math pro's anyone? arealight int. with scaling factor

[Sorath]

does my post make any sense..

cause with no decay in arealights it's still a decay in it's depth..

but wouldn't it be cool to have same intensities with different scalings?

[Gal]

drag your light in hypershade, create a multiply node, or a few.. using connection editor connect the outscale of one the axises, like x.. to input of multiply and that is your controller.
what i would do is on your light add new attributes of whatever u want to modify. call it shadow size, intensity of light, color..whatever and make them floats unless it's color. put default value as the default value that u want your light to start with.
now in hypershade u got a multiply or several, their first input is the scale of the light X the other input on each mulitplier will be the new attributes u added. like shadow size
then the output of the multiply connect it to the light's shadow, intensity and etc.
if u dont want the values to be directly multiplied by scale(say scale is from 1-2000) and u only need multiply of 0.1-2..then u can use setrange to compress the ranges of the outputs for each attribute u want it can have a different range, like intensity can be 0.0-3.0, shadow intensity 0.0-1.0 and so on.

[YourDaftPunk]

i'm using one area light with scaling of 1 and intensity of 1.

since i want to plug it's scaling factor in it's intensity to maintain intensity values and therefore beeing able to just adjust shadow softness with it's scaling factor.
i have a little problem with.

scaling = intensity (by eye measuring).
1 = 1
0.5 = 3.9
0.1 = 100
2 = 0.25

what is the math behind it? how can i make a driven key or shading network to maintain intensity with scaling.

Area means squared.

Lets say Base Scale = 1 and Base Intensity = 1 like in your example.

Therefore, we have:
New Intensity = ( Old Scale^2 / New Scale^2 ) * Old Intensity

So if we scale to 0.1 we have in simplified form:
100 = 1 / (0.1*0.1)

or 0.5:
4 = 1 / (0.5*0.5)

and yes we can try scale of 2:
0.25 = 1 / (2*2)

Finally, a more complex example. Start scale is 12 and start intensity is 350. You could scale your light to 30 and find the new intensity like so:
56 = (12^2 / 30^2) * 350
-shawn

[Starrider]

Basically it's just

intensity = 1.0 / (scale ^ 2)

intensity = 1.0 / pow(scale, 2);

edit: oh sorry, same time send out fail :)

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