Workaround SteamVR-for-Linux issue 421

ValveSoftware/SteamVR-for-Linux#421

src/openxr/OpenXRApi.cpp

@@ -1909,6 +1909,12 @@ void OpenXRApi::render_openxr(int eye, uint32_t texid, bool has_external_texture
 			return;
 		}
 	}
+
+#ifdef __linux__
+	// TODO: should not be necessary, but is for SteamVR 1.16.4 (but not 1.15.x)
+	glXMakeCurrent(graphics_binding_gl.xDisplay, graphics_binding_gl.glxDrawable,
+				   graphics_binding_gl.glxContext);
+#endif
 }
 
 void OpenXRApi::fill_projection_matrix(int eye, godot_real p_z_near, godot_real p_z_far, godot_real *p_projection) {
@@ -2273,6 +2279,12 @@ int OpenXRApi::get_external_texture_for_eye(int eye, bool *has_support) {
 		return 0;
 	}
 
+#ifdef __linux__
+	// TODO: should not be necessary, but is for SteamVR 1.16.4 (but not 1.15.x)
+	glXMakeCurrent(graphics_binding_gl.xDisplay, graphics_binding_gl.glxDrawable,
+				   graphics_binding_gl.glxContext);
+#endif
+
 	// process should be called by now but just in case...
 	if (state > XR_SESSION_STATE_UNKNOWN && buffer_index != NULL) {
 		// make sure we know that we're rendering directly to our
@@ -2499,6 +2511,12 @@ void OpenXRApi::process_openxr() {
 		// TODO: Tell godot not do render VR to save resources.
 		// See render_openxr() for the corresponding early exit.
 	}
+
+#ifdef __linux__
+	// TODO: should not be necessary, but is for SteamVR 1.16.4 (but not 1.15.x)
+	glXMakeCurrent(graphics_binding_gl.xDisplay, graphics_binding_gl.glxDrawable,
+				   graphics_binding_gl.glxContext);
+#endif
 }
 
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