unwanted outline using raw data rendering

I am repost the question with some more clarifications. Hope anybody can help me with this. Thanks in advanced

I am render the base map using tileImageryProvider

but instead of returning an image, I returned a canvas object.

The data that represent a single tile is a 2D array of pixel value 0-255 and drawn to an ImageData

Everything work except that level 2+ shows an outline of the tile.

Is this because canvas 2D rendering problem?

Let me know if anyone know how to remedy the problem.

Thanks

I’m not sure if you figured this out yet or not, but I think this is a problem in the actual tiles you are generating. Have you dumped the canvas tiles to the screen to see how they look outside of Cesium? If you think this is a bug in Cesium, can you reproduce it in a small test case for us?

Thanks