Introduce Scene.environmentIntensity

[WestLangley]

As suggested in #24665 (comment).

Currently, material.envMapIntensity attenuates both scene.environment and material.envMap.

With this change, material.envMapIntensity attenuates only material.envMap.

A new property scene.environmentIntensity is introduced that attenuates only scene.environment.

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

Filesize dev	Filesize PR	Diff
669.7 kB (166.2 kB)	670 kB (166.2 kB)	+344 B

🌳 Bundle size after tree-shaking

Minimal build including a renderer, camera, empty scene, and dependencies.

Filesize dev	Filesize PR	Diff
449.9 kB (108.8 kB)	450.2 kB (108.8 kB)	+263 B