Question

我在调整大小方法中使用以下代码来维护多个屏幕尺寸的宽高比：

@Override
public void resize(int width, int height)
{
    float aspectRatio = (float)width / (float)height;
    float scale = 1f;
    Vector2 crop = new Vector2(0, 0);

    if (aspectRatio > globals.ASPECT_RATIO)
    {
        scale = (float)height / (float)globals.VIRTUAL_HEIGHT;
        crop.x = (width - globals.VIRTUAL_WIDTH * scale) / 2f;
    }
    else if (aspectRatio < globals.ASPECT_RATIO)
    {
        scale = (float)width / (float)globals.VIRTUAL_WIDTH;
        crop.y = (height - globals.VIRTUAL_HEIGHT * scale) / 2f;
    }
    else
    {
        scale = (float)width / (float)globals.VIRTUAL_WIDTH;
    }

    float w = (float)globals.VIRTUAL_WIDTH * scale;
    float h = (float)globals.VIRTUAL_HEIGHT * scale;

    viewport = new Rectangle(crop.x, crop.y, w, h);
}

VIRTUAL_WIDTH，VIRTUAL_HEIGHT和ASPECT_RATIO的设置如下：

public final int VIRTUAL_WIDTH = 800;
public final int VIRTUAL_HEIGHT = 480;
public final float ASPECT_RATIO = (float)VIRTUAL_WIDTH / (float)VIRTUAL_HEIGHT;

这对于在屏幕尺寸变化时保持正确的比例非常有效。但是，camera.uproject（我在所有触摸事件之前调用）无法正常工作 - 当调整大小代码将屏幕大小更改为800x480以外的任何其他值时，触摸位置不正确。

以下是我在create（）方法中设置相机的方法：

camera = new OrthographicCamera(globals.VIRTUAL_WIDTH, globals.VIRTUAL_HEIGHT);
camera.setToOrtho(true, globals.VIRTUAL_WIDTH, globals.VIRTUAL_HEIGHT);

这是我的render（）方法的开始：

camera.update();
Gdx.graphics.getGL20().glViewport((int)viewport.x, (int)viewport.y, 
(int)viewport.width, (int)viewport.height);
Gdx.graphics.getGL20().glClearColor(0, 0, 0, 1);
Gdx.graphics.getGL20().glClear(GL20.GL_COLOR_BUFFER_BIT);

如果我忽略调整大小代码并将glViewport方法调用设置为Gdx.graphics.getWidth()和Gdx.graphics.getHeight()，camera.unproject可以正常工作，但我显然无法保持宽高比。有人有什么想法吗？

以下是我在触摸事件中执行非项目的方法：

private Vector3 touchPos = new Vector3(0, 0, 0);

public boolean touchDown (int x, int y, int pointer, int newParam)
{
    touchPos.x = x;
    touchPos.y = y;
    touchPos.z = 0; 
    camera.unproject(touchPos);

    //touch event handling goes here...
}

更新

我通过实现Stage对象在这方面取得了一些进展，但它仍然没有完美运行。

以下是我现在在创建方法中设置舞台和相机的方法：

stage = new Stage();
camera = new OrthographicCamera(globals.VIRTUAL_WIDTH, globals.VIRTUAL_HEIGHT);
camera.setToOrtho(true, globals.VIRTUAL_WIDTH, globals.VIRTUAL_HEIGHT);
stage.setCamera(camera);

这是我的调整大小代码：

public void resize(int width, int height)
{
    Vector2 size = Scaling.fit.apply(800, 480, width, height);
    int viewportX = (int)(width - size.x) / 2;
    int viewportY = (int)(height - size.y) / 2;
    int viewportWidth = (int)size.x;
    int viewportHeight = (int)size.y;
    Gdx.gl.glViewport(viewportX, viewportY, viewportWidth, viewportHeight);
    stage.setViewport(800, 480, true, viewportX, viewportY, viewportWidth, viewportHeight);
}

这是渲染代码的开始：

stage.getCamera().update();
Gdx.graphics.getGL20().glClearColor(0, 0, 0, 1);
Gdx.graphics.getGL20().glClear(GL20.GL_COLOR_BUFFER_BIT);
spriteBatch.setProjectionMatrix(stage.getCamera().combined);

以下是我处理触摸事件的方式：

private Vector3 touchPos = new Vector3(0, 0, 0);

public boolean touchDown (int x, int y, int pointer, int newParam)
{
    touchPos.x = x;
    touchPos.y = y;
    touchPos.z = 0;
    stage.getCamera().unproject(touchPos);

    //touch event handling goes here...
}

当屏幕处于默认大小和屏幕放大时，此功能现在可用。但是，当屏幕尺寸减小时，屏幕越小，触摸点变得越来越不准确。

Answer 1

管理以找到答案。我只需要使用带有Vector3，viewportX，viewportY，viewportWidth和viewportHeight参数的camera.unproject方法调用。所需的视口参数是由上面显示的调整大小代码计算的。

Answer 2

要解决您的问题，新Stage系统中已经有一个已实施的解决方案。请查看wiki scene2d #viewport。要具有固定的aspec比率，您无需手动调整大小和适合。以下是来自维基的黑棒的示例：

public void resize (int width, int height) {
        Vector2 size = Scaling.fit.apply(800, 480, width, height);
        int viewportX = (int)(width - size.x) / 2;
        int viewportY = (int)(height - size.y) / 2;
        int viewportWidth = (int)size.x;
        int viewportHeight = (int)size.y;
        Gdx.gl.glViewport(viewportX, viewportY, viewportWidth, viewportHeight);
        stage.setViewport(800, 480, true, viewportX, viewportY, viewportWidth, viewportHeight);
}

为什么我的libGDX调整代码会破坏camera.unproject？

2 个答案: