I'm wondering how to create working blocks in Scratch. I've tried it a few times, and they just seemed to take up space and didn't do anything. Then I see working custom blocks in other people's code and I'm wondering how to do that myself.

Kosi_101O wrote:

I'm wondering how to create working blocks in Scratch. I've tried it a few times, and they just seemed to take up space and didn't do anything. Then I see working custom blocks in other people's code and I'm wondering how to do that myself.

Do you mean these:

block :: custom

or hacked JSON blocks?

Bitebite12 wrote:

Kosi_101O wrote:

I'm wondering how to create working blocks in Scratch. I've tried it a few times, and they just seemed to take up space and didn't do anything. Then I see working custom blocks in other people's code and I'm wondering how to do that myself.

Do you mean these:

block :: custom

or hacked JSON blocks?

.
The My Blocks block.

Well in your editor menu go to my blocks and click the small button called create a block



So you have to put code inside those blocks and then put the block out shown in the my blocks menu

Yeah, but how do you make sure it actually affects the sprite instead of wasting space?

Kosi_101O wrote:

Yeah, but how do you make sure it actually affects the sprite instead of wasting space?

It can be used as a way to repeat a line of code in a separate line without making the base line of code really long and can be used as a way to send messages to other lines of codes in a sprite without having to have the message constantly restart (ex: you have a repeat until script with a message block in it. Without any additional blocks, the message will restart before it can finish where on the other hand, a my block will finish the message and then restart it without skipping anything)

I don't really get it, but thanks anyway

For more information, see this article on the Scratch Wiki.

Kosi_101O wrote:

Yeah, but how do you make sure it actually affects the sprite instead of wasting space?

if you put a block like this one

define 

you can put the blocks that would make the custom block do what you want it to

Kosi_101O wrote:

I don't really get it, but thanks anyway

okay, imagine this code

when green flag clicked
if <(pick random (1) to (10)) = [1]> then 
  repeat (8)
    move (10) steps
    wait (1) seconds
    turn cw (90) degrees
  end
else
  repeat (4)
    move (10) steps
    wait (1) seconds
    turn cw (90) degrees
  end
end

this will make our sprite move in a square, with a 1 in 10 chance of having our sprite move in a square twice
but… its a little repetitive, isnt it? if you wanted to make it play a sound as well when it turns, youd have to add it both times. thats simple enough in this example, but when things get more complicated, it is a very bad idea to repeat yourself like this. missing one instance of some code could break everything, and it will be very annoying

so you use custom blocks instead!

define move in a square
repeat (4)
   move (10) steps
   wait (1) seconds
   turn cw (90) degrees
end

when green flag clicked
if <(pick random (1) to (10)) = [1]> then 
  repeat (2)
    move in a square :: custom
  end
else
  move in a square :: custom
end

whenever you use a custom block, it just acts like youre using the code under its corresponding ‘define’ block. this does the exact same thing as the first script

but its a bit easier to read to the greenflag script this way, isnt it? says exactly what it does. you dont have to think about what happens if you move some steps and then turn, it does what it says, it moves in a square. (again, this is simple enough to be unnecessary for this example, but when things get more complicated this is a very good thing)

and its the same every time!
you want it to play a sound when it turns? easy! you only have to add it once, and it affects it every time no matter how much you do it

define move in a square
repeat (4)
   move (10) steps
   wait (1) seconds
   turn cw (90) degrees
   play sound [... v]
end

but what if we want the 1 in 10 chance to wait 2 seconds between turns, instead of 1? do we have to repeat ourselves like the first script?
no!! because custom blocks can have inputs.

define move in a square, waiting (wait) seconds between turns
repeat (4)
   move (10) steps
   wait (wait :: custom-arg) seconds
   turn cw (90) degrees
end

when green flag clicked
if <(pick random (1) to (10)) = [1]> then 
  repeat (2)
    move in a square, waiting [1] seconds between turns :: custom
  end
else
  move in a square, waiting [1] seconds between turns :: custom
end

theyre like variables. wherever you refer to a custom block input, it gets replaced with whatever you put in the block. this does the same thing as the first one again, but if you want them to wait a different amount of time?

when green flag clicked
if <(pick random (1) to (10)) = [1]> then 
  repeat (2)
    move in a square, waiting [2] seconds between turns :: custom
  end
else
  move in a square, waiting [1] seconds between turns :: custom
end

simple!

also, i dont know how to fit this into that guide, but ‘run without screen refresh’ means things happen immediately. this uses wait blocks, obviously, but even if you remove those from this example script youll notice that it still takes a little bit between turns! running without screen refresh stops it from doing that, so custom blocks also get used if you just need things to happen quickly. in this example it looks like nothing is happening, since it ends how it started, but if you change how much it turns its more noticeable

hope this was helpful, i kinda yapped

Ok thx

KingDrover wrote:

For more information, see this article on the Scratch Wiki.

Ok, I'll check it out.