[Bug] WebGL2 renderer black screen: texStorage2D(gl.RGB) uses an unsized internal format (INVALID_ENUM)

[Endymi0n74]

Summary

The WebGL2 renderer (video.player.type = webgl2) renders a black screen because the immutable texture storage is never allocated: gl.texStorage2D() is called with an unsized internal format.

Location: src/modules/player/webgl2/webgl2-player.ts → allocateStorage():

gl.texStorage2D(gl.TEXTURE_2D, 1, gl.RGB, width, height);

gl.RGB (0x1907) is not a sized internal format, and per the WebGL2 spec texStorage2D requires a sized internal format (e.g. R8, RG8, RGB8, RGBA8…). The call fails with INVALID_ENUM, the storage is never defined, and every per-frame texSubImage2D(..., this.$video) upload then fails too:

GL_INVALID_ENUM: glTexStorage2D: The <internalformat> is not a sized or compressed texture format or it is unsupported in the current context.
GL_INVALID_OPERATION: glCopySubTextureCHROMIUM: The destination level of the destination texture must be defined.

Result: black canvas (no video frames), no GL error surfaced to JS.

Reproduction

1. Set video.player.type to webgl2 in Better xCloud settings.
2. Start any stream → black video output.

Confirmed outside xCloud too, in a plain WebGL2 context with a real <video> element (Edge, ANGLE/D3D11), by rendering the texture to an FBO and reading pixels back:

internalformat	texStorage2D	framebuffer	readPixels
gl.RGB	INVALID_ENUM (0x500)	INCOMPLETE	100 % black (avg 0, 0 % non-zero)
gl.RGB8	OK	COMPLETE	real video content (avg ~130, 98.5 % non-zero)

Fix

One line in allocateStorage():

gl.texStorage2D(gl.TEXTURE_2D, 1, gl.RGB8, width, height);

texSubImage2D(gl.TEXTURE_2D, 0, 0, 0, gl.RGB, gl.UNSIGNED_BYTE, this.$video) in updateFrame() is fine as-is — unsized formats are valid as upload formats for texSubImage2D.

Impact

Only sessions that use the WebGL2 renderer (not the default player type). The WebGPU renderer has the same pattern (paramsBuffer/uniform path) but is unaffected. This is fixed and shipped in my fork release better-xcloud-perf v1.4.0 (patch 18); happy to send the TS change if preferred.