fix(troika-three-text): survive WebGL context loss during SDF glyph generation

packages/troika-three-text/src/SDFGenerator.js

@@ -116,7 +116,22 @@ function generateSDF_JS_Worker(width, height, path, viewBox, distance, exponent,
       for (let i = 0; i < textureData.length; i++) {
         imageData[i * 4 + channel] = textureData[i]
       }
-      mainThreadGenerator.webglUtils.renderImageData(canvas, imageData, x, y, width, height, 1 << (3 - channel))
+      // The atlas context may have been lost while the worker was generating (before the async
+      // webglcontextlost event has flipped atlas.contextLost), in which case this GL write would
+      // throw from deep inside webgl-sdf-generator as an unhandled rejection, one per in-flight
+      // glyph, and strand the typeset callback. Dropping the write is safe: the TextBuilder's
+      // webglcontextrestored handler regenerates every known glyph into the restored atlas. A null
+      // probe means context creation was refused under the same GPU pressure - equally benign to
+      // drop, and no restore event will ever fire for a context that never existed. The probe
+      // passes the generator's context attributes so a probe that succeeds can't stick a
+      // wrong-attribute context onto the atlas. Rethrow only when a healthy context proves the
+      // error was unrelated.
+      try {
+        mainThreadGenerator.webglUtils.renderImageData(canvas, imageData, x, y, width, height, 1 << (3 - channel))
+      } catch (err) {
+        const gl = typeof canvas.getContext === 'function' ? canvas.getContext('webgl', { premultipliedAlpha: false, preserveDrawingBuffer: true, antialias: false, depth: false }) : null
+        if (gl && !gl.isContextLost()) throw err
+      }
       timing += now() - start
 
       // clean up workers after a while

packages/troika-three-text/src/TextBuilder.js

@@ -317,7 +317,16 @@ function getTextRenderInfo(args, callback) {
     if (neededHeight > currentHeight) {
       // Since resizing the canvas clears its render buffer, it needs special handling to copy the old contents over
       console.info(`Increasing SDF texture size ${currentHeight}->${neededHeight}`)
-      resizeWebGLCanvasWithoutClearing(sdfCanvas, textureWidth, neededHeight)
+      // If the context was lost, the canvas dimensions are still applied before the GL copy-over
+      // throws; drop the copy in that case - the webglcontextrestored handler regenerates every
+      // glyph into the resized atlas. The dispose below must still run either way so the texture
+      // reallocates at the new canvas size.
+      try {
+        resizeWebGLCanvasWithoutClearing(sdfCanvas, textureWidth, neededHeight)
+      } catch (err) {
+        const gl = sdfCanvas.getContext('webgl', { premultipliedAlpha: false, preserveDrawingBuffer: true, antialias: false, depth: false })
+        if (gl && !gl.isContextLost()) throw err
+      }
       // As of Three r136 textures cannot be resized once they're allocated on the GPU, we must dispose to reallocate it
       sdfTexture.dispose()
     }