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    Help me find a way to make the lasers fire in a certain direction.

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    • BurntRice
      BurntRice last edited by

      I want my existing lasers to keep on moving. I have also implemented your idea of rewriting my update function.
      I really don’t know how to though. If I use a touch.began method, it runs once, but stays in it’s place.
      Am I forgetting to add something?

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      • JonB
        JonB last edited by

        Okay, let's try this again.

        If you want your laser to move, the movement code must be called EVERY time update is called. There should be no if statements around the for loop that moves the lasers.

        In your old code the laser loop was inside the if statement that checked for the laser button touch. That's why it doesn't move when your finger is up. You will need to update your loop because the direction variable that you use for moving the lasers must be define inside the loop, because it can be different for every laser. You'll need to grab the laser rotation for each laser to figure that out.

        Post your new updated 5 line update method. And post your update_laser_postions function or whatever you called it.

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        • BurntRice
          BurntRice last edited by

          def update(self):
          self.handle_button_presses()
          self.move_lasers()
          if random.random() < 0.01:
          self.spawn_item()

          def handle_button_presses(self):
              for touch in self.touches.values():
                  if touch.location in self.LeftCrtl.bbox:
                      new_x = self.Player.position.x - 5
                      self.Player.rotation = math.pi/2
                      if new_x >= 0 and new_x <= 1100:
                          self.Player.position = (new_x, self.Player.position.y)
          
                  if touch.location in self.RightCrtl.bbox:
                      new_x = self.Player.position.x + 5
                      self.Player.rotation = math.pi*3/2
                      if new_x >= 0 and new_x <= 1100:
                          self.Player.position = (new_x, self.Player.position.y)
          
                  if touch.location in self.UpCrtl.bbox:
                      new_y = self.Player.position.y + 5
                      self.Player.rotation = 0.0
                      if new_y >= 0 and new_y <= 800:
                          self.Player.position = (self.Player.position.x, new_y)
          
                  if touch.location in self.DownCrtl.bbox:
                      new_y = self.Player.position.y - 5
                      self.Player.rotation = math.pi
                      if new_y >= 0 and new_y <= 800:
                          self.Player.position = (self.Player.position.x, new_y)
          
          def move_lasers(self):
              for touch in self.touches.values():
                  if touch.location in self.laserButton.bbox:
                      new_laser = SpriteNode('shp:Circle')
                      new_laser.x_scale = 0.25/1.0
                      new_laser.y_scale = 0.25/1.0
                      new_laser.position = self.Player.position
                      new_laser.rotation = self.Player.rotation
                      direction = Vector2(-math.sin(new_laser.rotation), math.cos(new_laser.rotation))
                      self.add_child(new_laser)
                      self.lasers.append(new_laser)
                      for l in self.lasers:
                          l.position += direction*75
          
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          • dereq
            dereq last edited by

            This post is deleted!
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            • JonB
              JonB last edited by

              for l in self.lasers:
                              l.position += direction*75
              

              That is the code that moves a laser beam, right?

              In words, can you explain under what conditions this code runs?

              Does that code execute EVERY time update is called, or is there some logic that controls when it will run?

              Hint, look above it for any for loops or if statements.

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              • arsartindustry
                arsartindustry last edited by

                This post is deleted!
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                • BurntRice
                  BurntRice last edited by

                  The code runs whenever the laser button detects that someone has touched it.

                  JonB 1 Reply Last reply Reply Quote 0
                  • JonB
                    JonB @BurntRice last edited by

                    @BurntRice but you told me that you want lasers to MOVE even when someone is not currently touching the button.

                    So, you must move the MOVE code out from inside the for touch in self.touches loop.

                    Your code has two parts:

                    • Create a new laser object when person touches the button
                    • Move all of the existing lasers

                    The first part should only happen when user is touching the button.

                    The second part should happen always.

                    Erase your for l in self.lasers code. Now, write new movement code inside a new function, which you will call from update. You will need to redefine direction inside your loop -- it is not the same direction variable that is used inside your creation code. for now, hardcod direction=Vector2(0,1) just so you can get something to work. Later you will use the laser rotation to determine direction.

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                    • BurntRice
                      BurntRice last edited by ccc

                      I’m still working on it, but I added this:

                      def update_lasers(self):
                              for l in self.lasers:
                                  l.direction = Vector2(0,1)
                                  l.rotation = self.Player.rotation
                                  l.position = l.position + l.direction
                      

                      I just want to check if I’m getting side tracked or not.

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                      • JonB
                        JonB last edited by

                        When a laser is moving, it should move based on IT's rotation,not the player rotation. You might move after the laser gets fired, but you want the laser to go straight.

                        So delete the line updating the rotation. The rotation was set when you spawn the laser.

                        This code should work, but of course the laser always goes in one direction. So next, you can redefine direction using the l.rotation, similar to the way you calculated it when you spawn the laser

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                        • BurntRice
                          BurntRice last edited by

                          I think I’ve finally done it! It works, as it shoots in the way I want it, and keeps on travelling even when I haven’t touched it, thanks.
                          All I have to do is add a action so I can’t spam or hold down on the button. What is the best way to add this?

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                          • BurntRice
                            BurntRice last edited by

                            Also, I would also like to know how to code screen wrapping.

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                            • ccc
                              ccc last edited by ccc

                              player.location.x %= screen.width
                              player.location.y %= screen.height
                              
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                              • BurntRice
                                BurntRice last edited by

                                Oh, thanks.

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                                • BurntRice
                                  BurntRice last edited by

                                  Wait, how do find the screen width and height? And what about location?

                                  cvp 1 Reply Last reply Reply Quote 0
                                  • cvp
                                    cvp @BurntRice last edited by

                                    @BurntRice said:

                                    how do find the screen width and height

                                    ui.get_screen_size() --> width,height

                                    BurntRice 1 Reply Last reply Reply Quote 0
                                    • JonB
                                      JonB last edited by

                                      Re spamming, one approach is, in your button handling code, to keep track of self.t, and self.lastfire_time. When current time minus last fire time is > some value, reset the last fire time to current time, and fire a laser. Otherwise, pass

                                      BTW, in your laser loop, you will need to check if the laser is off screen (not in self.bounds), then delete the object from the scene. Otherwise your scene will eventually bog down or crash because it is moving millions of laser objects.

                                      This could also be done in your check_collisions method where you see if your lasers hit your enemies.

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                                      • BurntRice
                                        BurntRice @cvp last edited by

                                        @cvp And what about location?

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                                        • JonB
                                          JonB last edited by ccc

                                          position, not location.

                                          If you want to wrap, you need to fundamentally change your button logic, since you check limits

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                                          • BurntRice
                                            BurntRice last edited by BurntRice

                                            I have added this:
                                            width, height = ui.get_screen_size()
                                            And then added this later:
                                            if self.Player.position.x <= 0 or self.Player.position.x >= 1112:
                                            self.Player.position.x %= width
                                            if self.Player.position.y <= 0 or self.Player.position.y >= 834:
                                            self.Player.position.y %= height
                                            This didn’t work. I checked if I had gotten the width and height variables in a seperate script, and I did. I am now stumped.

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