2. Changing Tips and Module Maps

The following commands are provided for specifying the ;SPMlt;object;SPMgt; to be used when typesetting various parts of the twocells.



command
default


||;SPMlt;object;SPMgt;||


These commands set the object to be used for all subsequent 2-cells at the same level of TEX grouping. || specifies both of the upper- and lower-curve objects. For some of these there is also a way to change the object for the current 2-cell only. This requires a |~|-;SPMlt;option;SPMgt; which is described below, except for the |.̇curveobject| types, which are discussed in <#430#>Extra Options~4<#430#>.


These effects are specified by placing options after the |.̇twocell| control sequence, ||<#431#>options<#431#> <#432#>labels<#432#>...~. Each option is either a single token ;SPMlt;tok;SPMgt;, or a |~|;SPMlt;tok;SPMgt; with a single argument: |~|;SPMlt;tok;SPMgt;|<#982#>|<#433#>arg<#433#>|<#982#>|. Possibilities are listed in the following table, in which |<#434#>..<#434#>| denotes the need for an argument.


#defs1435#

Here we discuss the use of |!|, |~'|, |~`| and ||. The description of |~^|, |~_| and |~<#448#>..<#448#>| is given in <#449#>Extra Options~4<#449#>.


The default module map indicator places a single dash crossing the arrow at right-angles, located roughly midway along the actual printed portion of the arrow, whether curved or straight. This takes into account the sizes of the objects being connected, thereby giving an aesthetic result when these sizes differ markedly. This also works with |.̇compositemap| where an indicator is placed on each arrow. The actual object can be changed using ||.


Any of the standard -pic tips may be used for arrow-heads. This is done using |~'<#450#>..<#450#>|, for example |~'<#983#><#451#>;SPMgt;;SPMgt;<#451#><#983#>| gives double-headed arrows. Similarly |~`<#452#>..<#452#>| can be used to place an arrow-tail. Normally the arrow-tail is <#453#><#453#>, so is not placed; but if a non-empty tail has been specified then it will be placed, using ||. No guarantee is offered for the desired result being obtained when an arrow-tail is mixed with the features of <#454#>Extra Options~1<#454#>.


#code455#

#math459#

#tex2html_wrap_indisplay1766#

2 option for module maps... ...places decoration called || half way along arrows

( @@<#987#>205 4@4=<#464#>!<#464#>206 4=4=<#465#>H<#465#>207 4^4=<#466#>A<#466#>208 4_4=<#467#>V<#467#> @<#468#>6<#468#>209 @ @<#987#> )

also adjust curvature and label positions

( @@<#1108#>210 @6@ @=@ @7@ @;SPMlt;@@.5@@-.5@ @ @8@ @;SPMlt;@@-.5@@.5@ 3t@-1@ @ @;SPMlt;@@-.5@@.5@ @ @7@ @;SPMlt;@@-.5@@.5@ 3t@-2@ @ @8@ @;SPMlt;@@-.5@@.5@ 3t@-2@ @ <#1108#>214

)

default object is ||, user can change this with |#1|

( @#1<#993#><#993#> @@ <#994#><#475#>|<#475#><#994#> @modmapobject@<#995#><#476#>mod@@ <#476#><#995#> )

3