Graphics display system including graphics processor having a register storing a series of vertex data relating to a polygonal line

A graphics display system includes a host processor calculating graphic data and providing the graphic data to a graphics processor, and frame memories which store the graphic pixel data and supply display data to display devices. The graphics display system also includes a first register group which stores the graphics data, a second register group which converts and/or stores the data in the first register group, a pixel generator which generates pixels according to the graphic data in the second register group, and a plotter which writes the pixel data generated in the pixel generator in the frame memories. The second register group fetches the data from the first register group when the host processor issues a command for plotting, holds the data previously written by the host processor. At the same time, when the host processor issues a command for plotting, the specified graphic type is written in the graphic processor as sell as data calculated based on the first and second register groups.