在 SceneKit 中使用 Metal 渲染地平线轮廓

我正在做一个简单的副项目，其中一小部分是渲染地形。我正在使用高度图信息渲染地形。但这是我的问题：

I would like to render just a silhouette/outline of the terrain/horizon. Here is screenshot from my app rendering height map: And here is screenshot similar to desired result from peakfinder.org:

I would like to draw just lines representing silhouette of terrain with the rest transparent or solid colour. How can I solve it? Calculate local maximum somehow?

我创建了示例项目here https://github.com/martinpilch/terrain-horizon-example，如果你想帮助我。

Thanks!