Harry Potter Scratch Game - s3.amazonaws.com€¦ · Harry Potter Scratch Game 44 Extensions • Speed up the Bludger each time a snitch has been caught – Will need a variable for

Harry Potter Scratch Game 1

Harry Potter Scratch Game


The Game• Use the arrow keys

to move Harry Potter – to catch the golden

snitch

– to avoid being hit by the bludger


Create a New Folder In Your Drive:

Scratch Folder Name it…..Harry Potter

• Navigate to the HarryPotter folder In Your Gaggle Drive and go to the Apps > Digital Locker


Go to the Shared Folder Called Harry Potter

• Open the folder and download all of the pictures needed to create this Scratch Game or get your own if can find and create better ones.


Getting Started• Start Scratch

• Delete the cat– Click on scissors

and then the cat

– or right click on the cat and pick delete


Change the Background• Click on the stage

to select it

• Click on the Backgrounds tab

• Click on the import button


Select New Background• Navigate to the

HarryPotter folder Select the Stadium and click OK


The Stage is Set


Add Harry Potter• Click on the folder

with a star on it to add a sprite from a file

• Navigate to the HarryPotter folder

• Add Harry


The Game so Far


Scratch is Event Driven• You can make

things happen when events occur– such as a key is

pressed– the green flag is

clicked on– a message is

received


Making Harry Move• Click on the Scripts Tab• Click on Control and drag

out – when space key pressed– Change to left arrow key

• Click on Looks and drag out– switch to costume – Change to Harry_Left

• Click on Motion and drag out– change x by 1– click on 1 and change to -4


The Scratch Stage• The Scratch stage is 480 pixels wide and

360 pixels high.

-240 240

180

-180

x increases x decreases

y increases

y decreases


Add Other Key Scripts• When right arrow

– change to Harry_Right costume

– change x by 4

• When down arrow– change y by -4

• When up arrow– change y by 4


Add the Golden Snitch• Click on the folder

with a star on it to add a sprite from a file

• Navigate to the HarryPotter folder

• Add the snitch


Harry and the Snitch


Snitch Behavior• In a 'normal' Quidditch game the game is

over when the snitch is caught

• But, in this game you will have to catch 10 snitches to win.– you will need to keep track of the number

caught

• Each time the snitch is caught it will hide and reappear in a new random location


Variables• To remember how many

snitches were caught we will need a variable– the value stored in a

variable can change (vary)• Click on the Variables

button• Then click on Make a

Variable• Enter a name for the

variable• Use the default of For all

sprites• Click on OK


Starting• Scratch games and

animations usually start when you click the green flag

• Click on Stage to select it• Click on Scripts to program• Click on Control to see the

control blocks• Drag the "when green flag

clicked" block out• Click on Variables

– drag the "set Snitches Caught to 0"


Messages• Scripts can receive messages

and broadcast messages– blocks are in the Control

area• Click on the snitch sprite,

then Scripts then Control• To create a message drag out

the "when I receive" and click on the down arrow– then on new…

• Give the message the name Caught– click on OK


More about Messages• Broadcasting and receiving messages is

how sprites communicate with each other– it doesn't cause anything to be printed or

appear

– it does execute scripts that receive the message

– All broadcasted messages should have one or more sprites that receive the message


Responding to Caught• Hide the snitch

– drag hide from Looks• Add one to the number

of snitches caught

– drag from Variables• Change the x and y

values– drag from motion– replace values with

random numbers • from Number

• Show the snitch– drag from Looks

• Play a sound– drag from Sound


Conditional Execution• Sometimes we want to execute a block or

several blocks if some condition is true– use sensing blocks or number blocks that

return true or false– these have 6 sides (hexagon)

• The snitch is captured if Harry is touching it

• Use an if from Control to check if Harry is touching the snitch sprite


Catching the Snitch• If the Harry Potter sprite is

touching the snitch sprite – add if

• from Control– add "touching …" and change

to "Sprite3"• from Sensing

• Broadcast the Caught message

• from Control

• Right click on the if block and pick "duplicate" – and add to all the other

scripts for Harry Potter


Catching the Snitch• Right click on the

if block and select duplicate

• Drop the copy on the other scripts

• Move the scripts to see them better


More on Conditionals• Sometimes we want to execute some

blocks if a condition is true and other blocks if it is false

• Use a if and else block from Control for this


Winning the Game• In the snitch script

that receives the caught message– drag in a if and else

• from Control– place it after the

change Snitches Caught by 1

– move the last 3 tiles into the else part

• if you have won these don't need to execute


Winning the Game– drag in a "blank = blank"

• from Number

– drag in "Snitches Caught" to the first blank area

• from Variables

– click on second blank area and type in 10

– drag in a broadcast block

• Create new message "Won"


Telling the User• Click on Stage• Click on

Backgrounds• Click on Import• Navigate to

HarryPotter folder• Select Congrats

– click on OK


Stage Scripts• Click on Stage and Scripts• Set the initial background

to the stadium – when the green flag is

clicked• from Looks

• When the stage receives a Won message– from Control– switch background to

Congrats• from Looks


Hide Other Sprites• If the user has won

– hide the other sprites• Harry Potter• Snitch

– You can click on the "when I receive Won"

• and drag it to the snitch sprite to copy it

• then click on the snitch sprite and scripts to check the copy worked


When Game Starts• If the user wins and

Harry and the Snitch hide when you restart the game– they won't show again

if you start a new game

• Add "when green flag clicked" show to:– Harry – Golden Snitch


Making it Harder• add a Bludger

• if the Bludger hits Harry he "dies"– start with 3 lives

– lose a life each time Harry dies

• if Harry loses all 3 lives you lose the game


Add Lives Variable• Click on Variables

• Click on Make a variable

• Enter Lives

• Drag display to top right


Start with 3 Lives• Click on Stage

• Click on Scripts

• Add "set Lives to 0"

• Click on 0 and change to 3


Painting a Bludger• You can paint a new

sprite– click on the paintbrush

with a star on it

• Click the color• Click the circle shape

tool• Click and drag to make

the circle• Click on OK


Loops • Sometimes you want to repeat blocks until

the game ends or something happens

• Use a forever block to repeat actions until the game ends– use a stop all block to stop all scripts

• Use a repeat block to repeat some actions a given number of times


Bludger Scripts• When the green flag

is clicked loop forever– set x to 260– hide the bludger– wait for some

random amount of time between 3 and 5 seconds

– show the bludger– Glide to the

opposite side • x is -260• random y from -

145 to 145


Bludger Scripts• When the green flag

is clicked, loop forever– check if touching Harry

• play a sound• reduce the number of

lives• check if lost

– lives = 0

• wait till not touching Harry

– or you will die quickly


Tell User Game Over• Click on Stage• Click on

Backgrounds• Click on Stage• Select Background

Tab• Paint/Create Text:

Game Over• Click OK


New Stage Script• Click on Scripts• Add "when I receive Lost"

– from Control

• Add "switch background Game Over"– from Looks

• Add "stop all"– from Control

• Add "stop all" to the end of when receive "Won" script too


Hide Sprites When Lose• When the game is

lost– hide Harry

– hide the Snitch


Project Notes if signed up online and can upload

• Click on the notepad in the top right corner

• Type in project notes if live and signed up.

• You can upload your project to the Scratch web site– Click on Share!

– See it at http://scratch.mit.edu


Extensions• Speed up the Bludger each time a snitch has been caught

– Will need a variable for "Time to Cross"– Reduce the variable each time each time the snitch is caught

• Add background music– Import Theme.wav– Add a script to the stage

• When the green flag is clicked• Loop forever playing the theme and waiting for it to finish

• Make the Bludger come from any direction– and glide across to the opposite side

• Add Beaters who can hit the Bludger away– Using the space key

• Add a time limit – That counts done

Documents

Harry Potter Scratch Game - s3.amazonaws.com€¦ · Harry Potter Scratch Game 44 Extensions • Speed up the Bludger each time a snitch has been caught – Will need a variable for