Java 针对x轴移动镜像
我试图实现移动到鼠标被点击的点 但是我对X轴的镜像行为有一个问题。 当我点击顶部->它移动到底部,当我点击底部->它移动到顶部 例如,这里是原始位置 我在屏幕上点击了红十字会的位置。 但它会向下移动(如箭头所示) 有什么问题吗?我想这似乎是运动矢量的结果Java 针对x轴移动镜像,java,math,vector,libgdx,Java,Math,Vector,Libgdx,我试图实现移动到鼠标被点击的点 但是我对X轴的镜像行为有一个问题。 当我点击顶部->它移动到底部,当我点击底部->它移动到顶部 例如,这里是原始位置 我在屏幕上点击了红十字会的位置。 但它会向下移动(如箭头所示) 有什么问题吗?我想这似乎是运动矢量的结果 public class Player { private static final float PLAYER_CIRCLE_RADIUS = 24f; private static final float MOVEMEN
public class Player {
private static final float PLAYER_CIRCLE_RADIUS = 24f;
private static final float MOVEMENT_SPEED = 200f;
private final Circle playerCircle;
private Vector2 direction = new Vector2();
private Vector2 position;
private Vector2 velocity = new Vector2();
private Vector2 movement = new Vector2();
private Vector2 mouseClick = new Vector2();
public Player(float x, float y) {
position = new Vector2(x, y);
playerCircle = new Circle(x, y, PLAYER_CIRCLE_RADIUS);
}
public void draw(ShapeRenderer shapeRenderer) {
shapeRenderer.circle(position.x, position.y, playerCircle.radius);
}
public void update(float delta) {
movement.set(velocity).scl(delta);
if (position.dst2(mouseClick) > movement.len2()) { position.add(movement); }
else { position.set(mouseClick); }
}
public void setDirection(float x, float y) {
mouseClick.set(x, y);
direction.set(mouseClick).sub(position).nor();
velocity.set(direction).scl(MOVEMENT_SPEED);
}
public Vector2 getDirection() {
return direction;
}
public Circle getPlayerCircle() {
return playerCircle;
}
public Vector2 getMouseClick() {
return mouseClick;
}
}
public class GameScreen extends ScreenAdapter {
private static final float WORLD_WIDTH = 640;
private static final float WORLD_HEIGHT = 480;
private ShapeRenderer shapeRenderer;
private Viewport viewport;
private Camera camera;
private Player player;
private Destination dest;
@Override
public void render(float delta) {
clearScreen();
update(delta);
shapeRenderer.setProjectionMatrix(camera.projection);
shapeRenderer.setTransformMatrix(camera.view);
shapeRenderer.begin(ShapeRenderer.ShapeType.Line);
dest.draw(shapeRenderer);
player.draw(shapeRenderer);
shapeRenderer.end();
}
@Override
public void resize(int width, int height) {
viewport.update(width, height);
}
@Override
public void show() {
camera = new OrthographicCamera();
camera.position.set(WORLD_WIDTH / 2, WORLD_HEIGHT / 2, 0);
viewport = new FitViewport(WORLD_WIDTH, WORLD_HEIGHT, camera);
shapeRenderer = new ShapeRenderer();
player = new Player(WORLD_WIDTH / 2, WORLD_HEIGHT / 2);
dest = new Destination();
Gdx.input.setInputProcessor(new InputAdapter() {
@Override
public boolean touchDown(int screenX, int screenY, int pointer, int button) {
dest.setPosition(screenX, screenY);
camera.unproject(new Vector3(screenX, screenY, 0));
player.setDirection(screenX, screenY);
return true;
}
});
}
private void clearScreen() {
Gdx.gl.glClearColor(Color.BLACK.r, Color.BLACK.g, Color.BLACK.b, Color.BLACK.a);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
}
private void update(float delta) {
player.update(delta);
}
}
您所描述的实际上是在Y轴上镜像的。 这种行为的原因很可能是图形矩阵的设置方式使原点位于左下角,Y轴指向上,而gui的原点位于左上角,Y轴指向下。因此,当您获得鼠标位置时,您应该执行以下操作:
actualPosY = screenHeight - mousePosY
这将有效地将鼠标位置转换为绘图空间。您描述的内容实际上在Y轴上镜像。 这种行为的原因很可能是图形矩阵的设置方式使原点位于左下角,Y轴指向上,而gui的原点位于左上角,Y轴指向下。因此,当您获得鼠标位置时,您应该执行以下操作:
actualPosY = screenHeight - mousePosY
这将有效地将鼠标位置转换为绘图空间。我明白了。我忘了UI视图是从上到下的。我想我应该加上向量乘法,而不是原始计算。我明白了。我忘了UI视图是从上到下的。我想我应该增加向量乘法而不是原始计算。