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Drop Objects to a Terrain

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Yes, you can use the Surface Scatter tool in the specialties palette. It gives a lot of control regarding amount of copies, direction, justification, etc.

It's handy if you have for example a tree or plant cutout that you want scattered on a surface and works great with an undulating nurbs surface.

Be careful with high poly objects so you don't overload your file.

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There used to be a script back in the day for FormZ V6.x. called gravity which would do exactly that for you.

I don't think it works with V9 😢


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2 hours ago, Justin Montoya said:

If you enable Snap to Face, that should do what you want, no?


Thanks Justin. I think that Snap setting would work if the surface was level. Mine is inclined.

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Also look into the Paint Objects Tool Plug-in from LAB (Thanks Ben!)



Basic Workflow
Pre-pick or post-pick any number of source objects, groups, or Components. Hold down the shift key to select multiple objects. 
To paint, first release the shift key if depressed, then click and drag over the target surface(s). Once the source objects have been loaded into the tool, you can paint multiple strokes (click-drag movements) without re-selecting them.

Reload with New Source Objects
Paint Objects tool active, it is possible to ‘reload’ with new source objects without clearing the collision detection buffer. From the formZ main menu, choose Edit > Deselect, or hit your equivalent key shortcut. Then, select a new object and begin painting again. Note that it is necessary to hold down the shift key to select multiple objects.

Speeding things up
When placing objects with many thousands of polygons, Paint Objects may respond more slowly. 
For a more responsive experience, try the following:

Enable ‘Bounding Box Preview’ mode.

Consider joining groups composed of many objects into fewer objects (use formZ’s Join tool).

Consider converting the source geometry to a Component. Then, in Display Options, change Component Display to Bounding Box.


Most tool options are self-explanatory, but a few details follow:

Bounding Box Preview
When enabled, bounding boxes will be placed when painting. When the mouse button is released at the end of a stroke, the bounding boxes will be replaced with the final geometry. With complex objects, this speeds up painting dramatically. 

Place Mode

Single creates a single instance. This is like formZ’s existing copy mode, but enhanced, since you can still use the randomization and collision detection features that the plugin provides.

Draw issues a linear stream of objects along the cursor position. Click-drag with the mouse to paint, release the mouse button to stop. A low density will create a line of objects with random gaps.

Paint places objects in a randomly within a circular brush field.


None will distribute placements evenly throughout the brush field.

Linear will concentrate placements near the center of the brush.

Cubic will result in even greater concentration at the center, and few placements near the edge.

Placement Intersections

Allow. Placements are allowed to freely intersect.

Avoid: Good uses world-aligned bounding boxes to reject intersections.

Avoid: Better uses local object/group axis-aligned bounding boxes. Allows for significantly tighter packing than the Good option, with similar performance. This is the default; it works perfectly for most applications. Source objects’ axes should be aligned to the minimum of the object for best results.

Avoid: Best computes actual intersections of objects. May be slow.

Source Axes

Use Object/Group Axes. Use formZ’s Edit Axes tool to modify the origin and axis of the source object/group/Component. This allows one to, for instance, set the axis so placements will be slightly embedded when painted on a destination surface.

Bottom, Center of Selection. The source origin will be computed at the average point for x and y, and at the minimum for z. Axes will be world-aligned. Useful for many entourage cases, where this is often the desired origin.

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