Muffin Catcher III

Review — where we got to 5 min

Last lesson the stall started counting.

• change [score v] by (1) on the caught path.
• change [lives v] by (-1) on the missed path.
• wait until <(lives) = (0)> ends the game and says how you did.

Quick-fire

Every muffin in your stall is worth exactly one point. What does that mean for the player?

Today’s Topic 3 min

• The Sound tab, and choosing a sound from the library
• play sound [Pop v] and play sound [Pop v] until done — and which one a game wants
• Different numbers in change [score v] by (1)
• A falling thing that costs a life if you catch it

Learning outcome

By the end of this lesson you will be able to:

1. Add a sound to a sprite and play it at the right moment.
2. Say why “until done” is wrong inside a falling loop.
3. Give two falling things different values, and make the difference visible.

Learnt — sound, value, and a trap 27 min

Sounds live on a sprite

Every sprite carries its own sounds, in the Sound tab beside Costumes. The cat arrives with Meow. Everything else starts with Pop.

1. Click your muffin sprite, then the Sound tab at the top left.
2. Hover the speaker button at the bottom and pick Choose a Sound.
3. Search for Pop. Click it. It is now on this sprite.
4. Go back to the Code tab and open Sound. Your new sound is in the dropdown.

Two blocks, one important difference

In a falling loop, that difference is the whole game. A muffin running play sound [Bubbles v] until done stops in mid-air for two seconds while the sound plays.

The rule: inside a loop, or in anything the player is watching, use play sound [Pop v]. Save “until done” for music, and for a sprite that has nothing else to do.

Worth more, and harder to get

Making a muffin worth three points needs no new block at all. It is change [score v] by (3) — the same block, a different number.

The design part is harder than the code part. A valuable muffin that is just as easy to catch as the others is not a decision, it is a gift. Make it smaller, or quicker, or make it fall near the edges.

if <touching [Bowl v]?> then
  play sound [Pop v]
  change [score v] by (1)
  delete this clone
end
              

if <touching [Bowl v]?> then
  play sound [Coin v]
  change [score v] by (3)
  delete this clone
end
              

The one you must not catch

Now turn it around. A beetle has got into the stall. Catch it and you lose a life. Let it land and nothing happens.

This is the same falling stack as everything else. Only what it does on the caught path is different, and it has no missed path at all.

when I start as a clone
show
go to x: (pick random (-200) to (200)) y: (170)
repeat (34)
  change y by (-10)
  if <touching [Bowl v]?> then
    play sound [Boing v]
    change [lives v] by (-1)
    delete this clone
  end
end
delete this clone
            

Basic — give the stall a voice 25 min

Open your game from last lesson. Test after every step, with the volume up.

Step 1 — a sound for catching

1. Click the muffin. Open the Sound tab and add Pop.
2. Back in Code, put play sound [Pop v] inside the touching-if, above the score block.
3. Play. Every catch should pop, and nothing should stutter.

Step 2 — a sound for missing

1. Add Squeaks to the same sprite.
2. Put play sound [Squeaks v] below the repeat, next to the lives block.
3. Let one land. You should hear it go.

Step 3 — the valuable muffin

1. Right-click your second muffin sprite and check it has its own falling stack.
2. Change its score block to change [score v] by (3).
3. Add Coin to it and play that instead of Pop.
4. Make it harder: set size to (60) %, and a bigger number in its change y.

Step 4 — the beetle

1. Add the Beetle sprite.
2. Give it the maker stack and the falling stack, the same as the muffin.
3. On its caught path, put play sound [Boing v] and change [lives v] by (-1).
4. Leave its missed path with nothing but the delete.
5. Make it come less often than the muffin — a wait of 3 or 4 seconds.

Step 5 — play it properly

1. Play a full game, to the game over.
2. Did you ever choose to move away from something? If not, the beetle is too rare.
3. Did you ever ignore the cake? If not, it is not valuable enough.

A sound for every moment

Three things happen in your game that the player should be able to hear: a catch, a miss, and the end.

• Three different sounds, one per moment.
• None of them holds the game up.
• You can tell them apart with your eyes shut.

Worth going for

Make one kind of muffins worth a lot more than the others — and make it genuinely harder to get.

• At least two values, and the big one is at least three times the small one.
• The valuable one is harder: smaller, quicker, or falling nearer the edges.
• Its sound is different, so you know what you got without looking at the score.

The thing you must not catch

Put something in your stall that punishes the player for catching it. A beetle, a stone, a chilli. Anything that clearly does not belong.

• Catching it costs a life and makes a bad noise.
• Letting it land costs nothing.
• It looks nothing like the things you want.
• It comes rarely enough that catching one feels like a mistake, not bad luck.

when flag clicked
hide
forever
  wait (4) seconds
  create clone of [myself v]
end

when I start as a clone
show
go to x: (pick random (-200) to (200)) y: (170)
repeat (34)
  change y by (-10)
  if <touching [Bowl v]?> then
    play sound [Boing v]
    change [lives v] by (-1)
    delete this clone
  end
end
delete this clone
            

Play it with your eyes shut

Make a version of your stall that can be played by ear. Music underneath, a sound for every event, and music that tells you when you are in trouble.

• Background music that loops with no gap and no stutter.
• A different sound for a catch, a miss, and the beetle.
• The music gets quieter as lives run out.
• The game still plays exactly as before with the sound off.

when flag clicked
set volume to (100) %
forever
  play sound [Garden v] until done
end

when flag clicked
wait until <(lives) = (1)>
set volume to (30) %
            

Summary 4 min

Everything in your stall now means something different.

1. play sound [Pop v] starts a sound and moves on. play sound [Pop v] until done waits, and freezes anything that is falling.
2. A muffin is worth more because of the number in change [score v] by (1), and it is fair because it is harder to catch.
3. A thing you must not catch is the same stack with a different caught path.

Sound tab

Where a sprite’s own sounds live, beside Costumes. The Stage has one too.

play sound

Starts a sound and carries straight on. The right one for a game.

until done

Holds the script until the sound has finished. Right for music, wrong in a loop.

Value

What one catch is worth. Two kinds with two values give the player a choice.

Next lesson: the finale. It speeds up as you win, it ends on a proper Game Over screen, and it remembers your best.