Paraboloid customizable by user. No mirrors, because Three.js has so many versions, subversions and variants that I was not yet able to figure out whic version to use to create a reflective mirror..
Made with BabylonJS
How sun trajectories at solstices and equinox are reflected in spherical mirrors of different diameters:
In the scene there are 3 arcs representing sun trajectories at solstice and equinox:
This 2d simulation shows how reflected rays spread differently depending on mirror radius: the more they spread, the less intense is the reflected light:
The larger is the curvature radius, the bigger appears the sun; but the larger is such radius, the shorter path of the sun is visible in the mirror; so, to have whole sun path visible in a mirror, the curvature radius must be small, but the sun will appear small too. A matrix of small mirror could cover whole sun path, compensating the small appearance by multypling the number of reflections?
It displays in 3d space a paraboloid with one hexagon parallel to each face; ideally the cylinder should be turned into a real reflector capable of reflecting surrounding objects, to simulate how moving sun appears in the mirror.
To do:
- each face currently has two mirrors oriented slightly differently, but only one mirror should be presemt
- "mirrors" are currently just cylinders, they do not reflect
- paraboloid should be modifiable by user (inclination, height, width,...)
- moving sun to be added
- mirrors to be made smaller and denser
First functional version: a paraboloid mesh has been created starting from the embedded BabylonJS function which creates a "Toroidal knot"
Fully functional parabolic mirror simulator:
You can change inclination of the rotation axis of the sun, and change the hour angle of the sun, to see how rays are reflected by the mirror; the mirror itself can be chamged by means of two parameter, but please note that only a simmetrical mirror (i.e. elliptical paraboloid, with a = b) will have a point-shaped focus and will reflect all rays into parallel rays). Symmetric paraboloid, with parallel test rays reflectd into single point:
Non-symmetric paraboloid, reflecting parallel rays into "something else" (catenary?):
