Remote-processing RPC-2350 Manuel d'utilisateur télécharger pdf (Page 66)

CHAPTER 15 GRAPHIC DISPLAY PORT

15-5

Scroll up time may be an important factor. It takes

about 65 mS to move all 1160 characters of the text up

one line.

CHANGING AND LOADING FONTS

Medium and lar ge size char acter fonts are stor ed in

Flash EPROM U3. You can change or customize the

fonts using the supplied programs and a Windows bitmap

graphics program (such as PC Paint Brush).

If U3 is missing, damaged or W11 is removed, garbage

characters will be displayed.

You can change and load fonts using the programs

supplied in the demo disk. They are under the FONT

director y. Su pplied are all of the .BMP files used to

create each character. They are named as Lxxx.BM P or

Mxxx.BM P. A n ‘L’ prefix specifies a large character

and an ‘M’ prefix is for medium. The num ber following

this letter is the ASCII value. Thus, M65. BMP is a

medium sized letter ‘A’

Modification instructions are in a READM E file in the

directory. Read this if you want to modify the

characters..

Characters sizes are fixed at 10 x 16 for medium and 32

x 48 for large.

DRAWING POINTS AND LINES

There are two basic commands used for drawing lines

and points:

DISPLAY LINE

DISPLAY P

Both commands have a counter part to clear lines and

points:

CLEAR DISPLAY LINE

CLEAR DISPLAY P

Drawing range is from 0,0 to 329,239. Coordinates are

shown in the figure below.

Figure 15-2

The demo progr am CIRC LE. BAS draws a circle using

point set (DISPLAY P(x,y)).

Minimal range checking is performed. If a point does

not show up or is in the wrong place, chances are either

the X or Y param eter is wrong.

CLEAR, FILL, AND XOR AREAS

You can clear (erase), fill, or XOR (toggle) a

rectangular area using one of the display com mands.

DISPLAY F(x1, y1),(x2, y2) Fills an area

DISPLAY F, C(x1, y1),(x2, y2) Clears an area

DISPLAY F, X(x1,y1), (x2,y2) Toggles an area

This com mand is use ful when you want to selectively

clear or fill an area (graphics, for example) without

clearing the entire screen. F illing an area is useful for

displaying a bar graph. It is faster than drawing lines.

XOR is useful when you want to highlight an area. The

data is reversed in whatever area is selected.

The fill com mand takes time to execute, especially in

large areas. This is important if you are running

multitasking (ON COM , ON BIT, etc. ).

Display fill operates fastest when X is on an 8 bit

boundary. For exam ple, filling an area bounded by

(0,y), (96,y) is 20% faster than (1,y),(97,y), even though

the area is the same. XOR requires an extra 20% more

time to execute. Turning off sparkle (see ear lier in this

chapter) reduces write time by about ½.

Execution time depends upon the size of the ar ea to fill.

Larger areas obviously take more time than sm all ones.

1 2 ... 61 62 63 64 65 66 67 68 69 70 71 ... 82 83

Commentaires sur ces manuels

Pas de commentaire

Remote-processing RPC-2350 Manuel d'utilisateur Page 66

Commentaires sur ces manuels

Produits connexes et manuels pour Ordinateurs Remote-processing RPC-2350