# Additive Blending and Gamma Correction

Should one do additive blending (aka lightmapping) in linear space?

I tried doing it in linear space, and it became, well, linear and bland, losing that cool HDR-style bloomy effect. Is there some standard way to do additive blending in linear RGB, or additive blending is now an obsolete gamma space hack and people should forget about it?

• The standard way to do additive blending in linear RGB is to just add two numbers — nothing fancy. If doing that isn't giving you the effect you like, you can use a different blending function. Try showing us an example of the output you have now, and how it differs from the output you want, and we can suggest ways to get closer to your desired effect. – DMGregory Aug 26 '19 at 22:12
• Here I applied a light to a background in gamma and in linear space: imgur.com/M8Lmmje – SmugLispWeenie Aug 26 '19 at 22:19
• If you like the gamma space effect better, then it sounds like you already have a solution. What do you need from us? – DMGregory Aug 26 '19 at 22:19
• Just curious what is the industry standard to apply such lightmaps today, when everything is done in linear space. – SmugLispWeenie Aug 26 '19 at 22:21
• (a^gamma+b^gamma)^(1/gamma) is not equal to (a+b)^(1/gamma) – Ocelot Aug 26 '19 at 22:28