捕获屏幕的 GLSurfaceView 到位图

android java screen-capture glsurfaceview

2022-09-01 04:20:24

我需要能够在某个时刻捕捉到图像。我有以下代码：GLSurfaceView

relative.setDrawingCacheEnabled(true);
screenshot = Bitmap.createBitmap(relative.getDrawingCache());
relative.setDrawingCacheEnabled(false);
Log.v(TAG, "Screenshot height: " + screenshot.getHeight());
image.setImageBitmap(screenshot);

包含在一个中，但我也尝试使用尝试捕获图像。有了这个，我认为屏幕捕获了一个透明的图像，即那里什么都没有。任何帮助将不胜感激。GLSurfaceViewRelativeLayoutGLSurfaceView

答案 1

SurfaceView并在其窗口中打孔以允许显示其表面。换句话说，它们具有透明的区域。GLSurfaceView

因此，您无法通过调用来捕获图像。GLSurfaceView.getDrawingCache()

如果要从中获取图像，则应在中调用。GLSurfaceViewgl.glReadPixels()GLSurfaceView.onDrawFrame()

我修补了方法并将其调用。createBitmapFromGLSurfaceonDrawFrame()

（原始代码可能来自 skuld 的代码。

private Bitmap createBitmapFromGLSurface(int x, int y, int w, int h, GL10 gl)
        throws OutOfMemoryError {
    int bitmapBuffer[] = new int[w * h];
    int bitmapSource[] = new int[w * h];
    IntBuffer intBuffer = IntBuffer.wrap(bitmapBuffer);
    intBuffer.position(0);

    try {
        gl.glReadPixels(x, y, w, h, GL10.GL_RGBA, GL10.GL_UNSIGNED_BYTE, intBuffer);
        int offset1, offset2;
        for (int i = 0; i < h; i++) {
            offset1 = i * w;
            offset2 = (h - i - 1) * w;
            for (int j = 0; j < w; j++) {
                int texturePixel = bitmapBuffer[offset1 + j];
                int blue = (texturePixel >> 16) & 0xff;
                int red = (texturePixel << 16) & 0x00ff0000;
                int pixel = (texturePixel & 0xff00ff00) | red | blue;
                bitmapSource[offset2 + j] = pixel;
            }
        }
    } catch (GLException e) {
        return null;
    }

    return Bitmap.createBitmap(bitmapSource, w, h, Bitmap.Config.ARGB_8888);
}

答案 2

如果您使用的是第三方库，则这是一个完整的解决方案，您只需“传入”布局中定义的GLSurfaceView。你不会在渲染器的onDrawFrame（）上有一个句柄，这可能是一个问题......

为此，您需要将其排队以便GLSurfaceView处理。

private GLSurfaceView glSurfaceView; // findById() in onCreate
private Bitmap snapshotBitmap;

private interface BitmapReadyCallbacks {
    void onBitmapReady(Bitmap bitmap);
}

/* Usage code
   captureBitmap(new BitmapReadyCallbacks() {

        @Override
        public void onBitmapReady(Bitmap bitmap) {
            someImageView.setImageBitmap(bitmap);
        }
   });
*/

// supporting methods
private void captureBitmap(final BitmapReadyCallbacks bitmapReadyCallbacks) {
    glSurfaceView.queueEvent(new Runnable() {
        @Override
        public void run() {
            EGL10 egl = (EGL10) EGLContext.getEGL();
            GL10 gl = (GL10)egl.eglGetCurrentContext().getGL();
            snapshotBitmap = createBitmapFromGLSurface(0, 0, glSurfaceView.getWidth(), glSurfaceView.getHeight(), gl);

            runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    bitmapReadyCallbacks.onBitmapReady(snapshotBitmap);
                }
            });

        }
    });

}

// from other answer in this question
private Bitmap createBitmapFromGLSurface(int x, int y, int w, int h, GL10 gl) {

    int bitmapBuffer[] = new int[w * h];
    int bitmapSource[] = new int[w * h];
    IntBuffer intBuffer = IntBuffer.wrap(bitmapBuffer);
    intBuffer.position(0);

    try {
        gl.glReadPixels(x, y, w, h, GL10.GL_RGBA, GL10.GL_UNSIGNED_BYTE, intBuffer);
        int offset1, offset2;
        for (int i = 0; i < h; i++) {
            offset1 = i * w;
            offset2 = (h - i - 1) * w;
            for (int j = 0; j < w; j++) {
                int texturePixel = bitmapBuffer[offset1 + j];
                int blue = (texturePixel >> 16) & 0xff;
                int red = (texturePixel << 16) & 0x00ff0000;
                int pixel = (texturePixel & 0xff00ff00) | red | blue;
                bitmapSource[offset2 + j] = pixel;
            }
        }
    } catch (GLException e) {
        Log.e(TAG, "createBitmapFromGLSurface: " + e.getMessage(), e);
        return null;
    }

    return Bitmap.createBitmap(bitmapSource, w, h, Config.ARGB_8888);
}