add a camera mode to spectate soccer in large isometric view (switchable with accel/brake keys) (#4245)

Co-authored-by: luffah <luffah@runbox.com>

src/graphics/camera.cpp

@@ -190,6 +190,7 @@ void Camera::setupCamera()
  */
 void Camera::setMode(Mode mode)
 {
+    if (mode == m_mode) return;
     // If we switch from reverse view, move the camera immediately to the
     // correct position.
     if( (m_mode==CM_REVERSE && mode==CM_NORMAL) || 
@@ -204,6 +205,7 @@ void Camera::setMode(Mode mode)
         m_camera->setTarget(target_position.toIrrVector());
     }
 
+    m_previous_mode = m_mode;
     m_mode = mode;
 }   // setMode
 
@@ -215,6 +217,14 @@ Camera::Mode Camera::getMode()
     return m_mode;
 }   // getMode
 
+// ----------------------------------------------------------------------------
+/** Returns the last kwown mode of the camera.
+ */
+Camera::Mode Camera::getPreviousMode()
+{
+    return m_previous_mode;
+}   // getMode
+
 //-----------------------------------------------------------------------------
 /** Reset is called when a new race starts. Make sure that the camera
     is aligned neutral, and not like in the previous race

src/graphics/camera.hpp

@@ -64,6 +64,7 @@ public:
         CM_CLOSEUP,           //!< Closer to kart
         CM_REVERSE,           //!< Looking backwards
         CM_LEADER_MODE,       //!< for deleted player karts in follow the leader
+        CM_SPECTATOR_SOCCER,  //!< for spectator (in soccer mode)
         CM_SIMPLE_REPLAY,
         CM_FALLING
     };   // Mode
@@ -77,6 +78,7 @@ private:
 
     /** Camera's mode. */
     Mode            m_mode;
+    Mode            m_previous_mode;
 
     /** The type of the camera. */
     CameraType      m_type;
@@ -173,6 +175,7 @@ public:
 
     void setMode(Mode mode);    /** Set the camera to the given mode */
     Mode getMode();
+    Mode getPreviousMode();
     void setKart(AbstractKart *new_kart);
     virtual void setInitialTransform();
     virtual void activate(bool alsoActivateInIrrlicht=true);

src/graphics/camera_normal.cpp

@@ -25,6 +25,7 @@
 #include "input/device_manager.hpp"
 #include "input/input_manager.hpp"
 #include "input/multitouch_device.hpp"
+#include "modes/soccer_world.hpp"
 #include "karts/abstract_kart.hpp"
 #include "karts/explosion_animation.hpp"
 #include "karts/kart.hpp"
@@ -262,6 +263,16 @@ void CameraNormal::getCameraSettings(float *above_kart, float *cam_angle,
             *cam_roll_angle = 0.0f;
             break;
         }
+    case CM_SPECTATOR_SOCCER:
+        {
+            *above_kart = 0.0f;
+            *cam_angle  = 40*DEGREE_TO_RAD;
+            *sideway    = 0;
+            *distance   = -6.75f*m_distance;
+            *smoothing  = true;
+            *cam_roll_angle = 0.0f;
+            break;
+        }
     case CM_SIMPLE_REPLAY:
         // TODO: Implement
         break;
@@ -327,6 +338,21 @@ void CameraNormal::positionCamera(float dt, float above_kart, float cam_angle,
     Vec3 wanted_target = m_kart->getSmoothedTrans()(Vec3(0, above_kart, 0));
 
     float tan_up = tanf(cam_angle);
+
+    if (getMode() == CM_SPECTATOR_SOCCER)
+    {
+        SoccerWorld *soccer_world = dynamic_cast<SoccerWorld*> (World::getWorld());
+        if (soccer_world)
+        {
+            Vec3 ball_pos = soccer_world->getBallPosition();
+            Vec3 to_target=(ball_pos-wanted_target);
+            wanted_position = wanted_target + Vec3(0,  fabsf(distance)*tan_up+above_kart, 0) + (to_target.normalize() * distance);
+            m_camera->setPosition(wanted_position.toIrrVector());
+            m_camera->setTarget(wanted_target.toIrrVector());
+            return;
+        }
+    }
+
     Vec3 relative_position(side_way,
                            fabsf(distance)*tan_up+above_kart,
                            distance);

src/network/protocols/client_lobby.cpp

@@ -1441,11 +1441,19 @@ void ClientLobby::changeSpectateTarget(PlayerAction action, int value,
     if (action == PA_LOOK_BACK)
     {
         if (cam->getMode() == Camera::CM_REVERSE)
-            cam->setMode(Camera::CM_NORMAL);
+            cam->setMode(cam->getPreviousMode());
         else
             cam->setMode(Camera::CM_REVERSE);
         return;
     }
+    if (action == PA_ACCEL)
+    {
+        if (cam->getMode() == Camera::CM_SPECTATOR_SOCCER)
+            cam->setMode(cam->getPreviousMode());
+        else 
+            cam->setMode(Camera::CM_SPECTATOR_SOCCER);
+        return;
+    }
 
     World::KartList karts = World::getWorld()->getKarts();
     bool sort_kart_for_position =
@@ -1513,11 +1521,12 @@ void ClientLobby::addSpectateHelperMessage() const
     core::stringw left = dc->getBindingAsString(PA_STEER_LEFT);
     core::stringw right = dc->getBindingAsString(PA_STEER_RIGHT);
     core::stringw back = dc->getBindingAsString(PA_LOOK_BACK);
+    core::stringw accel = dc->getBindingAsString(PA_ACCEL);
 
     // I18N: Message shown in game to tell the player it's possible to change
     // the camera target in spectate mode of network
-    core::stringw msg = _("Press <%s> or <%s> to change the targeted player "
+    core::stringw msg = _("Press <%s> or <%s> to change the targeted player, "
-        "or <%s> for the camera position.", left, right, back);
+        "<%s> or <%s> for the camera position.", left, right, back, accel);
     MessageQueue::add(MessageQueue::MT_GENERIC, msg);
 }   // addSpectateHelperMessage