Support UltraWide screens

1 files changed, 28 insertions, 1 deletions

diff --git a/src/xprivate.cpp b/src/xprivate.cpp
index 70c1a3f..950c6ce 100644
--- a/src/xprivate.cpp
+++ b/src/xprivate.cpp
@@ -149,7 +149,7 @@ void XPrivate::updateScreenResources()
                     continue;
             }
             bool disconnected = false;
-            if (info->crtc == None) {
+            if (info->crtc == None && info->connection == RR_Connected) {
                     disconnected = true;
                     qDebug() << "Connected output" << outputName << "has no CRTC -- trying to find free one";
                     info->crtc = getFreeCrtc(info);
@@ -375,9 +375,36 @@ XRRModeInfo* XPrivate::getPreferredMode(OutputInfo *oi, XRRModeInfo *fallback) c
                 return nullptr; // WTF!?
         }
         RRMode mode;
+        // H4xx0r - Ultrawide screens seem to incorrectly report a 16:9 resultion as their preferred one
+        // I can only guess this is a safety measure for old/bad OS or gfx cards
+        // So, determine the aspect ratio by looking at the physical size and if it's ultrawide, look for a
+        // more fitting resolution in the list of supported ones
+        if (oi->output->mm_height > 0) {
+            float ar = float(oi->output->mm_width) / float(oi->output->mm_height);
+            if (ar >= 1.999f) { // Consider 18:9+ as ultrawide
+                XRRModeInfo *best = nullptr;
+                for (int i = 0; i < oi->output->nmode; ++i) {
+                    if (!_modeMap.contains(oi->output->modes[i]))
+                        continue;
+                    auto mode = _modeMap[oi->output->modes[i]];
+                    if (mode->height == 0)
+                        continue;
+                    float resAr = float(mode->width) / float(mode->height);
+                    if (qAbs(resAr - ar) > 0.02f) // Check if aspect ratios are same
+                        continue;
+                    if (best == nullptr || mode->width > best->width) {
+                        best = mode; // If multiple resolutions match, use the largest one
+                    }
+                }
+                if (best != nullptr)
+                    return best; // Ultrawide it is!
+            }
+        }
+        // "Normal" way of determining optimal resolution
         if (oi->output->npreferred > 0) {
                 mode = oi->output->modes[0];
         } else {
+            // No preferred one, try some more or less clever fallback
                 mode = None;
                 if (fallback != nullptr) {
                         mode = getOutputModeForResolution(oi->output, fallback->width, fallback->height);