还是走合成之后的buf修改

zangcf

// Overrides ConsumerBase:nFrameAvailable(), does not call base class impl.
void FramebufferSurface:nFrameAvailable() {
    sp<GraphicBuffer> buf;
    sp<Fence> acquireFence;
    status_t err = nextBuffer(buf, acquireFence);
    if (err != NO_ERROR) {
        ALOGE("error latching nnext FramebufferSurface buffer: %s (%d)",
                strerror(-err), err);
        return;
    }
    err = mHwc.fbPost(mDisplayType, acquireFence, buf);
    if (err != NO_ERROR) {
        ALOGE("error posting framebuffer: %d", err);
    }
}

status_t err = nextBuffer(buf, acquireFence);
这个就是获得那个buffer。

这个buffer对应的物理地址是多少呢？

zangcf

ANativeWindowBuffer* getNativeBuffer() const;
从GraphicBuffer得到ANativeWindowBuffer

•     ANativeWindow_Buffer outBuffer;  
•     //Surface::SurfaceoutBuffer outBuffer;  
•     surface->lock(&outBuffer,NULL);//获取surface缓冲区的地址  
•     ssize_t bpr = outBuffer.stride * bytesPerPixel(outBuffer.format);  
•     android_memset16((uint16_t*)outBuffer.bits, 0xF800, bpr*outBuffer.height);//往surface缓冲区塞要显示的RGB内容  
  

然后使用上面方法操作buffer