我需要能够及时捕捉GLSurfaceView到某个时刻的图像。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 a中RelativeLayout，但我也尝试直接使用GLSurfaceView来尝试捕获图像。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。
SurfaceView并GLSurfaceView在其窗户上打孔以显示其表面。换句话说，它们具有透明区域。
所以你不能通过调用来捕获图像GLSurfaceView.getDrawingCache()。
如果要从中获取图像GLSurfaceView，则应调用gl.glReadPixels()in GLSurfaceView.onDrawFrame()。
我修补createBitmapFromGLSurface了方法并在onDrawFrame().
（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);
}
如果您使用的第三方库只是“传入”布局中定义的 GLSurfaceView，那么这是一个完整的解决方案。您将无法处理渲染器的 onDrawFrame()，这可能是个问题...
为此，您需要将其排队等待 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);
}
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 sdcard 位置。我在方法中使用了布尔条件和if语句onDraw，因为渲染器类可能onDraw随时调用该方法，并且没有if此代码可能会在存储卡中保存大量图像。
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();
}
}
您可以使用 GLTextureView 扩展 TextureView 而不是 GlsurfaceView 来向您显示 OpenGL 数据。
由于 GLTextureView 从 TextureView 扩展，它有一个 getBitmap 函数应该可以工作。
myGlTextureView.getBitmap(int width, int height)