<HTML> <HEAD> <!-- This HTML file has been created by texi2html 1.51 from .././gimpprint.texi on 22 January 2003 --> <TITLE>GIMP-Print - Weaving collisions</TITLE> </HEAD> <BODY> Go to the <A HREF="gimpprint_1.html">first</A>, <A HREF="gimpprint_30.html">previous</A>, <A HREF="gimpprint_32.html">next</A>, <A HREF="gimpprint_47.html">last</A> section, <A HREF="gimpprint_toc.html">table of contents</A>. <P><HR><P> <H3><A NAME="SEC46" HREF="gimpprint_toc.html#TOC46">B.2.3 Weaving collisions</A></H3> <P> <A NAME="IDX186"></A> <A NAME="IDX187"></A> </P> <P> This perfect weave is not possible in all cases. Let's look at another example: </P> <P> @math{S=6}, @math{J=4}: </P> <PRE> 0 *-----*-----*-----* 1 *-----*-----*-----* 2 *-----*-----*-----* 3 *-----*-----*-----* 4 ^ *-^---*-----*-----* 5 | ^ | *-^---*-----*-----* OUCH! ^ | ^ | | </PRE> <P> Here we have a collision. Some lines printed in later passes overprint lines printed by earlier passes. We can see why by considering which row number is printed by a given jet number @math{j} (numbered from 0) of a given pass, @math{p}: </P> <PRE> @math{row(p, j) = p*J + j*S} </PRE> <P> Because @math{J=4} and @math{S=6} have a common factor of 2, jet 2 of pass 0 prints the same row as jet 0 of pass 3: </P> <PRE> @math{row(0, 2) = 0*4 + 2*6 = 12} @math{row(3, 0) = 3*4 + 0*6 = 12} </PRE> <P> In fact, with this particular weave pattern, jets 0 and 1 of pass @math{p+3} always overprint jets 2 and 3 of pass @math{p}. We'll represent overprinting rows by a <SAMP>`^'</SAMP> in our diagrams, and correct rows by <SAMP>`*'</SAMP>: </P> <P> @math{S=6} @math{J=4}: </P> <PRE> 0 *-----*-----*-----* 1 *-----*-----*-----* 2 *-----*-----*-----* 3 ^-----^-----*-----* 4 ^-----^-----*-----* 5 ^-----^-----*-----* </PRE> <P><HR><P> Go to the <A HREF="gimpprint_1.html">first</A>, <A HREF="gimpprint_30.html">previous</A>, <A HREF="gimpprint_32.html">next</A>, <A HREF="gimpprint_47.html">last</A> section, <A HREF="gimpprint_toc.html">table of contents</A>. </BODY> </HTML>