Step 1: Things you'll need
-Eagle3D -- This will generate the file used by POV-Ray
-POV-Ray -- This will render the final image of the PCB.
Step 2: Create a POV-Ray file
Step 3: Let POV-Ray include Eagle3D files
Eagle3D uses special #include files when it is scripting, and you need to give these files to POV-Ray for your image to render. First, go into your Eagle3D program directory. Find the folder named POV-Ray, and copy the files to the "include" folder in the POV-Ray root directory. (Picture 1)
To make life a bit easier, you could also specify the directory where the original Eagle3D include files are located. To do this, open your POV-Ray root directory, open the "renderer" folder, and edit the POV-Ray.ini file. Add the following line to the base of the file:
Of course, you should change the "C:\Program Files\Eagle3D" to where ever the root directory of Eagle3D is located. (Picture 2)
Step 4: Generate the image!
Step 5: Other ideas
Eagle3D only includes a number of parts, and you can expand your library. Here is a link to a tutorial showing you how to create your own parts.