Speed Tree Unity
Screenshot of the bark material.It's the only one causing flickering stretched UVs and black spots, the other materials are fine after following the steps detailed here:This is using the conifer example tree in an empty new project using Unity 2018.3.6f1 in HDRP.The lighting setup is a single directional light.Switching the material to 'Unlit' fixes the UV stretching and black spots.Made sure to disable SRGB on the mask map and import the normal map as a normal map.Here's a screenshot of the materials remaped.
Speedtree Download
SpeedTree Assets (.spm files saved by Unity version of SpeedTree Modeler) are recognized and imported by Unity just like other Assets. Ensure Textures are reachable in the Project folder, and Materials for each are generated automatically. There are import settings when you select.spm Assets for you to tweak the generated GameObject and attached Materials. Materials are not generated again on reimporting, unless you hit the Generate Materials, or Apply & Generate Materials button. Therefore any customisations to the Materials can be preserved.The SpeedTree importer in the end generates a Prefab with configured. The Prefab can both be instantiated in a Scene as a common Prefab instance, or be selected as a tree prototype on the terrain and be “painted” across it.
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Additionally, terrain accepts any GameObject with an LODGroup component as a tree prototype, and put no limitation on the mesh size or number of Materials being used (in contrast to the trees). But, be aware that SpeedTree trees usually use 3–4 different Materials, which results in a number of draw-calls being issued every frame, so you should try to avoid heavy use of LOD trees on platforms that are sensitive to draw-call numbers.