A computer graphics display system including random access raster memory for storing data to be displayed, a raster memory control unit for writing data into the raster memory, a video control unit for causing such information to be displayed on a CRT display screen, a micro control unit for controlling the function and timing of the raster memory control unit and the video control unit, and a computer adapted for facilitating data exchange between the micro control unit and a host computer. The displayed image can have extremely high complexity with essentially no problem of display flicker. Zoom and pan features allow the use of a very complex stored image in a flexible manner, and a split-screen technique enables an operator to work on a very complex picture at a detail level while still having an overview of the total picture, or any portion thereof, simultaneously presented before him. The split-screen feature also allows the simultaneous display of alphanumeric messages such as prompts, menus, or X-Y readouts added to the graphics display and a small area of the raster memory is usually reserved for this purpose. An XOR feature allows a selective erase that restores lines crossing or concurrent with erased lines. The XOR feature permits part of the drawing to be moved or "dragged" into place without erasing other parts of the drawing.
In a distributed data processing system having a plurality of terminals or workstations, and providing the ability for users at terminals to access complex graphic images from a mainframe host and manipulate them at their terminals for inclusion into their own works, a method is provided for manipulating elements of an image too complex or detailed to be displayed in their entirety on a terminal. Demarkation may be performed at one portion of the image, and may be completed in another portion of the image in which the first portion is off screen.
A zigzag scanning address generator includes a row address generator for generating a row address signal which stops, increases or decreases a present state in response to an enabling signal, and a column address generator for generating a column address signal which stops, increases or decreases a present state in response to the enabling signal. Therefore, the zigzag scanning address generator can generate zigzag scanning addresses according to a zigzag scanning method, simplifying the circuit configuration needed for generating the address signals corresponding to the zigzag scanning pattern.
In a display signal generating means in a display device for both the character display and the graphic display, address conversion means is provided for converting the addresses of one character in a plurality of lines of one character section of a memory field corresponding to a display panel into a predetermined address or addresses.
An inspection and adjustment of a liquid crystal module have required a number of processes, which has been inefficient.According to the present invention, OSD image data is stored in a ROM 42 of a liquid crystal module 10, and the liquid crystal module 10 can independently display a plurality of test patterns simply by receiving a remote-control signal from a remote-control signal transmitter 60. Therefore, simply by putting the liquid crystal module on an inspection line 70, at each inspection station 71, a display pattern necessary for each inspection and adjustment is automatically switched and shown. Therefore, the inspection and adjustment of the liquid crystal module can be conducted without a process of connecting an exclusive substrate 110 and an image data generator 120 which used to be required only during the inspection and adjustment of each liquid crystal module 10 and a process for a worker to operate a prescribed device every time the type of inspection changes.
Touch controlled zoom of a waveform display uses a touch screen for the display surface. Function buttons for moving or expanding the waveform display and for determining the axis of such movement or expansion operate in conjunction with a rotary encoder. Expansion, or zoom, is accomplished by contacting the screen overlying a point on the waveform about which zoom is desired. Such contact or activation of the expand function button results in movement of the rotary encoder providing a gain parameter to a zoom function. The zoom function operates on the waveform display in an exponential manner as a function of the gain parameter to expand or contract the waveform display about the zoom point according to the direction of rotation of the rotary encoder.