.. index::
   single: Modifying Objects

Modifying Objects
=================

Select one or more objects first, then apply a Modify command from the
**Modify menu**, the **Modify ribbon tab**, or the keyboard.

.. index::
   single: Modify Commands

Modify Commands
---------------

.. list-table::
   :header-rows: 1
   :widths: 18 20 62

   * - Command
     - Shortcut / Alias
     - Description
   * - **Erase**
     - Del · ``E``
     - Deletes all selected objects.  If no objects are selected, prompts
       "Select objects:" — pick objects then right-click to confirm or press
       Escape to cancel.
   * - **Move**
     - ``M``
     - Enter a displacement as ``X,Y`` in the command line, or pick two
       reference points on the canvas.
   * - **Copy**
     - ``CO``
     - Creates copies of selected objects.  Enter displacement the same way
       as Move.
   * - **Rotate**
     - ``RO``
     - Enter a rotation angle in degrees (positive = counter-clockwise).
   * - **Scale**
     - ``SC``
     - Enter a uniform scale factor.  Values > 1 enlarge; values < 1 shrink.
   * - **Offset**
     - ``O``
     - Creates a parallel copy of an entity at a specified distance.
       Supports Line, Circle, Arc, XLine, Polyline, Ellipse, Spline, and
       Rectangle.  The default distance is stored in ``OFFSETDIST``.
       Options: **T** = through point, **E** = erase source, **U** = undo.
       A phantom preview shows the offset entity while picking the side.
   * - **Mirror**
     - ``MI``
     - Pick two points to define the mirror axis.  Optionally delete the
       original.
   * - **Trim**
     - ``TR``
     - Two-phase: select cutting edges (or type ``ALL``), then click objects to
       trim.  Supports Line, Arc, Polyline, Ellipse, and Spline entities.
   * - **Extend**
     - ``EX``
     - Two-phase: select boundary edges, then click the end of an entity to
       extend it.  Supports Line, Arc, Polyline, Ellipse, and Spline entities.
   * - **Chamfer**
     - ``CHA``
     - Pick two lines to chamfer.  Use the ``D`` sub-option to set chamfer
       distances (``$CHAMFERA`` / ``$CHAMFERB``).  The second distance defaults
       to the first.  Zero distance trims to the intersection.
   * - **Fillet**
     - ``F``
     - Pick two lines to fillet with an arc.  Use the ``R`` sub-option to set
       the radius (``$FILLETRAD``).  Zero radius trims to the intersection.
   * - **Explode**
     - (none)
     - Breaks compound objects into their component entities.  Blocks are
       exploded into individual entities; multilines into separate lines;
       polyface meshes into individual 3D Face entities.
   * - **Break**
     - ``BR``
     - Breaks an entity between two points.  Pick the object (the pick point
       is the first break point), then "Specify second break point or
       [First point]:" — type ``F`` to re-pick the first point, or ``@`` to
       break at a single point with no gap.  Lines, arcs and polylines split
       into two entities (or are shortened at an end); a circle becomes an
       arc; closed polylines become one open polyline.  A single undo step
       restores everything.
   * - **Join**
     - ``J``
     - Joins lines, arcs and polylines.  Collinear touching lines merge into
       one line; touching arcs on the same circle merge into one arc; other
       touching chains merge into a polyline, preserving arc segments as true
       bulge (curved) segments.  Reports "N object(s) joined into M."
   * - **Align**
     - ``AL``
     - Aligns objects using one or two source/destination point pairs.  The
       first pair translates; a second pair adds rotation (press Enter after
       the first pair to move only).  Then prompts "Scale objects based on
       alignment points? [Yes/No] <No>".  Objects picked as the destination
       reference are not affected.
   * - **Divide**
     - ``DIV``
     - Places point entities dividing an entity into a specified number of
       equal segments (2–32767).  Open entities get N−1 interior points;
       closed entities (circles, closed polylines) get N points.  Works on
       lines, polylines, arcs, circles, ellipses, and splines.
   * - **Measure**
     - ``ME``
     - Places point entities along an entity at a fixed interval, starting
       from the end nearest the pick point.  The final partial segment is
       left as-is.  Supports the same entity types as Divide.
   * - **Array**
     - ``ARR``
     - Rectangular, polar or path array of the selected objects.  Prompts
       "Enter array type [Rectangular/Polar/PAth] <Rectangular>".
       Rectangular: rows, columns, row/column spacing (negative spacing
       allowed).  Polar: centre point, item count, angle to fill <360>,
       rotate items Yes/No.  Path: pick a path entity, choose Divide (count)
       or Measure (spacing) placement, and whether to align items with the
       path.  Creates plain copies.  The alias is ``ARR`` because ``AR`` is
       used by the Arrow tool.
   * - **PEDIT**
     - ``PE``
     - Edit a polyline: Close/Open, Join, Width, Edit vertex, Spline, Decurve,
       Reverse.  Converts Lines, Arcs and Circles to polylines.  Supports 2D and 3D
       polylines.

.. note::

   **FLATTEN** (project to Z = 0) lives under **Super Tools → Cleanup**,
   not Modify.  See :doc:`../super_tools/02_cleanup`.

.. index::
   single: Mesh and Surface Conversion
   single: Mesh
   single: Surface Conversion

Mesh and Surface Conversion
---------------------------

.. list-table::
   :header-rows: 1
   :widths: 18 20 62

   * - Command
     - Alias
     - Description
   * - **Mesh2Surface**
     - ``M2S``
     - Converts a selected polyface mesh entity into a TIN surface.  The
       mesh vertices become surface points and the mesh faces become TIN
       triangles.  Prompts for a surface name (defaults to the mesh layer
       name).  The original mesh entity is preserved.
   * - **Surface2Mesh**
     - ``S2M``
     - Converts a TIN surface into a polyface mesh entity on the canvas.
       Prompts for the surface name (auto-selects if only one surface
       exists).  The resulting mesh can be exported to DXF as a standard
       polyface mesh, exploded into 3D Faces, or moved/copied like any
       other drawing entity.

.. index::
   single: Clipboard

Clipboard
---------

IQcad supports clipboard operations for copying entities between drawings and
between separate IQcad instances.  Entities are serialised to the system
clipboard as IQML (IQcad's XML format), so all entity types are preserved
including civil objects, survey points, and their associated layers.

.. list-table::
   :header-rows: 1
   :widths: 22 18 60

   * - Command
     - Shortcut
     - Description
   * - **COPYCLIP**
     - Ctrl+C
     - Copies the selected entities to the clipboard from whichever tab is
       active (model or a layout).  Associated layers and survey points are
       included automatically, along with the source space and drawing scale
       so a later paste can auto-scale.
   * - **CUT**
     - Ctrl+X
     - Copies the selected entities to the clipboard, then deletes them from
       the drawing, from whichever tab is active.  Associated layers and
       survey points are included automatically, along with the source space
       and drawing scale so a later paste can auto-scale.
   * - **PASTECLIP**
     - Ctrl+V
     - Pastes clipboard contents onto whichever tab is active (model or a
       layout).  A ghost of the entities follows the cursor; click (or type
       ``x,y``) to place them, Esc, a right-click, or pressing Enter on an
       empty command line cancels.  Missing layers
       are created automatically.  Civil point numbers are renumbered if they
       conflict with existing points in the target drawing.  Pasting between
       model and a layout auto-scales by the drawing scale, so text and
       tables land at the size they plot at (e.g. a 1:500 drawing scales
       ×2 into paper mm).  Viewports are never carried across the
       clipboard — copying leaves them out, so any other entities in the
       same selection paste normally and a viewport-only copy has nothing
       to paste.
   * - **PASTEORIG**
     - Ctrl+Shift+V
     - Pastes clipboard contents at their original coordinates instead of
       the cursor position.  Same auto-scaling as **PASTECLIP**, but
       non-interactive.

.. tip::
   Because the clipboard uses the system clipboard, you can copy entities in
   one IQcad instance, switch to a completely separate IQcad window, and paste
   them there.

.. index::
   single: OSNAP in Edit Commands

OSNAP in Edit Commands
----------------------

MOVE, COPY, ROTATE, SCALE, and OFFSET use OSNAP when picking reference
points and destinations.  During the object-selection phase of these commands,
OSNAP is temporarily disabled so that snapping does not interfere with object
picking.

.. index::
   single: Grips

Grips
-----

When objects are selected, **blue grip handles** appear at key points (endpoints,
midpoints, centres).  Drag a grip to move or reshape the object interactively
without invoking a Modify command.

.. index::
   single: Undo and Redo
   single: Undo
   single: Redo

Undo and Redo
-------------

- **Ctrl+Z** — undo the last action.
- **Ctrl+Y** — redo.

The undo history is per-drawing and is preserved as long as the drawing tab
remains open.