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Installation
Hand Held Products' PadCom Library comes bundled as a set of static libraries with operating system dependent (MS-
®
DOS
, WIN16, and WIN32
is part of the Software Development Kit (SDK) which is available in 16-bit or 32-bit versions, and is included on the
Transaction Team 1500 and Transaction Team 3100 Series software suite CDs. The SDK installation program is a simple
®
to use InstallShield
application. It allows you to selectively install the desired components and sample programs. Please
refer to the Startup Guide you received with your hardware for instructions on software installation. For further information
on other components of the SDK, see the SDK Roadmap document which is available upon installation of the SDK.
Transaction Team Device Overview
The device's pad surface is composed of a large number of individual points or "pixels," as are video monitors, printers and
other devices. Because the library is designed to maintain the integrity of the input points, it does NOT distort the image by
adjusting for squareness. Therefore, when using points obtained, it is important to understand both the mapping of the pad
surface and the concept of aspect ratios. In addition, the methods used to represent pen strokes must be considered.
The points on the pad are specified by using a pair of horizontal and vertical coordinates (referred to as X and Y coordinates,
respectively). The origin of the coordinates is at the top/left corner and increases in a positive direction toward the bottom/
right. Therefore, the coordinate pair "0,0" is at top/left corner; "0,100" is 100 points down, "100,0" is 100 points to the right;
and "100,100" is both 100 points to the right and 100 points down. The actual coordinates of the bottom/right corner can be
represented as padWidth()-1, padHeight()-1, or obtained by using the padGetArea function (page 3-10).
Aspect Ratio Considerations
Since the points returned by the library represent the actual points on the physical pad device, it is necessary to understand
the concept of "aspect ratios." Basically, an aspect ratio refers to the difference between the width and height of the physical
points. For example, a 1:1 ratio means that the width and height of a point are the same and that the point is perfectly square.
Similarly, an aspect ratio of 2:1 means that a point is twice as wide as it is high. This is important because a shape that
appears square when created at, for example, a 2:1 aspect ratio, will appear vertically stretched when viewed at an aspect
ratio of 1:1. The aspect ratio of the pad surface is represented by the ratio between horizontal and vertical "dots-per-inch"
and can be obtained by using the functions padHorzDPI (page 3-23), and padVertDPI (page 3-66), respectively. To
maintain proper aspect ratios when drawing the points on the screen or other device, the library provides functions such as
padScaleDPI (page 3-47) to facilitate aspect ratio adjustment.
Representing Pen Strokes
While a single point consists of a single horizontal and vertical coordinate, a pen stroke consists of all the points received
from the time the pen comes into contact with the pad through the time it is removed. A typical stroke contains many points.
The first point, referred to as a "moveto" point, indicates where the pen was first placed in contact with the pad. Remaining
points, referred to as "lineto" points, indicate that the pen is being dragged across the pad surface. Consequently, the
padGet function (page 3-9) retrieves a "moveto/lineto" pen indicator as well as the corresponding coordinates.
1 - 2
®
) and compiler dependent (Microsoft
x0,y0
x0,y100
®
®
and Borland
) solutions available for your use. PadCom
x100,y0
Y
x100,y100
X
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