Use image-compare widget

[ickk]

Use the image-compare widget where it's obvious to do so.

This depends on #689 and cherry-picks #680

The Tonemapping section needs new images that are more suitable for this
and in general it would be good to standardise the placement of and size of titles in the images.
Thanks to @nicopap we can use markup to add titles to the images

[ickk]

It won't work unless you have #689 as well

[nicopap]

Yeah. I cherry picked the commit, now it works. Sorry.

[nicopap]

Hmm. A shame we don't have the slider for RCAS off/on and msaa/taa. Those would also benefit from it.

[ickk]

Hmm. A shame we don't have the slider for RCAS off/on and msaa/taa. Those would also benefit from it.

Hopefully we do a pass on the images before release to standardize them (good to have text/titles in the images themselves I think), and that would be a good opportunity to add RCAS off/on (I need separate images that are full-width).

For msaa/taa I'm not sure whether it's appropriate to compare them. I think no-aa/msaa & no-aa/taa could make more sense?

[nicopap]

The section titled "Temporal Anti-Aliasing" has an image that is a side-by-side comparison of TAA and MSAA. It would just be an improvement to replace that specific image with a slider comparison.

Whether it's a good comparison or not is orthogonal. But a good reason to compare MSAA and TAA would be a way to point out the various artifacts and improvements each algo have (typically MSAA is still bad with specular highlights, while TAA fixes them).

[cart]

I'll re-render some of the images and tweak the CSS a bit