TR - Transparency mode ; TR [ - Page 184

2001/10/02 

CHAPTER 4 HP-GL/2 - 36 

• 

With screen type 21 

option 1

 specifies one of six predefined PCL cross-hatch patterns (patterns 1 - 6).  

option 2

 is ignored. 

• 

With screen type 22,  

option 1

 specifies the ID number of PCL user-defined pattern which is defined by the 

ESC*c#W command.  

option 2

 is ignored. 

• 

With fill screen type 130 

option 1

 specifies the percentage of shading ( 0 - 100 ):  

option 2

 is ignored. 

• 

If 

option 1

 and 

option 2 

are omitted,  the most recently specified values for these parameters, for the 

specified screen type, are used. 

• 

All screening patterns use the current anchor corner. 

• 

Invoking the command with no parameter turns screening off.  This is equivalent to SV0; 

10 '-Screened Vectors- 

20 WIDTH "LPT1:", 255 

30 LPRINT CHR$(27); "E"; 

40 LPRINT CHR$(27); "%0B"; 

50 LPRINT "IN;SP1;"; 

60 LPRINT "SV1,15;PA4000,5000;CI500;" 

70 LPRINT "SV1,50;PA5000,4000;CI400;" 

80 LPRINT "SV1,100;PA6000,6000;CI300;" 

90 LPRINT "PW10;SV21,5;PA2000,1000;PD;AA0,0,90;PC;" 

100 LPRINT "PW5;SV21,3;PA6000,6000;CI500;" 

110 LPRINT "PW7;SV21,6;PA2000,8000;PDPA5000,8000;PU;" 

120 LPRINT "PW7;SV21,6;PA2000,8000;PDPA5000,8000;PU;" 

130 LPRINT "1,1,0,0,0,0,0,0,1,1,"; 

140 LPRINT "0,0,1,1,0,0,1,1,0,0,"; 

150 LPRINT "0,0,0,0,1,1,0,0,0,0,"; 

160 LPRINT "0,0,1,1,0,0,1,1,0,0,"; 

170 LPRINT "1,1,0,0,0,0,0,0,1,1;"; 

180 LPRINT 

"PW15;SV2,3;PA4000,2000;PM0;PD6000,2000,6000,4000,4000,4000;PM1;PM2;EP;

" 

190 LPRINT CHR$(27); "%0A"; 

200 LPRINT CHR$(27); "E"; 

210 END 

<Sample 44> 

TR - Transparency mode 

TR [ 

n

 ] [;] 

n

 ; transparency type 

• 

This command turns transparency mode on and off.  Transparency mode defines how source and 
destination graphics images interact. 

• 

n

 is either 0 (off) or 1(on). 

• 

When transparency mode is on, the white parts of a s ource image (the image that is being superimposed on 
the destination image) do not affect the destination image - that is,  part of the destination image will be 
visible beneath the source image. 

• 

When transparency mode is off the destination image is not v isible beneath the source image. 

• 

Invoking the command with no parameter turns transparency mode on.  This is equivalent to TR1; 

• 

An Esc E reset,  a control panel reset,  the IN command and the DF command all turn transparency mode 
on. 

10 'Transparency Mode- 

20 WIDTH "LPT1:", 255 

30 LPRINT CHR$(27); "E"; 

40 LPRINT CHR$(27); "%0b"; 

50 LPRINT "IN;SP1;"; 

60 'PART1 TR1 

70 'Original Destination 1 

80 LPRINT "TR1;PA1900,4900;PM0;PM3100;4900,2500,6100;PM1;" 

90 LPRINT "PM2;FP;" 

100 'Source 1 

110 LPRINT "FT10,50;PA2000,5000;RR500,500;PA2500,5500;RR500,500;" 

120 LPRINT "FT10,1;PA2500,5000;RR500,500;PA2000,5500;RR500,500;FT;" 

130 'PART2 TR0 

140 'Original Destination 2