Copy a picture of the current screen just before game pause blur it and render to screen in the duration of game pause

Question

I am having trouble implementing a game pause blur screen to render during the gamepause state. I need to take a picture or texture of the current screen i.e gamerunning state, just when the user pauses the screen . Maybe store it to memory, blur it then render it to screen to achieve a nice blur, Gaussian blur effect like they do in popular games like Angry birds.

I tried implementing using a screenshot, but the process of screen capture makes the game freeze for a few seconds which is not nice.

Here is part of my render code

private void updatePlayerForUserInput(float delta)
        {
        if (Gdx.input.isKeyPressed(Keys.P) || pause)
                    {
                        ScreenShotSaver.saveScreenShot();

                        state = State.GAME_PAUSED;

                        if(!DEBUG_MODE)
                        {
                            toggleGestureProcessor(false);

                            setBackgroundTexture(new TextureRegion(applyBlurEffect(Gdx.files.external("madboy/screenshot.png"))));

                            gameScreenGamePauseMenu.sendInMenu();
                        }
                    }
        }

Can someone help implement s screen like this

This is an example of the effect I desire greatly 1 :enter link description here This is another one, similar thing though 2:enter link description here

This is a part of my update logic depending on game state

private void render(float delta)
            {
    switch (state)
            {

            case GAME_READY:
                renderReady();
                break;

            case GAME_RUNNING:
                renderRunning(delta);
                break;

            case GAME_PAUSED:
                renderPaused();
                break;

            case GAME_LEVEL_END:
                renderLevelEnd();
                break;

            case GAME_OVER:
                renderGameOver();
                break;
            }

        }



            private void update(float delta)
            {
                    switch(state)
                    {
                    case GAME_READY:
                        updateReady();
                        break;
                    case GAME_RUNNING:
                        updateRunning(delta);
                        break;
                    case GAME_PAUSED:
                        updatePaused();
                        break;
                    case GAME_LEVEL_END:
                        updateLevelEnd();
                        break;
                    case GAME_OVER:
                        updateGameOver();
                        break;
                    }
            }

Iam using Libgdx library and programming in java

Answer 1

Instead of saving the image of the screenshot to a file, try using the following

TextureRegion(Texture)

Texture(Pixmap)

Pixmap(byte[], int, int)

The byte array in Pixmap's constructor should contain the image bytes, the two ints are offset and length

Example of how you could get the image as bytes:

BufferedImage bufferedImage = new Robot().createScreenCapture(new Rectangle(startX, startY, width, height));
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
ImageIO.write(bufferedImage, format, outputStream);
outputStream.flush();
byte[] data = outputStream.toByteArray();
outputStream.close();

Where format can be any image format in the form of a String (example below):

String format = "png";
String format = "jpg";