I understand that the beam is manipulated directly, and that’s what makes it different from raster, but I don’t understand how that would work or why it works and how it knows what order to do things in or why it requires different hardware or anything.
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Classic vector graphics uses a Cathode Ray Tube – an electron beam is controlled by electromagnets onto a phosphorous target. The phosphorous is energized and illuminated, providing the displayed image. Engineers can design such a screen with multiple beams, stronger or weaker beams, different phosphorous coatings, and even multiple phosphorous layers. The effect is the ability to draw multiple lines simultaneously, images that last longer, shorter or longer refresh rates, and even color. Color can also be set with masks and even color changing masks using TFT LCD technology.
There are electronics that control the beam, and those are controlled by an analog input signal. The details of this signal are dependent upon the device, but in my experience with oscilloscopes, you can generate a control signal with some software and the output of your sound card.
These devices are pretty limited in their capability but are desirable in some context, I suppose. Sometimes, you just can’t beat analog. These devices don’t store the image any longer than the phosphorous stays illuminated, so the device driver has to run in a loop to control refresh.
Modern vector graphics are a set of points and strokes with brushes. The image renderer has to follow an ordered set of instructions to generate the image from those instructions. The renderer drives a rasterizer, which is software that populates pixel data in a pixel buffer. The data is sent through a video driver, a layer of the OS, to the video hardware, that sends signals to your modern pixel display device.
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