251,338
Views
Beginner
Level
117
Comments
Crash Course 2: Invaders - Part 10
by Hectate (Updated on 2015-05-02)
Part 10: Enabling Our Ship to Fire Bullets
Step 73: Our next Event will create a Bullet Actor and set it in motion when the player presses a keyboard key. Click the + Add Event button, mouse over Input, and select Keyboard. Remember, we should already be in the Ship's events screen to create this.
Step 74: On the block that appears, set the control dropdown to action 1, as shown.
Step 75: Now we need to grab two blocks, one that creates our Bullet Actor and another that sends it on its way.
The first is under Scene -> Actors in the Palette. The second is under Actor -> Motion.
Select the Bullet Actor Type by clicking on the dropdown on the create Actor Type block, and in the blue push [Actor] block, change the [Self] field to [last created actor] and [gently] to [sharply]. Snap them together into the Event block, as shown.
Step 76: Next, we need to set where the Bullet is created and the direction it should travel in. For the x and y values, set them to x of self and y of self, which is the current position of the Ship on screen. This block is in Actor > Position. Alternatively, cClick on each dropdown (for x and y) to choose the x of self block from the Actor category in the Block Picker. Then switch the [x] to [y] in the second block, as shown.
Step 77: From here, we set the direction and force the Bullet Actor will launch at in the push [Last Created Actor] block. Set xDir to 0 (we only want the Ship to shoot bullets toward the Enemy Ships, which is up, not horizontally) and yDir to -1. Remember, that “up” on a computer screen is in the negative y direction. Lastly, set force to 40.
Test the game again, and press Action 1 to shoot your bullets (should be Z by default).
We now need to ensure our Bullet Actors are destroyed when they collide with the Enemy Ships and when they leave the screen.
117 Comments
Use this image for fixing events:
https://img.itch.zone/aW1nLzMyNjE3N zMucG5n/original/s7KyLW.png
(l fixed this)
1
For that had problem with the bullet listen here:
At ''Create (chosen Bullet) at ( x: change the ''Last Created Actor'' with Ship and ( y: change the ''Last Created Actor'' with Ship
Make this:
Create [ Bullet ] at ( x: [ [ x ] of [ Ship ] y: [y] of [ Ship ] ] ) at [ Front ]
If this helped you, thank you from me.
1
Hi,I have a problem with my bullet actor. When i press "z" my bullets are appearing behind of me.I would really appreciate for your help
1
Solution to people with Peruvius' problem, few messages earlier:
(probably the same issue with other people having the bullets spawn at top-left corner)
Don't use Actors > Motion > x/y-speed of Self
This is indeed the SPEED of your ship. So if you are stationary when you shoot, the bullet will spawn on the top-left corner of the screen (0,0).
If you are moving to the right, you have a speed of 20, so it will spawn at (20,0). This is still very close to the top-left corner.
The correct item is to use Actors > Position > x/y of Self.
Or if you want to use the selection menu, drag the old "x-speed of self" -block to trash, click the empty dropdown, and select Actor > Basics > x of Actor. Afterwards, change the "Actor" to "Self". Do the same for block (now also remember to change x to y).
1
I can get the bullets to spawn, but they appear in the upper left corner of the screen, regardless of where the ship is on screen. I'm fairly sure I have the parameters set right [create bullets at (x: x-speed of ship y: y-speed of ship) at front] over [push last created actor sharply towards (x-dir:0 y-dir -1) at 40 force].
Hopefully I conveyed this as clearly as I could, and thank you for your help.
2
Hi... ummm so my bullets arent even making it to the enemies. They stop about half way up the screen. I have checked everything 1000 times and cant find anything wrong with them. what should i do or where did i go wrong?
2
