Revision clouds highlight areas of a drawing that have been changed or require attention. They consist of arcs forming a cloud-like outline — instantly recognizable to anyone reviewing a drawing.
Creating Revision Clouds
Type REVCLOUD at the command line or find it on the Home > Draw panel.
Rectangular
Pick two opposite corners. AutoCAD draws a rectangular revision cloud.
REVCLOUD → Rectangular
Polygonal
Pick points to define a custom polygon shape around the revised area.
REVCLOUD → Polygonal
Freehand
Draw by dragging the cursor — creates an organic, freehand cloud shape.
REVCLOUD → Freehand
Object
Convert an existing closed shape (circle, polyline, ellipse, spline) into a revision cloud.
REVCLOUD → Object
Arc Length Settings
The cloud is made of arcs. Shorter arcs = more bumps, tighter cloud. Longer arcs = fewer bumps, smoother cloud. Set arc length during the REVCLOUD command:
| Setting | How to Set | Notes |
|---|---|---|
| Minimum arc length | REVCLOUD → Arc length → enter value | Minimum bump size. Usually set equal to or slightly less than maximum. |
| Maximum arc length | Entered immediately after minimum | Maximum bump size. Must be ≤3x the minimum per the REVCLOUD rule. |
| Default arc length | Saved in drawing; changes per drawing | AutoCAD remembers the last-used arc length per drawing file. |
📌 Recommended arc length: For a 1:1 drawing, try 3–6 inches minimum / maximum. For a drawing at 1:50 scale (and if you want the cloud to print at 6mm bumps), set arc length to 300mm.
Styles
| Style | Description | When to Use |
|---|---|---|
| Normal | Standard uniform arcs | Most drawings; clean, professional look |
| Calligraphy | Variable-width strokes that vary with direction (simulates pen pressure) | When a hand-drawn or artistic look is needed |
Change style with: REVCLOUD → Style option. The system variable REVCLOUDGRAPHIS stores the style (1 = Normal, 2 = Calligraphy).
System Variables
| Variable | Description | Values |
|---|---|---|
REVCLOUDARCVARIANCE | Amount of randomness/variance in arc sizes (introduced in AutoCAD 2021) | 0 = uniform; 1 = maximum variance |
REVCLOUDGRAPHIS | Graphical style of revision cloud arcs | 1 = Normal; 2 = Calligraphy |
REVCLOUDMAXARCLEN | Maximum arc length stored for REVCLOUD command | Drawing units (positive value) |
REVCLOUDMINARCLEN | Minimum arc length stored for REVCLOUD command | Drawing units (positive value) |
Workflow: How to Use Revision Clouds Professionally
Here's the standard workflow for revision markups on drawings:
| Step | Action | Details |
|---|---|---|
| 1 | Create a "Revision" layer | Name: REV-CLOUD. Color: Red (1) or Magenta (6). Lineweight: 0.25mm. |
| 2 | Set layer as current | All revision clouds drawn on this dedicated layer. |
| 3 | Draw revision cloud | Use REVCLOUD → Rectangular or Polygonal to surround the changed area. |
| 4 | Add revision triangle/tag | Add a revision identifier (letter or number) near the cloud, typically in a small delta/triangle symbol. |
| 5 | Update revision table in title block | Record revision letter, date, description, and approver in the title block revision table. |
| 6 | Issue drawing | Publish/plot. Revision clouds remain on the drawing as a permanent record. |
📌 Best practice: Never delete old revision clouds. Keep them on the drawing as a historical record. Use layer control to hide/show revisions as needed.
📖 Converting existing shapes: You can convert any closed polyline, circle, ellipse, or spline to a revision cloud using
REVCLOUD → Object. This is handy if you've already sketched the area with a circle or polyline.Editing Existing Revision Clouds
| Task | How To |
|---|---|
| Move | Select cloud → grip edit (center grip) or MOVE command |
| Resize | Select cloud → use vertex grips to reshape. Or delete and redraw. |
| Change arc length | Cannot change arc length of existing cloud. Delete and redraw with new arc length setting. |
| Change style | Cannot change style after creation. Delete and redraw with desired style. |
| Convert back to polyline | EXPLODE the revision cloud to convert it to a regular polyline of arcs. |