AnimateCameraToPosition

// flag to control the animate callback (at completion).
boolean done = false;

private void animateCameraToPosition(LatLng targetLatLng, float targetZoom) {
    CameraPosition currPosition = gMap.getCameraPosition();
    LatLng currLatLng = currPosition.target;

    //meters_per_pixel = 156543.03392 * Math.cos(latLng.lat() * Math.PI / 180) / Math.pow(2, zoom)
    int maxSteps = 500;
    // number of steps between start and midpoint and midpoint and end
    int stepsMid = maxSteps / 2;

    // current zoom
    float initz = currPosition.zoom;
    //TODO maximum zoom (can be computed from overall distance) such that entire path
    //     is visible at midpoint.
    float maxz = 4.0f;
    float finalz = targetZoom;

    CameraUpdateAnimator animator = new CameraUpdateAnimator(gMap, () -> {
        if (!done) {
            gMap.animateCamera(CameraUpdateFactory.
                    zoomTo(targetZoom), 5000, null);
        }
        done = true;

    });

    // loop from start to midpoint

    for (int i = 0; i < stepsMid; i++) {
        // compute interpolated zoom (current --> max) (linear)
        float z = initz - ((initz - maxz) / stepsMid) * i;

        // Compute fractional distance using an exponential function such that for the first
        // half the fraction delta advances slowly and accelerates toward midpoint.
        double ff = (i * (Math.pow(2,maxz) / Math.pow(2,z))) / maxSteps;

        LatLng nextLatLng =
                SphericalUtil.interpolate(currLatLng, targetLatLng, ff);
        animator.add(CameraUpdateFactory.newLatLngZoom(
                nextLatLng, z), false, 0);
    }

    // loop from midpoint to final
    for (int i = 0; i < stepsMid; i++) {
        // compute interpolated zoom (current --> max) (linear)
        float z = maxz + ((finalz - maxz) / stepsMid) * i;
        double ff = (maxSteps - ((i+stepsMid) * ( (Math.pow(2,maxz) / Math.pow(2,z)) ))) / (double)maxSteps;

        LatLng nextLatLng =
                SphericalUtil.interpolate(currLatLng, targetLatLng, ff);

        animator.add(CameraUpdateFactory.newLatLngZoom(
                nextLatLng, z), false, 0);
    }

    animator.add(CameraUpdateFactory.newLatLngZoom(
            targetLatLng, targetZoom), true, 0);

    //

    animator.execute();
}

測試代碼

我用這兩個點(和代碼)測試了從自由女神像到西海岸的一個點：

gMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(40.68924, -74.04454), 13.0f));

new Handler().postDelayed(new Runnable() {
        @Override
        public void run() {
            animateCameraToPosition(new LatLng(33.899832, -118.020450), 13.0f);
        }
    }, 5000);

CameraUpdateAnimator模式

我稍微修改了相機更新動畫師：

public void execute() {
    mMap.setOnCameraIdleListener(this);
    executeNext();
}

private void executeNext() {
    if (cameraUpdates.isEmpty()) {
        mMap.setOnCameraIdleListener(mOnCameraIdleListener);
        mOnCameraIdleListener.onCameraIdle();
    } else {
        final Animation animation = cameraUpdates.remove(0);
        // This optimization is likely unnecessary since I think the
        // postDelayed does the same on a delay of 0 - execute immediately.
        if (animation.mDelay > 0) {
            new Handler().postDelayed(() -> {
                if (animation.mAnimate) {
                    mMap.animateCamera(animation.mCameraUpdate);
                } else {
                    mMap.moveCamera(animation.mCameraUpdate);
                }
            }, animation.mDelay);
        } else {
            if (animation.mAnimate) {
                mMap.animateCamera(animation.mCameraUpdate);
            } else {
                mMap.moveCamera(animation.mCameraUpdate);
            }
        }
    }
}

樣本前

使用

// assume initial (40.68924, -74.04454) z=13.0f
gMap.animateCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(33.899832,-118.020450), 13.0f), 30000, null);

采樣后

這些是從仿真器錄制的。我也側面加載到我的手機(Samsum SM-G960U)上，也有類似的結果(使用1000步0延遲)。

所以我認為這不能完全滿足您的要求：有一些不明確的磁貼&因為它們是從西方傳入的。

自由女神像前往圣地亞哥附近的某個地方

500步0延遲

100步驟0延遲

50步延遲100ms

診斷

在某些方面，深入了解Maps對磁貼做了什么是很有用的。可以通過安裝簡單的UrlTileProvider并記錄請求來提供洞察。此實現將獲取Google Tiles，盡管它們的分辨率通常較低。

要執行此操作，需要執行以下操作：

    // Turn off this base map and install diagnostic tile provider
    gMap.setMapType(GoogleMap.MAP_TYPE_NONE);
    gMap.addTileOverlay(new TileOverlayOptions().tileProvider(new MyTileProvider(256,256)).fadeIn(true));

并定義診斷文件提供程序

public class MyTileProvider extends UrlTileProvider {

    public MyTileProvider(int i, int i1) {
        super(i, i1);
    }

    @Override
    public URL getTileUrl(int x, int y, int zoom) {

        Log.i("tiles","x="+x+" y="+y+" zoom="+zoom);

        try {
            return new URL("http://mt1.google.com/vt/lyrs=m&x="+x+"&y="+y+"&z="+zoom);
        } catch (MalformedURLException e) {
            e.printStackTrace();
            return null;
        }

    }
}

您馬上就會注意到，瓷磚層總是以整數單位(int)定義的?？s放中提供的分數縮放(例如LatLngZoom)嚴格使用內存中的圖像-很好了解?！?/p>

這里有一個完整的示例：

// initial zoom 
x=2411 y=3080 zoom=13
x=2410 y=3080 zoom=13
x=2411 y=3081 zoom=13
x=2410 y=3081 zoom=13
x=2411 y=3079 zoom=13
x=2410 y=3079 zoom=13

和最大值：

x=9 y=12 zoom=5
x=8 y=12 zoom=5
x=9 y=11 zoom=5
x=8 y=11 zoom=5
x=8 y=13 zoom=5
x=9 y=13 zoom=5
x=7 y=12 zoom=5
x=7 y=11 zoom=5
x=7 y=13 zoom=5
x=8 y=10 zoom=5
x=9 y=10 zoom=5
x=7 y=10 zoom=5

下面是每次調用tiler(x軸)時縮放(y軸)的圖表。每個縮放層與所需的IMO計數大致相同。完全變焦顯示的時間是原來的兩倍，因為這是重復的中點。但也有一些異常情況需要解釋(例如110左右)。

這是磁貼提供商記錄的縮放圖表。因此，每個x軸點將代表單個磁貼提取。

這篇關于Google Maps SDK for Android：流暢地將相機設置為新位置的動畫，渲染沿途的所有瓷磚的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，