Method of displaying thick line and information unit and display system used therefor

A method of displaying a thick line for displaying the thick line by parallel setting a reference line component and at least one additional line component which is obtained by parallel moving said reference line component, comprising:

• a step for carrying out a first clipping processing to the reference line component such that a first clip frame showing a display range is expanded by a predetermined width equal to or larger than a total width of the at least one additional line component to be set at least at one side of the reference line component to obtain a second clip frame and obtaining line components in the second clip frame;
• a step for obtaining the at least one additional line component in addition to the reference line component after the above processing;
• a step for obtaining a pixel which constitutes the reference line component that has been first clipping processed and the at least one additional line component obtained;
• a step for carrying out a second clipping processing to a picture element obtained to obtain a pixel within the first clip frame;
• and
• a step for displaying the pixel obtained within the first clip frame.

A display system comprising:

• means for displaying a thick line by parallel setting a reference line component and at least one additional line component which is obtained by parallel moving said reference line component;
• means for carrying out a first clipping processing to the reference line component such that a first clip frame showing a display range is expanded by a predetermined width equal to or larger than a total width of the at least one additional line component to be set at least at one side of the reference line component to obtain a second clip frame and obtaining line components in the second clip frame;
• means for obtaining a pixel which constitutes the reference line component that has been the first clipping processed and the at least one additional line component obtained;
• means for carrying out a second clipping processing to the pixel obtained to obtain a pixel within the first clip frame;
• and
• means for displaying the pixel obtained within the first clip frame.

A display system comprising:

• means for displaying a thick line by parallel setting a reference line component and at least one additional line component having start and end points obtained by parallel moving start and end points of said reference line;
• means for carrying out a first clipping processing to the reference line component such that a first clip frame showing a display range is expanded by a predetermined width equal to or larger than a total width of the at least one additional line component to be set at least at one side of the reference line component to obtain a second clip frame and obtaining start and end points of line components within the second clip frame;
• means for obtaining the start and end points of the at least one additional line component next to the reference line component obtained by the first clipping processing;
• means for generating a pixel of the reference line component and the at least one additional line component from the start and end points of the reference line component obtained by the first clipping processing and the at least one additional line component obtained;
• means for discriminating whether coordinates of the pixel generated are within the first clip frame or not;
• and
• means for displaying the pixel when the coordinates of the pixel discriminated are within the first clip frame.

An information processing unit which provides a multi-window environment and has means for displaying a thick line by parallel setting a reference line component and at least one additional line component having start and end points obtained by parallel moving start and end points of said reference line component, to realize a clipping processing of the thick line which is displayed in one window by dividing the one window into two or more clip frames and by clipping processing each of the clip frames, said information processing unit comprising for each clip frame:

• means for carrying out a first clipping processing to the reference line component of the thick line such that a first clip frame showing a display range is expanded by a predetermined width equal to or larger than a total width of the at least one additional line component to be set at least at one side of the reference line component and obtaining line components in the second clip frame;
• means for obtaining a pixel which constitutes the reference line component that has been the first clipping processed and the at least one additional line component obtained;
• means for carrying out a second clipping processing to the picture element obtained to obtain a pixel within the first clip frame;
• and
• means for displaying the pixel obtained within the first clip frame.