1. August 25
Intro to CS

2. Let’s review last class…
Blocks 1
Sprite 3
Comments 6
Stage 4 1 2 3 4 5 6
Script 5
Script area 2

3. Let’s review last class…
Identify by name the parts of SNAP!
Give examples of blocks in each category
Explain the function of control blocks
Build, comment and run a simple SNAP! script
Script, Blocks, Stage, Sprite
Controls the actions of the Sprite
Hello World!

4. What you’ve learned SNAP IDE: How to login
How to select the desired palette of instructions
What is the “Script Area”
What is the “Stage” area
How to make a “comment” and attach to an instruction block

5. What you’ve learned
Motion blocks: Control blocks Looks and Pen instructions

6. Today’s Objectives How to get help Boolean Operations
Introducing Project #1
How to “design” before you “code”
Adding and rotating a Sprite

7. Today: Exploring More Blocks

8. Advanced Blocks

9. Advanced Blocks

10. Go to File
Import Tools (to get additional functions.

11. Help! (or, How to get instruction help)
Cursor on instruction
Right Click
Choose “help…”
On a MAC:
CTRL + Click == right click

12. Result of right click  help

13. Today’s Objectives How to get help Boolean Operations
Introducing Project #1
How to “design” before you “code”
Adding and rotating a Sprite

14. Boolean Operations What is a BOOLEAN OPERATOR?
Conditions that when evaluated result in the answer of “true” or “false.”
George Boole, Mathematician
Examples:
The sun is shining right now in San Jose (TRUE).
I am under 16 years old. (FALSE)
The classroom light switch is on. (TRUE)

15. Boolean Operations Examples:
You can create IF / Then situations using Boolean Conditions
Examples: IF
The sun is shining right now in San Jose,
I am under 16 years old,
The classroom light switch is on,
THEN
Turn off the street lights.
Make sure I am not driving.
The lights should be on.

16. Boolean Operations Examples:
You can COMBINE operations, and the result still will be either
True or False.
Examples: IF
It is between 8am and 2pm,
AND
It is a Friday,
THEN
Ring the Lincoln bells.

17. Boolean Operations Examples:
You can COMBINE operations, and the result still will be either
True or False.
Examples: IF
The light switch by the classroom door is on, OR
The light switch by the library door is on,
THEN
The lights should be on.

18. AND (both have to be true)
Battery
Switch A Switch B
Is Switch A closed?
Is Switch B closed?
The Lightbulb ON? No
False
Yes
TRUE!

19. OR (either one has to be true)
Battery
Switch A
Switch B
Switch A closed
Switch B closed?
Lightbulb ON No
False
Yes
True

20. NOT (the inverse) In these cases, Yes ==True == 1 No == False == 0
Battery
Switch A
Switch B
Switch A closed
Switch A is NOT closed No
True (Yes)
Yes
False (No)
In these cases,
Yes ==True == 1
No == False == 0

21. SNAP! Operators How do Boolean Operators in SNAP! work? The same way.
Conditions that when evaluated result in the answer of “true” or “false.”

22. SNAP! Operators If BOTH Condition “A” and Condition “B” are true,
then TRUE
If EITHER
Condition “A” or Condition “B” is true,
then TRUE If
NOT Condition “A”
then TRUE
When you NEST boolean operators, solve inside out

23. Lab: Build this compound Boolean expression
If BOTH
Condition “A” and Condition “B” are true,
then TRUE
If EITHER
Condition “A” or Condition “B” is true,
then TRUE If
NOT Condition “A”
then TRUE
When you NEST boolean operators, solve inside out

24. Lab: Solve this compound Boolean expression
A and (B or (Not A) ) No
Yes A B
A and (B or (Not A) ) 1

25. Lab: ANSWER A B (Not A) (B or (NotA) A and (B or (Not A) ) No Yes
No (False)
Yes (True) A B
(Not A)
(B or (NotA)
A and (B or (Not A) ) 1

26. Where are Boolean operators used?
These are instructions from the “Control” palette
The triangular shape is a clue that a Boolean
operator needs to be inserted.
These instructions “Control” the code flow based
on when a condition becomes true or off
Let’s look at some examples

27. Boolean Example1 LAB: PROGRAM AND RUN THIS EXAMPLE.
What does this code do?
Notice the triangular Boolean operator “fits” into the empty triangular slot in the “repeat”
LAB: PROGRAM AND RUN THIS EXAMPLE.

28. Boolean Example2 LAB: PROGRAM AND RUN THIS EXAMPLE.
What does this code do?
Notice the “Control” block which
Starts the code.
Notice the triangular Boolean operator “fits” into the empty triangular slot in the “repeat”
LAB: PROGRAM AND RUN THIS EXAMPLE.

29. Today’s Objectives How to get help Boolean Operations
Introducing Project #1
How to “design” before you “code”
Adding and rotating a sprite

30. Introducing Project #1
Play “The Platform” Project – Watch for these things
What does Mario do? At the Edges?
What does the Tree do? At the Edges?
What does the Mountain do? At the Edges?
What does the Gremlin do? At the edges?

31. The Platform Game Video

32. Project #1: The Platform Project
Play “The Platform” Project – What did you see?
What does Mario do? At the Edges?
What does the Tree do? At the Edges?
What does the Mountain do? At the Edges?
What does the Gremlin do? At the edges?

33. Specification and grading ( Hero(“Mario) )
Requirement
Mario turns to the right on right arrow key
Mario turns to the left on left arrow key
Mario performs an in-place animated walk if you hold down either arrow key
Mario jumps based on some input

34. Mario Specification and grading ( Scenery)
Requirement
There are least two scenery sprites (example: a tree and a mountain)
Scenery sprites are layered with Mario (example: appropriate layering blocks are in your program)
Scenery sprites move based on Mario’s movement
Scenery sprites move at different speeds (e.g. the mountain far away moves slower than the nearby tree – just like when you look out a car window)
Scenery sprites roll over when the fall of the stage

35. Mario Specification and grading ( Enemy )
Requirement
There is at least one on-ground enemy
Enemy sprite always moves towards Mario
Enemy sprite re-appears/rolls over correctly
Enemy sprite is animated when it moves
If Mario does not jump, he runs into the enemy and the game ends nicely and properly
Mario can jump over the enemy

36. Mario Specification and grading ( Good programming )
Requirement
Good programming #1: Program has clear start and stop
Good programming #2: Program is repeatable and initializes state correctly
Good programming #3: Use of at least 10 comments in your code

37. Project Grading Guidelines
When helping someone else, keep your hands off their keyboard and mouse.
They must do all the typing.
Talking through a coding project problem is ok: copying is plagiarism, and forbidden.
You will lose 50% of your score, and your parents will be notified.

38. One version of Code This code does everything
Mario, Gremlin, Tree, etc.
Looks Intimidating
Not commented

39. Today’s Objectives How to get help Boolean Operations
Introducing Project #1
How to “design” before you “code”
Adding and rotating a Sprite

40. How to approach this large amount of code
Break large problem into small ones
You must think first !
Look for patterns in real world situation
Find a pattern - write one block - use it everywhere
Design your structure
After all of that…then you may begin coding

41. Design first – small manageable sections
Mario
Initialize : costume, position
Right Arrow : costume, move right, costume change, move right, etc (check for Right Edge & wrap)
Left Arrow : costume, move left , costume change , move left , etc (check for Left Edge & wrap)
Up Arrow : move up, wait, move down
R.I.P. : Mario and Gremlin are touching

42. Design first – small manageable sections
Tree
Initialize: position
Right Arrow: point left , move left, check for left edge (wrap or bounce)
Left Arrow: point right, move right, check for right edge (wrap or bounce)

43. Designed code (Hero) Code self-documented Code smaller chunks
Easy to debug
Each Block has 6 or 7 lines
of code.

44. Today’s Objectives How to get help Boolean Operations
Introducing Project #1
How to “design” before you “code”
Adding and rotating a Sprite

45. Adding a new Sprite Click new Sprite button at bottom of stage -
Click on “Costumes”
Drag image from desktop into costume area
Click on “Scripts”
Write the code for this Sprite

46. Lab: Add, remove and reposition sprites
Open SNAP!
With your blank project, name it “August2425Labs”

47. Lab: Add, remove and reposition sprites
Find an image that you would like for your Sprite
Add it to your workspace as a Sprite “costume”
Replace existing costume with your new one
Repeat this process – but only this time draw a STICKMAN Sprite with one leg longer than the other using the graphical editor.

48. What worked? What was difficult?
Lab Recap:
Discussion
What worked?
What was difficult?

49. Rotating a Sprite

50. Lab: Rotation Create this simple script, then run it.
Pick your stick figure figure Sprite with one leg purposely longer than the other
TIMING: 4 mins (total 8Mins)
ACTUAL: 4 min (10 total),
Today, let’s do a deeper dive into the Pen block set.
Who can tell me what these do:
- Pen Up
- Pen Down
- Clear
- Set Pen Color?
- Set Pen Shade
- Stamp
Who can tell me what the following block does?

51. Lab: Rotation Did any of you get this? Why?
Click each of the three buttons and try it again.
What was different?
What happens with “rotate 180 degrees?”
TIMING: 4 mins (total 8Mins)
ACTUAL: 4 min (10 total),
Today, let’s do a deeper dive into the Pen block set.
Who can tell me what these do:
- Pen Up
- Pen Down
- Clear
- Set Pen Color?
- Set Pen Shade
- Stamp
Who can tell me what the following block does?

52. Did any of you get this? Why?
Lab 3: Recap
Did any of you get this? Why?
TIMING: 4 mins (total 8Mins)
ACTUAL: 4 min (10 total),
Today, let’s do a deeper dive into the Pen block set.
Who can tell me what these do:
- Pen Up
- Pen Down
- Clear
- Set Pen Color?
- Set Pen Shade
- Stamp
Who can tell me what the following block does?
can rotate
only face left/right
can’t rotate

53. What worked? What was difficult?
Lab Exercise Recap:
Discussion
What worked?
What was difficult?

54. Let’s move the rotation point
Right click the Sprite
Popup menu – choose edit
Use this tool
uses the rotation point as the reference. All motion
commands do!!
Important when Mario &
Gremlin touch.

55. Review: Today How to get help Boolean Operations
Introducing Project #1
How to “design” before you “code”
Adding and rotating a Sprite

56. What you’ve learned SNAP IDE:
How to login  userid = firstNamelastName pwd = 89oijf8
How to select the desired palette of instructions
What is the “Script Area”
What is the “Stage” area
How to make a “comment” and attach to an instruction lego
How to start  Blue button provides more blocks/instructions
How to get “help”  right click on a lego block – choose help
How to rotate a Sprite
How to create a new Sprite  click turtle sprite, drag image into costume area
How Boolean expressions work and where they are used

57. Reminders Read Chapter 1. Quiz in two weeks Test on Monday, Aug 31
on computers, abstraction, & SNAP!

58. Looking ahead … Monday Tues / Weds Thurs/Fri TODAY 8/24 8/25-26
8/27-28
BACK TO SCHOOL NIGHT
8/31
TEST #1
9/1-2
QUIZ #1
9/3-4
LABOR DAY – NO SCHOOL
9/8-9
PROJECT #1 DUE
9/10-11
Start Unit 2