java - 显示图像作为后台处理

Question

我试图在java处理中使用图像作为背景，但是这段代码给了我错误:“文件“cave_entrance.jpg”丢失或无法访问，请确保URL有效或文件已被访问添加到您的草图中并且可读。”

这是我的代码:

public class Main extends PApplet{

    public void setup(){
        size(900,700);
        background(0);
    }// setup

    public void draw(){
        PImage background = loadImage("cave_entrance.jpg");
        background(background);
    }// draw

}// Main

我的文件 Cave_entrance.jpg 位于

Project
    data
        cave_entrance.jpg

Answer 1

来自处理documentation for the dataPath() function :

This function almost certainly does not do the thing you want it to. The data path is handled differently on each platform, and should not be considered a location to write files. It should also not be assumed that this location can be read from or listed. This function is used internally as a possible location for reading files. It's still "public" as a holdover from earlier code.

Libraries should use createInput() to get an InputStream or createOutput() to get an OutputStream. sketchPath() can be used to get a location relative to the sketch. Again, do not use this to get relative locations of files. You'll be disappointed when your app runs on different platforms.

路径包含 bin 目录听起来也很奇怪。我希望草图中的任何路径都相对于 bin 目录，因此您不需要使用绝对路径来进入该目录。

由于您没有使用处理编辑器，因此必须将 data 目录添加到 source 路径中。如果您在 Eclipse 中，只需将 data 目录复制到 src 目录即可完成此操作。这是比手动将文件复制到 bin 目录更好的解决方案，因为 Eclipse 可以(并且将会)在没有警告的情况下删除这些文件。