Question

我需要能够在特定时刻捕捉GLSurfaceView的图像。我有以下代码：

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

GLSurfaceView包含在RelativeLayout中，但我也尝试使用GLSurfaceView直接尝试捕获图像。有了这个，我认为屏幕捕获透明图像，即没有任何东西。任何帮助将不胜感激。

Answer 1

SurfaceView和GLSurfaceView在他们的窗口打孔，以允许他们的表面显示。换句话说，他们有透明的区域。

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

如果您想从GLSurfaceView获取图片，则应在gl.glReadPixels()中调用GLSurfaceView.onDrawFrame()。

我修补了createBitmapFromGLSurface方法并在onDrawFrame()中调用它。

（原始代码可能来自skuld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);
}

Answer 2

如果您使用的是您刚刚传入的第三方图书馆，那么这是一个完整的解决方案。在布局中定义的GLSurfaceView。你不会对渲染器的onDrawFrame（）有一个句柄，这可能是个问题...

要执行此操作，您需要将其排队以便GLSurfaceView进行处理。

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);
}

Answer 3

注意：在此代码中，当我单击按钮时，它将屏幕截图作为图像并将其保存在SD卡位置。我在if方法中使用了布尔条件和onDraw语句，因为渲染器类可以随时调用onDraw方法，并且没有if此代码可以节省很多存储卡中的图像。

MainActivity类：

protected boolean printOptionEnable = false;

saveImageButton.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {
        Log.v("hari", "pan button clicked");
        isSaveClick = true;
        myRenderer.printOptionEnable = isSaveClick;
    }
});

MyRenderer类：

int width_surface , height_surface ;

@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
    Log.i("JO", "onSurfaceChanged");
    // Adjust the viewport based on geometry changes,
    // such as screen rotation
    GLES20.glViewport(0, 0, width, height);

    float ratio = (float) width / height;

    width_surface =  width ;
    height_surface = height ;
}

@Override
public void onDrawFrame(GL10 gl) {
    try {
        if (printOptionEnable) {
            printOptionEnable = false ;
            Log.i("hari", "printOptionEnable if condition:" + printOptionEnable);
            int w = width_surface ;
            int h = height_surface  ;

            Log.i("hari", "w:"+w+"-----h:"+h);

            int b[]=new int[(int) (w*h)];
            int bt[]=new int[(int) (w*h)];
            IntBuffer buffer=IntBuffer.wrap(b);
            buffer.position(0);
            GLES20.glReadPixels(0, 0, w, h,GLES20.GL_RGBA,GLES20.GL_UNSIGNED_BYTE, buffer);
            for(int i=0; i<h; i++)
            {
                //remember, that OpenGL bitmap is incompatible with Android bitmap
                //and so, some correction need.        
                for(int j=0; j<w; j++)
                {
                    int pix=b[i*w+j];
                    int pb=(pix>>16)&0xff;
                    int pr=(pix<<16)&0x00ff0000;
                    int pix1=(pix&0xff00ff00) | pr | pb;
                    bt[(h-i-1)*w+j]=pix1;
                }
            }           
            Bitmap inBitmap = null ;
            if (inBitmap == null || !inBitmap.isMutable()
                || inBitmap.getWidth() != w || inBitmap.getHeight() != h) {
                inBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
            }
            //Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
            inBitmap.copyPixelsFromBuffer(buffer);
            //return inBitmap ;
            // return Bitmap.createBitmap(bt, w, h, Bitmap.Config.ARGB_8888);
            inBitmap = Bitmap.createBitmap(bt, w, h, Bitmap.Config.ARGB_8888);

            ByteArrayOutputStream bos = new ByteArrayOutputStream(); 
            inBitmap.compress(CompressFormat.JPEG, 90, bos); 
            byte[] bitmapdata = bos.toByteArray();
            ByteArrayInputStream fis = new ByteArrayInputStream(bitmapdata);

            final Calendar c=Calendar.getInstance();
            long mytimestamp=c.getTimeInMillis();
            String timeStamp=String.valueOf(mytimestamp);
            String myfile="hari"+timeStamp+".jpeg";

            dir_image = new File(Environment.getExternalStorageDirectory()+File.separator+
            "printerscreenshots"+File.separator+"image");
            dir_image.mkdirs();

            try {
                File tmpFile = new File(dir_image,myfile); 
                FileOutputStream fos = new FileOutputStream(tmpFile);

                byte[] buf = new byte[1024];
                int len;
                while ((len = fis.read(buf)) > 0) {
                fos.write(buf, 0, len);
            }
            fis.close();
            fos.close();
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

            Log.v("hari", "screenshots:"+dir_image.toString());
        }
    } catch(Exception e) {
        e.printStackTrace();
    }
}

Answer 4

您可以使用GLTextureView扩展TextureView而不是GlsurfaceView来向您显示OpenGL数据。

请参阅：http://stackoverflow.com/questions/12061419/converting-from-glsurfaceview-to-textureview-via-gltextureview

当GLTextureView从TextureView扩展时，它有一个应该有效的getBitmap函数。

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捕获GLSurfaceView的屏幕到位图

4 个答案: