counters, empties Undo/Redo stacks and IDB journal, clears the CSG Tree and GeometryPool GC. Ideal at the start of a script for a clean slate.

// updStats() · updOList() sync

updStats() updates the Vertices / Faces / Objects counters in the toolbar. updOList() rebuilds the object list in the Objects panel. Always call updOList() after updStats() when you've manually mutated objs[].

// flushPool() sync

Triggers a manual mark-and-sweep GC on the GeometryPool. Frees all orphan geometry slots (objects removed from objs[] but not yet GC'd). Displays freed MB in the Logs console. Same as the ♻ Flush toolbar button.

// Check memory before/after a heavy CSG sequence
flushPool();
await doCSG('union');
flushPool();

---

// Orbital camera

The camera is defined by spherical coordinates (theta, phi, dist) around the target point camT.

Variable	Type	Description
camA.theta	radians	Horizontal angle (azimuth). 0 = front view (Z+). Rotates around Y.
camA.phi	radians	Vertical angle (elevation). 0 = horizontal · π/2 = top view. Default: Math.PI/5
camA.dist	mm	Camera → target distance. Default: 240 mm · min: 5 mm · max: 1600 mm
camT	THREE.Vector3	Target point (orbit center). Default: {0, 0, 0}

// Top view
camA.phi = Math.PI / 2 - 0.01;
updCam(); _camDirty = true;

// Cinematic rotation (8 seconds)
const delay = ms => new Promise(r => setTimeout(r, ms));
let t = 0;
const spin = setInterval(() => {
  camA.theta += 0.015;
  camA.phi = Math.PI / 5 + Math.sin(t) * 0.12;
  camA.dist = 300 + Math.sin(t * 0.7) * 40;
  t += 0.04;
  updCam(); _camDirty = true;
}, 16);
await delay(8000);
clearInterval(spin);

---

// nasLog() sync

Sends a message to the NASSCAD Logs console (📋 Logs button). Available levels:

// delay() async

const delay = ms => new Promise(r => setTimeout(r, ms));

Non-blocking pause — essential for animations and giving the engine breathing room between heavy operations. Declare at the top of your script.

---

// Example: box drilled by a cylinder

60×40×60 mm box with a centered Ø20 mm cylindrical hole.

// ── Drilled box — NassScript V4.2.6 ─────────────────
const delay = ms => new Promise(r => setTimeout(r, ms));

// Clear scene
objs.forEach(o => {
  scene.remove(o.mesh);
  o.mesh.geometry.dispose();
  o.mesh.material.dispose();
});
objs = []; selObjs = []; objCnt = 0;
updOList(); updStats();
nasLog('OK', 'Scene cleared');

// 1. Main box
isHoleMode = false;
addPrimitive('cube');
setDim('x', 60); setDim('y', 40); setDim('z', 60);
nasLog('OK', 'Box 60×40×60 mm');
await delay(200);

// 2. Drill cylinder (Hole mode)
isHoleMode = true;
addPrimitive('cylinder');
setDim('x', 20); setDim('z', 20); setDim('y', 50);
objs[objs.length-1].mesh.position.set(0, -5, 0);
objs[objs.length-1].mesh.updateMatrixWorld(true);
isHoleMode = false;
nasLog('OK', 'Drill Ø20 mm');
await delay(200);

// 3. CSG
selObjs = [...objs];
nasLog('CSG', 'Subtraction…');
await doCSG('union');
nasLog('OK', '✓ Done!');

// Example: hole grid with a loop

100×5×80 mm plate drilled with a 4×3 grid of Ø8 mm holes.

// ── Hole-grid plate — NassScript V4.2.6 ─────────────
const delay = ms => new Promise(r => setTimeout(r, ms));

objs.forEach(o => { scene.remove(o.mesh); o.mesh.geometry.dispose(); o.mesh.material.dispose(); });
objs = []; selObjs = []; objCnt = 0;
updOList(); updStats();

isHoleMode = false;
addPrimitive('cube');
setDim('x', 100); setDim('y', 5); setDim('z', 80);
nasLog('OK', 'Plate created');

const COLS=4, ROWS=3, spacX=20, spacZ=20;
const offX = -(COLS-1)*spacX/2;
const offZ = -(ROWS-1)*spacZ/2;

isHoleMode = true;
for(let r=0; r<ROWS; r++){
  for(let c=0; c<COLS; c++){
    addPrimitive('cylinder');
    const hole = objs[objs.length-1];
    setDim('x',8); setDim('z',8); setDim('y',20);
    hole.mesh.position.set(offX+c*spacX, -8, offZ+r*spacZ);
    hole.mesh.updateMatrixWorld(true);
    await delay(50);
  }
}
isHoleMode = false;
_camDirty = true;

selObjs = [...objs];
nasLog('CSG', `CSG — ${objs.length} objects`);
await doCSG('union');
nasLog('OK', '✓ Drilled plate complete!');

// Official demo: Stellate Crown

Central torus, 6 orbiting spheres, CSG subtraction, cinematic camera rotation.

// ── Stellate Crown — NassScript V4.2.6 ──────────────
const delay = ms => new Promise(r => setTimeout(r, ms));

// 1. Clear
objs.forEach(o => { scene.remove(o.mesh); o.mesh.geometry.dispose(); o.mesh.material.dispose(); });
objs = []; selObjs = []; objCnt = 0;
updOList(); updStats();
nasLog('OK', '🎬 Demo started');

// 2. Central torus R=50 r=12 N=128 M=64
showToreDialog();
['tore-sr','tore-vr'].forEach((id,i)=>document.getElementById(id)[i?'textContent':'value']='50');
['tore-st','tore-vt'].forEach((id,i)=>document.getElementById(id)[i?'textContent':'value']='12');
['tore-sn','tore-vn'].forEach((id,i)=>document.getElementById(id)[i?'textContent':'value']='128');
['tore-sm','tore-vm'].forEach((id,i)=>document.getElementById(id)[i?'textContent':'value']='64');
_toreRebuild(); await delay(300); _toreToScene();
nasLog('OK', 'Central torus placed');
await delay(500);

// 3. 6 orbiting spheres at R=70 mm
const N=6, R_orbit=70;
for(let i=0; i<N; i++){
  const angle = (2*Math.PI*i)/N;
  isHoleMode = false;
  addPrimitive('sphere');
  const o = objs[objs.length-1];
  o.mesh.position.x = Math.cos(angle)*R_orbit;
  o.mesh.position.z = Math.sin(angle)*R_orbit;
  o.mesh.position.y = 8;
  o.mesh.scale.setScalar(0.45);
  o.mesh.updateMatrixWorld(true);
  updStats(); _camDirty = true;
  nasLog('OK', `Sphere ${i+1}/${N}`);
  await delay(300);
}

// 4. Switch spheres to Hole mode
for(let i=1; i<objs.length; i++){
  selObjs = [objs[i]]; setHoleMode(true); await delay(150);
}

// 5. CSG
selObjs = [...objs];
nasLog('CSG', '⚙ Union (auto-subtract)…');
await doCSG('union');
await delay(800);

// 6. Cinematic spin (8 seconds)
nasLog('OK', '🎥 Camera spin…');
let t=0;
const spin = setInterval(()=>{
  camA.theta += 0.015;
  camA.phi = Math.PI/5 + Math.sin(t)*0.12;
  camA.dist = 350 + Math.sin(t*0.7)*40;
  t += 0.04;
  updCam(); _camDirty = true;
}, 16);
await delay(8000);
clearInterval(spin);
nasLog('OK', '🎬 Demo complete!');

---

// Limits & best practices

Rule	Why
Always await doCSG()	doCSG is async (Manifold WASM Worker). Without await, the script continues before the result is ready → objs[] becomes inconsistent
Use delay() between heavy steps	Gives the main thread breathing room — prevents UI freezes
Clear scene at the start of demo scripts	Avoids object collisions and memory bloat
Keep CSG meshes under 50,000 triangles	Above this — risk of Manifold Worker freeze (> 30 seconds)
MEM > 70% → flushPool() then save + reload	The MEM gauge (bottom right) — flushPool() frees orphan slots; page reload frees the full GeometryPool
Call mesh.updateMatrixWorld(true) after each move	Required before any BVH hit-test or bbox calculation
Set _camDirty = true after mutations	Forces Three.js re-render + 2D dimension canvas redraw
Call updOList() after mutating objs[]	Syncs the Objects panel — without it, the list is stale

NassScript Documentation V4.2.6 · NassLab 2026 · CC BY-NC 4.0 · nasscad.com