nixos/patches/hyprland-dwindle-pin-far-sides.patch

--- a/src/layout/algorithm/tiled/dwindle/DwindleAlgorithm.cpp
+++ b/src/layout/algorithm/tiled/dwindle/DwindleAlgorithm.cpp
@@ -297,6 +297,56 @@
     recalculate();
 }
 
+// Moving a split only changes that node's ratio, so every split nested on
+// either side of it gets rescaled and edges that weren't dragged slide along.
+// Record the size of each region that doesn't touch the moved edge, so it can
+// be pinned afterwards and only the windows along the edge absorb the resize.
+struct SFarSide {
+    SP<SDwindleNodeData> node;
+    bool                 farIsSecond = false;
+    float                size        = 0;
+};
+using FarSides = std::vector<SFarSide>;
+
+static void collectFarSides(const SP<SDwindleNodeData>& node, bool vertical, bool edgeAtStart, FarSides& out) {
+    if (!node || !node->children[0] || !node->children[1])
+        return;
+
+    const auto C0 = node->children[0].lock();
+    const auto C1 = node->children[1].lock();
+
+    if (node->splitTop == vertical) {
+        // split along the resize axis: pin the far child, follow the near one
+        const auto FARCHILD = edgeAtStart ? C1 : C0;
+        out.push_back({node, edgeAtStart, (float)(vertical ? FARCHILD->box.h : FARCHILD->box.w)});
+        collectFarSides(edgeAtStart ? C0 : C1, vertical, edgeAtStart, out);
+    } else {
+        // perpendicular split: both children touch the edge
+        collectFarSides(C0, vertical, edgeAtStart, out);
+        collectFarSides(C1, vertical, edgeAtStart, out);
+    }
+}
+
+static FarSides collectFarSides(const SP<SDwindleNodeData>& split, bool vertical) {
+    FarSides out;
+    collectFarSides(split->children[0].lock(), vertical, false, out);
+    collectFarSides(split->children[1].lock(), vertical, true, out);
+    return out;
+}
+
+// parents come before their children in `far`, so each node's box is already
+// final by the time its own ratio is recomputed
+static void restoreFarSides(const FarSides& far, bool vertical, bool force) {
+    for (const auto& [node, farIsSecond, size] : far) {
+        const float TOTAL = vertical ? node->box.h : node->box.w;
+        if (TOTAL <= 0)
+            continue;
+
+        node->splitRatio = std::clamp(farIsSecond ? 2.f - size / TOTAL * 2.f : size / TOTAL * 2.f, 0.1F, 1.9F);
+        node->recalcSizePosRecursive(force);
+    }
+}
+
 void CDwindleAlgorithm::resizeTarget(const Vector2D& Δ, SP<ITarget> target, eRectCorner corner) {
     if (!validMapped(target->window()))
         return;
@@ -356,6 +406,8 @@
         }
 
         if (PHOUTER) {
+            const auto HFAR = collectFarSides(PHOUTER->pParent.lock(), false);
+
             PHOUTER->pParent->splitRatio = std::clamp(PHOUTER->pParent->splitRatio + allowedMovement.x * 2.f / PHOUTER->pParent->box.w, 0.1, 1.9);
 
             if (PHINNER) {
@@ -368,9 +420,13 @@
                 PHINNER->pParent->recalcSizePosRecursive(*PANIMATE == 0);
             } else
                 PHOUTER->pParent->recalcSizePosRecursive(*PANIMATE == 0);
+
+            restoreFarSides(HFAR, false, *PANIMATE == 0);
         }
 
         if (PVOUTER) {
+            const auto VFAR = collectFarSides(PVOUTER->pParent.lock(), true);
+
             PVOUTER->pParent->splitRatio = std::clamp(PVOUTER->pParent->splitRatio + allowedMovement.y * 2.f / PVOUTER->pParent->box.h, 0.1, 1.9);
 
             if (PVINNER) {
@@ -383,6 +439,8 @@
                 PVINNER->pParent->recalcSizePosRecursive(*PANIMATE == 0);
             } else
                 PVOUTER->pParent->recalcSizePosRecursive(*PANIMATE == 0);
+
+            restoreFarSides(VFAR, true, *PANIMATE == 0);
         }
     } else {
         // get the correct containers to apply splitratio to