toplevelexport: fix transformed origin for shm buffers (#9343)

* toplevelexport: fix transformed origin for shm buffers

* toplevelexport: fix style nits

1 files changed, 24 insertions, 1 deletions

diff --git a/src/protocols/ToplevelExport.cpp b/src/protocols/ToplevelExport.cpp
index 8b835b50..a9009aa4 100644
--- a/src/protocols/ToplevelExport.cpp
+++ b/src/protocols/ToplevelExport.cpp
@@ -11,6 +11,7 @@
 #include "../render/Renderer.hpp"
 
 #include <algorithm>
+#include <hyprutils/math/Vector2D.hpp>
 
 CToplevelExportClient::CToplevelExportClient(SP<CHyprlandToplevelExportManagerV1> resource_) : resource(resource_) {
     if UNLIKELY (!good())
@@ -289,7 +290,29 @@ bool CToplevelExportFrame::copyShm(timespec* now) {
     glPixelStorei(GL_PACK_ALIGNMENT, 1);
 
     auto glFormat = PFORMAT->flipRB ? GL_BGRA_EXT : GL_RGBA;
-    glReadPixels(0, 0, box.width, box.height, glFormat, PFORMAT->glType, pixelData);
+
+    auto origin = Vector2D(0, 0);
+    switch (PMONITOR->transform) {
+        case WL_OUTPUT_TRANSFORM_FLIPPED_180:
+        case WL_OUTPUT_TRANSFORM_90: {
+            origin.y = PMONITOR->vecPixelSize.y - box.height;
+            break;
+        }
+        case WL_OUTPUT_TRANSFORM_FLIPPED_270:
+        case WL_OUTPUT_TRANSFORM_180: {
+            origin.x = PMONITOR->vecPixelSize.x - box.width;
+            origin.y = PMONITOR->vecPixelSize.y - box.height;
+            break;
+        }
+        case WL_OUTPUT_TRANSFORM_FLIPPED:
+        case WL_OUTPUT_TRANSFORM_270: {
+            origin.x = PMONITOR->vecPixelSize.x - box.width;
+            break;
+        }
+        default: break;
+    }
+
+    glReadPixels(origin.x, origin.y, box.width, box.height, glFormat, PFORMAT->glType, pixelData);
 
     if (overlayCursor) {
         g_pPointerManager->unlockSoftwareForMonitor(PMONITOR->self.lock());