Types

Located in src/lib/ts/types/Interfaces.ts. Two interfaces, both simple.

Projected

What you get after the projection pipeline spits out a vertex.

interface Projected {
  x: number;  // screen X
  y: number;  // screen Y
  z: number;  // depth (NDC)
  w: number;  // clip space W (for culling)
}

Not a quaternion—same letters, different meaning. The w here is the divisor from perspective divide. We keep it to check if vertices are behind the camera (w < 0 → don't draw).

Intentionally not using Point for x, y. It's a pipeline-specific structure, not general geometry.

O_Scene

A thing in the scene graph that can be rendered.

interface O_Scene {
  id: string;
  so: Smart_Object;
  edges: [number, number][];
  faces?: number[][];
  parent?: O_Scene;
  position: vec3;
  color: string;
}

• id — unique identifier, auto-generated.
• so — back-reference to the part this entry draws. The vertex coordinates and the orientation come from the part, not from this entry.
• edges — pairs of vertex indices that define the wireframe.
• faces — optional groups of vertex indices that define filled polygons.
• parent — optional parent entry for hierarchical transforms.
• position — translation in parent space, passed directly to gl-matrix.
• color — CSS color prefix, for example 'rgba(78, 205, 196,'.

Note: vertices are not stored on the entry. They live on the back-referenced part and are read on every projection pass. This keeps geometry edits in one place (the part's bounds, formulas, and rotation).

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Coordinate Types

2D (from Coordinates.ts)

Class	What it's for
Point	2D position (x, y)
Size	2D dimensions (width, height)
Rect	2D rectangle (origin + size)
Polar	Polar coordinates (r, phi)

3D (from Coordinates.ts)

Class	What it's for
Point3	3D position (x, y, z)
Size3	3D dimensions (width, height, depth)
Block	3D box (origin + size)

Usage in Managers

Manager	Type	Field/Param
Render	Size	size (canvas dimensions)
Render	Point3	project_vertex(v)
Camera	Size	init(size)
Input	Point	last_position, T_Handle_Drag(delta)
Scene	Point3[]	create({ vertices })

Point and Size have useful methods (offsetBy, vector_to, dividedInHalf, etc.) that simplify coordinate math. The 3D equivalents follow the same patterns.

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Canvas setup

Gotchas for crisp rendering on Retina displays.

• DPR scaling — canvas buffer = logical size × devicePixelRatio, context scaled by dpr, CSS width/height set to logical pixels
• SO edges — lineWidth: 1, lineCap: square, coordinates snapped to half-pixel grid (Math.round(x) + 0.5)
• Dimensional lines — lineWidth: 0.5 (1 physical pixel on 2× Retina)
• Text — coordinates rounded to integers for crisp glyph placement