Disengage frame render during output transitionskc/output-crash-1

1 files changed, 15 insertions, 0 deletions

diff --git a/src/gui/sdlmain.cpp b/src/gui/sdlmain.cpp
index 5ea0bcc95..8b5284c7f 100644
--- a/src/gui/sdlmain.cpp
+++ b/src/gui/sdlmain.cpp
@@ -610,6 +610,14 @@ void GFX_ForceFullscreenExit()
 	return log;
 }
 
+// Let the presentation layer safely call no-op functions.
+// Useful during output initialization or transitions.
+static void disengage_frame_rendering()
+{
+	sdl.frame.update = update_frame_noop;
+	sdl.frame.present = present_frame_noop;
+}
+
 // This is a hack to prevent SDL2 from re-creating window internally. Prevents
 // crashes on Windows and Linux, and prevents initial window from being visibly
 // destroyed (for window managers that show animations while creating window,
@@ -1490,6 +1498,10 @@ Bitu GFX_SetSize(int width,
 	if (sdl.updating)
 		GFX_EndUpdate(nullptr);
 
+	disengage_frame_rendering();
+	// The rendering objects are recreated below with new sizes, after which
+	// frame rendering is re-engaged with the output-type specific calls.
+
 	const bool double_width = flags & GFX_DBL_W;
 	const bool double_height = flags & GFX_DBL_H;
 
@@ -3039,6 +3051,9 @@ static void set_output(Section *sec, bool should_stretch_pixels)
 	const auto section = static_cast<const Section_prop *>(sec);
 	std::string output = section->Get_string("output");
 
+	disengage_frame_rendering();
+	// it's the job of everything after this to re-engage it.
+
 	if (output == "surface") {
 		sdl.desktop.want_type = SCREEN_SURFACE;
 	} else if (output == "texture") {