Cocos2d-x V3.0 透明处理 (Video + 3D<NativeActivity>)

1. NativeActivity透明处理

总共有以下两层，下层为Video层(SurfaceView)，上层为3D OpenGL层(View)，Video全屏显示，3D无图形元素的地方透明，即可以看到下层的视频。

1.1 项目中的Cocos2dxActivity.java

其主要功能为：1) 向Activity中增加一个SurfaceView,并使3D OpenGL层(View)位于最上面。

2) 播放视频

其完整原代码如下所示：

package org.cocos2dx.cpp;

import android.app.NativeActivity;
import android.app.Activity;
import android.graphics.PixelFormat;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.view.View.OnClickListener;

import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;

import android.view.ViewGroup;

import java.io.IOException;

public class Cocos2dxActivity extends NativeActivity{
	private static final String TAG="MyGame";
	
    
	private SurfaceView mediaPlayView;
	private SurfaceHolder mediaSurfaceHolder = null;
	
	private MediaPlayer  mediaPlayer;
	
	private boolean isMediaPlay = false;
    

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);

		Log.d(TAG,"onCreate start...");

		mediaPlayView = new SurfaceView(this);
		
    	mediaSurfaceHolder = mediaPlayView.getHolder();
    	mediaSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    	mediaSurfaceHolder.addCallback(new MediaSurfaceHolderCallBack());

		LinearLayout.LayoutParams para = new LinearLayout.LayoutParams(
			                           LinearLayout.LayoutParams.FILL_PARENT,LinearLayout.LayoutParams.FILL_PARENT);
		/*
		LinearLayout.LayoutParams para = new LinearLayout.LayoutParams(
		                         LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);
		                         */

		//this.setContentView(mediaPlayView); // remove old views
		this.addContentView(mediaPlayView,para); // keep old views

		ViewGroup vg = (ViewGroup)mediaPlayView.getParent();
		Log.d(TAG,"child count=" + vg.getChildCount());

		/*
		int count = vg.getChildCount();

		for(int i=0; i<count; i++){
			View view = vg.getChildAt(i);
			Log.d(TAG,"index=" + i +":view = " + view);
		}*/

		View view0 = vg.getChildAt(0);
		if(null != view0)
			view0.bringToFront();
		
		
		
		//For supports translucency
		
		//1.change "attribs" in cocos\2d\platform\android\nativeactivity.cpp
		/*const EGLint attribs[] = {
	            EGL_SURFACE_TYPE,EGL_WINDOW_BIT,EGL_RENDERABLE_TYPE,EGL_OPENGL_ES2_BIT,//EGL_BLUE_SIZE,5,-->delete 
	            //EGL_GREEN_SIZE,6,-->delete 
	            //EGL_RED_SIZE,-->delete 
	            EGL_BUFFER_SIZE,32,//-->new field
	            EGL_DEPTH_SIZE,16,EGL_STENCIL_SIZE,8,EGL_NONE
	    };*/
		
		//2.Set the format of window
		getWindow().setFormat(PixelFormat.TRANSLUCENT);
		
	}
	
	MediaPlayer.OnPreparedListener mPreparedListener = new MediaPlayer.OnPreparedListener() {
		@Override
		public void onPrepared(MediaPlayer mp) {
			Log.d(TAG,"onPrepared...");
			int mVideoWidth = 0;
			int mVideoHeight = 0;
			mVideoWidth = mp.getVideoWidth();
			mVideoHeight = mp.getVideoHeight();
			mediaSurfaceHolder.setFixedSize(mVideoWidth,mVideoHeight);
			
			mp.start();
			
			//Log.d(TAG,"isPlaying: " + mediaPlayer.isPlaying());
			//mediaPlayer.setLooping(true);
			
			isMediaPlay = true;

		}
	};
	
	private MediaPlayer.OnCompletionListener mCompletionListener = new MediaPlayer.OnCompletionListener() {
		public void onCompletion(MediaPlayer mp) {
			Log.d(TAG,"onCompletion...");
			//isMediaPlay = false;
			mp.seekTo(0);
			mp.start();
		}
	};

	
    @Override
	protected void onPause() {
		// TODO Auto-generated method stub
		super.onPause();
	}

	

	private class MediaSurfaceHolderCallBack implements SurfaceHolder.Callback{

		@Override
		public void surfaceChanged(SurfaceHolder holder,int format,int width,int height) {
			Log.d(TAG,"surfaceChanged...,width="+width+",height="+height);
			
		}

		@Override
		public void surfaceCreated(SurfaceHolder holder) {

			Log.d(TAG,"surfaceCreated...");
			
			mediaPlayer = new MediaPlayer();
	    	mediaPlayer.setOnPreparedListener(mPreparedListener);
			mediaPlayer.setOnCompletionListener(mCompletionListener);
			
			try {
				//mediaPlayer.setDataSource("/sdcard/video/aoa.mp4");
				mediaPlayer.setDataSource("/sdcard/NativeMedia.ts");
			} catch (IllegalArgumentException e) {
				e.printStackTrace();
			} catch (IllegalStateException e) {
				e.printStackTrace();
			} catch (IOException e) {
				e.printStackTrace();
			}
			mediaPlayer.setDisplay(mediaSurfaceHolder);
			
			try {
				mediaPlayer.prepareAsync(); 
			} catch (IllegalStateException e) {
				e.printStackTrace();
			} 
		}

		@Override
		public void surfaceDestroyed(SurfaceHolder holder) {
			if( mediaPlayer.isPlaying() ){
				mediaPlayer.stop();
				mediaPlayer.release();
				mediaPlayer = null;
			}

			if( mediaSurfaceHolder != null ){
				mediaSurfaceHolder = null;
			}
		}
    }	
}

1.2 项目中的nativeactivity.cpp

1.2.1 修改EGL属性

其代码变化如下engine_init_display：

#if 0     
    const EGLint attribs[] = {
            EGL_SURFACE_TYPE,EGL_BLUE_SIZE,EGL_GREEN_SIZE,EGL_RED_SIZE,EGL_DEPTH_SIZE,EGL_NONE
    };
#else
    const EGLint attribs[] = {
            EGL_SURFACE_TYPE,-->delete 
            //EGL_GREEN_SIZE,-->delete 
            //EGL_RED_SIZE,-->delete 
            EGL_BUFFER_SIZE,//-->new field
            EGL_DEPTH_SIZE,EGL_NONE
    };
#endif

1.2.2 清除color buffer

在engine_draw_frame中增加一行代码：glClearColor(0.0f,0.0f,0.0f);

static void engine_draw_frame(struct engine* engine) {
    LOG_RENDER_DEBUG("engine_draw_frame(...)");
    pthread_t thisthread = pthread_self();
    LOG_RENDER_DEBUG("pthread_self() = %X",thisthread);

    // add code to clear color buffer for transparency
    glClearColor(0.0f,0.0f);

    if (engine->display == NULL) {
        // No display.
        LOGW("engine_draw_frame : No display.");
        return;
    }

    dispatch_pending_runnables();
    cocos2d::Director::getInstance()->mainLoop();
    LOG_RENDER_DEBUG("engine_draw_frame : just called cocos' mainLoop()");

    /* // Just fill the screen with a color. */
    /* glClearColor(((float)engine->state.x)/engine->width,engine->state.angle,*/
    /*         ((float)engine->state.y)/engine->height,1); */
    /* glClear(GL_COLOR_BUFFER_BIT); */	
	
	if (s_pfEditTextCallback && editboxText)
	{
		s_pfEditTextCallback(editboxText,s_ctx);
		free(editboxText);
		editboxText = NULL;
	}	

    eglSwapBuffers(engine->display,engine->surface);
}