Add a table of zoom level precisions to the documentation

README.md

@@ -323,6 +323,29 @@ Parallel processing will also be automatic if the input file is in Geobuf format
  * `-R` _zoom_`/`_x_`/`_y_ or `--one-tile=`_zoom_`/`_x_`/`_y_: Set the minzoom and maxzoom to _zoom_ and produce only
    the single specified tile at that zoom level.
 
+If you know the precision to which you want your data to be represented,
+this table shows the approximate precision corresponding to various
+`-z` options if you use the default `-d` detail of 12:
+
+zoom level | precision (ft) | precision (m)
+---------- | -------------- | -------------
+`-z0` | 32000 ft | 10000 m
+`-z1` | 16000 ft | 5000 m
+`-z2` | 8000 ft | 2500 m
+`-z3` | 4000 ft | 1250 m
+`-z4` | 2000 ft | 600 m
+`-z5` | 1000 ft | 300 m
+`-z6` | 500 ft | 150 m
+`-z7` | 250 ft | 80 m
+`-z8` | 125 ft | 40 m
+`-z9` | 64 ft | 20 m
+`-z10` | 32 ft | 10 m
+`-z11` | 16 ft | 5 m
+`-z12` | 8 ft | 2 m
+`-z13` | 4 ft | 1 m
+`-z14` | 2 ft | 0.5 m
+`-z15` | 1 ft | 0.25 m
+
 ### Tile resolution
 
  * `-d` _detail_ or `--full-detail=`_detail_: Detail at max zoom level (default 12, for tile resolution of 2^12=4096)

man/tippecanoe.1

@@ -385,6 +385,48 @@ specified maximum zoom and to any levels added beyond that.
 \fB\fC\-R\fR \fIzoom\fP\fB\fC/\fR\fIx\fP\fB\fC/\fR\fIy\fP or \fB\fC\-\-one\-tile=\fR\fIzoom\fP\fB\fC/\fR\fIx\fP\fB\fC/\fR\fIy\fP: Set the minzoom and maxzoom to \fIzoom\fP and produce only
 the single specified tile at that zoom level.
 .RE
+.PP
+If you know the precision to which you want your data to be represented,
+this table shows the approximate precision corresponding to various
+\fB\fC\-z\fR options\fB\fCif you use the default\fR\-d` detail of 12:
+.TS
+allbox;
+cb cb cb
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+l l l
+.
+zoom level	precision (ft)	precision (m)
+\fB\fC\-z0\fR	32000 ft	10000 m
+\fB\fC\-z1\fR	16000 ft	5000 m
+\fB\fC\-z2\fR	8000 ft	2500 m
+\fB\fC\-z3\fR	4000 ft	1250 m
+\fB\fC\-z4\fR	2000 ft	600 m
+\fB\fC\-z5\fR	1000 ft	300 m
+\fB\fC\-z6\fR	500 ft	150 m
+\fB\fC\-z7\fR	250 ft	80 m
+\fB\fC\-z8\fR	125 ft	40 m
+\fB\fC\-z9\fR	64 ft	20 m
+\fB\fC\-z10\fR	32 ft	10 m
+\fB\fC\-z11\fR	16 ft	5 m
+\fB\fC\-z12\fR	8 ft	2 m
+\fB\fC\-z13\fR	4 ft	1 m
+\fB\fC\-z14\fR	2 ft	0.5 m
+\fB\fC\-z15\fR	1 ft	0.25 m
+.TE
 .SS Tile resolution
 .RS
 .IP \(bu 2