Transcript file

 We will be creating a spaceship that simulates real
movements in space.
 The spaceship will fire a laser beam that can destroy
targets.
 The spaceship will be able to pass through the edges
of the screen
 Controls:


Up arrow will provide forward thrust
Right and left arrows will turn the ship
Since we are going to be
creating a spaceship, set
the stage background to
be stars.
It can be found in the
Nature folder.
Draw a Spaceship
sprite.
Make sure you point the
ship to the right.
Make two costumes,
one with flames and
one without.
Create the following
Variables: (For this
sprite only)
DirectionChange
NewX
NewY
Thrust
We need to create three
event scripts:
Up Arrow
Right Arrow
Left Arrow
We will begin with the
Up Arrow script.
Drag a when Space Key
pressed block to the Ship
sprite script area and
change it to up arrow.
Connect a repeat until
block to the when up
arrow key pressed block.
Under Operators,
drag an not operator
block into the repeat
until block.
Go to Sensing and put
a key up arrow pressed?
block into the not block.
Put a next costume
block in the repeat until
block.
Put three change
DirectionChange by
blocks into the repeat
until block.
Change the variables to
Thrust, NewX, and
NewY
Put a value of 0.1 in the
change Thrust by block.
Drag two multiplication
operator blocks into the
script area.
Put the Thrust variable
block into the left side
of both multiplication
operator blocks.
Put a sqrt of 10 block on
the right side of each
multiplication block.
Change one of the sqrt
of 10 blocks to sin of 10
Change the other sqrt of
10 block to cos of 10
Put the Thrust * sin of
10 block into the change
NewX by block.
Put the Thrust * cos by
10 block into the change
NewY block
Go to motion and put
a direction block into
the sin of and cos of
blocks.
Put a switch to costume
NoFlames block
underneath the repeat
until not key up arrow
pressed? block.
Put a set Thrust to 0
block under the switch
to costume NoFlames
block.
Now that we have
finished the Up Arrow
scripts, we need to do
the Right Arrow
script and Left Arrow
script.
Create a when right
arrow key pressed block
and connect the blocks
as shown in the image
to it.
Create a duplicate of
the when right arrow
key pressed blocks by
right clicking the when
right arrow key pressed
block and clicking
duplicate.
Alter this newly
duplicated block so it
matches the image to
the right.
Up, Right, and Left
represent the user
controls for the ship.
However, the ship will
not move until we put
the Action code for the
computer to take the
commands and
translate them to
movement.
Create a when Green
Flag clicked block and
connect the specified
blocks as shown in the
image to the right.
Create another when
Green Flag clicked
block and connect the
blocks as shown in the
image to the right.
This will reset the
variables and allow the
ship to pass through the
edges of the screen.
Click the Green flag
and test your ship!
We want a laser beam
to travel to a target and
then stop traveling
when it hits a target.
We also want the laser
beam to go back to the
ship and hide when not
being fired.
Click Paint New
Sprite and draw a laser
beam.
Create the variables as
shown in the image to
the right for the Laser
sprite.
Create a new when
Green Flag clicked
block and connect the
blocks as shown in the
image to the right to it.
This allows the laser
beam to travel a set
distance and check its
status (fire or not fired)
Create a new when
space key pressed block
and connect the blocks
as shown in the image
to the right to it.
This makes it so when
the laser is fired, it’s
fired in the same
direction the ship is
facing.
Test your laser beam!
Our final step is to
create targets for our
space ship to shoot at.
Create a new Sprite.
For this newly created
sprite, create a new
when Green Flag
clicked block and
connect the blocks as
shown in the image to
the right.
This will glide the target
sprite around in
random directions.
Complete the when
Green Flag clicked
block by connecting the
additional blocks as
shown in the image to
the right.
This will now cause the
sprite to disappear and
re-appear if it is hit by
the laser beam.
 Congratulations! You’ve finished creating your own
space ship game.
 See the next slide for challenges.
 Play a sound every time the laser beam is fired and
whenever the laser successfully hits a target.
 Add a score feature that increments when the laser
beam hits the target and decrements when the target
hits the space ship.
 Add more targets
 Implement your own creative features!