fix: implementation of absc mode for pipe layers that don't update Gx.xstart/Gx.xdelta as part of basefile

Author: maihde

js/sigplot.js

@@ -8606,11 +8606,19 @@
  Gx.iabsc = 2;
  } // R/I mode
  if (Gx.iabsc === 1) { // index
- Gx.aretx = Math.round((Gx.aretx - Gx.xstart) / Gx.xdelta);
+ // if there is more than one layer index is ambiguous, so use the first layer only
+ var hcb = plot.get_hcb_by_lyrn(0);
+ if (hcb) {
+ Gx.aretx = Math.round((Gx.aretx - hcb.xstart) / hcb.xdelta);
+ Gx.dretx = Math.round(Gx.dretx / hcb.xdelta);
+ } else {
+ Gx.aretx = 0;
+ Gx.dretx = 1;
+ }
  if (!Gx.index) {
  Gx.aretx += 1;
  }
-  Gx.dretx = Math.round(Gx.dretx / Gx.xdelta);
+ 
  } else if (Gx.iabsc === 2) { // 1/absc
  if (Gx.aretx !== 0.0) {
  Gx.aretx = 1.0 / Gx.aretx;