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  4. How to process several key events at the same time?
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How to process several key events at the same time?

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  • S Suares

    @raven-worx

    As for the first question I'm not sure. I start from User Input module. Now game doesn't have any GUI and update logic. My main loop is very simple:

    while (true)
    {
      auto cmd = processInput(); // I'm working here.
      update(cmd); // Has only one call cmd->Execute();
      render(); // Empty.
      delay();
    }
    

    As for second one, I don't want to stop moving my tank as soon as another command comes in.

    1. Press only one of the move keys (left, up, right, down) - everything is okay.
    2. Press only fire (space) - everything is okay too.
    3. Hold move key and press (not hold) fire key - failure. I can see fire and move commands in debug messages, but after it my tank can't continue moving while I still hold move button. And I noticed there are no more key events in debug messages after pressing and releasing space key for fire. Hmmm...
    raven-worxR Offline
    raven-worxR Offline
    raven-worx
    Moderators
    wrote on last edited by
    #6

    @Suares said in How to process several key events at the same time?:

    As for second one, I don't want to stop moving my tank as soon as another command comes in.

    yes i know.
    As i said, i simply suspect a bug in your game logic in the key event processing -> processInput()

    --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
    If you have a question please use the forum so others can benefit from the solution in the future

    S 1 Reply Last reply
    2
    • raven-worxR raven-worx

      @Suares said in How to process several key events at the same time?:

      As for second one, I don't want to stop moving my tank as soon as another command comes in.

      yes i know.
      As i said, i simply suspect a bug in your game logic in the key event processing -> processInput()

      S Offline
      S Offline
      Suares
      wrote on last edited by
      #7

      @raven-worx

      Okay, I'll check it once again.

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      • QT-static-prgmQ Offline
        QT-static-prgmQ Offline
        QT-static-prgm
        wrote on last edited by
        #8

        best way for help is to upload your code somewhere (github) and give us a link to the source. Additionally you can point to the (in your opinion) important part of the code. That way we can easier look for other function, you may thought are not important

        S 2 Replies Last reply
        1
        • QT-static-prgmQ QT-static-prgm

          best way for help is to upload your code somewhere (github) and give us a link to the source. Additionally you can point to the (in your opinion) important part of the code. That way we can easier look for other function, you may thought are not important

          S Offline
          S Offline
          Suares
          wrote on last edited by
          #9

          @QT-static-prgm

          It'll be very nice. When I come home I'll push project to github and notify you.

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          • QT-static-prgmQ QT-static-prgm

            best way for help is to upload your code somewhere (github) and give us a link to the source. Additionally you can point to the (in your opinion) important part of the code. That way we can easier look for other function, you may thought are not important

            S Offline
            S Offline
            Suares
            wrote on last edited by
            #10

            @QT-static-prgm

            Hello! I've uploaded project to github.

            Game.cpp line 8 - create and install my custom event filter.
            Game.cpp line 22 - main game loop.
            KeyEventFilter.cpp line 14 - overridden eventFilter method.
            And UserInput class contains queue with user commands.

            Thank you for help!

            raven-worxR 1 Reply Last reply
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            • S Suares

              @QT-static-prgm

              Hello! I've uploaded project to github.

              Game.cpp line 8 - create and install my custom event filter.
              Game.cpp line 22 - main game loop.
              KeyEventFilter.cpp line 14 - overridden eventFilter method.
              And UserInput class contains queue with user commands.

              Thank you for help!

              raven-worxR Offline
              raven-worxR Offline
              raven-worx
              Moderators
              wrote on last edited by raven-worx
              #11

              @Suares
              your Command::Execute() methods are empty?
              I guess your Commands (shared pointers) run out of scope as soon as you execute the next command.

              --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
              If you have a question please use the forum so others can benefit from the solution in the future

              S 1 Reply Last reply
              1
              • raven-worxR raven-worx

                @Suares
                your Command::Execute() methods are empty?
                I guess your Commands (shared pointers) run out of scope as soon as you execute the next command.

                S Offline
                S Offline
                Suares
                wrote on last edited by
                #12

                @raven-worx

                Not exactly. They have one line:

                qDebug() << ...
                

                As for second your sentence. I'm sorry I didn't quite get that. Could you please explain?

                raven-worxR 1 Reply Last reply
                0
                • QT-static-prgmQ Offline
                  QT-static-prgmQ Offline
                  QT-static-prgm
                  wrote on last edited by
                  #13

                  I wonder about the executes, too. You just print things on qdebug, so how you know you are no longer moving when firing?? You're actually never start moving

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                  • S Suares

                    @raven-worx

                    Not exactly. They have one line:

                    qDebug() << ...
                    

                    As for second your sentence. I'm sorry I didn't quite get that. Could you please explain?

                    raven-worxR Offline
                    raven-worxR Offline
                    raven-worx
                    Moderators
                    wrote on last edited by
                    #14

                    @Suares said in How to process several key events at the same time?:

                    As for second your sentence. I'm sorry I didn't quite get that. Could you please explain?

                    But it would be interesting how you exactly implemented the moving. Because thats essential to know when it stops doing what it's supposed to be doing ;)

                    I mean that the commands maybe get deleted because no object holds a reference to it anymore. But again this needs insight how the commands actually work.

                    --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
                    If you have a question please use the forum so others can benefit from the solution in the future

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                    • raven-worxR raven-worx

                      @Suares said in How to process several key events at the same time?:

                      As for second your sentence. I'm sorry I didn't quite get that. Could you please explain?

                      But it would be interesting how you exactly implemented the moving. Because thats essential to know when it stops doing what it's supposed to be doing ;)

                      I mean that the commands maybe get deleted because no object holds a reference to it anymore. But again this needs insight how the commands actually work.

                      S Offline
                      S Offline
                      Suares
                      wrote on last edited by
                      #15

                      @raven-worx

                      If user stop pressing keys - NoCommand will be executed.

                      Please look at UserInput.cpp line 27:

                      return (cmd) ? cmd : std::make_shared<NoCommand>();
                      

                      If there is no command from user - queue is empty that is why I return NoCommand.

                      Definition of this command is:

                      void NoCommand::Execute() noexcept
                      {
                      }
                      
                      raven-worxR 1 Reply Last reply
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                      • S Suares

                        @raven-worx

                        If user stop pressing keys - NoCommand will be executed.

                        Please look at UserInput.cpp line 27:

                        return (cmd) ? cmd : std::make_shared<NoCommand>();
                        

                        If there is no command from user - queue is empty that is why I return NoCommand.

                        Definition of this command is:

                        void NoCommand::Execute() noexcept
                        {
                        }
                        
                        raven-worxR Offline
                        raven-worxR Offline
                        raven-worx
                        Moderators
                        wrote on last edited by
                        #16

                        @Suares
                        yes, but still it's not clear how the actual moving is implemented...

                        --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
                        If you have a question please use the forum so others can benefit from the solution in the future

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                        • QT-static-prgmQ Offline
                          QT-static-prgmQ Offline
                          QT-static-prgm
                          wrote on last edited by
                          #17

                          you need to have something like this:

                          void updateScene()
                          {
                              littleMan.positionX += moveX;  // you remember what i told you about the moveX variable and the signal?
                              littleMan.positionY += moveY;
                          
                              for(auto& it : boldList)
                                  it.update();  // while this update function will move your bold one step forward in the fire direction.
                          }
                          

                          and your slot for firing will add an bold to the boldList. An bold can be a struct like this:

                          struct Bold {
                              QPoint position;
                              QVector2D direction;
                              int speed;
                          }
                          
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                          • S Offline
                            S Offline
                            Suares
                            wrote on last edited by
                            #18

                            Please wait. I need more time to implement real moving for my tank.
                            I'll show you my way as soon as possible.

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                            • QT-static-prgmQ Offline
                              QT-static-prgmQ Offline
                              QT-static-prgm
                              wrote on last edited by
                              #19

                              Man, how you know you stop moving, when you never implemented moving???

                              S 1 Reply Last reply
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                              • QT-static-prgmQ QT-static-prgm

                                Man, how you know you stop moving, when you never implemented moving???

                                S Offline
                                S Offline
                                Suares
                                wrote on last edited by
                                #20

                                @QT-static-prgm

                                I implemented movement. If don't belieave you can build project :)
                                Tank moves, but I can't move and fire at the same time. I want to fix it.

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                                • QT-static-prgmQ Offline
                                  QT-static-prgmQ Offline
                                  QT-static-prgm
                                  wrote on last edited by
                                  #21

                                  D:\workspaces\Qt_default\BattleCity-master\include\Game.h:44: Fehler: 'atomic' in namespace 'std' does not name a template type

                                  Is it just me, or is the code a little unreadable? @raven-worx

                                  @Suares why are you always using {} instead of ()??

                                  KeyEventFilter* kef = new KeyEventFilter{ _userTank, this };
                                  Game{ argc, argv }
                                  

                                  ok this code is really ugly (in my opinion) but if i understand it right you are doing this:

                                  get key press and generate a Commando from it,
                                  save them in a queue,
                                  remove the commando from the queue and execute the command, till the list is empty.

                                  So if you press the key it is on the queue once. you take it, execute and forgot about it.

                                  Again why don't you make something like this:

                                  class tank{
                                  ...
                                  QPoint m_position;
                                  QVector2D m_speed = {0,0};
                                  
                                  void addSpeed(QVector2D speed){
                                  m_speed += speed;
                                  }
                                  update()
                                  {
                                  m_position += m_speed;
                                  }
                                  
                                  }
                                  
                                  struct Bold{
                                  QPoint(position);
                                  QVecotr2D(direction);
                                  int speed;
                                  }
                                  
                                  MainWindow(){
                                  
                                  private:
                                  
                                  tank* myTank = new tank;
                                  QVector<Bold> m_bolds;
                                  
                                  addbold(tank* tank)
                                  {
                                  Bold newBold = {tank.getPos, tank.getDirection, 100};
                                  m_bolds.pushback(newBold);
                                  }
                                  
                                  mainLoop()
                                  {
                                  myTank->update();
                                  
                                  for(auto& it : m_bolds)
                                    it.position += it.direction * speed;
                                  
                                  render();
                                  }
                                  
                                  keyPressEvent()
                                  {
                                   if(upPress)
                                    tank->addSpeed(0,1);
                                  else if(upRelease)
                                    tank->addSpeed(0,-1);
                                  if(downPress)
                                    tank->addSpeed(0,-1);
                                  else if(downRelease)
                                    tank->addSpeed(0,1);
                                  else  if(leftPress)
                                    tank->addSpeed(-1,0);
                                  else if(leftRelease)
                                    tank->addSpeed(1,0);
                                  if(rightPress)
                                    tank->addSpeed(1,0);
                                  else if(rightRelease)
                                    tank->addSpeed(-1,0);
                                  else if(spacePress)
                                    addBold(tank);
                                  
                                  }
                                  
                                  }
                                  
                                  }
                                  
                                  }
                                  

                                  you need just your tank class, your MainWindow and a struct for the bold. Your Project has: 7(!!) Classes

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