Light intensity confusion

[jwwalker]

I notice that if you set the intensity of a spot light in lumens, and then call getIntensity, you get a different number back, apparently the original number divided by pi? Is that a bug, or some subtlety I'm not aware of?

[romainguy]

It's a question of luminous intensity vs power but the documentation doesn't match the behavior. Either should document what we actually return or return the original value.

@bejado Could you fix this please?

[bejado]

Where is the documentation wrong?

For Type::SPOT, LightManager.setIntensity sets the luminous power of the light. LightManager.getIntensity returns the luminous intensity. Equation 61 explains the relationship and the pi term.

[bejado]

Oh I see, getIntensity has lumen listed as the unit of intensity, which should be candela.

[romainguy]

We may want to add more details to the docs: setIntensity does mention the luminous power in lumen, and getIntensity the luminous intensity in lumen. It might be helpful if we defined those two terms.