SCI: Add workaround for restoring kq6 saved games (lowres/hires)

KQ6 CD sets a global depending on lowres/hires state right at the
start and some scripts are using it instead of calling kPlatform.
This causes some graphics to be incorrect (well lowres)
in case the user saves in lowres mode, then switches to hires
mode and restores the previously saved game.
We now set that global directly after restoring saved games,
so that this issue does not happen anymore.
KQ6 CD demo did the same.

1 files changed, 20 insertions, 0 deletions

diff --git a/engines/sci/engine/savegame.cpp b/engines/sci/engine/savegame.cpp
index ae7ab431f8..fcb65157d8 100644
--- a/engines/sci/engine/savegame.cpp
+++ b/engines/sci/engine/savegame.cpp
@@ -1012,6 +1012,26 @@ void gamestate_afterRestoreFixUp(EngineState *s, int savegameId) {
 		g_sci->_gfxMenu->kernelSetAttribute(1025 >> 8, 1025 & 0xFF, SCI_MENU_ATTRIBUTE_ENABLED, TRUE_REG);  // Status -> Statistics
 		g_sci->_gfxMenu->kernelSetAttribute(1026 >> 8, 1026 & 0xFF, SCI_MENU_ATTRIBUTE_ENABLED, TRUE_REG);  // Status -> Goals
 		break;
+	case GID_KQ6:
+		if (g_sci->isCD()) {
+			// WORKAROUND:
+			// For the CD version of King's Quest 6, set global depending on current hires/lowres state
+			// The game sets a global at the start depending on it and some things check that global
+			// instead of checking platform like for example the game action menu.
+			// This never happened in the original interpreter, because the original DOS interpreter
+			// was only capable of lowres graphics and the original Windows 3.11 interpreter was only capable
+			// of hires graphics. Saved games were not compatible between those two.
+			// Which means saving during lowres mode, then going into hires mode and restoring that saved game,
+			// will result in some graphics being incorrect (lowres).
+			// That's why we are setting the global after restoring a saved game depending on hires/lowres state.
+			// The CD demo of KQ6 does the same and uses the exact same global.
+			if ((g_sci->getPlatform() == Common::kPlatformWindows) || (g_sci->forceHiresGraphics())) {
+				s->variables[VAR_GLOBAL][0xA9].setOffset(1);
+			} else {
+				s->variables[VAR_GLOBAL][0xA9].setOffset(0);
+			}
+		}
+		break;
 	case GID_PQ2:
 		// HACK: Same as above - enable the save game menu option when loading in PQ2 (bug #6875).
 		// It gets disabled in the game's death screen.