REFDIS is used only in the LONGLIBR version of the longlib graphics library. It is a dummy call for other versions. REFDIS is a non-interactive method of specifying the output device (REF file, terminal screen, or LONGLIB metafile) to be used for outputing the REF bit-map Ramtek image array. When called prior to PLOTND, it outputs the array to the device specified in the call without user intervention. When REFDIS is not called prior to PLOTND, PLOTND will call REFDIS and the user will be prompted for the output device and option. Note: REFDIS may be called multiple times to output to several devices.
When the internal REF data array is output to the terminal or metafile output each line of the internal array is scanned left to right. Connected pixels having the same color are collected and plotted (using PLOT) to the output device. Pixels with 0 value are not output. The pixel-to-inch output scaling can be user selected to correspond to the actual hardware resolution of the output device. Normal resolution for the terminal output is 9.5/1024 inch/pixel (most terminals do not actually have this resolution). Normal resolution for the metafile output is 1/300 inch/pixel. Hence, at normal resolution, the 1280x1024 pixel REF array more than fills the terminal screen. The pixel image is output with the lower-left corner at (0,0). By changing the origin prior to call the user can display any desired portion of the image.
CALL REFDIS(id,ot,n,rx,ry)
id (I): Output device
=-1 : graphics terminal number code (see FRAME)
user-specified (rx,ry) used
= 1 : graphics terminal number code (see FRAME)
default resolution used
= 2 : Ramtek emulation file (REF)
(ot = 1 : absolute file write)
(ot = 2 : write out only non-zero pixels)
(ot = 3 : write out only zero pixels)
=-3 : LONGLIB metafile output
user-specified (rx,ry) used
= 3 : LONGLIB metafile output
default resolution used
ot (I): Output option code (see above)
n (C): REF file name
rx,ry (R): user-specified output resolution (inch/pixel)