From 7949032411153ebf9d87b0e936b1bc288df12b38 Mon Sep 17 00:00:00 2001
From: Xaver Hugl <xaver.hugl@gmail.com>
Date: Mon, 22 Apr 2024 22:25:29 +0200
Subject: [PATCH] outputconfigurationstore: don't overwrite output settings
 with kscreen configs

The existing code overwrites all per-output data with the config from KScreen
every time an output config is found that isn't in the KWin data base yet.
That causes problems like the scale being reset to 1.0 if the user logged
into Xorg before, or resetting it to whatever scale KScreen had saved on
Wayland, which isn't much better.

Instead of doing that, use the KScreen config as inspiration for some specific
output settings, instead of copying it outright. It's not ideal, but it's
better than overwriting settings the user has explicitly set up

BUG: 485353
---
 src/outputconfigurationstore.cpp | 39 ++++++++++++++++++++------------
 1 file changed, 24 insertions(+), 15 deletions(-)

diff --git a/src/outputconfigurationstore.cpp b/src/outputconfigurationstore.cpp
index 77ebb69dd3..f207002dce 100644
--- a/src/outputconfigurationstore.cpp
+++ b/src/outputconfigurationstore.cpp
@@ -52,12 +52,6 @@ std::optional<std::tuple<OutputConfiguration, QList<Output *>, OutputConfigurati
         storeConfig(relevantOutputs, isLidClosed, config, order);
         return std::make_tuple(config, order, ConfigType::Preexisting);
     }
-    if (auto kscreenConfig = KScreenIntegration::readOutputConfig(relevantOutputs, KScreenIntegration::connectedOutputsHash(relevantOutputs, isLidClosed))) {
-        auto &[config, order] = *kscreenConfig;
-        applyOrientationReading(config, relevantOutputs, orientation, isTabletMode);
-        storeConfig(relevantOutputs, isLidClosed, config, order);
-        return std::make_tuple(config, order, ConfigType::Preexisting);
-    }
     auto [config, order] = generateConfig(relevantOutputs, isLidClosed);
     applyOrientationReading(config, relevantOutputs, orientation, isTabletMode);
     storeConfig(relevantOutputs, isLidClosed, config, order);
@@ -397,12 +391,16 @@ std::pair<OutputConfiguration, QList<Output *>> OutputConfigurationStore::genera
             return *closedConfig;
         }
     }
+    const auto kscreenConfig = KScreenIntegration::readOutputConfig(outputs, KScreenIntegration::connectedOutputsHash(outputs, isLidClosed));
     OutputConfiguration ret;
     QList<Output *> outputOrder;
     QPoint pos(0, 0);
     for (const auto output : outputs) {
+        const auto kscreenChangeSetPtr = kscreenConfig ? kscreenConfig->first.constChangeSet(output) : nullptr;
+        const auto kscreenChangeSet = kscreenChangeSetPtr ? *kscreenChangeSetPtr : OutputChangeSet{};
+
         const auto outputIndex = findOutput(output, outputs);
-        const bool enable = !isLidClosed || !output->isInternal() || outputs.size() == 1;
+        const bool enable = kscreenChangeSet.enabled.value_or(!isLidClosed || !output->isInternal() || outputs.size() == 1);
         const OutputState existingData = outputIndex ? m_outputs[*outputIndex] : OutputState{};
 
         const auto modes = output->modes();
@@ -411,19 +409,21 @@ std::pair<OutputConfiguration, QList<Output *>> OutputConfigurationStore::genera
                 && mode->size() == existingData.mode->size
                 && mode->refreshRate() == existingData.mode->refreshRate;
         });
-        const auto mode = modeIt == modes.end() ? output->currentMode() : *modeIt;
+        const auto mode = modeIt == modes.end() ? kscreenChangeSet.mode.value_or(output->currentMode()).lock() : *modeIt;
 
         const auto changeset = ret.changeSet(output);
         *changeset = {
             .mode = mode,
-            .enabled = enable,
+            .enabled = kscreenChangeSet.enabled.value_or(enable),
             .pos = pos,
+            // kscreen scale is unreliable because it gets overwritten with the value 1 on Xorg,
+            // and we don't know if it's from Xorg or the 5.27 Wayland session... so just ignore it
             .scale = existingData.scale.value_or(chooseScale(output, mode.get())),
-            .transform = existingData.transform.value_or(output->panelOrientation()),
-            .manualTransform = existingData.manualTransform.value_or(output->panelOrientation()),
-            .overscan = existingData.overscan.value_or(0),
-            .rgbRange = existingData.rgbRange.value_or(Output::RgbRange::Automatic),
-            .vrrPolicy = existingData.vrrPolicy.value_or(VrrPolicy::Automatic),
+            .transform = existingData.transform.value_or(kscreenChangeSet.transform.value_or(output->panelOrientation())),
+            .manualTransform = existingData.manualTransform.value_or(kscreenChangeSet.transform.value_or(output->panelOrientation())),
+            .overscan = existingData.overscan.value_or(kscreenChangeSet.overscan.value_or(0)),
+            .rgbRange = existingData.rgbRange.value_or(kscreenChangeSet.rgbRange.value_or(Output::RgbRange::Automatic)),
+            .vrrPolicy = existingData.vrrPolicy.value_or(kscreenChangeSet.vrrPolicy.value_or(VrrPolicy::Automatic)),
             .highDynamicRange = existingData.highDynamicRange.value_or(false),
             .sdrBrightness = existingData.sdrBrightness.value_or(200),
             .wideColorGamut = existingData.wideColorGamut.value_or(false),
@@ -435,7 +435,16 @@ std::pair<OutputConfiguration, QList<Output *>> OutputConfigurationStore::genera
             outputOrder.push_back(output);
         }
     }
-    return std::make_pair(ret, outputs);
+    if (kscreenConfig && kscreenConfig->second.size() == outputOrder.size()) {
+        // make sure the old output order is consistent with the enablement states of the outputs
+        const bool consistent = std::ranges::all_of(outputOrder, [&kscreenConfig](const auto output) {
+            return kscreenConfig->second.contains(output);
+        });
+        if (consistent) {
+            outputOrder = kscreenConfig->second;
+        }
+    }
+    return std::make_pair(ret, outputOrder);
 }
 
 std::shared_ptr<OutputMode> OutputConfigurationStore::chooseMode(Output *output) const