beginRaw and endRaw example code does not work

Issue description

The example code for beginRaw and endRaw does not work. Those functions are not available for the default renderer.

I'm happy to make a PR for this but someone needs to tell me which file to edit. Is the reference documentation generated from XML files or is that old code and data?

URL(s) of affected page(s)

https://processing.org/reference/beginRaw_.html
https://processing.org/reference/endRaw_.html

Proposed fix

Add P2D to the setup() function like this:

void setup() {
   size(400, 400, P2D);
   beginRaw(PDF, "raw.pdf");
}

从受影响的参考页面 beginRaw_.html 和 endRaw_.html 开始，追溯到这些页面示例的源文件。确认 Processing 网站如何存储参考文档，然后更新这两个示例以包含 P2D，并验证显示的代码与提议的可用设置相匹配。