Why my function is not working as intended?

Programming Questions

derrickdm..

Why my function is not working as intended?

in Programming Questions • 1 years ago

Hello again Processing Forum,

For the past two days, I've been working on one of the questions in my coursework. The question and the incomplete sketch is as follows:

"Develop some aspects of a very simple game, in Processing. The attached is an incomplete version of a game called Breakout....You need to develop the code as discussed below, to make the game work appropriately...You may add variables as necessary, and additional functions if needed...First complete the functions checkBallAgainstBat()...to do what is specified by them."

I have left out some parts of the coursework question which I feel were unnecessary towards addressing the issue. The first part of my task is to complete the function checkBallAgainstBat(). I highlight my attempts to accomplish this in blue.

//Basic Breakout game
//Code from Matthew Yee-King
//brick position
float brickX;
float brickY;
//brick width and height
float brickH;
float brickW;
//ball position
float ballX;
float ballY;
//ball diameter
float ballD;
//ball direction
float ballDx;
float ballDy;
//bat position
float batX;
//bat width
float batW;
float batH;
//bat colour
float batB;
void setup() {
size (500, 500, P2D);
// set sizes of game items
brickW = 100;
brickH = 50;
batW = 100;
batH = 25;
ballD = 25;
batB = 255;
//random brick position
brickX = random(0, width - brickW);
brickY = random(0, height/2);
// bat in the centre
batX = (width/2) - (batW/2);
//ball atop bat
ballX = batX + (batW/2);
ballY = height - batH - (ballD/2);
//ball movement
ballDx = random(-5, 5);
ballDy = -5;
rectMode(CORNER);
ellipseMode(CENTER);
frameRate (12);
}
void draw() {
//check for ball collision
//with top or sides of bat
checkBallAgainstBat();
//check for ball collision with
//left right and top walls
//and bounce
checkBallAgainstWalls();
//check ball against brick
checkBallAgainstBrick();
//move the ball
ballX += ballDx;
ballY += ballDy;
background(0);
//draw the bat
fill(0, 255, 0);
rect(batX, height - batH, batW, batH);
//draw the brick
fill(0, 0, batB);
batB = (batB +10) % 255;
rect(brickX, brickY, brickW, brickH);
//draw the ball
fill(255, 0, 0);
ellipse(ballX, ballY, ballD, ballD);
if (keyCode == 37) { // left cursor key
batX -= 10;
//keep it on the screen
if (batX < 0) {
batX = 0;
}
}
if (keyCode == 39) { //right cursor key
batX += 10;
if (batX > (width - batW)) {
batX = width - batW;
}
}
}
//when they let go of they key, reset the keyCode
void keyReleased() {
keyCode = -1;
}
//this function checks if the ball has hit the top or sides of the bat and
//update its
//direction as appropriate so the ball bounces off the bat
void checkBallAgainstBat(){
if ((ballY + ballD/2 > height - batH) && (ballX >= batX && ballX <= batX + batW)){
ballDy *= -1;
}
if ((ballX + ballD/2 <= batX || ballX - ballD/2 >= batX + batW) && (ballY >= height - batH && ballY <= height)){
ballDx *= -1;
}
}
//this function checks if the ball has hit the brick. It should bounce off
//the brick and return true if so
boolean checkBallAgainstBrick() {
return false;
}
//this function checks if the ball has hit the top, left or right
//walls and update its
//direction as appropriate so the ball bounces off the walls
void checkBallAgainstWalls(){
if (ballX + ballD/2 > width){// right wall
ballDx *= -1;
}
if (ballX - ballD/2 < 0){// left wall
ballDx *= -1;
}
if (ballY - ballD/2 < 0){// top wall
ballDy *= -1;
}
}

My train on thought is if "the edge of the ball" touches the "sides of the bar", the ball's direction should be altered along it's x-axis. However my sketch does not work as what I had originally intended when translated to code.

I'm hoping I can get some detail explanations as to why my approach to the function does not work, and will appreciate if someone can rectified my logic (or the lack there-off) and equip me with new insights so I can tackle the question armed with new knowledge.

questions by a noob 'processor',

derrick.

Replies(1)

PhiLho

Re: Why my function is not working as intended?

1 years ago

" my sketch does not work as what I had originally intended"
Beside a very slow motion due to the frameRate choice, it seems to work OK. If you intended to make it work differently, you should explain what you expected.

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