Automatic 3D Billboard Imposters
ABI or Automatic Billboard Imposters is an asset for Unity3D which allows the batched drawing of large amounts of complex geometry.
This is achieved by replacing distant objects with photographs, which are generated for each object at three orthogonal views (front, right, and top). This means that there are significantly fewer triangles and texture memory used in the final scene.
Stippling shaders are also employed to smoothly transition between model and photograph, when the projected model size is less than some threshold. These shaders blend with a subtle low-frequency Gaussian bubbling effect.
Hardware batching ensures that the number of draw calls remains low, which is especially useful when thousands of objects are instanced.
The package can be downloaded here.