94 lines
1.9 KiB
Markdown
94 lines
1.9 KiB
Markdown
# rotation animation quiz answers
|
|
|
|
Learn how to create a rotating image with a while loop.
|
|
|
|
This is the answer key for the [rotation animation quiz](/lessons/rotation-animation/quiz).
|
|
|
|
## 1. What is a " variable"?
|
|
|
|
Answers may vary. A variable is a place where you can store data so that you can use it later in your code.
|
|
|
|
## 2. Write the code to create a ** variable** called `foo` that stores a boolean and initialize it to **false**.
|
|
|
|
|
|
|
|
```blocks
|
|
let rotating = true;
|
|
```
|
|
|
|
## 3. Explain what this line of code does.
|
|
|
|
```blocks
|
|
let rotating = true;
|
|
while (rotating) {
|
|
basic.showLeds(`
|
|
. . . . .
|
|
. . . . .
|
|
. . # . .
|
|
. . . . .
|
|
. . . . .
|
|
`)
|
|
basic.showLeds(`
|
|
. . . . .
|
|
. . . . .
|
|
. . . . .
|
|
. . . . .
|
|
. . . . .
|
|
`)
|
|
}
|
|
|
|
```
|
|
|
|
|
|
|
|
<br/>
|
|
|
|
It is a **while** loop that will be executed only if the ** variable** called `rotating` is **true**.
|
|
|
|
## 4. If the rectangle below represents the BBC micro:bit, shade the areas that will be displayed. Explain why that particular area is shaded.
|
|
|
|
```blocks
|
|
basic.showLeds(`
|
|
. . # . .
|
|
. . # . .
|
|
. . # . .
|
|
. . # . .
|
|
. . # . .
|
|
`)
|
|
basic.showLeds(`
|
|
. . . . .
|
|
. . . . .
|
|
# # # # #
|
|
. . . . .
|
|
. . . . .
|
|
`)
|
|
basic.showLeds(`
|
|
. . . . #
|
|
. . . # .
|
|
. . # . .
|
|
. # . . .
|
|
# . . . .
|
|
`)
|
|
basic.showLeds(`
|
|
. . . . #
|
|
. . . # .
|
|
. . # . .
|
|
. # . . .
|
|
# . . . .
|
|
`)
|
|
|
|
```
|
|
|
|
|
|
|
|
![](/static/mb/lessons/rotation-animation-0.png)
|
|
|
|
![](/static/mb/lessons/rotation-animation-1.png)
|
|
|
|
![](/static/mb/lessons/rotation-animation-2.png)
|
|
|
|
![](/static/mb/lessons/rotation-animation-3.png)
|
|
|
|
Show animation will show a series of image frames on the LED screen, pausing the specified time (400 milliseconds) after each frame
|
|
|