Scratch

Scratch

More complexscratch

Lesson Objectives

● Understand the concept of a variable● Using the random function● Move towards● Keep track of score using a variable

Setting up the need for a variable

● Before we learn about variables we must create the “need” for them!

● First of all we will create a baddie which will move towards the player

Move towards

● Baddie moves towards pucman until they touch

● That is game over!● Otherwise it points

towards him● And moves slowly!

Activity

● Add a baddie and make it move towards pucman.

● Use collect version 1 to help you

Items reappears!

● Forever will keep looping, err, forever!● It will repeat whatever is inside it● When collected it will move to a new postion

Random position

● Pick random (under operators) allows you to pick a number between a set of values.

● This allows you to pick a new X and Y position for your item!

Activity

● Get your item to move once collected!

Variables

● A variable is something which can change!● It must have a name (so we can refer to it)● And a value!

● The value can change over time and can be checked● In a loop or a if statement

● A score will be a variable

How a score will work

● Initially set to 0 on game start● When a item is picked up it will increase by

a set amount● On game over it will be displayed!.

Adding a score

● Click on make a variable● Call it score!● You should see the

options shown on the right

Setting score to zero

● This script should be added to the player.

Item code

● The item needs to change the score.● This is added to the item's code as shown

below.

Activity

● Add score to your game.

● If your feeling adventurous.● Open up collect version 2.● See how it works● Add it to your game!