Created
March 8, 2012 19:45
-
-
Save NickCarneiro/2002945 to your computer and use it in GitHub Desktop.
engine
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
package game; | |
import java.awt.Canvas; | |
import java.awt.Color; | |
import java.awt.Dimension; | |
import java.awt.Graphics2D; | |
import java.awt.event.KeyAdapter; | |
import java.awt.event.KeyEvent; | |
import java.awt.event.WindowAdapter; | |
import java.awt.event.WindowEvent; | |
import java.awt.image.BufferStrategy; | |
import java.util.ArrayList; | |
import javax.swing.JFrame; | |
import javax.swing.JPanel; | |
/** | |
* The main hook of our game. This class with both act as a manager | |
* for the display and central mediator for the game logic. | |
* | |
* Display management will consist of a loop that cycles round all | |
* entities in the game asking them to move and then drawing them | |
* in the appropriate place. With the help of an inner class it | |
* will also allow the player to control the main ship. | |
* | |
* As a mediator it will be informed when entities within our game | |
* detect events (e.g. alient killed, played died) and will take | |
* appropriate game actions. | |
* | |
* | |
*/ | |
public class Engine extends Canvas { | |
private int width = 1024; | |
private int height = 768; | |
private FrameEntity frame; | |
/** The strategey that allows us to use accelerate page flipping */ | |
private BufferStrategy strategy; | |
/** True if the game is currently "running", i.e. the game loop is looping */ | |
private boolean gameRunning = true; | |
/** The list of all the entities that exist in our game */ | |
private ArrayList<Entity> entities = new ArrayList<Entity>(); | |
/** The list of entities that need to be removed from the game this loop */ | |
private ArrayList<Entity> removeList = new ArrayList<Entity>(); | |
private String message = ""; | |
/** True if we're holding up game play until a key has been pressed */ | |
private boolean waitingForKeyPress = true; | |
/** True if the left cursor key is currently pressed */ | |
protected boolean leftPressed = false; | |
protected boolean rightPressed = false; | |
protected boolean upPressed = false; | |
protected boolean downPressed = false; | |
protected boolean spacePressed = false; | |
/** True if game logic needs to be applied this loop, normally as a result of a game event */ | |
private boolean logicRequiredThisLoop = false; | |
private Minigame minigame; | |
/** | |
* Construct our game and set it running. | |
*/ | |
public Engine() { | |
// create a frame to contain our game | |
JFrame container = new JFrame("The Orcs of Rehn"); | |
// get hold the content of the frame and set up the resolution of the game | |
JPanel panel = (JPanel) container.getContentPane(); | |
panel.setPreferredSize(new Dimension(1024,768)); | |
panel.setLayout(null); | |
// setup our canvas size and put it into the content of the frame | |
setBounds(0,0,1024,768); | |
panel.add(this); | |
// Tell AWT not to bother repainting our canvas since we're | |
// going to do that our self in accelerated mode | |
setIgnoreRepaint(true); | |
// finally make the window visible | |
container.pack(); | |
container.setResizable(false); | |
container.setVisible(true); | |
// add a listener to respond to the user closing the window. If they | |
// do we'd like to exit the game | |
container.addWindowListener(new WindowAdapter() { | |
public void windowClosing(WindowEvent e) { | |
System.exit(0); | |
} | |
}); | |
// add a key input system (defined below) to our canvas | |
// so we can respond to key pressed | |
addKeyListener(new KeyInputHandler()); | |
// request the focus so key events come to us | |
requestFocus(); | |
// create the buffering strategy which will allow AWT | |
// to manage our accelerated graphics | |
createBufferStrategy(2); | |
strategy = getBufferStrategy(); | |
// initialise the entities in our game so there's something | |
// to see at startup | |
initEntities(); | |
} | |
/** | |
* Start a fresh game, this should clear out any old data and | |
* create a new set. | |
*/ | |
private void startGame() { | |
// clear out any existing entities and intialise a new set | |
entities.clear(); | |
initEntities(); | |
// blank out any keyboard settings we might currently have | |
leftPressed = false; | |
rightPressed = false; | |
spacePressed = false; | |
upPressed = false; | |
downPressed = false; | |
} | |
/** | |
* Initialise the starting state of the entities (ship and aliens). Each | |
* entitiy will be added to the overall list of entities in the game. | |
*/ | |
private void initEntities() { | |
Entity frame = new FrameEntity(this,"sprites/frame.png", 0, 0); | |
entities.add(frame); | |
//only need to draw this once | |
removeList.add(frame); | |
} | |
/** | |
* The main game loop. This loop is running during all game | |
* play as is responsible for the following activities: | |
* <p> | |
* - Working out the speed of the game loop to update moves | |
* - Moving the game entities | |
* - Drawing the screen contents (entities, text) | |
* - Updating game events | |
* - Checking Input | |
* <p> | |
*/ | |
public void gameLoop() { | |
long lastLoopTime = System.currentTimeMillis(); | |
// keep looping round til the game ends | |
while (gameRunning) { | |
if(minigame != null){ | |
minigame.logic(); | |
if(minigame.complete == true){ | |
if(minigame.result == true){ | |
System.out.println("Minigame won!"); | |
} else { | |
System.out.println("Minigame lost!"); | |
} | |
//exit minigame | |
minigame = null; | |
this.initEntities(); | |
} | |
} else if(spacePressed == true){ | |
minigame = new RunningGame(entities, removeList, this); | |
spacePressed = false; | |
minigame.setup(); | |
} | |
// work out how long its been since the last update, this | |
// will be used to calculate how far the entities should | |
// move this loop | |
long delta = System.currentTimeMillis() - lastLoopTime; | |
lastLoopTime = System.currentTimeMillis(); | |
// Get hold of a graphics context for the accelerated | |
// surface and blank it out | |
Graphics2D g = (Graphics2D) strategy.getDrawGraphics(); | |
// cycle round asking each entity to move itself | |
if (!waitingForKeyPress) { | |
for (int i=0;i<entities.size();i++) { | |
Entity entity = (Entity) entities.get(i); | |
entity.move(delta); | |
} | |
} | |
// cycle round drawing all the entities we have in the game | |
for (int i=0;i<entities.size();i++) { | |
Entity entity = (Entity) entities.get(i); | |
entity.draw(g); | |
} | |
// brute force collisions, compare every entity against | |
// every other entity. If any of them collide notify | |
// both entities that the collision has occured | |
for (int p=0;p<entities.size();p++) { | |
for (int s=p+1;s<entities.size();s++) { | |
Entity me = (Entity) entities.get(p); | |
Entity him = (Entity) entities.get(s); | |
if (me.collidesWith(him)) { | |
me.collidedWith(him); | |
him.collidedWith(me); | |
} | |
} | |
} | |
// remove any entity that has been marked for clear up | |
entities.removeAll(removeList); | |
removeList.clear(); | |
// if a game event has indicated that game logic should | |
// be resolved, cycle round every entity requesting that | |
// their personal logic should be considered. | |
if (logicRequiredThisLoop) { | |
for (int i=0;i<entities.size();i++) { | |
Entity entity = (Entity) entities.get(i); | |
entity.doLogic(); | |
} | |
logicRequiredThisLoop = false; | |
} | |
// if we're waiting for an "any key" press then draw the | |
// current message | |
if (waitingForKeyPress) { | |
g.setColor(Color.white); | |
g.drawString(message,(width-g.getFontMetrics().stringWidth(message))/2,250); | |
g.drawString("Press any key",(width-g.getFontMetrics().stringWidth("Press any key"))/2,300); | |
} | |
// finally, we've completed drawing so clear up the graphics | |
// and flip the buffer over | |
g.dispose(); | |
strategy.show(); | |
// finally pause for a bit. Note: this should run us at about | |
// 100 fps but on windows this might vary each loop due to | |
// a bad implementation of timer | |
try { Thread.sleep(10); } catch (Exception e) {} | |
} | |
} | |
/** | |
* A class to handle keyboard input from the user. The class | |
* handles both dynamic input during game play, i.e. left/right | |
* and shoot, and more static type input (i.e. press any key to | |
* continue) | |
* | |
* This has been implemented as an inner class more through | |
* habbit then anything else. Its perfectly normal to implement | |
* this as seperate class if slight less convienient. | |
* | |
* @author Kevin Glass | |
*/ | |
private class KeyInputHandler extends KeyAdapter { | |
/** The number of key presses we've had while waiting for an "any key" press */ | |
private int pressCount = 1; | |
/** | |
* Notification from AWT that a key has been pressed. Note that | |
* a key being pressed is equal to being pushed down but *NOT* | |
* released. Thats where keyTyped() comes in. | |
* | |
* @param e The details of the key that was pressed | |
*/ | |
public void keyPressed(KeyEvent e) { | |
// if we're waiting for an "any key" typed then we don't | |
// want to do anything with just a "press" | |
if (waitingForKeyPress) { | |
return; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_LEFT) { | |
leftPressed = true; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_RIGHT) { | |
rightPressed = true; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_SPACE) { | |
spacePressed = true; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_UP) { | |
upPressed = true; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_DOWN) { | |
downPressed = true; | |
} | |
} | |
/** | |
* Notification from AWT that a key has been released. | |
* | |
* @param e The details of the key that was released | |
*/ | |
public void keyReleased(KeyEvent e) { | |
// if we're waiting for an "any key" typed then we don't | |
// want to do anything with just a "released" | |
if (waitingForKeyPress) { | |
return; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_LEFT) { | |
leftPressed = false; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_RIGHT) { | |
rightPressed = false; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_SPACE) { | |
spacePressed = false; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_UP) { | |
upPressed = false; | |
} | |
if (e.getKeyCode() == KeyEvent.VK_DOWN) { | |
downPressed = false; | |
} | |
} | |
/** | |
* Notification from AWT that a key has been typed. Note that | |
* typing a key means to both press and then release it. | |
* | |
* @param e The details of the key that was typed. | |
*/ | |
public void keyTyped(KeyEvent e) { | |
// if we're waiting for a "any key" type then | |
// check if we've recieved any recently. We may | |
// have had a keyType() event from the user releasing | |
// the shoot or move keys, hence the use of the "pressCount" | |
// counter. | |
if (waitingForKeyPress) { | |
if (pressCount == 1) { | |
// since we've now recieved our key typed | |
// event we can mark it as such and start | |
// our new game | |
waitingForKeyPress = false; | |
startGame(); | |
pressCount = 0; | |
} else { | |
pressCount++; | |
} | |
} | |
// if we hit escape, then quit the game | |
if (e.getKeyChar() == 27) { | |
System.exit(0); | |
} | |
} | |
} | |
/** | |
* The entry point into the game. We'll simply create an | |
* instance of class which will start the display and game | |
* loop. | |
* | |
* @param argv The arguments that are passed into our game | |
*/ | |
public static void main(String argv[]) { | |
Engine e = new Engine(); | |
// Start the main game loop, note: this method will not | |
// return until the game has finished running. Hence we are | |
// using the actual main thread to run the game. | |
e.gameLoop(); | |
} | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment