Model / terrain masking should work for large models

[markschlosseratbentley]

Clip masks allow the geometry of a model to clip out portions of reality models, terrain, and background maps. They do so by rendering the geometry to a texture which is then sampled in the fragment shader. Because textures have a maximum resolution, the larger the area being masked, the less accurate the mask is. This can produce visibly jagged boundaries.

Masking is useful for road and rail projects, which often span many kilometers, making them vulnerable to this problem. Come up with a solution to minimize the visual artifacts - for example, by tiling the mask into multiple textures.

The same texture resolution issue affects model map layers.