Fixes #1031 - Show structure collapse warning when deploying and moving.

megamek/i18n/megamek/client/messages.properties

@@ -1097,6 +1097,8 @@ CommonMenuBar.viewToggleSensorRange=Visual & Sensor Ranges
 CommonMenuBar.viewToggleSensorRangeToolTip=Outline Visual & Sensor Ranges
 CommonMenuBar.viewToggleFiringSolutions=Firing Solutions
 CommonMenuBar.viewToggleFiringSolutionsToolTip=During the firing phase, to-hit modifiers for each range bracket will be drawn on units
+CommonMenuBar.viewToggleCFWarning=Structure Collapse Warning
+CommonMenuBar.viewToggleCFWarningToolTip=Show buildings or bridges that could collapse if entered by selected unit
 CommonMenuBar.viewChangeTheme=Change Tileset Theme
 CommonMenuBar.viewResetWindowPos=Reset Window Positions
 CommonMenuBar.moveLAMmechMode=Transform to mek mode

megamek/src/megamek/client/ui/swing/ClientGUI.java

@@ -162,6 +162,7 @@ public class ClientGUI extends JPanel implements BoardViewListener,
     public static final String VIEW_TOGGLE_FOV_DARKEN = "viewToggleFovDarken";
     public static final String VIEW_TOGGLE_FOV_HIGHLIGHT = "viewToggleFovHighlight";
     public static final String VIEW_TOGGLE_FIRING_SOLUTIONS = "viewToggleFiringSolutions";
+    public static final String VIEW_TOGGLE_CF_WARNING = "viewToggleCFWarnings";
     public static final String VIEW_MOVE_ENV = "viewMovementEnvelope";
     public static final String VIEW_TURN_DETAILS_OVERLAY = "viewTurnDetailsOverlay";
     public static final String VIEW_MOVE_MOD_ENV = "viewMovModEnvelope";
@@ -934,6 +935,9 @@ public void actionPerformed(ActionEvent event) {
                 }
                 bv.refreshDisplayables();
                 break;
+            case VIEW_TOGGLE_CF_WARNING:
+                ConstructionFactorWarning.handleActionPerformed();
+                break;
             case VIEW_MOVE_ENV:
                 if (curPanel instanceof MovementDisplay) {
                     GUIP.setMoveEnvelope(!GUIP.getMoveEnvelope());

megamek/src/megamek/client/ui/swing/CommonMenuBar.java

@@ -121,6 +121,7 @@ public class CommonMenuBar extends JMenuBar implements ActionListener, IPreferen
     private JCheckBoxMenuItem toggleFovHighlight = new JCheckBoxMenuItem(getString("CommonMenuBar.viewToggleFovHighlight"));
     private JCheckBoxMenuItem toggleFovDarken = new JCheckBoxMenuItem(getString("CommonMenuBar.viewToggleFovDarken"));
     private JCheckBoxMenuItem toggleFiringSolutions = new JCheckBoxMenuItem(getString("CommonMenuBar.viewToggleFiringSolutions"));
+    private JCheckBoxMenuItem toggleCFWarning = new JCheckBoxMenuItem(getString("CommonMenuBar.viewToggleCFWarning"));
     private JCheckBoxMenuItem viewMovementEnvelope = new JCheckBoxMenuItem(getString("CommonMenuBar.movementEnvelope"));
     private JCheckBoxMenuItem viewTurnDetailsOverlay  = new JCheckBoxMenuItem(getString("CommonMenuBar.turnDetailsOverlay"));
     private JMenuItem viewMovModEnvelope = new JMenuItem(getString("CommonMenuBar.movementModEnvelope"));
@@ -305,6 +306,10 @@ public CommonMenuBar() {
         toggleFiringSolutions.setToolTipText(Messages.getString("CommonMenuBar.viewToggleFiringSolutionsToolTip"));
         toggleFiringSolutions.setSelected(GUIP.getFiringSolutions());
 
+        initMenuItem(toggleCFWarning, menu, VIEW_TOGGLE_CF_WARNING);
+        toggleCFWarning.setToolTipText(Messages.getString("CommonMenuBar.viewToggleCFWarningToolTip"));
+        toggleCFWarning.setSelected(GUIP.getShowCFWarnings());
+
         /* TODO: moveTraitor = createMenuItem(menu, getString("CommonMenuBar.moveTraitor"), MovementDisplay.MOVE_TRAITOR);  */
 
         // Create the Help menu
@@ -479,6 +484,7 @@ private synchronized void updateEnabledStates() {
         toggleFovHighlight.setEnabled(isInGameBoardView);
         toggleFovDarken.setEnabled(isInGameBoardView);
         toggleFiringSolutions.setEnabled(isInGameBoardView);
+        toggleCFWarning.setEnabled(isInGameBoardView);
         viewMovementEnvelope.setEnabled(isInGameBoardView);
         viewTurnDetailsOverlay.setEnabled(isInGameBoardView);
         viewMovModEnvelope.setEnabled(isInGameBoardView);

megamek/src/megamek/client/ui/swing/ConstructionFactorWarning.java

@@ -0,0 +1,203 @@
+/*
+ * Copyright (c) 2023 - The MegaMek Team. All Rights Reserved.
+ *
+ * This file is part of MegaMek.
+ *
+ * MegaMek is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * MegaMek is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with MegaMek. If not, see <http://www.gnu.org/licenses/>.
+ */
+package megamek.client.ui.swing;
+
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.List;
+
+import org.apache.logging.log4j.LogManager;
+
+import megamek.common.Board;
+import megamek.common.Building;
+import megamek.common.Coords;
+import megamek.common.Entity;
+import megamek.common.Game;
+import megamek.common.enums.GamePhase;
+
+/**
+ * Construction Factor Warning Logic.  Handles events, help
+ * methods and logic related to CF Warning in a way that
+ * can be unit tested and encapsulated from BoardView and
+ * ClientGUI and other actors.
+ */
+public class ConstructionFactorWarning {
+    /*
+     * Handler for ClientGUI actionPerformed event. Encapsulates
+     * as much Construction Factory Warning logic possible.
+     */
+    public static void handleActionPerformed() {
+        toggleCFWarning();
+    }
+
+    /*
+     * Return true if the passed in phase is a phase that should allow
+     * Construction Factor Warnings such as Deploy and Movement.
+     */
+    public static boolean isCFWarningPhase(GamePhase gp) {
+        return (gp == GamePhase.DEPLOYMENT || gp == GamePhase.MOVEMENT);
+    }
+
+    public static boolean shouldShow(GamePhase gp) {
+        return shouldShow(gp, true);
+    }
+
+    /*
+     * Returns true if the show construction factor warning preference
+     * is enabled and in a phase that should show warnings.
+     */
+    public static boolean shouldShow(GamePhase gp, boolean isEnabled) {
+        return (isEnabled && isCFWarningPhase(gp));
+    }
+
+    private static boolean toggleCFWarning() {
+        //Toggle the GUI Preference setting for CF Warning setting.
+        GUIPreferences GUIP = GUIPreferences.getInstance();
+        GUIP.setShowCFWarnings(!GUIP.getShowCFWarnings());
+        return (GUIP.getShowCFWarnings());
+    }
+
+    /**
+     * For the provided entity, find all hexes within movement range with
+     * buildings that would collapse if entered or landed upon.  This is
+     * used by the {@link MovementDisplay} class.
+     *
+     * @param g {@link Game} provided by the phase display class
+     * @param e {@link Entity} currently selected in the movement phase.
+     * @param b {@link Board} board object with building data.
+     *
+     * @return returns a list of {@link Coords} that where warning flags
+     * 		should be placed.
+     */
+    public static List<Coords> findCFWarningsMovement(Game g, Entity e, Board b) {
+        List<Coords> warnList = new ArrayList<Coords>();
+
+        try {
+            //Only calculate CF Warnings for entity types in the whitelist.
+            if (!entityTypeIsInWhiteList(e)) {
+                return warnList;
+            }
+
+            Coords pos = e.getPosition();
+            int range = Math.max(e.getJumpMP(), e.getRunMP());
+
+            List<Coords> hexesToCheck = new ArrayList<Coords>();
+            if (pos != null) {
+                hexesToCheck = pos.allAtDistanceOrLess(range + 1);
+            } else {
+                return hexesToCheck;
+            }
+
+            // For each hex in jumping range, look for buildings, if found check for collapse.
+            for (Coords c : hexesToCheck) {
+                //is there a building at this location?  If so add it to hexes with buildings.
+                Building bld = b.getBuildingAt(c);
+
+                // If a building, compare total weight and add to warning list.
+                if (null != bld) {
+                    if (calculateTotalTonnage(g, e, c) > bld.getCurrentCF(c)) {
+                        warnList.add(c);
+                    }
+                }
+            }
+        } catch (Exception exc) {
+            // Something bad is going to happen.  This is a passive feature return an empty list.
+            LogManager.getLogger().error("Unable to calculate construction factor collapse candidates. (Movement)");
+            return new ArrayList<Coords>();
+        }
+
+        return warnList;
+    }
+
+    /*
+     *  Returns true if the selected entity should have CF warnings calculated when selected.
+     */
+    protected static boolean entityTypeIsInWhiteList(Entity e) {
+        // Include entities that are ground units and onboard only.  Flying units need not apply.
+        return (e.isGround() && !e.isOffBoard());
+    }
+
+    /**
+     * Looks for all building locations in a legal deploy zone that would collapse
+     * if the currently selected entity would deploy there.  This is used by
+     * {@link DeploymentDisplay} to render a warning sprite on danger hexes.
+     *
+     * @param g {@link Game} provided by the phase display class
+     * @param e {@link Entity} currently selected in the movement phase.
+     * @param b {@link Board} board object with building data.
+     *
+     * @return returns a list of {@link Coords} that where warning flags
+     * 		should be placed.
+     */
+    public static List<Coords> findCFWarningsDeployment(Game g, Entity e, Board b) {
+	List<Coords> warnList = new ArrayList<Coords>();
+
+        try {
+            //Only calculate CF Warnings for entity types in the whitelist.
+            if (!entityTypeIsInWhiteList(e)) {
+                return warnList;
+            }
+
+            Enumeration<Building> buildings = b.getBuildings();
+
+            // Enumerate through all the buildings
+            while (buildings.hasMoreElements()) {
+                Building bld = buildings.nextElement();
+                List<Coords> buildingList = bld.getCoordsList();
+
+                // For each hex occupied by the building, check if it's a legal deploy hex.
+                for (Coords c : buildingList) {
+                    if (b.isLegalDeployment(c, e)) {
+                        // Check for weight limits for collapse and add a warning sprite.
+                        if (calculateTotalTonnage(g, e, c) > bld.getCurrentCF(c)) {
+                            warnList.add(c);
+                        }
+                    }
+                }
+            }
+        } catch (Exception exc) {
+            // Something bad is going to happen.  This is a passive feature return an empty list.
+            LogManager.getLogger().error("Unable to calculate construction factor collapse candidates. (Deployment)");
+            return new ArrayList<Coords>();
+        }
+
+        return warnList;
+    }
+
+    /*
+     *  Determine the total weight burden for a building hex at a location.
+     *  This includes the entity current weight summed with any unit weights
+     *  at the hex location that could cause a building to collapse.
+     */
+    protected static double calculateTotalTonnage(Game g, Entity selected, Coords c) {
+        // Calculate total weight of entity and all entities at the location.
+        double totalWeight = selected.getWeight();
+        List<Entity> units = g.getEntitiesVector(c, true);
+        for (Entity ent : units) {
+            if (ConstructionFactorWarning.isEntityPartOfWeight(selected, ent)) {
+                totalWeight += ent.getWeight();
+            }
+        }
+        return totalWeight;
+    }
+
+    protected static boolean isEntityPartOfWeight(Entity selected, Entity inHex) {
+        return ((selected != inHex) && inHex.isGround() && !inHex.isAirborneVTOLorWIGE());
+    }
+}

megamek/src/megamek/client/ui/swing/DeploymentDisplay.java

@@ -231,6 +231,7 @@ public void selectEntity(int en) {
             clientgui.getUnitDisplay().showPanel("movement");
             clientgui.getBoardView().setWeaponFieldOfFire(ce().getFacing(), ce().getPosition());
             clientgui.getBoardView().setSensorRange(ce(), ce().getPosition());
+            computeCFWarningHexes(ce());
         } else {
             disableButtons();
             setNextEnabled(true);
@@ -239,6 +240,17 @@ public void selectEntity(int en) {
         }
     }
 
+    private void computeCFWarningHexes(Entity ce) {
+        List<Coords> warnList =
+                ConstructionFactorWarning.findCFWarningsDeployment(
+                        clientgui.getBoardView().game,
+                        ce,
+                        clientgui.getBoardView().game.getBoard());
+
+        clientgui.getBoardView().setCFWarningSprites(warnList);
+
+    }
+
     /** Enables relevant buttons and sets up for your turn. */
     private void beginMyTurn() {
         clientgui.maybeShowUnitDisplay();

megamek/src/megamek/client/ui/swing/GUIPreferences.java

@@ -203,6 +203,7 @@ public class GUIPreferences extends PreferenceStoreProxy {
     public static final String TEAM_COLORING = "EntityTeamLabelColor";
     public static final String FOCUS = "Focus";
     public static final String FIRING_SOLUTIONS = "FiringSolutions";
+    public static final String CONSTRUCTOR_FACTOR_WARNING = "ConstructionFactorWarning";
     public static final String MOVE_ENVELOPE = "MoveEnvelope";
     public static final String TURN_DETAILS_OVERLAY = "TurnDetailsOverlay";
     public static final String FOV_HIGHLIGHT = "FovHighlight";
@@ -602,6 +603,7 @@ protected GUIPreferences() {
         store.setDefault(UNIT_LABEL_BORDER, true);
         store.setDefault(UNIT_LABEL_STYLE, LabelDisplayStyle.NICKNAME.name());
         store.setDefault(FIRING_SOLUTIONS, true);
+        store.setDefault(CONSTRUCTOR_FACTOR_WARNING, true);
         store.setDefault(GUI_SCALE, 1);
         store.setDefault(LOBBY_MEKTABLE_UNIT_WIDTH, 170);
         store.setDefault(LOBBY_MEKTABLE_PILOT_WIDTH, 80);
@@ -1003,6 +1005,10 @@ public boolean getFiringSolutions() {
         return store.getBoolean(FIRING_SOLUTIONS);
     }
 
+    public boolean getShowCFWarnings() {
+        return store.getBoolean(CONSTRUCTOR_FACTOR_WARNING);
+    }
+
     public boolean getMoveEnvelope() {
         return store.getBoolean(MOVE_ENVELOPE);
     }
@@ -1783,6 +1789,10 @@ public void setFiringSolutions(boolean state) {
         store.setValue(FIRING_SOLUTIONS, state);
     }
 
+    public void setShowCFWarnings(boolean b) {
+        store.setValue(CONSTRUCTOR_FACTOR_WARNING, b);
+    }
+
     public void setMoveEnvelope(boolean state) {
         store.setValue(MOVE_ENVELOPE, state);
     }
@@ -3141,4 +3151,4 @@ protected Color parseRGB(String text) {
         return Color.BLUE;
     }
     //endregion Colours
-}
+}

megamek/src/megamek/client/ui/swing/MovementDisplay.java

@@ -781,6 +781,7 @@ public synchronized void selectEntity(int en) {
         }
         clientgui.getBoardView().clearFieldOfFire();
         computeMovementEnvelope(ce);
+        computeCFWarningHexes(ce);
     }
 
     private MegamekButton getBtn(MoveCommand c) {
@@ -4544,6 +4545,16 @@ && ce().getMovementMode() == EntityMovementMode.TRACKED) {
         clientgui.getBoardView().setMovementModifierEnvelope(lpf.getLongestComputedPaths());
     }
 
+    private void computeCFWarningHexes(Entity ce) {
+        List<Coords> warnList =
+                ConstructionFactorWarning.findCFWarningsMovement(
+                        clientgui.getBoardView().game,
+                        ce,
+                        clientgui.getBoardView().game.getBoard());
+
+        clientgui.getBoardView().setCFWarningSprites(warnList);
+    }
+
     //
     // ActionListener
     //