OpenXRKneeboard.cpp.diff

diff --git a/src/injectables/OpenXRKneeboard.cpp b/src/injectables/OpenXRKneeboard.cpp
index 0c3f6d51..5cdbb322 100644
--- a/src/injectables/OpenXRKneeboard.cpp
+++ b/src/injectables/OpenXRKneeboard.cpp
@@ -50,6 +50,9 @@
 #include <openxr/openxr_platform.h>
 #include <openxr/openxr_reflection.h>
 
+// From OpenXR v1.1 SDK for XrPosef_Multiply
+#include "xr_linear.h"
+
 namespace OpenKneeboard {
 
 namespace {
@@ -109,9 +112,7 @@ static inline std::string_view xrresult_to_string(XrResult code) {
   switch (code) {
 #define XR_RESULT_CASE(enum_name, value) \
   case enum_name: \
-    return { \
-      #enum_name \
-    }; \
+    return {#enum_name}; \
     XR_LIST_ENUM_XrResult(XR_RESULT_CASE)
 #undef XR_RESULT_CASE
     default:
@@ -370,18 +371,26 @@ XrResult OpenXRKneeboard::xrEndFrame(
       SHM::SHARED_TEXTURE_IS_PREMULTIPLIED,
       "Use premultiplied alpha in shared texture, or pass "
       "XR_COMPOSITION_LAYER_UNPREMULTIPLIED_ALPHA_BIT");
+
+    XrSpaceLocation localInView {XR_TYPE_SPACE_LOCATION};
+    OPENKNEEBOARD_ALWAYS_ASSERT(XR_SUCCEEDED(gNext->xrLocateSpace(
+      mLocalSpace, mViewSpace, frameEndInfo->displayTime, &localInView)));
+    const auto kneeboardInLocal = this->GetXrPosef(params.mKneeboardPose);
+    XrPosef kneeboardInView {};
+    XrPosef_Multiply(&kneeboardInView, &localInView.pose, &kneeboardInLocal);
+
     addedXRLayers.push_back({
       .type = XR_TYPE_COMPOSITION_LAYER_QUAD,
       .next = nullptr,
       .layerFlags = XR_COMPOSITION_LAYER_BLEND_TEXTURE_SOURCE_ALPHA_BIT,
-      .space = mLocalSpace,
+      .space = mViewSpace,
       .eyeVisibility = XR_EYE_VISIBILITY_BOTH,
       .subImage = XrSwapchainSubImage {
         .swapchain = mSwapchain,
         .imageRect = destRect.StaticCast<int, XrRect2Di>(),
         .imageArrayIndex = 0,
       },
-      .pose = this->GetXrPosef(params.mKneeboardPose),
+      .pose = kneeboardInView,
       .size = { params.mKneeboardSize.x, params.mKneeboardSize.y },
     });