Error(s) in re-building vignettes:
--- re-building ‘Isochrones.Rmd’ using rmarkdown
Pandoc is required to build R Markdown vignettes but not available. Please make sure it is installed.
Checking rgeos availability: TRUE
Please note that 'maptools' will be retired by the end of 2023,
plan transition at your earliest convenience;
some functionality will be moved to 'sp'.
rgeos version: 0.5-8, (SVN revision 679)
 GEOS runtime version: 3.8.1-CAPI-1.13.3 
 Please note that rgeos will be retired by the end of 2023,
plan transition to sf functions using GEOS at your earliest convenience.
 Linking to sp version: 1.4-5 
 Polygon checking: TRUE 

Warning in sp::proj4string(obj) :
  CRS object has comment, which is lost in output
Warning in sp::proj4string(obj) :
  CRS object has comment, which is lost in output

Attaching package: 'smoothr'

The following object is masked from 'package:stats':

    smooth

Warning in sp::proj4string(x) :
  CRS object has comment, which is lost in output
Warning in proj4string(obj) :
  CRS object has comment, which is lost in output
Warning in sp::proj4string(obj) :
  CRS object has comment, which is lost in output
--- finished re-building ‘Isochrones.Rmd’

--- re-building ‘KNetworkFunctions.Rmd’ using rmarkdown
Pandoc is required to build R Markdown vignettes but not available. Please make sure it is installed.
--- finished re-building ‘KNetworkFunctions.Rmd’

--- re-building ‘NKDE.Rmd’ using rmarkdown
Pandoc is required to build R Markdown vignettes but not available. Please make sure it is installed.
Checking rgeos availability: TRUE
Please note that 'maptools' will be retired by the end of 2023,
plan transition at your earliest convenience;
some functionality will be moved to 'sp'.
rgeos version: 0.5-8, (SVN revision 679)
 GEOS runtime version: 3.8.1-CAPI-1.13.3 
 Please note that rgeos will be retired by the end of 2023,
plan transition to sf functions using GEOS at your earliest convenience.
 Linking to sp version: 1.4-5 
 Polygon checking: TRUE 

Warning in proj4string(sldf) :
  CRS object has comment, which is lost in output

Attaching package: 'dplyr'

The following objects are masked from 'package:raster':

    intersect, select, union

The following objects are masked from 'package:rgeos':

    intersect, setdiff, union

The following object is masked from 'package:kableExtra':

    group_rows

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Warning in proj4string(sldf) :
  CRS object has comment, which is lost in output
Warning: Removed 5028 row(s) containing missing values (geom_path).
--- finished re-building ‘NKDE.Rmd’

--- re-building ‘NKDEdetailed.Rmd’ using rmarkdown
Pandoc is required to build R Markdown vignettes but not available. Please make sure it is installed.
Loading required package: sp
rgeos version: 0.5-8, (SVN revision 679)
 GEOS runtime version: 3.8.1-CAPI-1.13.3 
 Please note that rgeos will be retired by the end of 2023,
plan transition to sf functions using GEOS at your earliest convenience.
 Linking to sp version: 1.4-5 
 Polygon checking: TRUE 

Checking rgeos availability: TRUE
Please note that 'maptools' will be retired by the end of 2023,
plan transition at your earliest convenience;
some functionality will be moved to 'sp'.

Attaching package: 'rgl'

The following object is masked from 'package:rgeos':

    triangulate

Warning in snapshot3d(scene = x, width = width, height = height) :
  webshot = TRUE requires the webshot2 package; using rgl.snapshot() instead
Quitting from lines 163-164 (NKDEdetailed.Rmd) 
Error: processing vignette 'NKDEdetailed.Rmd' failed with diagnostics:
OpenGL is not available in this build
--- failed re-building ‘NKDEdetailed.Rmd’

--- re-building ‘NetworkBuilding.Rmd’ using rmarkdown
Pandoc is required to build R Markdown vignettes but not available. Please make sure it is installed.
Checking rgeos availability: TRUE
Please note that 'maptools' will be retired by the end of 2023,
plan transition at your earliest convenience;
some functionality will be moved to 'sp'.
rgeos version: 0.5-8, (SVN revision 679)
 GEOS runtime version: 3.8.1-CAPI-1.13.3 
 Please note that rgeos will be retired by the end of 2023,
plan transition to sf functions using GEOS at your earliest convenience.
 Linking to sp version: 1.4-5 
 Polygon checking: TRUE 

Warning in RGEOSBinPredFunc(spgeom1, spgeom2, byid, func) :
  spgeom1 and spgeom2 have different proj4 strings
Warning in RGEOSBinPredFunc(spgeom1, spgeom2, byid, func) :
  spgeom1 and spgeom2 have different proj4 strings
Warning in RGEOSBinPredFunc(spgeom1, spgeom2, byid, func) :
  spgeom1 and spgeom2 have different proj4 strings
Warning in proj4string(points) :
  CRS object has comment, which is lost in output
Warning in sp::proj4string(obj) :
  CRS object has comment, which is lost in output
Warning in sp::proj4string(obj) :
  CRS object has comment, which is lost in output
Warning in sp::proj4string(obj) :
  CRS object has comment, which is lost in output
Warning in sp::proj4string(obj) :
  CRS object has comment, which is lost in output
--- finished re-building ‘NetworkBuilding.Rmd’

--- re-building ‘SpatialWeightMatrices.Rmd’ using rmarkdown
Pandoc is required to build R Markdown vignettes but not available. Please make sure it is installed.
--- finished re-building ‘SpatialWeightMatrices.Rmd’

SUMMARY: processing the following file failed:
  ‘NKDEdetailed.Rmd’

Error: Vignette re-building failed.
Execution halted