OpenCanopy: Prevent cut-off entries entirely

Changelog.md

@@ -12,6 +12,7 @@ OpenCore Changelog
 - Fixed creating log file when root file system is not writable
 - Fixed `DisableSingleUser` not being enabled in certain cases
 - Added `ForceBooterSignature` quirk for Mac EFI firmware
+- Fixed OpenCanopy sometimes cutting off shown boot entries
 
 #### v0.6.7
 - Fixed ocvalidate return code to be non-zero when issues are found

Platform/OpenCanopy/GuiApp.h

@@ -103,6 +103,11 @@ BootPickerViewInitialize (
   IN  GUI_CURSOR_GET_IMAGE     GetCursorImage
   );
 
+VOID
+BootPickerViewLateInitialize (
+  VOID
+  );
+
 EFI_STATUS
 BootPickerEntriesAdd (
   IN OC_PICKER_CONTEXT              *Context,

Platform/OpenCanopy/OcBootstrap.c

@@ -130,6 +130,8 @@ OcShowMenuByOc (
     }
   }
 
+  BootPickerViewLateInitialize ();
+
   GuiRedrawAndFlushScreen (&mDrawContext);
 
   if (BootContext->PickerContext->PickerAudioAssist) {

Platform/OpenCanopy/Views/BootPicker.c

@@ -272,30 +272,20 @@ InternalBootPickerSelectEntry (
 
 INT64
 InternelBootPickerScrollSelected (
-  IN UINT32  Scale
+  VOID
   )
 {
   CONST GUI_VOLUME_ENTRY *SelectedEntry;
   INT64                  EntryOffsetX;
 
-  ASSERT (mBootPicker.SelectedEntry != NULL);
+  if (mBootPicker.SelectedEntry == NULL) {
+    return 0;
+  }
   //
   // If the selected entry is outside of the view, scroll it accordingly.
-  // This function is called every time an entry is added or changed by the
-  // user. Due to this internal design, the selected entry can never be outside
-  // of the view by more than one entry's size.
   //
   SelectedEntry = mBootPicker.SelectedEntry;
   EntryOffsetX  = mBootPicker.Hdr.Obj.OffsetX + SelectedEntry->Hdr.Obj.OffsetX;
-  //
-  // If the selected element is off-screen, scroll the view such that it is at
-  // the very edge of the view. As the view's width bounds precisely a set of
-  // boot entries (i.e. there can never be a partial entry or extra padding),
-  // this is equivalent to scrolling one boot entry spot.
-  // This is done to achieve the correct offset during initialisation as the
-  // entries may be at "half-steps" due to centering.
-  //
-  ASSERT ((mBootPickerContainer.Obj.Width + BOOT_ENTRY_SPACE * Scale) % ((BOOT_ENTRY_WIDTH + BOOT_ENTRY_SPACE) * Scale) == 0);
 
   if (EntryOffsetX < 0) {
     return -EntryOffsetX;
@@ -385,7 +375,7 @@ InternalBootPickerChangeEntry (
   PrevEntry = This->SelectedEntry;
   InternalBootPickerSelectEntry (This, DrawContext, NewEntry);
 
-  ScrollOffset = InternelBootPickerScrollSelected (DrawContext->Scale);
+  ScrollOffset = InternelBootPickerScrollSelected ();
   if (ScrollOffset == 0) {
     //
     // To redraw the entry *and* the selector, draw the entire height of the
@@ -1233,7 +1223,6 @@ BootPickerEntriesAdd (
   BOOLEAN                     UseDiskLabel;
   BOOLEAN                     UseGenericLabel;
   BOOLEAN                     Result;
-  INT64                       ScrollOffset;
 
   ASSERT (GuiContext != NULL);
   ASSERT (Entry != NULL);
@@ -1447,11 +1436,6 @@ BootPickerEntriesAdd (
     GuiContext->BootEntry = Entry;
   }
 
-  if (mBootPicker.SelectedEntry != NULL) {
-    ScrollOffset = InternelBootPickerScrollSelected (GuiContext->Scale);
-    mBootPicker.Hdr.Obj.OffsetX += ScrollOffset;
-  }
-
   return EFI_SUCCESS;
 }
 
@@ -1704,6 +1688,55 @@ BootPickerViewInitialize (
   return EFI_SUCCESS;
 }
 
+VOID
+BootPickerViewLateInitialize (
+  VOID
+  )
+{
+  INT64                  ScrollOffset;
+  CONST LIST_ENTRY       *ListEntry;
+  CONST GUI_VOLUME_ENTRY *BootEntry;
+  INT64                  FirstPosOffset;
+
+  ASSERT (mBootPicker.SelectedEntry != NULL);
+
+  ScrollOffset = InternelBootPickerScrollSelected ();
+  //
+  // If ScrollOffset is non-0, the selected entry will be aligned left- or
+  // right-most. The view holds a discrete amount of entries, so cut-offs are
+  // impossible.
+  //
+  if (ScrollOffset == 0) {
+    ListEntry = mBootPicker.Hdr.Obj.Children.BackLink;
+    ASSERT (ListEntry == &mBootPickerSelector.Hdr.Link);
+
+    FirstPosOffset = 0;
+    //
+    // Last entry is always the selector.
+    //
+    ListEntry = ListEntry->BackLink;
+    //
+    // Find the first entry that is fully visible.
+    //
+    while (!IsNull (&mBootPicker.Hdr.Obj.Children, ListEntry)) {
+      BootEntry = BASE_CR (ListEntry, GUI_VOLUME_ENTRY, Hdr.Link);
+      if (mBootPicker.Hdr.Obj.OffsetX + BootEntry->Hdr.Obj.OffsetX < 0) {
+        break;
+      }
+
+      FirstPosOffset = mBootPicker.Hdr.Obj.OffsetX + BootEntry->Hdr.Obj.OffsetX;
+      ListEntry = ListEntry->BackLink;
+    }
+    //
+    // Move the first fully visible boot entry to the very left to prevent
+    // cut-off entries.
+    //
+    ScrollOffset = -(INT64) FirstPosOffset;
+  }
+
+  mBootPicker.Hdr.Obj.OffsetX += ScrollOffset;
+}
+
 VOID
 BootPickerViewDeinitialize (
   IN OUT GUI_DRAWING_CONTEXT      *DrawContext,