1 files changed, 46 insertions, 0 deletions
diff --git a/src/layout.zig b/src/layout.zig
index 09cf23b3..16af1ec5 100644
--- a/src/layout.zig
+++ b/src/layout.zig
@@ -441,6 +441,52 @@ pub fn minimaFit(p: *Pardes) bool {
     return true;
 }
 
+/// Whether every unfolded pane of column `c` has its `minRows` (a pane
+/// alone in its column always does).
+pub fn columnAtMinimums(p: *Pardes, c: usize) bool {
+    compute(p);
+    if (p.col_n[c] < 2) return true;
+    for (p.col_panes[c][0..p.col_n[c]]) |k| {
+        const pane = p.panes[k] orelse continue;
+        if (!pane.collapsed and p.rects[k].h < minRows(p, k)) return false;
+    }
+    return true;
+}
+
+/// Shares column `c`'s rows out again so every unfolded pane has its
+/// `minRows`, as evenly as that allows; false, changing nothing, when the
+/// column has not the rows for all of them (or holds a folded pane).
+pub fn shareColumn(p: *Pardes, c: usize) bool {
+    compute(p);
+    const n = p.col_n[c];
+    if (n == 0) return false;
+    const avail = p.screen_h -| (p.topBarHeight() + p.columnBarHeight());
+    var mins: [MAX_PANES]u16 = undefined;
+    var need: u32 = 0;
+    for (p.col_panes[c][0..n], 0..) |k, i| {
+        const pane = p.panes[k] orelse return false;
+        if (pane.collapsed) return false;
+        p.rects[k].w = p.col_w[c];
+        mins[i] = minRows(p, k);
+        need += mins[i];
+    }
+    if (need > avail) return false;
+    // Each its minimum, then what is left a row at a time to the smallest.
+    var hs: [MAX_PANES]u16 = undefined;
+    @memcpy(hs[0..n], mins[0..n]);
+    var left = avail - need;
+    while (left > 0) : (left -= 1) {
+        var low: usize = 0;
+        for (1..n) |i| if (hs[i] < hs[low]) {
+            low = i;
+        };
+        hs[low] += 1;
+    }
+    for (p.col_panes[c][0..n], 0..) |k, i| p.panes[k].?.vweight = @floatFromInt(hs[i]);
+    compute(p);
+    return true;
+}
+
 /// After a resize the minima fit: each unfolded pane the resize took below
 /// its `minRows` (it had them in `before`) gets them back, a row at a time
 /// from whichever pane of its column has the most above its own. A pane