docs cleanup
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@ -6,7 +6,9 @@ An introduction to graphics for the Block Editor.
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Ensure you have completed the 'Hello, world!' and Loop tutorials and tested them on a simulator or on BBC micro:bit.
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```blocks
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basic.showString("HI!");
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```
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The BBC micro:bit has a grid of 25 LEDs, so we can use these to display images.
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@ -24,9 +26,16 @@ We can also code our bug to plot a point by giving an x (horizontal) and y (vert
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We can also unplot a point (turn the LED off again) using the `unplot` block. So we could create a flashing LED program, using the `pause` block to create a delay.
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```blocks
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basic.forever(() => {
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led.plot(2,2)
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basic.pause(100)
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led.unplot(2,2)
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basic.pause(100)
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})
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```
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We can also use the `clear screen` block to turn off all LEDs.
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We can also use the `basic.clearScreen` block to turn off all LEDs.
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## Tip
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@ -34,26 +43,35 @@ The pause block is in milliseconds, so setting it to 1000 will have a pause of a
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### Devising algorithms for shapes
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An algorithm is a set of steps to follow to solve a problem. We can begin to draw shapes on the BBC micro:bit using an algorithm. For example, we could draw a straight line with this code:
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An algorithm is a set of steps to follow to solve a problem. We can begin to draw shapes on the BBC micro:bit using an algorithm.
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For example, we could draw a straight line with this code:
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```blocks
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for(let i = 0; i <=4; i++) {
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led.plot(i, 0);
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basic.pause(200)
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}
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```
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Our algorithm is: increase **i** by 1 **from 0** to **4**, and **plot** the point **x=i**, **y=0**. The pause block allows this line to be animated (drawn frame by frame).
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Try devising an algorithm for a diagonal line using the code above and the variable **i**. Your code should look like this; as our variable increases, so does the location that the BBC micro:bit is plotting at:
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We can create more complex algorithms for more complex shapes, too. See the [challenges](/lessons/challenges) section for additional graphical challenges and solutions.
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Try devising an algorithm for a diagonal line using the code above and the variable **i**.
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```sim
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basic.forever(() => {
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for(let i = 0; i <=4; i++) {
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led.plot(i, i);
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basic.pause(200)
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}
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basic.clearScreen();
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})
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```
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### Animations
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Animations are changes happening at a certain rate. For example, we could add the `delay` block from the **Basic** drawer with our square algorithm – this will slowly draw a square (as an animation).
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Animations are changes happening at a certain rate. For example, we could add the `pause` block from the **Basic** drawer with our square algorithm – this will slowly draw a square (as an animation).
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We could create more complex animations, for example we could make our BBC micro:bit display an explosion or fireworks.
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See the [challenges](/lessons/challenges) section for some animation tasks.
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### Image variables
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We can create image variables so we can easily display an image at a later point. For example:
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