Override Surfaces With Surface Painter

Use the Surface Painter palette, described below.
Note: Before using the Surface Painter feature, make sure you are not working in “legacy” intersection mode. (Uncheck this option at Options > Project Preferences > Legacy.)
Open the Surface Painter palette (Window > Palettes > Surface Painter).
Alternatively, click the Pick up Surface icon in Surface Painter, then click on any element surface in the 3D window to select it in Surface Painter.
Note: The default Paint Mode means that you will exit Paint Mode automatically after a single painting interaction. If you wish to paint multiple items without exiting Paint Mode, use the Infinite Paint mode: See “Infinite” Paint Mode, below.
Note: While you are in Paint mode, click Alt at any time to enable the Pick up Surface function. This way, you can paint using a picked-up surface.
The Info Tag shows which surface will override which. As needed, click Tab to cycle among the faces, or to select all faces/edges.
Note: If the clicked element has faces using several different surfaces, you can choose “All Similar Faces”: that is, you will override not just the clicked face, but all element faces which use the same surface.
Note: If want to keep painting without exiting automatically, you should use the “infinite” Paint Mode, described below.
If you override edges, all the edges are overridden uniformly, including any custom edges of a roof or slab.
If you change any surface in a GDL object, all parts of the GDL object which use that surface will be changed uniformly. In other words, you cannot paint only a particular face of a GDL object; only the “All Similar Faces” option applies.
press Esc
press Cancel from the context menu
click the Paint mode toggle in Surface Painter
Alternatively, select all project elements that use a particular surface: right-click the surface from the content list and use the Select all elements using... command.
Note: To find a particular surface in the Surface Painter content list, you can use the Pick Up Surface function on an element which uses that surface.
Note: GDL-object type elements do not use Building Materials. Consequently, any overrides applied to those objects are not affected by the Remove All Surface Overrides command. To change their surfaces, use Object Settings.