CHAPTER 1 - OVERVIEW

1.1 INTRODUCTION

Figure 1.1 Example of a Program using XDL_VIEW

In developing the software, the basic requirements were considered to be as follows:

1. To use X-windows.

2. To make use of a colour display.

3. To provide 'high level' view-objects for easy use in building application software.

4. To be able to set up and manipulate such objects via Fortran callable routines (as well as providing a C interface).

5. To provide code which would be portable across a range of workstations with a certain minimum specification.

6. To enable view-objects to appear in individual windows or to be laid out in a tiled fashion on a larger window.

7. To provide a means for specifying the view-objects from which the application is prepared to accept input at any particular time.

8. To provide documentation to cover user and programmer requirements.

List of sections:

Documentation
Some Terms Used
Defining Fonts

1.2 DOCUMENTATION

The documentation available covers the XDL_VIEW routines from a number of different stand points. These are:-

1. The person using an application program which makes use of the view-objects.

2. The application programmer who wants to use the available view-objects from within his/her Fortran or C program.

3. The programmer who wishes to develop new view-objects for general or specific requirements.

• Volume 1: User Documentation (this volume)

• Volume 2: Programmer's Guide

• Volume 3: XDL_VIEW Routine Calls

The application programmer will need to be familiar with the material in the first half of Volume 2 and will use the reference material in the first half of Volume 3.

The second halves of Volumes 2 and 3 are for the programmer who wishes to write new view-objects or who wishes to understand more about the design of the XDL_VIEW routines.

1.3 SOME TERMS USED

Some of the terms used in describing the operation of the view objects are as follows:

Point to:

Means move the mouse so that the pointer or cursor on the screen points to the position referred to.

Click a Button:

Press and release a button on the mouse.

Hold down a Button:

Press a button on the mouse and hold it down as directed, possibly while moving the position of the mouse.

Release a Button:

Release a Button which has been held down as described above.

Button1:

Button 1 of the mouse, normally the left hand button.

Button2:

Button 2 of the mouse, normally the middle button of a three button mouse.

Button3:

Button 3 of the mouse, normally the right hand button of a three button mouse.

1.4 DEFINING FONTS

Fonts will normally be defined as X-windows resources Xdl*font1...Xdl*font5 and Xdl*boldFont1...Xdl*boldFont5. There are five normal and five bold fonts. These should normally be fixed width fonts. Each series must be in ascending size order. Bold fonts must match normal fonts to within 1 pixel in width and two in height. Some of the view-objects assume that the small font does not exceed 7x13 in pixels in size; a warning will be output if this size is exceeded.

The following is an example of specifing the fonts as X-windows resources:

Xdl*font1:  -adobe-courier-medium-r-normal--10-100-75-75-m-60-iso8859-1
Xdl*font2:  -adobe-courier-medium-r-normal--12-120-75-75-m-70-iso8859-1
Xdl*font3:  -adobe-courier-medium-r-normal--14-140-75-75-m-90-iso8859-1
Xdl*font4:  -adobe-courier-medium-r-normal--18-180-75-75-m-110-iso8859-1
Xdl*font5:  -adobe-courier-medium-r-normal--24-240-75-75-m-150-iso8859-1

Xdl*boldFont1:  -adobe-courier-bold-r-normal--10-100-75-75-m-60-iso8859-1
Xdl*boldFont2:  -adobe-courier-bold-r-normal--12-120-75-75-m-70-iso8859-1
Xdl*boldFont3:  -adobe-courier-bold-r-normal--14-140-75-75-m-90-iso8859-1
Xdl*boldFont4:  -adobe-courier-bold-r-normal--18-180-75-75-m-110-iso8859-1
Xdl*boldFont5:  -adobe-courier-bold-r-normal--24-240-75-75-m-150-iso8859-1