TR - Transparency mode ; TR [ - Page 192

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 source 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 visible 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 
150 LPRINT "TR0;PA3900,4900;PM0;PA5100,4900,4500,6100;PM1;" 
160 LPRINT "PM2;FP;"