webgl_lights_physical: Scale seems off

[moraxy]

Description of the problem

The text at the top of webgl_light_physical (master, dev) says

Brick cube is 1 meter in size. Light is 2 meters from floor. Globe is 25 cm in diameter

But the globe is twice the size of the cubes and the light moves from cube-height to 4 * cube-height, so neither ending at nor centered around 2 * cube-height as it suggests.

In early commits the numbers fit(1, 2 and 0.1213), but then the text never got updated it seems (git blame) Is the ratio of 1 unit:1 m still correct here?

Somewhat related: #7636 and #6259 (both about unit scale) and #8260 (original PR)

Three.js version

• Dev
• r98

[Mugen87]

I think the parameters of the geometry generators do not fit to the description:

three.js/examples/webgl_lights_physical.html

Line 221 in 5360a81

var ballGeometry = new THREE.SphereBufferGeometry( 0.5, 32, 32 );

Instead of 0.5 you would have to pass in 0.125 since it's the radius.

three.js/examples/webgl_lights_physical.html

Line 228 in 5360a81

var boxGeometry = new THREE.BoxBufferGeometry( 0.5, 0.5, 0.5 );

The parameters for the box should be all 1. Or you just omit them (since 1 is the default).

However, the example looks a bit odd with such parameters. I would do just this:

var ballGeometry = new THREE.SphereBufferGeometry( 0.25, 32, 32 );

and change the description to:

Brick cube is 50 cm in size.  Globe is 50 cm in diameter.

@moraxy Would you like to do a PR with the change?