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Graphical Printing |
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The PxPlus environment includes several PRINT destinations for handling true graphical (bitmap/vector) data. The standard interface to the Windows print manager, *WINPRT*, is designed for printing a hard copy from graphical output. Other options include *PDF*, *VIEWER* and *BITMAP*.
Graphical mode is not just for images - the graphical capabilities of the PxPlus environment allow applications to deliver many more printing options than from a strictly character-based environment. Because graphical printing is page-oriented rather than line-oriented, the line positioning (column/row) is dynamic. PxPlus applications that are set up to print or display graphical output can access any part of the page at any time - top-to-bottom ordering is not required.
PxPlus also allows you to mix and match fonts and attributes, apply graphical mnemonics, as well as maintain older Character-Based Printing formats, all on the same page.
All graphical printing from a PxPlus application requires the use of specific API calls to the Windows print manager - only certain predefined graphical mnemonics are mapped to Windows API calls for this purpose; e.g. 'ARC', 'CIRCLE', 'FONT', 'FRAME', 'LINE', 'PICTURE', 'PIE', 'POLYGON', 'RECTANGLE' and 'TEXT'.
See Mnemonic Categories for a complete list of mnemonics. In this list, the graphical mnemonics are identified by the GUI Display and GUI Printer categories.
Positioning within a graphical mnemonic requires the use of X and Y coordinates. These are often derived using the @X( ) / @Y( ) functions, which convert column and row values into graphical units. When a graphical mnemonic is applied against a channel, the channel number should be passed as an argument to the @X( ) / @Y( ) functions. The following routine illustrates how to use some of the mnemonics available for printing graphics in PxPlus:
! Printing Graphics
PRINT 'CS',
ch=UNT ! OPEN (ch)"*viewer*"
PRINT (ch)'FONT'("Times New Roman",3,"BI"),'BLUE',
PRINT (ch)'TEXT'(@X(0,ch),@Y(0,ch),@X(70,ch),@Y(5,ch),"Printing Graphics","C"),
PRINT (ch)'PEN'(1,2,4),'ARC'(@X(7,ch),@Y(5,ch),@X(1,ch),1,0,180),
PRINT (ch)'PEN'(1,3,1),'FILL'(1,4),'RECTANGLE'(@X(2,ch),@Y(9,ch),@X(12,ch),@Y(13,ch)),
PRINT (ch)'PEN'(1,1,7),'LINE'(@X(2.5,ch),@Y(9.5,ch),@X(11.5,ch),@Y(9.5,ch),@X(11.5,ch),@Y(12.5,ch),@X(2.5,ch),@Y(12.5,ch),@X(2.5,ch),@Y(9.5,ch)),
PRINT (ch)'PEN'(1,2,4),'FILL'(7,1),'CIRCLE'(@X(54,ch),@Y(10,ch),@X(6,ch),1.8), L=@X(24,ch),R=@X(33,ch),S=@X(4,ch),X=@Y(6,ch),Y=@Y(14,ch)
PRINT (ch)'PEN'(1,3,2),'FILL'(1,12),'POLYGON'(L-S*2,X,R+S*4,Y,L,Y,R-S,X,L,X),
PRINT (ch)'PICTURE'(@X(0,ch),@Y(15,ch),@X(30,ch),@Y(25,ch),"*win/nomads2",2),
You can use all foreground and background colours with colour printers. Use the 'PEN' and 'FILL' mnemonics to control the colour settings for graphics mnemonics.
The following routine prints each of the available 16 colours:
0010 ! Colour Printing
0020 FONT$="MS Sans Serif",COLS_REQD=80
0030 CHAN=UNT; OPEN (CHAN)"*WINPRT*"
0040 PRINT (CHAN)'FONT'(FONT$,-12),'DF', ! Set base to 10 CPI
0050 CUR_COL=MXC(CHAN)+1; IF CUR_COL=0 THEN CUR_COL=80
0060 INCHES_WIDE=CUR_COL/10
0070 PRINT (CHAN)'FONT'(FONT$,CUR_COL/COLS_REQD),'DF',
0080 PRINT (CHAN)'CPI'(COLS_REQD/INCHES_WIDE),'LPI'(6),
0090 FOR Z=0 TO 15
0100 INTENSITY$=TBL(Z>7,"","Light ")
0110 COLOUR$=TBL(MOD(Z,8),"Black","Red","Green","Yellow","Blue","Magenta","Cyan","White")
0120 COLOUR_MNEM$=ESC+"F"+CHR(ASC("0")+Z)
0130 PRINT (CHAN)@(0),COLOUR_MNEM$,INTENSITY$,COLOUR$
0140 NEXT