3D Modelling/Create 3D Models/AR.js/3D Positions

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Crystal structure of sodium chloride (table salt)
Coordinate System

In the JSON3D4Aframe you can define geometric primitives like

  • boxes,
  • spheres,
  • tubes,
  • cones,
  • planes,
  • triangles,
  • text
  • ...

in the coordinate system (x,y,z) and generate basic 3D models for visualisations. By combination of selected primitives 3D models of create e.g. crystal lattices.

Names for Geometric Primitives[edit]

If your model consists of a large number of geometric primitives it is recommended to provide proper names for the 3D objects. The default 3D model is a water molecule, that consists of 2 white spheres for Hydrogen and 1 red sphere for Oxygen.

Hydrogen 1 (left)
Hydrogen 2 (right)
Oxygen

The webbased tool created for this learning resourc in Wikiversity is JSON3D4Aframe. The tool allow sthe set an individual name/comment for all geometric primitives. Use appropriate names for the spheres.

Blue Sphere X0-Y0-Z0
Green Sphere X1-Y0-Z0
Blue Sphere X1-Y1-Z0
Green Sphere X0-Y1-Z0

Notation: X-right/width, Y-up/height, Z-backward/depth

Coordinates[edit]

For learners it is recommended to play around with the default model of the water molecule:

  • change the xyz-coordinates, e.g.
   0.0 1.0 -4.0
as an triple of x, y, z coordinates.
  • change the size x in direction (radius) of the sphere and
  • place another geometric primitive in the 3D scene by pressing the add-Button in JSON3D4Aframe

Learn to calculate the coordinates of the objects with a spreadsheet document (e.g. in LibreOffice Calc)

External Resources[edit]

See also[edit]