feat(colitur-x): fill the window instead of a fixed grid

Cell size is now computed from the window -- width divided seven ways,
height six -- and the number of lines a feast name gets is whatever fits
the resulting cell. config.h holds minimums rather than sizes.

Under a tiling window manager the calendar now uses its whole tile. It
previously drew a fixed 196x116 grid and left the rest of the tile black,
which is what every screenshot of it has shown.

The size hint is now PREFERRED plus MINIMUM, never fixed. Pinning it
fought the WM, which ignored it anyway, and stopped the grid using a
larger tile.

Added -g WxH, the same flag st takes, mainly because it makes the reflow
testable: verified at 1365x687 (two name lines) and 1852x1024 (three).

1 files changed, 7 insertions, 0 deletions

diff --git a/README.md b/README.md
index 6530ec9..476a818 100644
--- a/README.md
+++ b/README.md
@@ -14,8 +14,15 @@ presentation choice and belongs in a viewer: colitur's own kernel is pure
 and deliberately never asks what day it is, which is what lets it be tested
 to the year 9999.
 
+    colitur-x -g 1200x820 < day.csv          # preferred size, if the WM allows
     CX_DUMP=/tmp/f.ppm colitur-x < day.csv   # write one frame, then exit
 
+The grid **fills whatever size it is given**: cell width is the window
+divided seven ways, cell height six ways, and the number of lines a feast
+name gets is whatever fits. Under a tiling window manager it therefore uses
+its whole tile rather than sitting in a corner of one, and resizing reflows
+instead of clipping. `config.h` sets minimums, not sizes.
+
 It reads CSV on **stdin** and nothing else, so the shell decides what it
 shows. One month: