JPS6114529B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a graphic printer device using scan conversion for large screens, for example, and to significantly compressing the memory used.

[Prior art and problems to be solved by the invention]

2. Description of the Related Art Some apparatuses that record images with high precision and high speed use means for converting the coordinates of vector information provided from an electronic computer to generate a scanning pattern signal. In this system, all vector data for one screen is first stored in a vector memory by a computer. Thereafter, the scan conversion circuit reads out vectors one by one from the vector memory. One screen is divided into many partial areas.
Then, only the portion belonging to that partial area is selectively written into one of the plurality of pattern memories that are cyclically switched. After this selective writing is performed for all vectors on one screen, the video signal obtained by reading out the contents of the pattern memory in a raster scanning manner is sent to the printer section and stored therein. By repeating the scan conversion for one partial area by the number of partial areas obtained by dividing the entire screen, the scan conversion of the entire screen, that is, the desired recording is completed. Writing and reading are alternately and cyclically performed on the plurality of pattern memories.

However, in the case of the above-mentioned method, when the screen becomes very large, in order to read the figure, it is necessary to read the entire screen data, and the proportion of time required for vectors that do not belong to the relevant partial area is The problem is that the conversion efficiency deteriorates, and the capacity of a high-speed and expensive vector memory for storing vector data of the entire screen increases proportionally.

SUMMARY OF THE INVENTION In view of this problem, it is an object of the present invention to provide a graphic printer using a scan conversion method that can be constructed at low cost and without reducing the recording speed even when the screen is large.

[Means for solving problems]

In the present invention, one screen of vector data sent from a computer is divided into small partial areas, and a video signal based on the divided vector information is scan-converted via a plurality of pattern memories to print one screen of figures. In the graphic printer device, the above-mentioned 1
A classification circuit that divides a screen area into a plurality of large areas and classifies vector data belonging to the divided large areas, and a classification circuit that classifies vector data for each large area by the classification circuit to correspond to the large area. a vector classification memory that stores the vector data in a storage area, and a partial vector memory that reads and stores vector data for each major area from the vector classification memory, and stores the vector data read from the partial vector memory in the small partial area. A graphics printer device is provided.

The scan conversion method for vector information of one partial area used in the present invention is disclosed in Japanese Patent Application Laid-open No. 88435/1988 filed by the present applicant.

〔Example〕

Embodiments of the present invention will be described with reference to the accompanying drawings.

In Figure 1a, screen area 1 to be recorded
is divided into a large number of major regions 11-14. Among the vector data a to g, the vectors belonging to one of the major areas 12 are c, d, e, f, g.
The data regarding the vectors c, d, e, f, and g are stored in the storage area of the corresponding vector classification memory. In this case, among the vector data, data regarding vectors that also belong to other major areas, such as c, d, and g, are also stored in all the corresponding storage areas. In this way, after all the graphic data is classified and stored in the corresponding storage area, as shown in FIG. 1b,
One storage area, for example, 12, is taken out to a partial vector memory, and this major area is divided into small partial areas according to the division section upper and lower limit counters (divisions 121 to 125). Sequentially generating distribution pulses from the divided vector information, storing the distribution pulse signal in one of a plurality of storage devices which are cyclically switched in accordance with the division, and reading and scanning the stored information. This is repeated to create a scanning pattern signal for the entire screen.

FIG. 2 shows a schematic diagram of a graphic printer using a scan conversion method as an embodiment of the present invention.

Graphic data from a computer etc. 21 is sent to a classification circuit 22
The graphic data is classified as a group of graphic data belonging to each major area (11 to 14 in FIG. 1), and stored in the storage area of the vector classification memory 23 corresponding to the major area. The vector classification memory 23 is a large-capacity memory such as a magnetic disk memory or a magnetic drum memory, which is low in speed but has a low cost per bit, and has a capacity sufficient to store all of the graphic data to be handled. From the stored graphic data, one storage area (for example, 1 in Figure 1a)
2) is taken out to the partial vector memory 24, this major area 12 is divided into small partial areas (121 to 125) according to the specifications of the dividing section upper and lower limit counter 26, and distribution pulses are sequentially generated from the divided vector information. , a plurality of storage devices 28, 2 which can cyclically switch the distribution pulse signal in accordance with the division.
9, the stored information is read out to form a scanning pattern signal, and this is repeated to form a scanning pattern signal for the entire screen.

〔Effect of the invention〕

According to the present invention, it is possible to obtain a graphic printer device using a scan conversion method that can be constructed at low cost without reducing the recording speed even if the screen is large. That is, according to the present invention, the number of reproduction operations for wasteful portions when the entire screen is scan-converted at once is reduced to 1/N, where the number of partial area divisions is N. By appropriately selecting the size of the second vector memory, the write/read time of the first vector memory can be made shorter than when scanning and converting the entire screen at once, so it is possible to record the entire screen as a whole. The time can be significantly reduced. Note that since the vector memory only needs to have a small capacity, the device can be configured at low cost.

[Brief explanation of the drawing]

Figures 1a, b, and c show classification and division of screens containing vector graphics to which the present invention is applied, and Figure 2 provides an overview of a scan-conversion graphics printer as an embodiment of the present invention. show. 1: Screen area, 11, 12, 13, 14: Partial area, 121, 122, 123, 124, 12
5: Partial region division, 21: Computer, etc., 22: Classification circuit, 23: Vector classification memory, 24: Partial vector memory, 25: Scan conversion unit, 26: Division unit upper and lower limit counter, 27, 30: Switch, 2
8, 29: pattern memory, 31: printer section.

Claims (1)

[Claims] 1. One screen of vector data sent from a computer is divided into small partial areas, and a video signal based on the divided vector information is scan-converted via a plurality of pattern memories to generate one screen of graphics. A graphic printer device for printing, comprising: a classification circuit that divides the area of one screen into a plurality of major areas and classifies vector data belonging to the divided major areas; A vector classification memory that stores classified vector data in a storage area corresponding to the majority area, and a partial vector memory that reads and stores vector data for each major area from the vector classification memory, the partial vector memory A graphics printer device in which vector data read from a graphics printer is divided into small subareas.