【发布时间】：2020-04-28 23:49:47
【问题描述】：
这是我关于堆栈溢出的第一篇文章，所以如果我违反了有关发帖等的任何规则，我提前道歉。我一直在开发一款小行星-esque 射击游戏，我可以不知道如何在岩石和激光之间进行碰撞检测。
源代码可以在here找到。我不得不对 LevelScreen 的更新方法进行一些更改，因为原始代码依赖于使用 BlueJ IDE。我在这个post 中找到了一个修复程序，并让宇宙飞船和岩石之间的碰撞起作用。
LevelScreen 类
package com.mygdx.game;
import com.badlogic.gdx.Input.Keys;
import com.badlogic.gdx.scenes.scene2d.actions.Actions;
import java.util.ArrayList;
public class LevelScreen extends BaseScreen {
private Spaceship spaceship;
private boolean gameOver;
private boolean rocksNeedRemoved;
private Rock toRemove;
private ArrayList<Rock> rocks;
private ArrayList<Laser> lasers;
public void initialize() {
gameOver = false;
toRemove = null;
rocksNeedRemoved = false;
BaseActor space = new BaseActor(0, 0, mainStage);
space.loadTexture("space.png");
space.setSize(800, 600);
BaseActor.setWorldBounds(space);
spaceship = new Spaceship(400, 300, mainStage);
rocks = new ArrayList<Rock>();
lasers = new ArrayList<Laser>();
rocks.add(new Rock(600, 500, mainStage));
rocks.add(new Rock(600, 300, mainStage));
rocks.add(new Rock(600, 100, mainStage));
rocks.add(new Rock(400, 100, mainStage));
rocks.add(new Rock(200, 100, mainStage));
rocks.add(new Rock(200, 300, mainStage));
rocks.add(new Rock(200, 500, mainStage));
rocks.add(new Rock(400, 500, mainStage));
lasers.add(new Laser(400, 500, mainStage));
}
public void update(float dt) {
//Code from book(Throws class not found error)
/*
for (BaseActor rockActor : BaseActor.getList(mainStage,
"Rock")) {
if (rockActor.overlaps(spaceship)) {
if (spaceship.shieldPower <= 0) {
Explosion boom = new Explosion(0, 0,
mainStage);
boom.centerAtActor(spaceship);
spaceship.remove();
spaceship.setPosition(-1000, -1000);
BaseActor messageLose = new BaseActor(0, 0,
uiStage);
messageLose.loadTexture("message-
lose.png");
messageLose.centerAtPosition(400, 300);
messageLose.setOpacity(0);
messageLose.addAction(Actions.fadeIn(1));
gameOver = true;
}
else {
spaceship.shieldPower -= 34;
Explosion boom = new Explosion(0, 0,
mainStage);
boom.centerAtActor(rockActor);
rockActor.remove();
}
}
for (BaseActor laserActor :
BaseActor.getList(mainStage, "Laser")) {
if (laserActor.overlaps(rockActor)) {
}
Explosion boom = new Explosion(0, 0,
mainStage);
boom.centerAtActor(rockActor);
laserActor.remove();
rockActor.remove();
}
}
if (!gameOver && BaseActor.count(mainStage, "Rock") ==
0) {
BaseActor messageWin = new BaseActor(0, 0,
uiStage);
messageWin.loadTexture("message-win.png");
messageWin.centerAtPosition(400, 300);
messageWin.setOpacity(0);
messageWin.addAction(Actions.fadeIn(1));
gameOver = true;
}
}
*/
// loop I used to get collision working between rocks
and spaceship
for (Rock each : rocks)
if (spaceship.overlaps(each) && !each.crashed &&
spaceship.shieldPower <= 0) {
Explosion boom = new Explosion(0, 0,
mainStage);
Explosion boom2 = new Explosion(0, 0,
mainStage);
boom.centerAtActor(spaceship);
boom2.centerAtActor(each);
spaceship.remove();
spaceship.setPosition(-1000, -1000);
each.crashed = true;
each.clearActions();
each.addAction(Actions.fadeOut(1));
each.addAction(Actions.after(Actions.removeActor()));
rocksNeedRemoved = true;
toRemove = each;
} else if (spaceship.overlaps(each) &&
!each.crashed) {
Explosion boom = new Explosion(0, 0,
mainStage);
boom.centerAtActor(each);
spaceship.shieldPower -= 34;
each.crashed = true;
each.clearActions();
each.addAction(Actions.fadeOut(1));
each.addAction(Actions.after(Actions.removeActor()));
rocksNeedRemoved = true;
toRemove = each;
}
//check for collision between rocks and lasers (Not
working correctly)
for (int i = rocks.size() - 1; i >= 0; i--) {
Rock rock = rocks.get(i);
for (int j = lasers.size() - 1; j >= 0; j--) {
Laser laser = lasers.get(j);
if(rock.getBounds().overlaps(laser.getBounds())) {
Explosion boom = new Explosion(0, 0,
mainStage);
boom.centerAtActor(rock);
rock.crashed = true;
rock.clearActions();
rock.addAction(Actions.fadeOut(1));
rock.addAction(Actions.after(Actions.removeActor()));
rocksNeedRemoved = true;
toRemove = rock;
}
}
}
}
//override default InputProcessor method
public boolean keyDown(int keycode) {
if (keycode == Keys.X)
spaceship.warp();
if (keycode == Keys.SPACE)
spaceship.shoot();
return false;
}
}
宇宙飞船类。
package com.mygdx.game;
import com.badlogic.gdx.scenes.scene2d.Stage;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.Input.Keys;
import com.badlogic.gdx.math.MathUtils;
public class Spaceship extends BaseActor {
private Thrusters thrusters;
private Shield shield;
public int shieldPower;
public Spaceship(float x, float y, Stage s) {
super(x, y, s);
loadTexture("spaceship.png");
setBoundaryPolygon(8);
setAcceleration(100);
setMaxSpeed(100);
setDeceleration(10);
thrusters = new Thrusters(0, 0, s);
addActor(thrusters);
thrusters.setPosition(-thrusters.getWidth(),
getHeight() / 2 - thrusters.getHeight() / 2);
shield = new Shield(0, 0, s);
addActor(shield);
shield.centerAtPosition(getWidth() / 2, getHeight() /
2);
shieldPower = 100;
}
public void act(float dt) {
super.act(dt);
float degreesPerSecond = 160; //rotation speed
if (Gdx.input.isKeyPressed(Keys.LEFT))
rotateBy(degreesPerSecond * dt);
if (Gdx.input.isKeyPressed(Keys.RIGHT))
rotateBy(-degreesPerSecond * dt);
if (Gdx.input.isKeyPressed(Keys.UP)) {
accelerateAtAngle(getRotation());
thrusters.setVisible(true);
}
else {
thrusters.setVisible(false);
}
shield.setOpacity(shieldPower / 100f);
if (shieldPower <= 0)
shield.setVisible(false);
applyPhysics(dt);
wrapAroundWorld();
}
public void warp() {
if(getStage() == null)
return;
Warp warp1 = new Warp(0, 0, this.getStage());
warp1.centerAtActor(this);
setPosition(MathUtils.random(800),
MathUtils.random(600));
Warp warp2 = new Warp(0, 0, this.getStage());
warp2.centerAtActor(this);
}
public void shoot() {
if (getStage() == null)
return;
Laser laser = new Laser(0, 0, this.getStage());
laser.centerAtActor(this);
laser.setRotation(this.getRotation());
laser.setMotionAngle(this.getRotation());
}
}
激光类。
package com.mygdx.game;
import com.badlogic.gdx.math.Rectangle;
import com.badlogic.gdx.scenes.scene2d.Stage;
import com.badlogic.gdx.scenes.scene2d.Action;
import com.badlogic.gdx.scenes.scene2d.actions.Actions;
public class Laser extends BaseActor {
Rectangle bounds;
public Laser(float x, float y, Stage s) {
super(x, y, s);
bounds = new Rectangle((int)getX(), (int)getY(),
(int)getWidth(), (int)getHeight());
loadTexture("laser.png");
addAction(Actions.delay(1));
addAction(Actions.after(Actions.fadeOut(0.5f)));
addAction(Actions.after(Actions.removeActor()));
setSpeed(400);
setMaxSpeed(400);
setDeceleration(0);
}
public void act(float dt) {
super.act(dt);
applyPhysics(dt);
wrapAroundWorld();
}
public Rectangle getBounds() {
return bounds;
}
private void setXY(float pX,float pY) {
setPosition(pX, pY);
bounds.setX((int)pX);
bounds.setY((int)pY);
}
}
摇滚类
package com.mygdx.game;
import com.badlogic.gdx.math.Rectangle;
import com.badlogic.gdx.scenes.scene2d.Stage;
import com.badlogic.gdx.scenes.scene2d.Action;
import com.badlogic.gdx.scenes.scene2d.actions.Actions;
import com.badlogic.gdx.math.MathUtils;
import com.mygdx.game.BaseActor;
public class Rock extends BaseActor {
public boolean crashed;
Rectangle bounds;
public Rock(float x, float y, Stage s) {
super(x, y, s);
bounds = new Rectangle((int)getX(), (int)getY(),
(int)getWidth(), (int)getHeight());
loadTexture("rock.png");
float random = MathUtils.random(30);
addAction(Actions.forever(Actions.rotateBy(30 + random,
1)));
setSpeed(50 + random);
setMaxSpeed(50 + random);
setDeceleration(0);
setMotionAngle(MathUtils.random(360));
crashed = false;
}
public void act(float dt) {
super.act(dt);
applyPhysics(dt);
wrapAroundWorld();
}
public boolean isCrashed() {
return crashed;
}
public void crashed() {
crashed = true;
clearActions();
addAction(Actions.fadeOut(1));
addAction(Actions.after(Actions.removeActor()));
}
public Rectangle getBounds() {
return bounds;
}
private void setXY(float pX,float pY) {
setPosition(pX, pY);
bounds.setX((int)pX);
bounds.setY((int)pY);
}
}
BaseActor 类中的边界和重叠方法
public void setBoundaryPolygon(int numSides) {
float w = getWidth();
float h = getHeight();
float[] vertices = new float[2 * numSides];
for(int i = 0; i < numSides; i ++) {
float angle = i * 6.28f / numSides;
//x coordinate
vertices[2 * i] = w / 2 * MathUtils.cos(angle) + w / 2;
//y coordinate
vertices[2 * i + 1] = h / 2 * MathUtils.sin(angle) + h / 2;
}
boundaryPolygon = new Polygon(vertices);
}
public Polygon getBoundaryPolygon() {
boundaryPolygon.setPosition(getX(), getY());
boundaryPolygon.setOrigin(getOriginX(), getOriginY());
boundaryPolygon.setRotation(getRotation());
boundaryPolygon.setScale(getScaleX(), getScaleY());
return boundaryPolygon;
}
public boolean overlaps(BaseActor other) {
Polygon poly1 = this.getBoundaryPolygon();
Polygon poly2 = other.getBoundaryPolygon();
//initial text to improve performance
if(!poly1.getBoundingRectangle().overlaps(poly2.getBoundingRectangle()))
return false;
return Intersector.overlapConvexPolygons(poly1, poly2);
}
所以我想真正的问题是如何检查岩石 ArrayList 和玩家发射的激光之间的碰撞？在这一点上，我只想完成游戏，即使它没有使用最佳实践。我尝试使用here 描述的方法，没有收到任何错误，但激光和岩石之间也没有碰撞。即使我手动将激光添加到激光 ArrayList。我发现的最后一个post 让我相信我需要像 getAllLasers() 这样的东西，但我不能 100% 确定如何去做。只学习 Box2D 或 Quadtree 会更容易吗？
我意识到这是一个复杂的问题，并提前感谢您抽出宝贵时间阅读它。我很乐意提供您需要的更多信息。
【问题讨论】：
-
这段代码很难读完，请阅读此“create a Minimal, Reproducible Example”，然后尝试再次询问您遇到的问题。
-
“无法正常工作”是什么意思？它是如何工作的，你期望它如何工作？还有什么理由在更新
bounds时将floats转换为ints？rock.getBounds().overlaps(laser.getBounds())应该可以正常工作。如果Rock或Laser被缩放或旋转，你应该相应地更新你的边界 -
我正在尝试做的就是移除一块被激光击中的石头。我摆脱了铸造的整数，它的工作原理是一样的。我想知道激光是否没有被添加到阵列列表中？即使我停止岩石的旋转和运动，它们与激光之间也不会发生碰撞。我将接受上述建议，并以更合适的方式重新询问更多相关信息。谢谢
-
您的代码太长，无法阅读。我猜你的
Rectangles 不是他们应该在的地方。只需在Laser和Rock上覆盖drawDebug方法并在那里绘制它们的bounds，参见示例ibb.co/jDTYtyv。然后启动游戏，看看Rectangles 是否与actor一起绘制。 -
非常感谢您的帮助！
bounds.set(getX(), getY(), getWidth(), getHeight());是我所缺少的。之后，我只需将激光添加到拍摄方法中的数组列表中，一切正常。
标签： java arraylist libgdx collision-detection game-development