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wheel to zoom and pan in your drawing without using any commands. When zooming in, the

location near your cursor is the focal point of the zoom and thus remains on the screen.
Roll the wheel forward - Zoom In

Roll the wheel backward - Zoom Out
Double-click the wheel button - Zoom Extents

Hold down the wheel button and drag the mouse - Pan
Press and hold the SHIFT key and the wheel button and drag the mouse - Constrained Orbit.

2.7 COORDINATE SYSTEM

Every object you draw is placed in either the world coordinate system (WCS) or a user coordinate

system (UCS). When you create 2D geometry, data input is ultimately passed to the software in the
form of Cartesian (x,y) or polar coordinates (distance, angle). You can either manually enter these

coordinates or infer them by picking a point in the drawing window.

Absolute and Relative Coordinates
When you type coordinates, they can be in the form of an absolute or a relative coordinate.

An absolute coordinate represents a specific point in the current coordinate system relative to the

origin point (0,0). To enter an absolute coordinate, type the values as a Cartesian coordinate (x,y)
or Polar coordinate (distance angle).

A relative coordinate is a point located from a previously selected point. To enter a relative
coordinate, select your first point, then precede the next coordinate point with the @ symbol. For

example @5<45 would mean 5 units at 45 degrees from the last point selected, and @3,5 would
mean 3 units in the positive x direction and 5 units in the positive y direction from the last point

selected.

Absolute and Relative Coordinate Examples
Coordinate Absolute Relative

Cartesian Coordinate 10,5 @10,5
Polar Coordinate 10<45 @10<45

Amal Jyothi College of Engineering 11