+ * Based on the Basic game of Kinema here + * https://github.com/coding-horror/basic-computer-games/blob/main/52%20Kinema/kinema.bas + *
+ * Note: The idea was to create a version of the 1970's Basic game in Java, without introducing + * new features - no additional text, error checking, etc has been added. + */ +public class Kinema { + + // Used for keyboard input + private final Scanner kbScanner; + + private enum GAME_STATE { + STARTUP, + INIT, + HOW_HIGH, + SECONDS_TILL_IT_RETURNS, + ITS_VELOCITY, + RESULTS, + GAME_OVER + } + + // Current game state + private GAME_STATE gameState; + + private int numberAnswersCorrect; + + // How many meters per second a ball is thrown + private int velocity; + + public Kinema() { + kbScanner = new Scanner(System.in); + + gameState = GAME_STATE.STARTUP; + } + + /** + * Main game loop + */ + public void play() { + + double playerAnswer; + double correctAnswer; + do { + switch (gameState) { + + case STARTUP: + intro(); + gameState = GAME_STATE.INIT; + break; + + case INIT: + numberAnswersCorrect = 0; + + // calculate a random velocity for the player to use in the calculations + velocity = 5 + (int) (35 * Math.random()); + System.out.println("A BALL IS THROWN UPWARDS AT " + velocity + " METERS PER SECOND."); + gameState = GAME_STATE.HOW_HIGH; + break; + + case HOW_HIGH: + + playerAnswer = displayTextAndGetNumber("HOW HIGH WILL IT GO (IN METERS)? "); + + // Calculate the correct answer to how high it will go + correctAnswer = 0.05 * Math.pow(velocity, 2); + if (calculate(playerAnswer, correctAnswer)) { + numberAnswersCorrect++; + } + gameState = GAME_STATE.ITS_VELOCITY; + break; + + case ITS_VELOCITY: + + playerAnswer = displayTextAndGetNumber("HOW LONG UNTIL IT RETURNS (IN SECONDS)? "); + + // Calculate current Answer for how long until it returns to the ground in seconds + correctAnswer = (double) velocity / 5; + if (calculate(playerAnswer, correctAnswer)) { + numberAnswersCorrect++; + } + gameState = GAME_STATE.SECONDS_TILL_IT_RETURNS; + break; + + case SECONDS_TILL_IT_RETURNS: + + // Calculate random number of seconds for 3rd question + double seconds = 1 + (Math.random() * (2 * velocity)) / 10; + + // Round to one decimal place. + double scale = Math.pow(10, 1); + seconds = Math.round(seconds * scale) / scale; + + playerAnswer = displayTextAndGetNumber("WHAT WILL ITS VELOCITY BE AFTER " + seconds + " SECONDS? "); + + // Calculate the velocity after the given number of seconds + correctAnswer = velocity - (10 * seconds); + if (calculate(playerAnswer, correctAnswer)) { + numberAnswersCorrect++; + } + gameState = GAME_STATE.RESULTS; + break; + + case RESULTS: + System.out.println(numberAnswersCorrect + " RIGHT OUT OF 3"); + if (numberAnswersCorrect > 1) { + System.out.println(" NOT BAD."); + } + gameState = GAME_STATE.STARTUP; + break; + } + } while (gameState != GAME_STATE.GAME_OVER); + } + + private void intro() { + System.out.println(simulateTabs(33) + "KINEMA"); + System.out.println(simulateTabs(15) + "CREATIVE COMPUTING MORRISTOWN, NEW JERSEY"); + System.out.println(); + } + + private boolean calculate(double playerAnswer, double correctAnswer) { + + boolean gotItRight = false; + + if (Math.abs((playerAnswer - correctAnswer) / correctAnswer) < 0.15) { + System.out.println("CLOSE ENOUGH"); + gotItRight = true; + } else { + System.out.println("NOT EVEN CLOSE"); + } + System.out.println("CORRECT ANSWER IS " + correctAnswer); + System.out.println(); + + return gotItRight; + } + + /* + * Print a message on the screen, then accept input from Keyboard. + * Converts input to a Double + * + * @param text message to be displayed on screen. + * @return what was typed by the player. + */ + private double displayTextAndGetNumber(String text) { + return Double.parseDouble(displayTextAndGetInput(text)); + } + + /* + * Print a message on the screen, then accept input from Keyboard. + * + * @param text message to be displayed on screen. + * @return what was typed by the player. + */ + private String displayTextAndGetInput(String text) { + System.out.print(text); + return kbScanner.next(); + } + + /** + * Simulate the old basic tab(xx) command which indented text by xx spaces. + * + * @param spaces number of spaces required + * @return String with number of spaces + */ + private String simulateTabs(int spaces) { + char[] spacesTemp = new char[spaces]; + Arrays.fill(spacesTemp, ' '); + return new String(spacesTemp); + } + +} diff --git a/52 Kinema/java/src/KinemaGame.java b/52 Kinema/java/src/KinemaGame.java new file mode 100644 index 00000000..b84d0019 --- /dev/null +++ b/52 Kinema/java/src/KinemaGame.java @@ -0,0 +1,7 @@ +public class KinemaGame { + public static void main(String[] args) { + + Kinema kinema = new Kinema(); + kinema.play(); + } +}