Textures are applied to 3D polygons and walls based on the direction the object was drawn. For 3D polygons, the texture is applied parallel to the first segment.
The starting point and direction the wall is drawn affects how a texture is applied. Textures are applied to a wall’s left side, right side, and center. The center of a wall is always the same, but the left and right sides change based on drawing direction. When drawing a wall in a clockwise direction, the left side is the exterior side; however, drawing the wall in a counterclockwise direction makes the left side the interior side.
If the texture(s) is incorrectly applied to a wall, with the wall selected, click Reverse Sides on the Shape tab of the Object Info palette. This flips the direction of the wall, switching the texture(s) to the opposite side(s).