Animated text with schedule. How to opacity and close function?

cocos2d-x C++
1

Greetings.

A background. I want to show text in the game using different animations, kinda the talking boxes of RPG games.

Here is the implementation.

In the header:

void UpdateFunction(float dt);

In the CPP file:
First, I call a function with a schedule, with a timeframe of 0.3 secs:

schedule(schedule_selector(MainMenuScene::UpdateFunction), 0.3);

I create a global variable so I can use it to pass through each letter, without assigning the variable inside the function.

int currentLetter = 0;

Now, the function runs like this:
First, I create the label and put it in a position, then add it to the scene.

Label *set1 = Label::createWithTTF("Welcome home", "Marker Felt.ttf", 100);
set1->setPosition(Point(400, 400));
addChild(set1);

Now, I get each letter of the label, create the animation and apply it to each letter.

auto WChar = (Sprite *)set1->getLetter(currentLetter);
auto jump = JumpBy::create(0.5f, Vec2::ZERO, 60, 1);
WChar->runAction(jump);

Finally, I add one to the global currentLetter.

currentLetter ++;

If you run the code, this is what happens:

  • The text appears on screen.
  • Each letter is animated correctly, but the whole text remains in the background.
  • When the animation ends, (obviously) gives me an error because the ++ of the last letter doesn’t exist.

For this last one, I tried to do this but it didn’t work:

if (currentLetter >= set1->getStringLength())
{
    return;
}

So, what I am looking is:

  • How can I make it so each letter appears one by one, without showing what is the next one? (it might be something to do with the opacity I believe)
  • How can I close the function once it finishes all the letters?

Mainly that.

Thanks everyone for your support.

2

Greetings.

I have been doing my homework. Ok now I am able to make the text appear in the scene, like this:

Label *set1 = Label::createWithTTF("Welcome home", "Marker Felt.ttf", 100);
set1->setPosition(Point(400, 400));
set1->setOpacity(0);
addChild(set1);

auto WChar = (Sprite *)set1->getLetter(currentLetter);
auto jump = JumpBy::create(0.5f, Vec2::ZERO, 60, 1);
auto jump_4ever = RepeatForever::create(jump);
WChar->setOpacity(255);
WChar->runAction(jump);

currentLetter++;

This goes inside the function that the schedule calls.

But still I don’t know how to terminate the function once it finishes reading the text, any hint?

Thanks once again.