java - 我如何计算这个类的信箱大小？

Question

我为 LibGdx OpenGL 项目编写了以下 Java 类。 无论您如何通过顶部、底部或侧面的信箱调整屏幕大小，相机都会保持屏幕的宽高比。到目前为止，一切顺利。

当我尝试获取鼠标单击的 x、y 坐标，并且该轴涉及信箱时，就会出现问题。 首先是类(class):

public class Camera {

private static float viewportWidth;
private static float viewportHeight;
private static float aspectRatio;
private static float barSize;

/**
  * Creates an orthographic camera where the "play area" has the given viewport size. The viewport will be scaled to maintain the aspect ratio.
  * 
  * @param virtualWidth the width of the game screen in virtual pixels.
  * @param virtualHeight the height of the game screen in virtual pixels.
  * @return the new camera.
  * 
  */

public static OrthographicCamera createCamera(float virtualWidth, float virtualHeight) {

    aspectRatio = virtualWidth / virtualHeight;


    float physicalWidth = Gdx.graphics.getWidth();
    float physicalHeight = Gdx.graphics.getHeight();

    if (physicalWidth / physicalHeight >= aspectRatio) {
//      Letterbox left and right.
         viewportHeight = virtualHeight;
         viewportWidth = viewportHeight * physicalWidth / physicalHeight;
         barSize = ????;
    }
    else {
//      Letterbox above and below.
       viewportWidth = virtualWidth;
       viewportHeight = viewportWidth * physicalHeight / physicalWidth;
       barSize = ????;
    }

    OrthographicCamera cam = new OrthographicCamera(viewportWidth , viewportHeight);
    cam.position.set(virtualWidth / 2, virtualHeight / 2, 0);
    cam.rotate(180, 1, 0, 0);
    cam.update();
    Gdx.app.log("BTLog", "barSize:"+barSize);
    return cam;
}

public static float getViewportWidth() {
    return viewportWidth;
}

public static float getViewportHeight() {
    return viewportHeight;
}
}

当事件发生时，LibGdx 为我提供 x 和 y 坐标，我需要将这些原始坐标转换为相机的比例(虚拟高度和宽度)。

当屏幕被拉伸(stretch)时(根本没有信箱)，可以很容易地使用以下方法获取 x 和 y 坐标:

xRelative = (int) (x / (float)Gdx.graphics.getWidth() * Camera.getViewportWidth());
yRelative = (int) (y / (float)Gdx.graphics.getHeight() * Camera.getViewportHeight());

问题是当信箱发挥作用时，它会偏离该轴的坐标。我知道我需要考虑信箱的宽度，但我花了很长时间才弄清楚如何计算它。

上面有“barSize = ??????;”我的第一直觉是这样做: barSize = 物理高度 - 视口(viewport)高度；//以高度为例

一旦我得到了 barSize，我相当确定我可以使用它来获得正确的数字(例如使用 y 轴):

yRelative = (int) (y / (float)Gdx.graphics.getHeight() * Camera.getViewportHeight() - Camera.getBarSize());

但是数字不匹配。任何建议将不胜感激!

Answer 1

Ray ray = camera.getPickRay(x, y);
System.out.println(ray.origin.x);
System.out.println(ray.origin.y);