add a bit of docs

one_line_gen.tal

@@ -1,8 +1,9 @@
 |00 @System &vector $2 &expansion $2 &wst $1 &rst $1 &metadata $2 &r $2 &g $2 &b $2 &debug $1 &state $1
 |10 @Console &vector $2 &read $1 &pad $4 &type $1 &write $1 &error $1
 |a0 @File/vector $2 &success $2 &stat $2 &delete $1 &append $1 &name $2 &length $2 &read $2 &write $2
+
 %dbug  { #01 .System/debug DEO }
-%print { .Console/write DEO  }
+
 (
     Portable BitMap
     https://en.wikipedia.org/wiki/Netpbm#File_formats
@@ -36,7 +37,6 @@
     #0a write-to-image
     ( image data )
     load-drawing
-    ( get first 8 pixels )
     #1f ;/y STA
     &y-loop
         #58 ;/x STA
@@ -64,7 +64,7 @@
 	&y $1
 	&x $1
 
-
+( take 8 01 / 00 off the stack and create a byte with them )
 @build-byte ( p p p p p p p p )
     LITr 00 ( p p p p p p p p | 00 )
     ?{ LITr 01 ORAr }
@@ -85,6 +85,7 @@
     STHr
     JMP2r
 
+( given a pixel x,y figure out if it is part of the drawing )
 @get-pixel (  x y  ->  bool )
     ,/y STR ( x )
     ,/x STR ( )
@@ -110,9 +111,7 @@
     &x $1
     &y $1
 
-( @remove-offset )
-
-
+( load .1line drawing file from disk to memory )
 @load-drawing
     ;/filename .File/name DEO2
     ;drawing-size .File/length DEO2
@@ -120,6 +119,7 @@
 	JMP2r
     &filename "footer.1line $1
 
+( write a single byte to the image buffer )
 @write-to-image ( val )
     ;img-pt LDA2 ( val pt* )
     STA ( )
@@ -128,6 +128,7 @@
     ;img-pt STA2
     JMP2r
 
+( save the image buffer to disk )
 @save-file
 	;/filename .File/name DEO2
 	;image-size .File/length DEO2