From 0defaefdba7c7e747191445dc5ef0e5256b54d60 Mon Sep 17 00:00:00 2001
From: Casey <67843601+caseyjoy@users.noreply.github.com>
Date: Thu, 15 Jun 2023 02:29:39 -0600
Subject: [PATCH] Update GridMap editor grid location when required

The GridMap editor's grid previously did not not move when moving
the tile cursor, only on certain menu actions.

This commit adds an update_grid call for valid mouse movement in
the editor, changes update_grid to only offset if there's a valid
cursor, and adds updates for the grid and cursor when a mesh library
is changed since we need the new RID for the update_grid check,
and if we remove the mesh library we want to make sure it gets
recentered. As a nice side-effect, it also updates to the new cursor
mesh if you load a new mesh library.

Fixes #57068
---
 modules/gridmap/editor/grid_map_editor_plugin.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/modules/gridmap/editor/grid_map_editor_plugin.cpp b/modules/gridmap/editor/grid_map_editor_plugin.cpp
index 14f7b9b5029a..de04d376a0f6 100644
--- a/modules/gridmap/editor/grid_map_editor_plugin.cpp
+++ b/modules/gridmap/editor/grid_map_editor_plugin.cpp
@@ -704,6 +704,9 @@ EditorPlugin::AfterGUIInput GridMapEditor::forward_spatial_input_event(Camera3D
 	Ref<InputEventMouseMotion> mm = p_event;
 
 	if (mm.is_valid()) {
+		// Update the grid, to check if the grid needs to be moved to a tile cursor.
+		update_grid();
+
 		if (do_input_action(p_camera, mm->get_position(), false)) {
 			return EditorPlugin::AFTER_GUI_INPUT_STOP;
 		}
@@ -951,7 +954,8 @@ void GridMapEditor::update_grid() {
 
 	grid_ofs[edit_axis] = edit_floor[edit_axis] * node->get_cell_size()[edit_axis];
 
-	edit_grid_xform.origin = grid_ofs;
+	// If there's a valid tile cursor, offset the grid, otherwise move it back to the node.
+	edit_grid_xform.origin = cursor_instance.is_valid() ? grid_ofs : Vector3();
 	edit_grid_xform.basis = Basis();
 
 	for (int i = 0; i < 3; i++) {
@@ -1076,6 +1080,9 @@ void GridMapEditor::_notification(int p_what) {
 			Ref<MeshLibrary> cgmt = node->get_mesh_library();
 			if (cgmt.operator->() != last_mesh_library) {
 				update_palette();
+				// Update the cursor and grid in case the library is changed or removed.
+				_update_cursor_instance();
+				update_grid();
 			}
 		} break;