We created first a black/white mask based on the Satteliteview Image and replaced it with the Distribution Map. The Trees were placed on the Digital Terrain matching with the image, but not coordinate right.
Then we tried you methode. This works not, because the black/white map in the distribution map slot, is not matching with the satteliteview image. Maybe a UV Problem or UV Projection Problem. The sattlelite view is simple placed planar mapping.
Yes, that's the problem. Forest can use the mask a plain bitmap (replacing it with the Distribution map), or as a texture map. You can see there is two slots in the Distribution rollout for that (Bitmap/Map).
The alignment of the bitmap is done using the Offset X/Y values (or alternatively using the "Fit to Scene" buttons), but this method would not be enough precise for this work. It's better to use the mask assigning it in the "Map" slot (you need to create a texture map for this). In this case, the alignment is done using the UV coordinates of the Surface (assigned in the "Surface rollout).
- Create a "Bitmap" texture map, assign the mask to it and apply it to the Distribution->Map slot.
- Assign the terrain to Forest->Surfaces.
- To align visually the mask in the terrain, i suggest to use a material with the mask in the Diffuse slot and apply it to the Surface (this has no relation with Forest, but help you to adjust the UV coordinates).
- Be sure the Distribution Map->Map Channel matches with the mapping channel of the Surface.
You can use the above sample scene as reference. It uses exactly this method.
Now we created a Vector Mask based on the Black and White Map. Imported it into max and now have another problem. If we pick our Terrain, place Forest on it, and pick the Vector mask as Spline Area, the Trees are not placed right. They are still placed over the whole terrain.
Probably the Areas->Surface Areas checkbox is "On". In this case, the full surface is used as a scattering area. You must turn off it when using other "Include" areas (Splines or Paint).
Next Try was to use the Vector Mask as our Forest "Surface". This works fine, the Trees are placed right matching the image map. But of course a Terrain has Hills and Valleys - Ups and Downs - the trees are not placed right
Because the terrain must be assigned in the "Surfaces" rollout (taking care of turning off the checkbox described above).
So now we glue the Vector Mask on the Terrain. A Really complex Vector mask is now glued on the surface. Hopefully this works.
That doesn't work. The elevation of the spline's vertex is not used in Forest.
And hey"happy eastern"
Thanks ! Same for you.