Linear Dimensions

You don't need to specify whether the linear dimension you want to draw is horizontal or vertical. AutoCAD infers the direction when you specify the first point.

Dynamic Editing

You can reposition dimension components dynamically using standard AutoCAD editing commands.

Mainstream Dimension Commands

Individual dimensioning commands such as DIMLINEAR and DIMCONTINUE are available at the same level as other AutoCAD commands rather than as options of the DIM command.

Associative Hatching

Associative hatching is hatching that is tied to its defining geometry. When you change the geometry, the hatch pattern automatically adapts to the changes.

Hatch Editing

Use the new HATCHEDIT command to change hatch patterns, angles, spacing, and so on, without having to erase and redo the hatch.

Boundary Hatching

The HATCH command automatically detects interior shapes and text in the objects to be hatched. The HATCH command has a new option called Direct. You can use it to draw and hatch a polyline with a single command.

New Object Snaps

Release 13 includes three new object snaps: Extended Intersection, Apparent Intersection, and Relative Point.

EXTEND, LENGTHEN, and TRIM

Enhancements to the EXTEND and TRIM commands allow you to extend and trim objects to their implied intersection with other objects. The new LENGTHEN command extends a line a specified length, by a percentage, or dynamically.

FILLET and CHAMFER

Release 13 adds the ability to fillet parallel lines. You can fillet or chamfer intersecting lines and polylines.

Object Grouping

You can group objects together with the new GROUP command. Grouped objects are logically related and are selected together as one object. With this command, you can create named selection sets.

New Objects

Earlier releases of AutoCAD approximated an ellipse by drawing a polyline through the points you specified. You can draw a true geometrical ellipse. Release 13 has a new SPLINE command to draw true splines defined as NURBS (Non-Uniform Rational B-Spline) curves. Grips work with both splines and ellipses.

Multiple Parallel Lines

Multiple parallel lines or multilines consist of up to sixteen parallel lines, offset from one another by a distance you specify. You can specify the properties of each line element and control intersections, corner joints, and end caps. You can also clean up the intersections of multilines after you draw them.

Construction Geometry

Construction geometry support consists of two new AutoCAD commands, XLINE and RAY. Xlines and rays are lines that extend to infinity in one or both directions. You can use them as a reference to create other objects by creating temporary construction lines to snap to. Xlines and rays have no effect on the extents of the drawing. Zooming and changing the view has no effect on them.

Linetype Enhancements

Linetypes have been extended to incorporate shapes and text. The linetypes that come with AutoCAD include a full set of ISO standard linetypes. You can apply a linetype scaling factor to individual objects.

Native AutoCAD Solids

Solid modeling is a quick way to build 3D models. You can make interference or other volume calculations, or add and subtract volumes to create new solids. Solids are represented as native AutoCAD objects. They behave like other AutoCAD objects and compute faster than AME (AutoCAD Modeling Extension) solids. Release 13 has a new command to convert AME models to AutoCAD solid objects.

Solid Primitives

Solid primitives are the basic building blocks that make up more complex solid models. AutoCAD Release 13 includes six primitives: box, sphere, cone, cylinder, wedge, and torus.

Boolean Operations

Boolean operations create a composite solid from two or more solids.

Swept Solids

You can also create new solids by extruding an object (adding height) or by revolving an object (sweeping about an axis).

Rendering Enhancements

Rendering enhancements in Release 13 include the following:
+   Spotlights
+   Colored lights
+   Light attenuation
+   Phong and Gouraud rendering
+   Wide variety of file formats for saved images
+   3D Studio file import and export