Software choices?

I'm just starting to consider building a laser cutter. I've negotiated the purchase of a 16 year old machine in broken condition and at this point I'm assuming that I'll rip out and replace the control electronics.
I'm trying to make sure that I fully understand the software and hardware options for driving the machine. As I understand it, there are two fundamental options: I can drive the cutter with a regular PC using software such as EMC or Mach3, or I can use a hardware driver such as the DSP board or RetinaEngrave.
What I don't fully understand is how I go from a document in an image editing, drawing, or CAD program to a physical object.
The RetinaEngrave installs a Windows printer driver and takes care of everything (probably an oversimplification but I believe it's fundamentally correct) for my be allowing me to select Print from the application in which I've created my object.
How does this work for options such as EMC or Mach3 or the DSP board? While I understand that vector graphics can be more or less directly translated to the laser, one of my interests is cutting stencils for SMT soldering.
What software options are available to bridge the gap between my document and doing the cutting? I realize this is probably a rather remedial question in the grand scheme of things, but it's something I want to understand before I dive into this project.
I'm trying to make sure that I fully understand the software and hardware options for driving the machine. As I understand it, there are two fundamental options: I can drive the cutter with a regular PC using software such as EMC or Mach3, or I can use a hardware driver such as the DSP board or RetinaEngrave.
What I don't fully understand is how I go from a document in an image editing, drawing, or CAD program to a physical object.
The RetinaEngrave installs a Windows printer driver and takes care of everything (probably an oversimplification but I believe it's fundamentally correct) for my be allowing me to select Print from the application in which I've created my object.
How does this work for options such as EMC or Mach3 or the DSP board? While I understand that vector graphics can be more or less directly translated to the laser, one of my interests is cutting stencils for SMT soldering.
What software options are available to bridge the gap between my document and doing the cutting? I realize this is probably a rather remedial question in the grand scheme of things, but it's something I want to understand before I dive into this project.