Modifying

Most of the time in CAD is spent changing what is already there. This chapter covers how to choose objects, then the tools that move, copy and reshape them.

Selecting objects

You can select first and then start a command, or start a command and select when it asks Select objects:. Both work the same.

To select	Do this
One object	Click it. Each click adds to the selection.
Everything inside an area	Click an empty spot, then click a second corner to the right. Only objects completely inside the box are selected (a window).
Everything the area touches	Click an empty spot, then click a second corner to the left. Objects inside the box or crossing its edge are selected (a crossing).
Inside a freehand shape	Press the mouse button on an empty spot and drag around the objects. This draws a lasso: dragged to the right it selects like a window, to the left like a crossing. Press Space while dragging to switch between window, crossing and fence.
Everything	Ctrl+A with no command running.
Less	Shift+click a selected object to remove it.
Nothing	Esc.

As the cursor passes over an object, it is highlighted, so you can see what a click will pick. If you prefer to drag boxes instead of clicking two corners, set PICKDRAG to 1. In version 0.8.0 it goes back to 2 the next time Musa CAD starts.

When a command asks Select objects:, keep selecting, then press Enter or right-click to finish. You can also type a selection keyword there, such as ALL, L for the last object drawn, P for the previous selection, or F for a fence. SELECT lists them all.

To select by kind and property, such as every circle on one layer, use these:

Command	Type	What it does
SELECT	SELECT	Select objects with AutoCAD's keywords (Window, Crossing, Fence, WPolygon, ALL, Last, Previous ...); the set stays for the next command.
QSELECT	QSELECT	Select by object type and property (the Quick Select dialog).
SELECTSIMILAR	SELECTSIMILAR	Select every object of the same kind and properties as the selected ones (SELECTSIMILARMODE).
FILTER	FI	Select by several type and property conditions at once.

Grips

Selected objects show small squares called grips at their key points: the ends and middle of a line, the centre and quadrants of a circle, each vertex of a polyline.

Click a grip and move the cursor to stretch the object from that point. Click again, or type a point, to place it. While a grip is active, press Enter or Space to step through the other grip modes: STRETCH, MOVE, ROTATE, SCALE and MIRROR. Type C to make copies instead of moving the original, B to choose another base point, and X to stop.

Right-click a polyline’s grip for a menu of what that grip can do, such as adding or removing a vertex.

Move, copy and transform

These commands select objects, then ask for a base point and a second point. The objects move or copy by the distance and direction between the two.

Command	Type	What it does
MOVE	M	Move selected objects a specified distance and direction.
COPY	CO, CP	Duplicate selected objects at a specified offset.
ROTATE	RO	Rotate selected objects around a base point.
SCALE	SC	Resize selected objects uniformly about a base point.
MIRROR	MI	Create a mirror-image copy of objects across an axis.
STRETCH	S	Move the parts of objects inside a crossing window, keeping the rest anchored.
ARRAY	AR	Create a rectangular, path or polar pattern of copies.
ALIGN	AL	Move, rotate and optionally scale a selection onto two destination points.
MOCORO	MOCORO	Move, rotate and scale the selection in one command, with copies if asked.
ERASE	E	Delete selected objects from the drawing.
OOPS	OOPS	Bring back the objects the last ERASE removed, keeping everything done since.

Change shapes

Command	Type	What it does
TRIM	TR	Trim objects to meet the edges of other objects.
EXTEND	EX	Extend objects to meet the edges of other objects.
OFFSET	O	Create a parallel copy of a curve at a specified distance.
FILLET	F	Round corners between two intersecting lines, arcs, or polylines.
CHAMFER	CHA	Bevel corners between two intersecting lines.
BREAK	BR	Break a curve between two points.
BREAKATPOINT	BREAKATPOINT	Split a curve at one point, leaving no gap.
JOIN	J	Join collinear or connected objects into a single object.
LENGTHEN	LEN	Change the length of a line or arc.
EXPLODE	X	Break compound objects into their components.
PEDIT	PE	Edit a polyline, or several (Multiple): close/open, join, width, vertices, fit, spline, decurve, reverse.
SPLINEDIT	SPE	Edit a spline: its control points, reverse it, or make it a polyline.
REVERSE	REVERSE	Make lines, polylines and splines run the other way.
OVERKILL	-OVERKILL	Delete duplicate objects and combine overlapping collinear lines.

TRIM and EXTEND are the two you will use most. Both start in Quick mode, where every object is an edge and you just click the part to cut off or lengthen. Hold Shift to switch between them while you work.

Change properties

Every object has a layer, a colour, a linetype, a lineweight and more. Usually these come from its layer (“ByLayer”).

• The Properties palette (PR) shows the properties of the selection and lets you change any of them.
• Match Properties (MA) copies properties from one object to others.
• To move objects to another layer, select them and change Layer in the Properties palette, or use LAYMCH to match the layer of an object you pick.

Command	Type	What it does
PROPERTIES	PR, CH, PROPS	Open the Properties palette to view and edit object properties.
MATCHPROP	MA, PAINTER	Copy properties from a source object to one or more target objects.
CHPROP	CHPROP	Change objects' colour, layer, linetype, linetype scale or lineweight at the command line.
CHANGE	-CH	Change lines' ends, circles' radii, texts and blocks by a point, or their properties.
COPYTOLAYER	COPYTOLAYER	Copy objects to another layer, in place or moved.
DRAWORDER	DR	Draw the objects selected over or under the rest: Front, Back, or above or under objects you pick.

Undo and redo

Ctrl+Z or U undoes the last command. Redo puts it back. Inside many commands, such as LINE and TRIM, the Undo option takes back just the last step without leaving the command.

Command	Type	What it does
U	UNDO	Reverse the most recent action.
REDO	REDO	Redo the last step undone.
MREDO	MREDO	Redo several undone steps, or all of them.

Next

• Place points exactly while you edit with Precision and drafting aids.
• Keep a drawing tidy with layers and blocks in Organising a drawing.