How to get the Intensity of Light on Shader?

I'll try to find start value of attenuation each point light or spot light.
Is there any methods to get light intensity on vertex shader or fragment shader?
thanks.

 

Hello, did you manage to solve this? I'm facing the same issue here =)

Thanks

 

Had the same problem. It seems to be included in _LightColor0.

So _LightColor0 does not only give you the color of the light, but the color of the light premultiplied with it's intensity.
To use it, include it with:

uniform float4 _LightColor0; // automaticly from "Lighting.cginc

at the start of your CGPROGRAM (together with your other uniforms like the _MainTex). Then use it like:

float4 color;
float3 colorCalculatedForThisFragment = float3(1,1,1); //just for testing, in reallity you would want to calculate distance and angle.
color.rgb = colorCalculatedForThisFragment * _LightColor0;
color.a = 1;
return color;

Note, unlike many other values, _LightColor0 seem not to be limited between (0,0,0) and (1,1,1) - for a bright yellow light it might end up being something like (5.1, 5.7, 0.0).