From 6bdb1f413e4c592f73d91bef33dfb202503ef7ab Mon Sep 17 00:00:00 2001
From: Viktor <vlofgren@gmail.com>
Date: Tue, 10 Jun 2025 09:20:31 +0200
Subject: [PATCH] dwindle: add the ability to specify an aspect ratio for a
 singular window (#10650)

---
 src/config/ConfigDescriptions.hpp | 12 +++++++++++
 src/config/ConfigManager.cpp      |  2 ++
 src/layout/DwindleLayout.cpp      | 36 +++++++++++++++++++++++++------
 3 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/src/config/ConfigDescriptions.hpp b/src/config/ConfigDescriptions.hpp
index 1eff8c63c..7d62c8338 100644
--- a/src/config/ConfigDescriptions.hpp
+++ b/src/config/ConfigDescriptions.hpp
@@ -1782,6 +1782,18 @@ inline static const std::vector<SConfigOptionDescription> CONFIG_OPTIONS = {
         .type        = CONFIG_OPTION_BOOL,
         .data        = SConfigOptionDescription::SBoolData{false},
     },
+    SConfigOptionDescription{
+        .value       = "dwindle:single_window_aspect_ratio",
+        .description = "If specified, whenever only a single window is open, it will be coerced into the specified aspect ratio.  Ignored if the y-value is zero.",
+        .type        = CONFIG_OPTION_VECTOR,
+        .data        = SConfigOptionDescription::SVectorData{{0, 0}, {0, 0}, {1000., 1000.}},
+    },
+    SConfigOptionDescription{
+        .value       = "dwindle:single_window_aspect_ratio_tolerance",
+        .description = "Minimum distance for single_window_aspect_ratio to take effect, in fractions of the monitor's size.",
+        .type        = CONFIG_OPTION_FLOAT,
+        .data        = SConfigOptionDescription::SFloatData{0.1f, 0.f, 1.f},
+    },
 
     /*
      * master:
diff --git a/src/config/ConfigManager.cpp b/src/config/ConfigManager.cpp
index 8dc06d77c..6759771c6 100644
--- a/src/config/ConfigManager.cpp
+++ b/src/config/ConfigManager.cpp
@@ -595,6 +595,8 @@ CConfigManager::CConfigManager() {
     registerConfigVar("dwindle:smart_split", Hyprlang::INT{0});
     registerConfigVar("dwindle:smart_resizing", Hyprlang::INT{1});
     registerConfigVar("dwindle:precise_mouse_move", Hyprlang::INT{0});
+    registerConfigVar("dwindle:single_window_aspect_ratio", Hyprlang::VEC2{0, 0});
+    registerConfigVar("dwindle:single_window_aspect_ratio_tolerance", {0.1f});
 
     registerConfigVar("master:special_scale_factor", {1.f});
     registerConfigVar("master:mfact", {0.55f});
diff --git a/src/layout/DwindleLayout.cpp b/src/layout/DwindleLayout.cpp
index 305f1feed..2f51b162b 100644
--- a/src/layout/DwindleLayout.cpp
+++ b/src/layout/DwindleLayout.cpp
@@ -152,15 +152,39 @@ void CHyprDwindleLayout::applyNodeDataToWindow(SDwindleNodeData* pNode, bool for
 
     PWINDOW->updateWindowDecos();
 
-    auto       calcPos  = PWINDOW->m_position;
-    auto       calcSize = PWINDOW->m_size;
+    auto              calcPos  = PWINDOW->m_position;
+    auto              calcSize = PWINDOW->m_size;
 
-    const auto OFFSETTOPLEFT = Vector2D((double)(DISPLAYLEFT ? gapsOut.m_left : gapsIn.m_left), (double)(DISPLAYTOP ? gapsOut.m_top : gapsIn.m_top));
+    const static auto REQUESTEDRATIO          = *CConfigValue<Hyprlang::VEC2>("dwindle:single_window_aspect_ratio");
+    const static auto REQUESTEDRATIOTOLERANCE = CConfigValue<Hyprlang::FLOAT>("dwindle:single_window_aspect_ratio_tolerance");
 
-    const auto OFFSETBOTTOMRIGHT = Vector2D((double)(DISPLAYRIGHT ? gapsOut.m_right : gapsIn.m_right), (double)(DISPLAYBOTTOM ? gapsOut.m_bottom : gapsIn.m_bottom));
+    Vector2D          ratioPadding;
 
-    calcPos  = calcPos + OFFSETTOPLEFT;
-    calcSize = calcSize - OFFSETTOPLEFT - OFFSETBOTTOMRIGHT;
+    if (REQUESTEDRATIO.y != 0 && !pNode->pParent) {
+        const Vector2D originalSize = PMONITOR->m_size - PMONITOR->m_reservedTopLeft - PMONITOR->m_reservedBottomRight;
+
+        const double   requestedRatio = REQUESTEDRATIO.x / REQUESTEDRATIO.y;
+        const double   originalRatio  = originalSize.x / originalSize.y;
+
+        if (requestedRatio > originalRatio) {
+            double padding = originalSize.y - (originalSize.x / requestedRatio);
+
+            if (padding / 2 > (*REQUESTEDRATIOTOLERANCE) * originalSize.y)
+                ratioPadding = Vector2D{0., padding};
+        } else if (requestedRatio < originalRatio) {
+            double padding = originalSize.x - (originalSize.y * requestedRatio);
+
+            if (padding / 2 > (*REQUESTEDRATIOTOLERANCE) * originalSize.x)
+                ratioPadding = Vector2D{padding, 0.};
+        }
+    }
+
+    const auto GAPOFFSETTOPLEFT = Vector2D((double)(DISPLAYLEFT ? gapsOut.m_left : gapsIn.m_left), (double)(DISPLAYTOP ? gapsOut.m_top : gapsIn.m_top));
+
+    const auto GAPOFFSETBOTTOMRIGHT = Vector2D((double)(DISPLAYRIGHT ? gapsOut.m_right : gapsIn.m_right), (double)(DISPLAYBOTTOM ? gapsOut.m_bottom : gapsIn.m_bottom));
+
+    calcPos  = calcPos + GAPOFFSETTOPLEFT + ratioPadding / 2;
+    calcSize = calcSize - GAPOFFSETTOPLEFT - GAPOFFSETBOTTOMRIGHT - ratioPadding;
 
     if (PWINDOW->m_isPseudotiled) {
         // Calculate pseudo