Google Photorealistic 3D Tiles render corrupted (vertical stripes) on Chrome 151 / Samsung Xclipse 940 — Mapbox GL JS renders clean on same device

[avsedatsel]

What happened?

Summary

CesiumJS renders Google Photorealistic 3D Tiles with severe corruption on a specific
browser+GPU combination: sharp, full-height vertical coloured stripes covering part of
the canvas, with a clean diagonal boundary against the correctly rendered region. It is
present in the first frame and never clears.

Crucially: Mapbox GL JS renders perfectly on the exact same device, same browser, same
page (satellite raster + raster-dem terrain + 3D pitch + animated camera). So WebGL on
this device is not broken in general — something specific to CesiumJS's rendering is
incompatible here.

Environment

• Device: Samsung Galaxy S25 FE (SM-S731B), Android 16 (BP4A.251205.006)
• GPU/driver: ANGLE ((Samsung Xclipse 940) on Vulkan 1.3.279), OpenGL ES 3.2,
  DRIVER_VERSION 24.1.307 — the device's own GLES driver is itself an ANGLE-on-Vulkan layer
• Browser: Chrome 151.0.7922.83 (Android) — BROKEN
• CesiumJS: 1.122 (also reproduced on 1.144)
• Data: Cesium.createGooglePhotorealistic3DTileset()

Control experiments

1. Microsoft Edge 149 (Chromium) on the SAME device renders CesiumJS CLEAN.
   chrome://gpu vs edge://gpu difference:
   • Chrome: GL implementation parts = (gl=egl-angle, angle=opengles),
     Display type = ANGLE_OPENGLES, Passthrough Command Decoder = true
   • Edge: GL implementation parts = (gl=egl-gles2, angle=none),
     Display type = DEFAULT, Passthrough Command Decoder = false
     i.e. Chrome stacks its own ANGLE on top of the device's ANGLE-on-Vulkan driver.
2. Mapbox GL JS on the same device/browser/page: CLEAN.

Configurations tested — all still corrupted (19 total)

• Bare Viewer with NO options at all (default globe, AA, MSAA, SSE=16, resolutionScale)
• contextOptions.requestWebgl1 = true (WebGL 1 instead of WebGL 2)
• scene.logarithmicDepthBuffer = false
• tileset.skipLevelOfDetail = false
• scene.postProcessStages.fxaa.enabled = false AND postProcessStages.removeAll()
• contextOptions.webgl: antialias false, alpha false, stencil false,
  powerPreference 'high-performance', preserveDrawingBuffer true and false
• scene3DOnly true, shadows false, terrainShadows DISABLED, scene.fog.enabled false
• msaaSamples 0, 1, 4
• maximumScreenSpaceError 4 / 8 / 16, dynamicScreenSpaceError on/off
• resolutionScale / useBrowserRecommendedResolution: drawing buffer from 245x378 to
  1561x2409 — canvas size always equals drawingBuffer size, never clamped
• globe enabled and disabled
• CesiumJS 1.122 and 1.144
• Copying scene.canvas into a 2D canvas inside scene.postRender and displaying the copy:
  the copy is corrupted too, so the corruption is inside the WebGL drawing buffer,
  not in page compositing
• chrome://flags: #enable-vulkan Disabled, #vulkan-from-angle Disabled,
  #use-angle = OpenGL ES (verified applied via chrome://gpu command line) — still corrupted

Ask

What does CesiumJS do in its render pipeline that Mapbox GL JS does not, which could
break under a stacked ANGLE configuration? Is there any Scene/Viewer/Cesium3DTileset
option that avoids it? I am happy to run any instrumented build or test page on this
device — I have it in hand and can reproduce reliably.

Impact

This is a production app for real-estate professionals in Türkiye. Samsung Exynos
devices (Xclipse GPUs) are common here, so this affects a meaningful share of users. We
have had to detect the corruption at runtime and route affected users to a different
renderer.

Reproduction steps

...

Sandcastle example

No response

Environment

Browser:
CesiumJS Version:
Operating System:

AI acknowledgment

• I used AI to generate this issue report.
• (If the above is checked) I have reviewed the AI-generated content before submitting.