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I want a Sphere Gardient on Skysphere

If you know the material from the Skysphere, I have a question, I want to add a Sphere Gardient 2d/3d and to be in same position with the Sun, I don’t want Spheremask, if I have an object between me and the sun, the rays dissapear, how I should do?

basically, I want a Sphere Gardient and the Center should be in sun (Light direction), some ideas?

bump bump bump

Sorry but your post is unclear to me.

You say you want a gradient, and say you don’t want to use sphere gradient 2d/3d. You said something about rays disappearing but you didn’t say what you wanted to happen… what do you mean by rays? is this also talking about lightshafts or some other feature?

If you just want it to render on top of things you can use Disable Depth test on translucent materials.

I would just look at the example BP Skysphere that is included in engine\content. That is how we have done it in the past.

Hi Ryan.

This is my sun:

And I want to become like this:

But the most important THING, I don’t want to change the sun color / brightness, I want a Gardient Sphere added on the Material and moving after sun.
I supposed as I need Sphere Gardient 2d/3d.

Ok so you just want a second, softer glow around the sun.

I would either use the node “Radial Gradient Exponential” or just use a texture and hand paint the gradient using photoshop brushes. “Radial Gradient Exponential” does a spheremask but gives you exponential controls.

Or you could simply try using a “power” on a texture like this from engine:
Texture2D’/Engine/EngineVolumetrics/Fogsheet/Materials/T_EV_FogSheet_Falloff_01.T_EV_FogSheet_Falloff_01’


sunScatter = pow(max(0, dot(sunDir, viewDir)), 8)

http://iquilezles.org/www/articles/fog/fog.htm

That will work if you want to render the material on the whole sky and pay for the cost everywhere. the method I suggested was more about creating a sprite that would be positioned in front of the sun, and it would be cheaper since you’d only pay the cost on the sprite. But you can also position the dot product power version on a plane as well.

If you are rendering skysphere anyway then couple extra ALU won’t affect performance much. This will also add small amount of scatter to whole sun side hemisphere which is subtle but nice effect.

Hi Ryan, I tried your option, I did this:

And looks:

1st problem, isn’t a sphere
2nd problem, how I move it ?

Hi Kalle_H, your method works.

I did:

And looks:

so, which is more faster? (speaking about performance)

GPU’s are ridiculous fast to calculate math nowadays so my method should be very fast because it will not use any textures.