Add SSRrPass (screen space refraction) (#21420)

* SSRPassCorrectReflectorDepth

* Fix? or bypass? large groundReflector edge viewing problem.

* Renaming & some clean up.

* SSRr init copy from SSR

* ok: rename SSR to SSRr & remove groundReflector

* clean up

* clean: blur

* a

* a

* pok

* debug_effect

* pok

* pok

* doing

* doing

* add gui ior

* ok

* screenshot

* bugfix: Correct transparent object z-depth occlusion.

* add vconsole

* Add specular.

* Generalize & Clean up.

* Click toggle transparent.

* Rename: specularRenderTarget.
Fix: scene.background.
MouseMove Check: Zero is sufficient.

* Correct IOR.

* Fix: Tiny gaps display error.
Rename: tSpecular.

* Clean up.

* Rename: Metalness to Refractive.
Add: Specular togglable.

* Make `defines` all uppercase.

* Add `Specular` OUTPUT.

* BugFix: Corrent `tDepthSelects`.
Add: `DepthSelects` OUTPUT.

* Rename: `normal` to `normalSelects`.

* Let `away` consider `surfDist`.

* Setting: `maxDistance` configurable.

* Use `pointToLineDistance`.

* All use `NearestFilter`.

* Add: `infiniteThick`.

* Increase `maxDistance`.

* Add setting: fillHole.

Author: gonnavis

examples/files.json

@@ -262,6 +262,7 @@
 		"webgl_postprocessing_sobel",
 		"webgl_postprocessing_ssao",
 		"webgl_postprocessing_ssr",
+		"webgl_postprocessing_ssrr",
 		"webgl_postprocessing_taa",
 		"webgl_postprocessing_unreal_bloom",
 		"webgl_postprocessing_unreal_bloom_selective"