dinorunner.prcs

// We want to do a "runner" game.
// (Dinosaur browser game)
// First, let's decide how many objects (cacti) can appear at a time.

int n = 8; // 4 cacti at a time...

size(800, 400);

// horizontal coordinate, width, and height of each cactus
double[] x = new double[n], w = new double[n], h = new double[n];

// dino's y coordinate (distance from ground) and speed
double y = 0, dy = 0;
// dino constants
int dinoX = 20, dinoW = 20, dinoH = 40;
// where is the ground?
int groundY = 350;

void mousePressed() {
    // Make dino jump
    dy = 10;
}

void draw() {
    background(rgb(255,255,255));
    stroke(rgb(0,0,0)); // black line for ground
    line(0,groundY, width, groundY);
    noStroke();
    fill(rgb(151,85,53)); // dino brown
    rect(dinoX, groundY - y - dinoH, dinoW, dinoH);
    y = y + dy;
    if (y > 0) {
        // dino in air
        dy = dy - .5; // gravity
    } else {
        // dino not in the air
        y = 0; // can't go below ground
        dy = 0; // don't move if at 0
    }
    
    // Maybe a cactus appears?
    if (random(0, 1) < .02) { // 1% chance every frame
        // Put a new cactus into the cactus array.. but where?
        // Find a zero width cactus...
        for (int i = 0; i < n; i++) {
            if (w[i] == 0) {
                // index i has zero width
                // let's replace it with a real cactus
                w[i] = random(20, 40);
                h[i] = random(40, 80);
                x[i] = width; // start at right side
                break; // get out of the loop - only one cactus at a time!
            }
        }
    }
    
    // Draw and move the cactuses!
    fill(rgb(94,215,64)); // cactus green
    for (int i = 0; i < n; i++) {
        if (w[i] > 0) {
            // Is the cactus touching the dino?
            // Does the cactus rectangle intersect the dino rectangle
            // If the left edge of the cactus is before the right edge of the dino
            // And the right edge of the cactus is after the left edge of the dino
            // And the top edge of the cactus is above the bottom edge of the dino
            if (x[i] < dinoX + dinoW && x[i] + w[i] > dinoX && h[i] > y) {
                background(rgb(255,0,0));
            }
            // Draw the real cactus
            rect(x[i], groundY-h[i], w[i], h[i]);
            // Move the cactus
            x[i] = x[i] - 5;
            // If the cactus is off the left side of the screen...
            if (x[i] + w[i] < 0) {
                w[i] = 0; // zero width cactuses don't exist!
            }
        }
    }
    
}