add debug draw mode for balancing target

src/balancing/ArenaView.cpp

@@ -4,11 +4,13 @@
 #include <cmath>
 #include <optional>
 
+#include <QKeyEvent>
 #include <QMouseEvent>
 #include <QPainter>
 #include <QPoint>
 
 #include "ArenaSimulation.h"
+#include "AttackBehavior.h"
 #include "Building.h"
 #include "BuildingSystem.h"
 #include "EntityHitTest.h"
@@ -20,6 +22,7 @@
 #include "HealthComponent.h"
 #include "PositionComponent.h"
 #include "ScrapSystem.h"
+#include "SensorRangeComponent.h"
 #include "ShipIdentityComponent.h"
 #include "StationBodyComponent.h"
 
@@ -38,6 +41,7 @@ ArenaView::ArenaView(ArenaSimulation* sim, const VisualsConfig* visuals,
     , m_prevNonZeroSpeed(1.0)
     , m_rng(std::random_device{}())
     , m_finishedEmitted(false)
+    , m_debugDraw(false)
 {
     setFocusPolicy(Qt::StrongFocus);
 
@@ -167,6 +171,11 @@ void ArenaView::paintGL()
     drawBuildings(painter);
     drawStations(painter);
     drawScrap(painter);
+    if (m_debugDraw)
+    {
+        drawDebugSensorRanges(painter);
+        drawDebugTargetLines(painter);
+    }
     drawShips(painter);
     drawBeams(painter);
 }
@@ -249,6 +258,16 @@ void ArenaView::mousePressEvent(QMouseEvent* event)
     QOpenGLWidget::mousePressEvent(event);
 }
 
+void ArenaView::keyPressEvent(QKeyEvent* event)
+{
+    if (event->key() == Qt::Key_M)
+    {
+        m_debugDraw = !m_debugDraw;
+        return;
+    }
+    QOpenGLWidget::keyPressEvent(event);
+}
+
 // ---------------------------------------------------------------------------
 // Rendering
 // ---------------------------------------------------------------------------
@@ -418,6 +437,55 @@ void ArenaView::drawShips(QPainter& painter)
         });
 }
 
+void ArenaView::drawDebugSensorRanges(QPainter& painter)
+{
+    painter.setBrush(Qt::NoBrush);
+    m_sim->admin().forEach<ShipIdentityComponent, PositionComponent, SensorRangeComponent>(
+        [&](entt::entity /*e*/, const ShipIdentityComponent& si,
+            const PositionComponent& pos, const SensorRangeComponent& sensor)
+        {
+            const std::map<std::string, ShipVisuals>::const_iterator it =
+                m_visuals->ships.find(si.schematicId);
+            if (it == m_visuals->ships.end()) { return; }
+
+            const QPointF center   = worldToWidget(pos.value);
+            const qreal   radiusPx = static_cast<qreal>(sensor.value_tiles)
+                                     * static_cast<qreal>(tilePx());
+            painter.setPen(QPen(it->second.outline, 1));
+            painter.drawEllipse(center, radiusPx, radiusPx);
+        });
+}
+
+void ArenaView::drawDebugTargetLines(QPainter& painter)
+{
+    m_sim->admin().forEach<ShipIdentityComponent, PositionComponent,
+                           FactionComponent, AttackBehavior>(
+        [&](entt::entity /*e*/, const ShipIdentityComponent& /*si*/,
+            const PositionComponent& pos, const FactionComponent& fac,
+            const AttackBehavior& attack)
+        {
+            if (!attack.currentTarget.has_value()) { return; }
+
+            const std::optional<QVector2D> targetPos =
+                entityPosition(*attack.currentTarget);
+            if (!targetPos.has_value()) { return; }
+
+            // Color the line by the ship's team, matching the per-side HQ/station
+            // colors used elsewhere in the arena (team 1 player, team 2 enemy).
+            const BuildingType visType = fac.isEnemy
+                ? BuildingType::EnemyDefenceStation
+                : BuildingType::PlayerDefenceStation;
+            const std::map<BuildingType, BuildingVisuals>::const_iterator it =
+                m_visuals->buildings.find(visType);
+            if (it == m_visuals->buildings.end()) { return; }
+
+            QColor lineColor = it->second.fill;
+            lineColor.setAlpha(128);
+            painter.setPen(QPen(lineColor, 1));
+            painter.drawLine(worldToWidget(pos.value), worldToWidget(*targetPos));
+        });
+}
+
 void ArenaView::drawBeams(QPainter& painter)
 {
     painter.setPen(QPen(m_visuals->beams.color, m_visuals->beams.widthPx));

src/balancing/ArenaView.h

@@ -39,6 +39,7 @@ public:
 protected:
     void paintGL() override;
     void mousePressEvent(QMouseEvent* event) override;
+    void keyPressEvent(QKeyEvent* event) override;
 
 private slots:
     void onFrame();
@@ -51,6 +52,8 @@ private:
     void drawStations(QPainter& painter);
     void drawScrap(QPainter& painter);
     void drawShips(QPainter& painter);
+    void drawDebugSensorRanges(QPainter& painter);
+    void drawDebugTargetLines(QPainter& painter);
     void drawBeams(QPainter& painter);
 
     float tilePx() const;
@@ -86,4 +89,6 @@ private:
     bool m_finishedEmitted;
 
     std::optional<entt::entity> m_selectedEntity;
+
+    bool m_debugDraw;
 };