Annotative scale has been in AutoCAD since 2007 and it is still the thing that most reliably confuses people. The idea is simple. The behaviour, once you have three viewports and an xref, is not.
This is what it actually does, why your text disappears, and the handful of traps that account for nearly every complaint about it.
What annotative actually does
Normally an object has one size. A piece of text 250 mm high in the model plots 2.5 mm high through a 1:100 viewport, and 0.25 mm high through a 1:1000 one. You either accept that or you keep two copies of the text.
An annotative object stores the height you want on paper and then holds a separate scale representation for every scale you have told it about. One object, several sizes, each one the right size for the viewport it appears in.
| Ordinary object | Annotative object | |
|---|---|---|
| What you set | the model height (250 mm) | the paper height (2.5 mm) |
| Sizes stored | one | one per supported scale |
| Change the sheet scale | you recalculate and reset every object | nothing to do, if the scale is supported |
| Two scales on one sheet | two copies of the annotation, on separate layers | one object, shown correctly in both viewports |
| If the scale is not supported | still shows, at the wrong size | does not show at all |
That last row is worth repeating, because it is the single most common complaint: an annotative object that has no representation for the current scale is invisible. It has not been deleted. It simply has nothing to draw at that scale.
The rule
Set the paper height once. Give each viewport its scale. Stop calculating.
Everything in the drawing scale chart — text height, DIMSCALE, hatch scale — is a multiplication AutoCAD will do for you the moment the object is annotative. The chart is what the software is calculating, and what you still need for everything that is not annotative.
What can be annotative
| Object | Made annotative by |
|---|---|
| Text and mtext | an annotative text style |
| Dimensions | an annotative dimension style (DIMANNO reports whether the current one is) |
| Leaders and multileaders | an annotative multileader style |
| Hatch | the Annotative tick in the hatch dialog (HPANNOTATIVE sets the default) |
| Blocks | the Annotative tick in the Block Definition dialog |
| Attributes | separately from their block — both need setting |
| Tolerances | an annotative dimension style |
| A whole drawing | ANNOTATIVEDWG, so it behaves as an annotative block when inserted elsewhere |
Attributes are the one that catches people. A block can be annotative while its attributes are not, and the attributes will then scale with the geometry instead of holding their paper height.
Setting it up
- Make the style annotative — text, dimension or multileader — and set the paper height in it, not the model height. 2.5 mm, not 250.
- Set the current annotation scale before you draw. That is
CANNOSCALE, on the right of the status bar. Objects are created supporting whatever scale is current. - Draw the annotation.
- In the layout, give each viewport its scale. Annotative objects that support that scale appear at the right size.
- For any object that needs to appear at more than one scale, add the extra scales with
OBJECTSCALE.
Post 121 is the worked example, with screenshots of the same hatch and dimension coming out at 2:1, 1:1 and 1:2 with the annotation staying the same printed size: Understanding annotation scales in AutoCAD.
The traps
1. The annotation vanished
Almost always the object has no scale representation for the current annotation scale. Set the viewport to a scale the object supports, or add the scale to the object with OBJECTSCALE.
To see what is there but not supported, turn on ANNOALLVISIBLE. Autodesk’s description: it “hides or displays annotative objects that do not support the current annotation scale.” It is saved separately for model space and for each layout, so turning it on in one layout does not turn it on in the next — which is why it can look like the setting did not stick.
2. Scales you never asked for
ANNOAUTOSCALE “updates annotative objects to support the annotation scale when the annotation scale is changed.” Convenient, and also the reason an object can quietly accumulate a dozen scale representations because somebody cycled through the scale list while it was selected. Turn it off if you want to add scales deliberately.
3. Scale list bloat — and PURGE will not fix it
Xrefs and inserted blocks bring their scale lists with them. Nested xrefs compound it. Eventually the drawing opens with a warning that it “contains a large number of annotation scales”, and Open, Xref, Insert and Copy/Paste all slow down.
The PURGE command cannot remove annotation scales. That surprises most people, and it is why the usual clean-up ritual does nothing here. The options that do work:
| Approach | What it does | Cost |
|---|---|---|
| Open and resave the xref | Removes the excess scales at the source, so they stop arriving | Best fix, but you need access to the xref |
-SCALELISTEDIT → Reset | Restores the default scale list | Destroys your custom scales too — note them first |
| Scale List Cleanup Utility | Removes unused annotation scales | A separate Autodesk utility |
PURGE | Nothing. Annotation scales are not purgeable | — |
Command: -SCALELISTEDIT
Enter option [?/Add/Delete/Reset/Exit] <Add>: R
Reset scale list to defaults? [Yes/No] <No>: Y
Enter option [?/Add/Delete/Reset/Exit] <Add>: E4. The representations have drifted apart
Each scale representation can be moved independently — that is a feature, because a note that clears the geometry at 1:100 may sit on top of it at 1:50. It becomes a problem when they drift by accident. ANNORESET “resets the locations of all alternate scale representations of the selected annotative objects” back to the current one.
5. Ghost copies when you select something
Selecting an annotative object shows its other scale representations dimmed, which reads as duplicate objects. That is SELECTIONANNODISPLAY, which “controls whether alternate scale representations are temporarily displayed in a dimmed state when an annotative object is selected”. The dimming level comes from XFADECTL. Set it to 0 if it bothers you.
6. The style changed but the objects did not
ANNOUPDATE “updates existing annotative objects to match the current properties of their styles”. Reach for it after editing an annotative style and finding the objects unchanged.
System variable reference
| Variable | What it controls |
|---|---|
CANNOSCALE | The name of the current annotation scale for the current space |
CANNOSCALEVALUE | The value of the current annotation scale (read-only) |
ANNOALLVISIBLE | Hides or displays annotative objects that do not support the current annotation scale. Saved per space and per layout |
ANNOAUTOSCALE | Updates annotative objects to support the annotation scale when it changes |
SELECTIONANNODISPLAY | Whether alternate scale representations are shown dimmed when an object is selected |
ANNOTATIVEDWG | Whether the drawing behaves as an annotative block when inserted into another drawing |
DIMANNO | Reports whether the current dimension style is annotative (read-only) |
HPANNOTATIVE | Whether a new hatch pattern is annotative |
SAVEFIDELITY | Visual fidelity for annotative objects when saved for AutoCAD 2007 and earlier |
MSLTSCALE | Whether model-space linetypes are scaled by the annotation scale. Default 1 |
PSLTSCALE | Whether linetype patterns stay consistent between viewports. Default 1 |
The last two matter more than they look. Because MSLTSCALE defaults to 1, your linetypes are already being scaled by the annotation scale — which is why LTSCALE should stay at 1 and not be set to the drawing scale factor. That is covered in full on the drawing scale chart.
When not to use it
- A drawing that will only ever plot at one scale. Annotative buys you nothing and adds a concept every future editor has to understand.
- Files going to a client who does not use it. Anything opened in AutoCAD 2007 or earlier depends on
SAVEFIDELITY, and older third-party viewers handle it unevenly. - An office standard that already works. A set of scale-named layers and text styles is less elegant but entirely reliable, and mixing the two approaches in one drawing is worse than either.
- Where the annotation must differ between scales — a 1:500 plan showing fewer labels than the 1:100. Annotative controls size, not content.
Symptom, cause, fix
| Symptom | Cause | Fix |
|---|---|---|
| Text or dimension missing in one viewport | No scale representation for that viewport’s scale | OBJECTSCALE to add the scale, or change the viewport scale |
| Annotation missing everywhere in a layout | ANNOALLVISIBLE off in that layout | Turn it on — it is saved per layout |
| Objects carry scales nobody added | ANNOAUTOSCALE on while cycling the scale list | Turn it off; remove the extras with OBJECTSCALE |
| Duplicate, faded copies of every note | Alternate representations shown on selection | SELECTIONANNODISPLAY to 0 |
| Note in the right place at one scale, wrong at another | Representations moved independently | ANNORESET |
| Edited the style, objects unchanged | Objects still hold the old style properties | ANNOUPDATE |
| Drawing slow to open; warning about many scales | Scale list inherited from xrefs and inserts | Resave the xref; or -SCALELISTEDIT Reset. PURGE will not do it |
| Hidden lines plot continuous | LTSCALE set to the scale factor as well as MSLTSCALE being 1 | Set LTSCALE back to 1 |
References
- Autodesk, Commands for Annotation Scaling, for the command and system variable descriptions quoted above. help.autodesk.com
- Autodesk, ANNOALLVISIBLE (System Variable). help.autodesk.com
- Autodesk, SELECTIONANNODISPLAY (System Variable). help.autodesk.com
- Autodesk, Custom scales cause performance issues with Open, Xref, Copy/Paste, and Insert functions, for the scale list bloat and the -SCALELISTEDIT Reset procedure. autodesk.com
- Autodesk, Annotation scales cannot be deleted in AutoCAD, for why PURGE does not remove them. autodesk.com
- Autodesk, Prevent Xref Annotation scales from being copied to the host drawing in AutoCAD. autodesk.com
- Autodesk, How to manage linetype scale system variables (MSLTSCALE and PSLTSCALE) in AutoCAD. autodesk.com
- Understanding annotation scales in AutoCAD — the worked example, by Jaiprakash Pandey, with the sample drawing.
- Drawing scale chart: metric and imperial — the multiplications annotative does for you.
- Text heights in drawings — which paper height to set in the style.