android - GLSurfaceView截图时显示黑屏

Question

为了解决我的问题，我徘徊了七个小时。我创建了一个项目，我在其中使用 GLSurfaceView 在上面设置了一张图片，然后我使用 EffectFactory 类。

但我的问题是，当我用受影响的图像拍摄屏幕截图时，它总是显示为黑屏而不是图像。我知道这可能是因为 SurFaceview。但如果有任何建议可能对我有帮助。

提前致谢。

这是我的代码。

public class EffectsFilterActivity extends Activity implements
    GLSurfaceView.Renderer {

private GLSurfaceView mEffectView;
private int[] mTextures = new int[2];
private EffectContext mEffectContext;
private Effect mEffect;
private TextureRenderer mTexRenderer = new TextureRenderer();
private int mImageWidth;
private int mImageHeight;
private boolean mInitialized = false;
int mCurrentEffect;

public void setCurrentEffect(int effect) {
    mCurrentEffect = effect;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    setContentView(R.layout.main);

    Button b = (Button) findViewById(R.id.button1);
    b.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            Bitmap b = takeScreenshot();
            saveBitmap(b);

        }
    });

    mEffectView = (GLSurfaceView) findViewById(R.id.effectsview);
    mEffectView.setEGLContextClientVersion(2);
    mEffectView.setRenderer(this);
    mEffectView.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
    mCurrentEffect = R.id.none;
}

private void loadTextures() {
    // Generate textures
    GLES20.glGenTextures(2, mTextures, 0);

    // Load input bitmap
    Bitmap bitmap = BitmapFactory.decodeResource(getResources(),
            R.drawable.puppy);
    mImageWidth = bitmap.getWidth();
    mImageHeight = bitmap.getHeight();
    mTexRenderer.updateTextureSize(mImageWidth, mImageHeight);

    // Upload to texture
    GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextures[0]);
    GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);

    // Set texture parameters
    GLToolbox.initTexParams();
}

private void initEffect() {
    EffectFactory effectFactory = mEffectContext.getFactory();
    if (mEffect != null) {
        mEffect.release();
    }
    /**
     * Initialize the correct effect based on the selected menu/action item
     */
    switch (mCurrentEffect) {

    case R.id.none:
        break;

    case R.id.autofix:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_AUTOFIX);
        mEffect.setParameter("scale", 0.5f);
        break;

    case R.id.bw:
        mEffect = effectFactory
                .createEffect(EffectFactory.EFFECT_BLACKWHITE);
        mEffect.setParameter("black", .1f);
        mEffect.setParameter("white", .7f);
        break;

    case R.id.brightness:
        mEffect = effectFactory
                .createEffect(EffectFactory.EFFECT_BRIGHTNESS);
        mEffect.setParameter("brightness", 2.0f);
        break;

    case R.id.contrast:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_CONTRAST);
        mEffect.setParameter("contrast", 1.4f);
        break;

    case R.id.crossprocess:
        mEffect = effectFactory
                .createEffect(EffectFactory.EFFECT_CROSSPROCESS);
        break;

    case R.id.documentary:
        mEffect = effectFactory
                .createEffect(EffectFactory.EFFECT_DOCUMENTARY);
        break;

    case R.id.duotone:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_DUOTONE);
        mEffect.setParameter("first_color", Color.YELLOW);
        mEffect.setParameter("second_color", Color.DKGRAY);
        break;

    case R.id.filllight:
        mEffect = effectFactory
                .createEffect(EffectFactory.EFFECT_FILLLIGHT);
        mEffect.setParameter("strength", .8f);
        break;

    case R.id.fisheye:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_FISHEYE);
        mEffect.setParameter("scale", .5f);
        break;

    case R.id.flipvert:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_FLIP);
        mEffect.setParameter("vertical", true);
        break;

    case R.id.fliphor:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_FLIP);
        mEffect.setParameter("horizontal", true);
        break;

    case R.id.grain:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_GRAIN);
        mEffect.setParameter("strength", 1.0f);
        break;

    case R.id.grayscale:
        mEffect = effectFactory
                .createEffect(EffectFactory.EFFECT_GRAYSCALE);
        break;

    case R.id.lomoish:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_LOMOISH);
        break;

    case R.id.negative:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_NEGATIVE);
        break;

    case R.id.posterize:
        mEffect = effectFactory
                .createEffect(EffectFactory.EFFECT_POSTERIZE);
        break;

    case R.id.rotate:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_ROTATE);
        mEffect.setParameter("angle", 180);
        break;

    case R.id.saturate:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_SATURATE);
        mEffect.setParameter("scale", .5f);
        break;

    case R.id.sepia:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_SEPIA);
        break;

    case R.id.sharpen:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_SHARPEN);
        break;

    case R.id.temperature:
        mEffect = effectFactory
                .createEffect(EffectFactory.EFFECT_TEMPERATURE);
        mEffect.setParameter("scale", .9f);
        break;

    case R.id.tint:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_TINT);
        mEffect.setParameter("tint", Color.MAGENTA);
        break;

    case R.id.vignette:
        mEffect = effectFactory.createEffect(EffectFactory.EFFECT_VIGNETTE);
        mEffect.setParameter("scale", .5f);
        break;

    default:
        break;

    }
}

private void applyEffect() {
    mEffect.apply(mTextures[0], mImageWidth, mImageHeight, mTextures[1]);
}

private void renderResult() {
    if (mCurrentEffect != R.id.none) {
        // if no effect is chosen, just render the original bitmap
        mTexRenderer.renderTexture(mTextures[1]);
    } else {
        // render the result of applyEffect()
        mTexRenderer.renderTexture(mTextures[0]);
    }
}

@Override
public void onDrawFrame(GL10 gl) {
    if (!mInitialized) {
        // Only need to do this once
        mEffectContext = EffectContext.createWithCurrentGlContext();
        mTexRenderer.init();
        loadTextures();
        mInitialized = true;
    }
    if (mCurrentEffect != R.id.none) {
        // if an effect is chosen initialize it and apply it to the texture
        initEffect();
        applyEffect();
    }
    renderResult();
}

@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
    if (mTexRenderer != null) {
        mTexRenderer.updateViewSize(width, height);
    }
}

@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    setCurrentEffect(item.getItemId());
    mEffectView.requestRender();
    return true;
}

public Bitmap takeScreenshot() {

    mEffectView.getRootView();
    mEffectView.setDrawingCacheEnabled(true);
    mEffectView.buildDrawingCache();
    mEffectView.requestRender();
    return mEffectView.getDrawingCache();
}

public void saveBitmap(Bitmap bitmap) {
    File imagePath = new File(Environment.getExternalStorageDirectory()
            + "/Piyush.png");
    FileOutputStream fos;
    try {
        fos = new FileOutputStream(imagePath);
        bitmap.compress(CompressFormat.JPEG, 100, fos);
        fos.flush();
        fos.close();
    } catch (FileNotFoundException e) {
        Log.e("GREC", e.getMessage(), e);
    } catch (IOException e) {
        Log.e("GREC", e.getMessage(), e);
    }
}
  }

GLToolbox.java

 public class GLToolbox {

public static int loadShader(int shaderType, String source) {
    int shader = GLES20.glCreateShader(shaderType);
    if (shader != 0) {
        GLES20.glShaderSource(shader, source);
        GLES20.glCompileShader(shader);
        int[] compiled = new int[1];
        GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
        if (compiled[0] == 0) {
            String info = GLES20.glGetShaderInfoLog(shader);
            GLES20.glDeleteShader(shader);
            shader = 0;
            throw new RuntimeException("Could not compile shader "
                    + shaderType + ":" + info);
        }
    }
    return shader;
}

public static int createProgram(String vertexSource, String fragmentSource) {
    int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
    if (vertexShader == 0) {
        return 0;
    }
    int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
    if (pixelShader == 0) {
        return 0;
    }

    int program = GLES20.glCreateProgram();
    if (program != 0) {
        GLES20.glAttachShader(program, vertexShader);
        checkGlError("glAttachShader");
        GLES20.glAttachShader(program, pixelShader);
        checkGlError("glAttachShader");
        GLES20.glLinkProgram(program);
        int[] linkStatus = new int[1];
        GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
        if (linkStatus[0] != GLES20.GL_TRUE) {
            String info = GLES20.glGetProgramInfoLog(program);
            GLES20.glDeleteProgram(program);
            program = 0;
            throw new RuntimeException("Could not link program: " + info);
        }
    }
    return program;
}

public static void checkGlError(String op) {
    int error;
    while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
        throw new RuntimeException(op + ": glError " + error);
    }
}

public static void initTexParams() {
    GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D,
            GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);
    GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D,
            GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_LINEAR);
    GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S,
            GLES20.GL_CLAMP_TO_EDGE);
    GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T,
            GLES20.GL_CLAMP_TO_EDGE);
}

   }

TextureRenderer.java

public class TextureRenderer {

private int mProgram;
private int mTexSamplerHandle;
private int mTexCoordHandle;
private int mPosCoordHandle;

private FloatBuffer mTexVertices;
private FloatBuffer mPosVertices;

private int mViewWidth;
private int mViewHeight;

private int mTexWidth;
private int mTexHeight;

private static final String VERTEX_SHADER = "attribute vec4 a_position;\n"
        + "attribute vec2 a_texcoord;\n" + "varying vec2 v_texcoord;\n"
        + "void main() {\n" + "  gl_Position = a_position;\n"
        + "  v_texcoord = a_texcoord;\n" + "}\n";

private static final String FRAGMENT_SHADER = "precision mediump float;\n"
        + "uniform sampler2D tex_sampler;\n" + "varying vec2 v_texcoord;\n"
        + "void main() {\n"
        + "  gl_FragColor = texture2D(tex_sampler, v_texcoord);\n" + "}\n";

private static final float[] TEX_VERTICES = { 0.0f, 1.0f, 1.0f, 1.0f, 0.0f,
        0.0f, 1.0f, 0.0f };

private static final float[] POS_VERTICES = { -1.0f, -1.0f, 1.0f, -1.0f,
        -1.0f, 1.0f, 1.0f, 1.0f };

private static final int FLOAT_SIZE_BYTES = 4;

public void init() {
    // Create program
    mProgram = GLToolbox.createProgram(VERTEX_SHADER, FRAGMENT_SHADER);

    // Bind attributes and uniforms
    mTexSamplerHandle = GLES20
            .glGetUniformLocation(mProgram, "tex_sampler");
    mTexCoordHandle = GLES20.glGetAttribLocation(mProgram, "a_texcoord");
    mPosCoordHandle = GLES20.glGetAttribLocation(mProgram, "a_position");

    // Setup coordinate buffers
    mTexVertices = ByteBuffer
            .allocateDirect(TEX_VERTICES.length * FLOAT_SIZE_BYTES)
            .order(ByteOrder.nativeOrder()).asFloatBuffer();
    mTexVertices.put(TEX_VERTICES).position(0);
    mPosVertices = ByteBuffer
            .allocateDirect(POS_VERTICES.length * FLOAT_SIZE_BYTES)
            .order(ByteOrder.nativeOrder()).asFloatBuffer();
    mPosVertices.put(POS_VERTICES).position(0);
}

public void tearDown() {
    GLES20.glDeleteProgram(mProgram);
}

public void updateTextureSize(int texWidth, int texHeight) {
    mTexWidth = texWidth;
    mTexHeight = texHeight;
    computeOutputVertices();
}

public void updateViewSize(int viewWidth, int viewHeight) {
    mViewWidth = viewWidth;
    mViewHeight = viewHeight;
    computeOutputVertices();
}

public void renderTexture(int texId) {
    // Bind default FBO
    GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);

    // Use our shader program
    GLES20.glUseProgram(mProgram);
    GLToolbox.checkGlError("glUseProgram");

    // Set viewport
    GLES20.glViewport(0, 0, mViewWidth, mViewHeight);
    GLToolbox.checkGlError("glViewport");

    // Disable blending
    GLES20.glDisable(GLES20.GL_BLEND);

    // Set the vertex attributes
    GLES20.glVertexAttribPointer(mTexCoordHandle, 2, GLES20.GL_FLOAT,
            false, 0, mTexVertices);
    GLES20.glEnableVertexAttribArray(mTexCoordHandle);
    GLES20.glVertexAttribPointer(mPosCoordHandle, 2, GLES20.GL_FLOAT,
            false, 0, mPosVertices);
    GLES20.glEnableVertexAttribArray(mPosCoordHandle);
    GLToolbox.checkGlError("vertex attribute setup");

    // Set the input texture
    GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
    GLToolbox.checkGlError("glActiveTexture");
    GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texId);
    GLToolbox.checkGlError("glBindTexture");
    GLES20.glUniform1i(mTexSamplerHandle, 0);

    // Draw
    GLES20.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
    GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
    GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
}

private void computeOutputVertices() {
    if (mPosVertices != null) {
        float imgAspectRatio = mTexWidth / (float) mTexHeight;
        float viewAspectRatio = mViewWidth / (float) mViewHeight;
        float relativeAspectRatio = viewAspectRatio / imgAspectRatio;
        float x0, y0, x1, y1;
        if (relativeAspectRatio > 1.0f) {
            x0 = -1.0f / relativeAspectRatio;
            y0 = -1.0f;
            x1 = 1.0f / relativeAspectRatio;
            y1 = 1.0f;
        } else {
            x0 = -1.0f;
            y0 = -relativeAspectRatio;
            x1 = 1.0f;
            y1 = relativeAspectRatio;
        }
        float[] coords = new float[] { x0, y0, x1, y0, x0, y1, x1, y1 };
        mPosVertices.put(coords).position(0);
    }
}
  }

我的 Xml 文件:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:ignore="HardcodedText" >

 <Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="0dp"
    android:layout_weight="0.1"
    android:text="Button" />

 <android.opengl.GLSurfaceView
    android:id="@+id/effectsview"
    android:layout_width="fill_parent"
    android:layout_height="0dp"
    android:layout_weight="0.9" />

</LinearLayout>

Answer 1

试试这个...

private volatile boolean saveFrame;

// called when Capture button is clicked.
public void onClick(View view) {
    saveFrame = true;
    mEffectView.requestRender();
}

@Override
public void onDrawFrame(GL10 gl) {
    if (!mInitialized) {
        // Only need to do this once
        mEffectContext = EffectContext.createWithCurrentGlContext();
        mTexRenderer.init();
        loadTextures();
        mInitialized = true;
    }
    if (mCurrentEffect != NONE) {
        // if an effect is chosen initialize it and apply it to the texture
        initEffect();
        applyEffect();
    }
    renderResult();
    if (saveFrame) {
        saveBitmap(takeScreenshot(gl));
        saveFrame = false;
    }
}

private void saveBitmap(Bitmap bitmap) {
    try {
        FileOutputStream stream = openFileOutput("image.png", MODE_PRIVATE);
        bitmap.compress(CompressFormat.PNG, 100, stream);
        stream.flush();
        stream.close();
        Log.i("TAG", "SAVED");
    } catch (Exception e) {
        Log.e("TAG", e.toString(), e);
    }
}

public Bitmap takeScreenshot(GL10 mGL) {
    final int mWidth = mEffectView.getWidth();
    final int mHeight = mEffectView.getHeight();
    IntBuffer ib = IntBuffer.allocate(mWidth * mHeight);
    IntBuffer ibt = IntBuffer.allocate(mWidth * mHeight);
    mGL.glReadPixels(0, 0, mWidth, mHeight, GL10.GL_RGBA, GL10.GL_UNSIGNED_BYTE, ib);

    // Convert upside down mirror-reversed image to right-side up normal image.
    for (int i = 0; i < mHeight; i++) {
        for (int j = 0; j < mWidth; j++) {
            ibt.put((mHeight - i - 1) * mWidth + j, ib.get(i * mWidth + j));
        }
    }

    Bitmap mBitmap = Bitmap.createBitmap(mWidth, mHeight,Bitmap.Config.ARGB_8888);
    mBitmap.copyPixelsFromBuffer(ibt);
    return mBitmap;
}