Question

我正在尝试为暂停菜单创建背景效果like this。我目前的想法是暂停屏幕截图，保存，打开它，高斯模糊它，然后将其渲染到屏幕并在顶部渲染菜单。唯一的问题是我不知道如何有效地保存屏幕截图。

我尝试使用batch.setColor(0,0,0,0.7f);在背景上渲染褪色图像，但它没有给我我想要的模糊效果，而只是我想象的那种色调。

示例/文档非常感谢。

编辑：找到此代码

package com.me.mygdxgame;

import java.awt.Point;
import java.awt.color.ColorSpace;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.ComponentColorModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferByte;
import java.awt.image.PixelInterleavedSampleModel;
import java.awt.image.Raster;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

import com.badlogic.gdx.Application.ApplicationType;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.utils.ScreenUtils;

public class ScreenShot {

    private static final int[] RGBA_OFFSETS = { 0, 1, 2, 3 };
    private static final int[] RGB_OFFSETS = { 0, 1, 2 };

    public static void saveScreenshot(String baseName) throws IOException {
        File createTempFile = File.createTempFile(baseName, ".png");
        saveScreenshot(createTempFile);
    }

    public static void saveScreenshot(File file) throws IOException {
        saveScreenshot(file, false);
    }

    public static void saveScreenshot(File file, boolean hasAlpha) throws IOException {
        if (Gdx.app.getType() == ApplicationType.Android)
            return;

        byte[] screenshotPixels = ScreenUtils.getFrameBufferPixels(true);

        int width = Gdx.graphics.getWidth();
        int height = Gdx.graphics.getHeight();

        saveScreenshot(file, screenshotPixels, width, height, hasAlpha);
    }

    public static void saveScreenshot(File file, byte[] pixels, int width, int height, boolean hasAlpha) throws IOException {
        DataBufferByte dataBuffer = new DataBufferByte(pixels, pixels.length);

        PixelInterleavedSampleModel sampleModel = new PixelInterleavedSampleModel(DataBuffer.TYPE_BYTE, width, height, 4, 4 * width, getOffsets(hasAlpha));

        WritableRaster raster = Raster.createWritableRaster(sampleModel, dataBuffer, new Point(0, 0));

        BufferedImage img = new BufferedImage(getColorModel(hasAlpha), raster, false, null);

        ImageIO.write(img, "png", file);
    }

    private static ColorModel getColorModel(boolean alpha) {
        if (alpha)
            return new ComponentColorModel(ColorSpace.getInstance(ColorSpace.CS_sRGB), new int[] { 8, 8, 8, 8 }, true, false, ComponentColorModel.TRANSLUCENT, DataBuffer.TYPE_BYTE);
        return new ComponentColorModel(ColorSpace.getInstance(ColorSpace.CS_sRGB), new int[] { 8, 8, 8 }, false, false, ComponentColorModel.OPAQUE, DataBuffer.TYPE_BYTE);
    }

    private static int[] getOffsets(boolean alpha) {
        if (alpha)
            return RGBA_OFFSETS;
        return RGB_OFFSETS;
    }

}

但是当我尝试saveScreenshot("output");时，它会给我这个错误（运行桌面版本，如果这有所不同。还没有在Android上测试过）

Exception in thread "LWJGL Application" com.badlogic.gdx.utils.GdxRuntimeException: java.awt.image.RasterFormatException: Incorrect scanline stride: 3200
    at com.badlogic.gdx.backends.lwjgl.LwjglApplication$1.run(LwjglApplication.java:111)
Caused by: java.awt.image.RasterFormatException: Incorrect scanline stride: 3200

错误行： ImageIO.write(img, "png", file);

Answer 1

我迟到了，但这正是你要找的：

https://github.com/mattdesl/lwjgl-basics/wiki/ShaderLesson5

使用着色器渲染到场缓冲区对象以创建模糊，然后将其从帧缓冲区绘制到屏幕上。

在LibGDX中模糊屏幕

1 个答案: