When an object, instance, group or a set of objects are selected in the Scene Tree, the Attributes Panel shows the list of parameters that can be changed for that selection. The panel is divided into several sections which can be expanded/ collapsed by clicking on the section title.
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You can drag and drop a material from the material list onto a triangle group to assign that material to just that triangle group. It is also possible to select a triangle group in the list, and drag and drop a material directly in the viewport. To remove a triangle group, select it and press the Delete key on your keyboard.
Additionally, if you right-click on a triangle group a menu will pop up:
Merge: Merge Creates a new triangle group from the triangle selection or merges two selected groups. The material of the first selected group will also be used for the new newly merged group of triangles.
Rename: Rename Renames a group.
Remove: Remove Removes the triangle groups but not the triangles themselves. Same as the Delete key.
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Maxwell Render allows you to apply a Modifier extension to alter the geometry of the selected object itself in render time. For an in-depth description of the Geometry modifiers extensions, see the Extensions chapter.
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The Triangle Groups section on the Object Attributes panel
The Modifiers panel allows you to add the modifiers to be applied to the selected object, as many as you want, that will be applied in descending order (the one at the top is the first to be applied to the geometry).
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