Multiple globe materials makes the globe darker

[ProjectBarks]

Fixes

• Found bug where gamma was being correct on alpha, which had no impact
• Fix that only adjusts gamma once

Notes:

While the gamma is adjusted per each material type I would like to make it so that it is adjusted on the final RGB values.

Screenshots:

Before

After

After with HDR

In reference to: #7726

[cesium-concierge]

Thanks for the pull request @ProjectBarks!

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[lilleyse]

How does this look with HDR enabled? It's important to still have a gamma correct somewhere if HDR is on.

[ProjectBarks]

@lilleyse updated with HDR screenshots

From what I saw, each material applies its own gamma correction so the one I removed was the duplicate in the fusion process. Let me know if that was incorrect.

Here is a sandcastle you can use to test.

[mramato]

@lilleyse does anything else need to happen here?

[lilleyse]

I'll try to check this out later today.

[lilleyse]

From what I saw, each material applies its own gamma correction so the one I removed was the duplicate in the fusion process. Let me know if that was incorrect.

This might not be true for all materials. Check out this Sandcastle example local vs. master where local doesn't apply gamma correction to the texture and it looks washed out.

Local

Master

[ProjectBarks]

I think I came to a good fix. Let me know if you find any other issues.

[lilleyse]

I'm not sure that this approach will handle every case, like if the composite material's diffuse is a totally separate value that doesn't reference the inner materials, but it handles the common cases well would be fine to merge. Thanks @ProjectBarks!

[ProjectBarks]

@lilleyse I think it should now. Now we check if the component fuses multiple sub materials

[lilleyse]

The updates look good, thanks @ProjectBarks!