www.computerscienceuk.com programming computer games game design
TRANSCRIPT
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Starter
Y-axis
X-axis-240 240
180
(0, 0)(x,y)
What is the position of the:
1) Star2) Square3) Triangle4) Rectangle5) Cat
-180
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Learning Objectives
• Learning Objectives– Remember the coordinates system in Scratch.– Learn how to program a scrolling background.– Understand how Scrolling Backgrounds work.
• Success CriteriaLevel4/5– To code a scrolling background with support.– To briefly describe how the scrolling background code works.Level6/7– To code a scrolling background mostly from own knowledge.– To explain fully and in detail how the scrolling background code works.
Literacy – Key Words
Sprite A programmable object
Scrolling Background The illusion that the screen is panning / moving across the ground
Coordinates Two numbers to identify the position of an object
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Learning Habits / Skills Required
• Independence - Working effectively alone
• Avoid Distractions - and sustain concentration
• Capitalising - Using resources purposefully
• Perseverance - Overcoming frustration and difficulty
• Reasoning – Thinking rigorously, methodically and giving explanations.
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Starter
Y-axis
X-axis-240 240
180
(0, 0)(x,y)
What is the position of the:
1) Star (-240,180)2) Square (240, -180)3) Triangle (-240, 0)4) Rectangle (0, -180)5) Cat (0,0)
-180
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Project Aim
• You will design and create a computer game…
…but unlike previously we will learn how to program a scrolling
background.…and here is one I made earlier!
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A scrolling background is simply two sprites which move to the left.They are positioned next to each other.
As soon as a sprite goes too far to the left, it is repositioned to the right of the screen.
This gives the illusion of a moving background!
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Y-axis
X-axis
Remember the Invisible Coordinates Grid?
(0, 0)(x,y)
How can we move a sprite to the left along the x axis in scratch?
-240 240
180
-180
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1 2
3
4
5
+
6
Create a new sprite.
Zoom out as far as you can.Paint your
‘ground’ at the bottom of the canvas
So, now go back and edit the same sprite.
At this point scratch will annoyingly centre the sprite…
Choose the ‘Select Tool’ and ‘Zoom Out’ again.
Finally, drag the sprite down to the bottom of the canvas.
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Place first sprite so that it is centred at the bottom of the screen.
Then forever move the sprite to the left (change x by -5).
But, if the position of the sprite goes too far to the left (x pos < -450), move back to the right of the screen (x=450)
Programming The Scrolling Background Sprites
Understanding the Scripts
Block
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Place first sprite so that it is to the right of the screen.
Then forever move the sprite to the left (change x by -5).
But, if the position of the sprite goes too far to the left (x pos < -450), move back to the right of the screen (x=450)
Understanding the Scripts
Block
Programming The Scrolling Background Sprites
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Programming Task 1
’12 Minutes’
Open a new scratch file
Use this presentation to program your own scrolling background
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Programming Task 2
’12 Minutes’
Complete the worksheet explaining the code you have created and how the scrolling works.
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Assessment CriteriaLevel Programming Skills
7• I can produce the code from my own understanding.• I can explain what the code does in detail and in my own
words.
6• I can produce the code mostly from my own understanding
but use the lesson resources for support.• I can explain what the code does in detail and in my own
words
5• I can use the resources to help me code the scrolling
background• I can describe what the code does in my own words
4• I can copy the code to produce the scrolling background• I struggle to describe how it works in my own words
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Learning Habits / Skills Required
• Independence - Working effectively alone
• Avoid Distractions - and sustain concentration
• Capitalising - Using resources purposefully
• Perseverance - Overcoming frustration and difficulty
• Reasoning – Thinking rigorously, methodically and giving explanations.