====== 3. Commands ======

===== 3.1. AutoCAD 2020 ===== 

==== 3.1.1 New and changed commands ====

|**BLOCKSPALETTE** | Opens the palette of blocks. |
|**BLOCKSPALETTECLOSE** | Closes the palette of blocks. |
|**CLASSICINSERT** | Opens the classic Insert dialog box. |
|**INSERT** |Starts the BLOCKSPALETTE command except in scripts that open the older INSERT command for script compatibility. |
|**-INSERT** |Starts the command line version of the classic INSERT command. |
|**Cleanup** | Opens the newly designed Cleanup dialog box. |
|** COMPARISON** | Closes the comparison toolbar and ends the comparison. |
|**COMPAREEXPORT** | Exports the comparison results to a new drawing called a snapshot drawing and opens the drawing. |
|**COMPAREIMPORT** |Imports objects from the comparison file into the current drawing. Only the selected objects that are present in the comparison file and not in the current file are imported. |
|**MEASUREGEOM** | Adds the Quick option for real-time measurements. |
|**AMDIMARRANGE** | Now supports the arrangement of multiple horizontal and vertical dimensions. |
|**TEXTLAYER** | Defines a default layer for new text and multiline text objects in the current drawing. |


==== 3.1.2 New system variables ====

|**BLOCKMRULIST** | Controls the number of blocks displayed on the Recent tab of the block palette. |
|**BLOCKNAVIGATE** | Controls the file and blocks displayed on the Other Drawing tab of the Block Palette. Effective the next time the program is started. |
|**BLOCKREDEFINEMODE** | Controls whether the Block - Redefine Block task dialog box appears when a block from the block palette with the same name as a block is inserted within the current drawing. |
|**BLOCKSTATE** |Reports whether the block palette is open or closed. |


===== 3.2 AutoCAD 2019 =====

==== 3.2.1 New and modified commands ====
|**Compare** | Compare the differences between two revisions of the same drawing or different drawings and highlight them. |
|**-compare** | The command window is used to compare and highlight the differences between two revisions of the same drawing or different drawings. |
|**COMPARISONINFO** |Pastes or copies the property information of the two compared drawing files. |
|**sharedviews** |Opens the Shared Views palette. |
|**sharedviewsclose** |Closes the Shared Views palette. |


==== 3.2.2 New System Variables =====
|**COMPARECOLOR1** | Defines the color of the objects that are only present in the first drawing in the file of the comparison result drawing. |
|**COMPARECOLOR2** | Defines the color of objects that are only present in the second drawing in the file of the comparison result drawing. |
|**COMPARECOLORCOMMON** | Determines the color of the objects that are identical in the two compared drawings. |
|**COMPAREFRONT** | Defines the default display order of overlapping objects in the comparison results drawing. |
|**COMPAREHATCH** | Determines whether hatch objects are included in the drawing comparison. |
|**COMPAREPROPS** | Determines whether a change in a non-geometric (display) property is recognized as a change between two drawing revisions. |
|**COMPARERCMARGIN** |Specifies the offset distance of the boundary frame of a revision cloud that marks the object differences in a comparison result drawing. |
|**COMPARERCSHAPE** | Determines whether nearby individual changes are merged as a single large rectangle or multiple small rectangles in the comparison results drawing. |
|**COMPARESHOW1** | Displays the objects that only exist in the first drawing. |
|**COMPARESHOW2** | Displays the objects that only exist in the second drawing. |
|**COMPARESHOWCOMMON** | Displays the objects that match in both drawings being compared. |
|**COMPARESHOWRC** |Displays a revision cloud over the difference in the comparison result drawing. |
|**COMPARETEXT**| Determines whether text objects are included in the drawing comparison. |
|**COMPARETOLERANCE** | Specifies the tolerance used when comparing two drawing files. Objects are considered identical if they are less than or equal to a certain decimal value. |
|**FILLETPOLYARC** | Determines the rounding behavior of polylines with arcs, either current or obsolete. Only affects the Polyline option of the ROUND command. |
|**MVIEWPREVIEW** | Controls the preview behavior when inserting a named or new layout viewport. |
|**SECUREREMOTEACCESS** | Determines whether files can be accessed from the Internet or from remote servers. |
|**SHAREVIEWPROPERTIES** | Determines whether drawing properties are considered for shared views. |
|**SHAREVIEWTYPE** | Determines whether a shared view is created from the current view, model space, layout, or the entire drawing. |
|**STUDENTDRAWING** | Indicates whether the current drawing was saved with the student version of an Autodesk product. |


===== 3.3. AutoCAD 2018 =====

==== 3.3.1 New and changed commands ====

|**NEUANS** |Saves a new named view from the display in the current viewport or by defining a rectangular window. |


==== 3.3.2 New System Variables =====

|**LAYEROVERRIDEHIGHLIGHT** |Activates or deactivates the visibility of the background color marker for layers with overrides. |
|**THUMBSIZE2D** | Controls whether the thumbnails of drawings with 2D visual wireframe styles are set to a screen resolution of 256 x 256 pixels. |
|**VISRETAINMODE** | Controls the behavior of the VISRETAIN system variable, which is set to 1. |
|**XREFLAYER** | Specifies a default layer for a new XRef. |
|**PDFSHX** | Converts the SHX geometry imported from PDF files into individual multiline text objects. |
|**MILLISECS** | Stores the number of milliseconds elapsed since the system was started. |
|**PDFSHXBESTFONT** | When converting imported PDF geometry to text, checks whether the PDFSHXTEXT command selects the font with the best match or the first font that exceeds the recognition threshold. |
|**REFPATHTYPE** |Controls whether the referenced files use complete, relative, or no paths when first mapped to the file of a parent drawing. |
|**SELECTIONOFFSCREEN** | Controls the selection of objects outside the screen. |


===== 3.4. AutoCAD 2017 ======

==== 3.4.1 New and changed commands =====

|**AMLGISO** | Hides or locks all layergroups except those of the selected objects. |
|**AMLGUNISO** | Recovers all layergroups hidden or locked with the AMLGISO command. |
|**AMMOTOR2D** | Inserts a motor from a standard parts library. |
|**AMRECTBWH** | Creates a rectangle by selecting the center of the base as the starting point and specifying the full base and height. |
|**AMRECTBWH2** | Creates a rectangle using the center of the base as the starting point and specifying half the base and full height. |
|**AMRECTCW2H** | Creates a rectangle using the center of the rectangle as the starting point and specifying half the base and full height. |
|**AMRECTCW2H2** | Creates a rectangle using the center of the rectangle as the starting point and specifying half the base and half the height. |
|**AMRECTCWH** | Creates a rectangle using the center of the rectangle as the starting point and specifying the whole base and height. |
|**AMRECTCWH2** | Creates a rectangle using the center of the rectangle as the starting point and specifying the full base and half the height. |
|**ARMRECTLWH** | Creates a rectangle using the center of the height as the starting point and specifying the full base and height. |
|**AMRECTLWH2** | Creates a rectangle by selecting the center of the height as the starting point and specifying the full base and half the height. |
|**AMRECTQBT** | Creates a square using the base center as the starting point and specifying the full base. |
|**AMRECTQBY** |Creates a square using the center of the base as the starting point and specifying half of the base. |
|**AMRECTQCR** |Creates a square using the center of the square as the starting point and specifying half the base. |
|**AMRECTQCW** |Creates a square using the center of the square as the starting point and specifying the length of the base. |
|**AMRECTQLR** |Creates a square using the center of the height and specifying the full base. |
|**AMRECTQLY** |Creates a square using the center of the height as the starting point and specifying half the base. |
|**AMRECTQXY** |Creates a square using a corner of the base as the starting point and specifying the full base. |
|**AMRECTXWH** |Creates a rectangle using a corner of the rectangle as the starting point and specifying the full base and height. |


==== 3.4.2 New system variables =====

|**AMLGCOLORMODE** | Makes the layergroup color available for editing. |
|**AMLGLTMODE** | Makes the line type of the layer group available for editing. |
|**AMLGLWMODE** | Makes the Line Thickness property of the layergroup available for editing. |
|**AMNOTETAB** | Specifies whether the Annotation Icon dialog box or the context-sensitive ribbon tab of the Ribbon Command Line Comment is displayed when editing command line comments. |