1 files changed, 42 insertions, 0 deletions
diff --git a/util.c b/util.c
new file mode 100644
index 0000000..4594a9a
--- /dev/null
+++ b/util.c
@@ -0,0 +1,42 @@
+#include <u.h>
+#include <libc.h>
+#include <thread.h>
+#include <draw.h>
+#include <mouse.h>
+#include <keyboard.h>
+#include <geometry.h>
+#include "dat.h"
+#include "fns.h"
+
+static char rowtab[] = "abcdefghijklmnopq";
+
+
+char *
+cell2coords(Point2 cell)
+{
+	static char s[3+1];
+
+	assert(cell.x < 17 && cell.x >= 0
+		&& cell.y < 17 && cell.y >= 0);
+
+	snprint(s, sizeof s, "%c%d", rowtab[(int)cell.y], (int)cell.x);
+	return s;
+}
+
+Point2
+coords2cell(char *s)
+{
+	Point2 cell;
+	char *p;
+
+	assert(s[0] >= 'a' && s[0] <= 'q');
+
+	cell = Pt2(0,0,1);
+	p = strchr(rowtab, s[0]);
+	cell.y = p-rowtab;
+	cell.x = strtol(s+1, nil, 10);
+
+	assert(cell.x < 17 && cell.x >= 0);
+
+	return cell;
+}