maincanvas.java

J2ME开发的RPG游戏

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;

public class MainCanvas extends Canvas implements Runnable {
	private boolean start;

	private MIDlet midlet;

	private Image screen;

	private Graphics g;

	private int width, height;

	private int key[];

	// ----------------player-----------------------------
	private int px, py = 250;

	private Image pimgL, pimgR;

	private Image fireL, fireR;

	private int pw, ph;

	public static final int LEFT = 0;

	public static final int RIGHT = 1;

	private int dir = RIGHT;

	public static final int STAND = 0;

	public static final int CROUCH = 1;

	public static final int JUMP = 2;

	public static final int RUN = 3;

	public static final int ATTACH = 4;

	public static int state = STAND;

	public int frame = 0;

	private int v0 = 20;

	private int vg = 2;

	/**
	 * 0当前刀光有效，1 x坐标，2 y坐标， 3 时间，4速度 5，杀伤力,6 方向
	 */
	private int[][] fireLR;

	// ---------------------------------------------
	//
	public MainCanvas(MIDlet mid) {
		setFullScreenMode(true);
		width = getWidth();
		height = getHeight();
		midlet = mid;
		start = true;
		key = new int[20];
		screen = Image.createImage(width, height);
		g = screen.getGraphics();
		try {
			pimgL = Image.createImage("/roleLeft.png");
			pimgR = Image.createImage("/roleRight.png");
			fireL = Image.createImage("/roleFireL.png");
			fireR = Image.createImage("/roleFireR.png");
		} catch (Exception e) {
		}
		pw = 55;
		ph = 43;
		fireLR = new int[5][10];
		System.gc();
	}

	public void start() {
		start = true;
		new Thread(this).start();
	}

	public void stop() {
		start = false;
	}

	protected void paint(Graphics arg0) {
		paintScreen();
		arg0.drawImage(screen, 0, 0, Graphics.TOP | Graphics.LEFT);
	}

	private void clear(int color) {
		int old = g.getColor();
		g.setColor(color);
		g.fillRect(0, 0, width, height);
		g.setColor(old);
	}

	// 后台绘制
	private void paintScreen() {
		clear(0xffffff);
		paintPlayer();
		paintFire();
	}

	private void paintFire() {
		for (int i = 0; i < fireLR.length; i++) {
			if (fireLR[i][0] == 1) {
				if (fireLR[i][6] == RIGHT) {
					g.drawImage(fireR, fireLR[i][1], fireLR[i][2], 20);
				} else {
					g.drawImage(fireL, fireLR[i][1] - 28, fireLR[i][2], 20);
				}
			}
		}
	}

	private void paintPlayer() {
		if (dir == RIGHT) {
			g.setClip(px, py, pw, ph);
			g.drawImage(pimgR, px - frame % 3 * pw, py - frame / 3 * ph, 20);
			g.setClip(0, 0, width, height);
		} else if (dir == LEFT) {
			g.setClip(px, py, pw, ph);
			g.drawImage(pimgL, px - frame % 3 * pw, py - frame / 3 * ph, 20);
			g.setClip(0, 0, width, height);
		}
		// switch (state) {
		// case STAND:
		// break;
		// case CROUCH:
		// break;
		// case JUMP:
		// break;
		// case RUN:
		// break;
		// case ATTACH:
		// break;
		// }
	}

	private boolean isHaveKey() {
		for (int i = 0; i < key.length; i++) {
			if (key[i] == 1) {
				return true;
			}
		}
		return false;
	}

	public void keyPressed(int keyCode) {
		switch (keyCode) {
		case -1:
			key[11] = 1;
			break;
		case -2:
			key[12] = 1;
			break;
		case -3:
			key[13] = 1;
			break;
		case -4:
			key[14] = 1;
			break;
		case -5:
			key[15] = 1;
			break;
		case -6:
			key[16] = 1;
			break;
		case -7:
			key[17] = 1;
			break;
		}
	}

	public void keyReleased(int keyCode) {
		switch (keyCode) {
		case -1:
			key[11] = 0;
			break;
		case -2:
			key[12] = 0;
			break;
		case -3:
			key[13] = 0;
			break;
		case -4:
			key[14] = 0;
			break;
		case -5:
			key[15] = 0;
			break;
		case -6:
			key[16] = 0;
			break;
		case -7:
			key[17] = 0;
			break;
		}
	}

	public void run() {
		long st, ed;
		while (start) {
			// game
			st = System.currentTimeMillis();
			input();
			logic();
			repaint();
			Runtime run = Runtime.getRuntime();
			if (run.freeMemory() < 5000) {
				System.gc();
			}
			ed = System.currentTimeMillis();
			try {
				if (ed - st < 80) {
					Thread.sleep(80 - (ed - st));
				}
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
	}

	// 游戏逻辑
	private void logic() {

		fireControl();
		// 玩家控制
		switch (state) {
		case STAND:
			frame = 0;
			break;
		case CROUCH:
			frame = 1;
			break;
		case JUMP:
			frame = 2;
			
			if (frame >= 6 && frame <= 8) {
				frame++;
				if (frame == 8) {
					createFire();
					state = STAND;
				}
			} else {
				frame = 6;
			}
			
			if (dir == LEFT) {
				px -= Data.speed;
			}
			if (dir == RIGHT) {
				px += Data.speed;
			}
			py -= v0;
			v0 -= vg;
			// TODO跳跃碰撞的判断
			if (Math.abs(v0) > 20) {
				state = STAND;
				v0 = 20;
			}
			break;
		case RUN:
			if (dir == LEFT) {
				px -= Data.speed;
			}
			if (dir == RIGHT) {
				px += Data.speed;
			}
			if (frame >= 3 && frame < 5) {
				frame++;
			} else {
				frame = 3;
			}
			break;
		case ATTACH:
			if (frame >= 6 && frame <= 8) {
				frame++;
				if (frame == 8) {
					createFire();
					state = STAND;
				}
			} else {
				frame = 6;
			}

			break;
		}
	}

	private void fireControl() {
		for (int i = 0; i < fireLR.length; i++) {
			if (fireLR[i][0] == 1) {
				if (fireLR[i][6] == LEFT) {
					fireLR[i][1] -= fireLR[i][4];
				} else {
					fireLR[i][1] += fireLR[i][4];
				}
				fireLR[i][3]--;
				if (fireLR[i][3] <= 0) {
					fireLR[i][0] = 0;
				}
			}
		}
	}

	private void createFire() {
		for (int i = 0; i < fireLR.length; i++) {
			if (fireLR[i][0] == 0) {
				fireLR[i][0] = 1;
				fireLR[i][1] = px + 28;
				fireLR[i][2] = py + 10;
				fireLR[i][3] = 20;
				fireLR[i][4] = 5;
				fireLR[i][6] = dir;
				break;
			}
		}
	}

	// 用户输入
	private void input() {
		if (!isHaveKey()) {
			if (state == RUN) {
				state = STAND;
			}
		}
		if (key[11] == 1) {
			switch (state) {
			case STAND:
			case RUN:
				state = JUMP;
				break;
			case CROUCH:
				state = STAND;
				break;
			}
		}
		if (key[12] == 1) {
			if (state == STAND || state == RUN)
				state = CROUCH;
		}

		if (key[13] == 1) {
			dir = LEFT;
			switch (state) {
			case STAND:
			case CROUCH:
				state = RUN;
				break;
			}
		} else if (key[14] == 1) {
			dir = RIGHT;
			switch (state) {
			case STAND:
			case CROUCH:
				state = RUN;
				break;
			}
		}

		if (key[15] == 1) {
			switch (state) {
			case STAND:
			case CROUCH:
				state = ATTACH;
				break;
			}
		}
	}
}