Websites can have a canvas for 2D graphics and or canvas for 3D graphics ; we can have as many canvases as we want..
For 2d - html5 canvas is the programming toolbox for 2d:
var 2dctx = document.getContext("2d");
For 3d - webgl is the programming toolbox for 3d:
var 3dctx = document.getContext("webgl");
ThreeJS (Three.js) is a programmer toolbox
to make webgl easier.
Construct 3 has it's own 2D and 3D canvases that work together which the Scirra team implemented.
This MakeIt3D Plugin; makes a new 3D Canvas to overlay above both of Construct 3 canvases.. which:
Hidencod (MakeIt3D plugin developer) implemented.
The 3D camera aspect is mainly matrix calculations on the numerical data of 3d graphics;
A perspective projection matrix:
is a mathematically calculated shape to provide a shrinking at the horizon effect also a disappearing from the front and back effect that is used with the calculations of the numerical data of 3d graphics.
How do I know all this?
Because tried to implement threejs functionality without a plugin prior to using this with html files and function calls within construct 3 project and it was very painful..