Ever wonder about freezing a layer vs turning a layer off? Aren't they the same? Well, they are indeed similar, but there are differences. Let's take a closer look, and explore the Layers Tab a little, too.
ON/OFF: When a layer is turned on, objects are visible and selectable. When a layer is OFF, all entities are invisible, but are still regenerated with the Regen command.
While OFF layer entities are not selectable by any pick method (since they are not visible), OFF objects are selected when ALL is used as the selection method. CTRL+A (_ai_selall) adds OFF layer objects to the selection set, too.
Lastly, OFF applies to all layouts, and model space: OFF everywhere, or ON everywhere.
The icons for this are the bright light bulb (ON) and the dark light bulb (OFF).
FREEZE/THAW A thawed layer means it is visible and selectable. A Frozen layer is invisible, same as an OFF layer, but it is not regenerated with a Regen, and it is not selected with ALL or _ai_selall.
For those mathematically minded: FREEZE = OFF + LOCK.
Frozen layers are frozen everywhere, in all layouts and model space, same as off layers. THAW is the opposite of FREEZE, objects are visible, and selectable.
Icons are blue snowflake (FREEZE), and yellow sun (THAW).
VP Freeze allows users to control display of layers unique to each view port or layout. A VP Frozen layer is invisible, but only in the spaces where it is VP Frozen. It is a simple and powerful way to manage display of content unique to each view port.
The Layers tab on the Home Ribbon Panel have powerful layer editing tools, including isolating a layer or layers, freezing a layer, or turning a layer off, all by object selection, a layer list, and layer state selector. Layer tools, like LAYMCUR, LAYOFF, LAYFRZ, LAYISO are all there, too! Check it out!