Ucigame - Gallery - BounceHouse

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Your browser cannot show Java applets. BounceHouse shows off Ucigame's "pixel perfect" collision detection. (If you don't specify pixel perfect, then collision detection is based on the entire rectangular sprite, which in the case of the big X has quite a different shape.) Use the arrow keys to accelerate the spaceship in any direction.

Press the Space key to toggle the spaceship's behavior when it collides with an edge or the big X: it can bounce or stop.

The spaceship's "eyes" turn red briefly when it bumps against the big X or the side of the window. The red "eyes" (see images/et-red-eyes.png) are pinned onto the spaceship sprite, and are normally hidden (because of spaceshipBumped.hide()). When a collision is detected, spaceshipBumped.show() is called, so they appear on top of the usual green "eyes." At timer named "TurnOffBumpedIndicator" is created, which causes TurnOffBumpedIndicatorTimer() to be invoked every 200 milliseconds. But since that method turns itself off, it is only called once, and the eyes are set back to green by hiding the pinned sprite.

BounceHouse.java 
import ucigame.*;

public class BounceHouse extends Ucigame
{
    Sprite bigX;
    Sprite spaceship;
    Sprite spaceshipBumped;
    int howManyFramesToShowInstructions = 120;
    int currFrame = 0;
    boolean bounce = true;

    public void setup()
    {
        window.size(250, 250);
        window.title("Bounce House");
        framerate(30);
        window.showFPS();

        canvas.background(128, 0, 0);

        bigX = makeSprite(getImage("images/bigX.png", 255));
        spaceship = makeSprite(getImage("images/et.png", 255));
        spaceshipBumped = makeSprite(getImage("images/et-red-eyes.png", 255));
        spaceship.pin(spaceshipBumped, 12, 18);
        spaceshipBumped.hide();
        keyboard.typematicOff(keyboard.SPACE);

        bigX.position(50, 50);
        spaceship.position(15, 15);
        spaceship.motion(0, 0);

        if (isAvailableFont("Arial"))
            canvas.font("Arial", ITALIC, 15, 255, 255, 0);
    }

    public void draw()
    {
        canvas.clear();

        if (currFrame < howManyFramesToShowInstructions)
        {
            canvas.putText("Space to toggle bouncing/stopping", 10, 220);
            currFrame = currFrame + 1;
        }

        spaceship.move();
        if (bounce)
            spaceship.bounceIfCollidesWith(
                bigX, TOPEDGE, BOTTOMEDGE, LEFTEDGE, RIGHTEDGE, PIXELPERFECT);
        else
            spaceship.stopIfCollidesWith(
                bigX, TOPEDGE, BOTTOMEDGE, LEFTEDGE, RIGHTEDGE, PIXELPERFECT);
        if (spaceship.collided())
        {
            spaceshipBumped.show();
            startTimer("TurnOffBumpedIndicator", 200);
        }

        bigX.draw();
        spaceship.draw();
    }

    public void onKeyPress()
    {
        // Arrow keys accelerate the spaceship
        if (keyboard.isDown(keyboard.UP))
            spaceship.motion(0, -0.1, ADD);
        if (keyboard.isDown(keyboard.DOWN))
            spaceship.motion(0, 0.1, ADD);
        if (keyboard.isDown(keyboard.LEFT))
            spaceship.motion(-0.1, 0, ADD);
        if (keyboard.isDown(keyboard.RIGHT))
            spaceship.motion(0.1, 0, ADD);

        // Space toggles bouncing (typematic is turned off for Space key)
        if (keyboard.key() == keyboard.SPACE)
            bounce = !bounce;
    }

    public void TurnOffBumpedIndicatorTimer()
    {
        spaceshipBumped.hide();
        stopTimer("TurnOffBumpedIndicator");
    }
}