Undo functionality

src/src/game-gui.cc

@@ -3,10 +3,13 @@
 
 #include "game.hh"
 #include "game-message.hh"
+#include "gundo.hh"
+#include "main.hh"
 #include "settings.hh"
 #include "robot.hh"
 #include "object_factory.hh"
 #include "i1o1gate.hh"
+#include "tms/core/wdg.h"
 #include "ui.hh"
 #include "adventure.hh"
 #include "motor.hh"
@@ -691,6 +694,8 @@ game::menu_handle_event(tms::event *ev)
 
                 if (found) {
                     if (o.e) {
+                        undo.checkpoint("Added object");
+
                         entity *e = of::create(o.e->g_id);
                         if (e) {
                             menu_objects[gid_to_menu_pos[e->g_id]].highlighted = true;
@@ -1000,6 +1005,10 @@ game::widget_clicked(principia_wdg *w, uint8_t button_id, int pid)
             }
             return true;
 
+        case GW_UNDO:
+            P.add_action(ACTION_UNDO_RESTORE, 0);
+            return true;
+
         case GW_MODE:
             {
                 switch (G->get_mode()) {
@@ -1613,18 +1622,32 @@ game::init_gui(void)
     this->wdg_layervis->priority = 800;
     this->wdg_layervis->set_tooltip("Toggle layer visibility");
 
+    // TODO griffi-gh: add proper icon for the undo button
+    this->wdg_undo = this->wm->create_widget(
+            this->get_surface(), TMS_WDG_BUTTON,
+            GW_UNDO, AREA_TOP_LEFT,
+            gui_spritesheet::get_sprite(S_UNDO), 0);
+    this->wdg_undo->priority = 700;
+    const char* undo_tooltip =
+        "Undo"
+#ifdef TMS_BACKEND_PC
+        " (Ctrl+Z)"
+#endif
+        ;
+    this->wdg_undo->set_tooltip(undo_tooltip);
+
     this->wdg_mode = this->wm->create_widget(
             this->get_surface(), TMS_WDG_BUTTON,
             GW_MODE, AREA_TOP_LEFT,
             gui_spritesheet::get_sprite(S_CONFIG), 0);
-    this->wdg_mode->priority = 700;
+    this->wdg_mode->priority = 600;
     this->wdg_mode->set_tooltip("Change mode");
 
     this->wdg_advanced = this->wm->create_widget(
             this->get_surface(), TMS_WDG_BUTTON,
             GW_ADVANCED, AREA_TOP_LEFT,
             gui_spritesheet::get_sprite(S_ADVUP), 0);
-    this->wdg_advanced->priority = 600;
+    this->wdg_advanced->priority = 500;
     this->wdg_advanced->set_tooltip("Toggle advanced options");
 
     this->wdg_help = this->wm->create_widget(
@@ -2373,6 +2396,13 @@ game::refresh_widgets()
         }
     }
 
+    // XXX griffi-gh: Is this the right condition?
+    // Shouldn't we always show the undo button in sandbox mode? (even without advanced mode)
+    if (G->state.sandbox && W->is_paused() /*&& G->state.advanced_mode*/) {
+        this->wdg_undo->add();
+        this->wdg_undo->faded = undo.amount() == 0;
+    }
+
     if ((this->state.sandbox || this->state.test_playing || W->is_paused() || W->is_puzzle()) && (W->level.type != LCAT_ADVENTURE || W->is_paused())) {
         this->wdg_playpause->add();
     }

src/src/game.cc

@@ -20,6 +20,7 @@
 #include "gravityman.hh"
 #include "grid.hh"
 #include "group.hh"
+#include "gundo.hh"
 #include "i0o1gate.hh"
 #include "i1o1gate.hh"
 #include "i2o1gate.hh"
@@ -67,6 +68,7 @@
 #include "world.hh"
 #include "player_activator.hh"
 #include "gui.hh"
+#include <cstddef>
 #ifdef DEBUG
 /* for print_screen_point_info */
 #include "terrain.hh"
@@ -7183,6 +7185,37 @@ game::open_sandbox(int id_type, uint32_t id)
     this->refresh_widgets();
 }
 
+void game::open_sandbox_snapshot_mem(const void* snapshot, size_t size) {
+    tms_assertf(this->state.sandbox,
+        "FATAL ERROR. Level is not a sandbox. This is a bug.\n"
+        "open_sandbox_snapshot_mem is only supported while in sandbox mode.\n"
+        "You probably tried to undo while playing a level, which shouldn't be possible");
+
+    W->lb.clear();
+    W->lb.ensure(size);
+    memcpy(W->lb.buf, snapshot, size);
+    W->lb.size = size;
+
+    this->reset();
+    this->state.sandbox = true;
+    W->open_internal(
+        size,
+        W->level_id_type,
+        W->level.local_id,
+        W->is_paused(),
+        true,
+        W->level.save_id,
+        false,
+        true
+    );
+
+    this->apply_level_properties();
+    this->add_entities(&W->all_entities, &W->groups, &W->connections, &W->cables);
+    W->begin();
+
+    this->refresh_widgets();
+}
+
 bool
 game::delete_level(int id_type, uint32_t id, uint32_t save_id)
 {
@@ -7974,6 +8007,14 @@ game::handle_input_paused(tms::event *ev, int action)
             case TMS_KEY_E:
                 if (ev->data.key.mod & TMS_MOD_SHIFT
                         && this->state.sandbox && this->selection.e) {
+                    // Save undo state if any items are going to be modified
+                    for (c_map::iterator it = this->pairs.begin(); it != this->pairs.end(); ++it) {
+                        if (!it->second->typeselect) {
+                            undo.checkpoint("Connect all");
+                            break;
+                        }
+                    }
+
                     entity *saved = this->selection.e;
                     for (c_map::iterator it = this->pairs.begin(); it != this->pairs.end(); ++it) {
                         connection *c = it->second;
@@ -8337,6 +8378,7 @@ game::handle_input_paused(tms::event *ev, int action)
 #endif
                     ) {
                 tms_debugf("IMPORT (%.2f)", dist);
+                undo.checkpoint("Import partial");
                 this->import_object(this->multi.import->lvl_id);
             }
         } else {
@@ -9594,8 +9636,10 @@ game::check_click_conntype(int x, int y)
                     : b2Vec2(pt[this->cs_conn->layer].x, pt[this->cs_conn->layer].y);
 
     if ((p1 - point).Length() < w) {
+        undo.checkpoint("Connection (Fixed)");
         this->apply_connection(this->cs_conn, 0);
     } else if ((p2 - point).Length() < w) {
+        undo.checkpoint("Connection (Rotating)");
         this->apply_connection(this->cs_conn, 1);
     }
 
@@ -9803,6 +9847,8 @@ game::check_click_conn(int x, int y)
                 return true;
             }
 
+            undo.checkpoint("Connection");
+
             if (W->is_adventure() && W->is_playing()) {
                 this->apply_connection(c, c->option);
             } else {

src/src/game.hh

@@ -42,6 +42,7 @@ enum {
     GW_PLAYPAUSE,
     GW_ORTHOGRAPHIC,
     GW_LAYERVIS,
+    GW_UNDO,
     GW_MODE,
     GW_ADVANCED,
     GW_HELP,
@@ -440,6 +441,7 @@ class game : public pscreen
     principia_wdg *wdg_playpause;
     principia_wdg *wdg_orthographic;
     principia_wdg *wdg_layervis;
+    principia_wdg *wdg_undo;
     principia_wdg *wdg_mode;
     principia_wdg *wdg_advanced;
     principia_wdg *wdg_help;
@@ -1105,6 +1107,12 @@ class game : public pscreen
     void open_state(int id_type, uint32_t id, uint32_t save_id);
     void open_sandbox(int id_type, uint32_t id);
     void open_play(int id_type, uint32_t id, pkginfo *pkg, bool test_playing=false, int is_main_puzzle=0);
+    // Reload state of the *currently open* level from an in-memory snapshot.
+    // Shit WILL break in unpredictable ways if:
+    // - save data is compressed
+    // - save data comes from a different level
+    // - the level is not a sandbox level
+    void open_sandbox_snapshot_mem(const void* snapshot, size_t size);
 
     void begin_play(bool has_state=false);
 

src/src/gui.cc

@@ -116,6 +116,7 @@ struct sprite_load_data gui_spritesheet::sprites[NUM_SPRITES] = {
     { "data-shared/textures/ui/btn_ccw.png", &atlas },
     { "data-shared/textures/ui/btn_lock.png", &atlas },
     { "data-shared/textures/ui/btn_unlock.png", &atlas },
+    { "data-shared/textures/ui/btn_undo.png", &atlas },
 
     { "data-shared/textures/menu/menu_play.png", &atlas },
     { "data-shared/textures/menu/menu_create.png", &atlas },

src/src/gui.hh

@@ -92,6 +92,7 @@ enum {
     S_CCW,
     S_BTN_LOCK,
     S_BTN_UNLOCK,
+    S_UNDO,
 
     S_MENU_PLAY,
     S_MENU_CREATE,