444 AutoCAD and Its Applications—Basics Copyright Goodheart-Willcox Co., Inc. All objects in the DWG 1 and DWG 2 fi les that have the same X, Y, and Z position display in the same gray color (color 253). Objects that differ between the two draw- ings display in the specifi ed DWG 1 and DWG 2 colors. A rectangular revision cloud, drawn on the 0-Markups layer and displayed in orange (color 40), appears around each change set. The eight change sets in Figure 15-27B identify revisions made to the fl oor plan by the second drafter. In this example, the refrigerator has been moved and a different window has been specifi ed in the kitchen, the dining and living rooms have been redesigned with vaulted ceilings, and an entry wall and broom closet have been enlarged. Revision clouds, described in Chapter 18, are cloud-shaped polyline objects used to identify changes in a drawing. Like other AutoCAD objects, they can be modi- fi ed or erased. Use the 0-Markups layer as needed. For example, assign a different color to change the color of revision clouds or use the layer to add revision marks and notes. The Compare contextual ribbon tab offers an easy approach to working with comparison fi le options. Figure 15-28 describes each item in the Compare contextual ribbon tab. Figure 15-27. Using the COMPARE command to analyze a residential floor plan before and after a design revision. A—The Compare contextual ribbon tab appears when the comparison drawing is generated. B—Change sets in the comparison drawing indicate differences between the original drawing and the revision drawing. A revision cloud appears around each change set. In this example, there are eight change sets. A B Compare contextual ribbon tab Display controls for DWG 1 and DWG 2 objects in comparison drawing Pick to add a table with comparison data Pick to cycle between change sets Object unique to DWG 2 Object unique to DWG 1 Objects in gray are the same in both drawings Revision clouds drawn around change sets