Using custom terrain (generated by cesium-terrain-builder, using quantized mesh branch) with underwater elevations, and a rectangle with image material classified against the terrain, the image doesn’t render below around -20m.
Here’s the code for adding the rectangle. Same behaviour occurs even if it’s just a material with a solid RGB colour and no transparency.
viewer.entities.add({
rectangle: {
coordinates: Rectangle.fromDegrees(…bounds),
material: new ImageMaterialProperty({
image: filename,
color: Color.WHITE.withAlpha(transparency),
transparent: true
}),
classificationType: ClassificationType.TERRAIN
}
});
``
Using Cesium 1.64, but it was happening back in 1.58.1 and possibly before. I know you’re not the authors of ctb, but the terrain behaviours correctly as far as I can see.
Using Cesium Ion to generate terrain tiles, then adding a rectangle in the sandcastle produces the same result, albeit at a different elevation. Mouse interaction with the rectangle ceases where rendering cuts off.
Using Cesium Ion to generate map tiles for a raster, then adding this to viewer.imageryLayers with the Ion generated terrain, correctly renders the raster.