fouts@INETG1.ARCO.COM ("Chris L. Fouts 754-3298") (08/29/90)
In message <9008272215.AA25131@max>; from "Harmon J. Zuccola" on Aug 27, 90 6:15 pm, Harmon writes: > > 3) How do you get rid of those little grey dots, when you know > you should have a white background [on PostScript plots]? > I assume you are using the tops program. The source for this program is included in /usr/people/4Dgifts/iristools/imgtools. The problem is in the rgbrowtobw routine at the bottom of the file. Change the following line *obuf++ = (77*(*rbuf++) + 150*(*gbuf++) + 28*(*bbuf++))>>8; to *obuf++ = (77*(*rbuf++) + 150*(*gbuf++) + 29*(*bbuf++))>>8; ^^ and re-compile it. As it is, any white pixels (rbuf=gbuf=bbuf=255) cause obuf to be loaded with the value of 254 instead of 255. The printer prints out this "almost-white" color using a very light dither pattern, resulting in the black dots. -------------------------------------------------------------------------------- Chris L. Fouts Email: fouts@inetg1.arco.com Systems Engineer Phone: 214-754-3850 Silicon Graphics Computer Systems -------------------------------------------------------------------------------- "I have never seen anything fill up a vacuum so fast and still suck." - Rob Pike on X --------------------------------------------------------------------------------