Line draw method for generating, storing and displaying lines in a display system

A line-draw method for drawing a line in a computer system comprising,

• drawing a plurality of line segments to form the line where each line segment has a segment length SL and includes a number U of pixels and a number A of pixels whereby SL equals U+A wherein said plurality of segments includes a beginning segment, one or more middle segments and an end segment and wherein each line segment is drawn by the steps of,
• drawing U pixels without condition evaluation,
• determining the number A of pixels to be drawn with condition evaluation,
• drawing A pixels.

A line-draw method for drawing a line in a computer system relative to an axes system with a major axis and an orthogonal minor axis, where the line has a projection da onto the major axis and a projection db onto the minor axis, where for the line, the average segment length ASL is equal to da/db, and where for one or more segments, the computer system executes an outer loop having executable instructions to draw the segment with a segment length, SL, by performing the steps of,

• determining the number A of pixels to be drawn with A less than or equal to a maximum number C by performing a maximum of A+1 tests, but not more than C tests, of a condition,
• drawing A pixels,
• drawing U pixels where,
• U.ltoreq.SL.ltoreq.(U+C)
• U.ltoreq.ASL.ltoreq.(U+C)

A line-draw method for drawing a line in a computer system relative to an axes system with a major axis and an orthogonal minor axis, where the line has a projection da onto the major axis and a projection db onto the minor axis, where for the line, the average segment length ASL is equal to da/db, and where the line includes a plurality of segments including a beginning segment, one or more middle segments and an end segment and for each middle segment, the computer system executes an outer loop having executable instructions to draw each middle segment with a segment length, SL, by performing the steps of,

• determining the number A of pixels to be drawn with A less than or equal to a maximum number C by performing a maximum of A+1 tests, but not more than C tests, of a condition,
• drawing A pixels,
• executing an unconditional loop having executable instructions "n" times where "n"=ULS and where ULS is the unconditional loop size representing the number of pixels drawn for each of the "n" executions of the unconditional loop,
• drawing U unconditional pixels, where,
• U.ltoreq.SL.ltoreq.(U+C)
• U.ltoreq.ASL.ltoreq.(U+C)
• drawing R remainder pixels, where,
• R=U ULS.

A line-draw method for drawing a line in a computer system relative to an axes system with a major axis and an orthogonal minor axis, where the line has a projection da onto the major axis and a projection db onto the minor axis, where for the line, the average segment length ASL is equal to da/db, and where the line includes a plurality of segments including a beginning segment, one or more middle segments and an end segment and for each middle segment, the computer system,

• executes an outer loop having executable instructions to draw a middle segment with a segment length, SL, by performing the steps of,
• drawing a number U of unconditional pixels where,
• U.ltoreq.SL,
• executing an inner loop of executable instructions A times to determine an actual number A of conditional pixels to be drawn where A is less than or equal to a maximum number C including,
• performing a maximum of A+1 tests, but not more than C tests, of a conditional-pixel condition to determine that A conditional pixels are to be drawn,
• drawing one conditional pixel for each iteration of the inner loop.

A line-draw method for drawing a line in a computer system relative to an axes system with a major axis and an orthogonal minor axis, where the line has a projection da onto the major axis and a projection db onto the minor axis, where for the line, the average segment length ASL is equal to da/db, and where the line includes a plurality of segments including a beginning segment, one or more middle segments and an end segment and for each middle segment, the computer system,

• executes an outer loop having executable instructions to draw a middle segment with a segment length, SL, by performing the steps of,
• drawing a number U of unconditional pixels where,
• U.ltoreq.SL,
• U=2,
• 2.ltoreq.SL,
• executing an inner loop of executable instructions A times to determine an actual number A of conditional pixels to be drawn where A is less than or equal to a maximum number C including,
• performing a maximum of A+1 tests, but not more than C tests, of a conditional-pixel condition to determine that A conditional pixels are to be drawn,
• drawing one conditional pixel for each iteration of the inner loop.

A line-draw method for drawing a line in a computer system comprising,

• partitioning the line into a plurality of multi-pixel segments where each segment is formed of a number U of unconditional pixels and up to a maximum number C of conditional pixels, and
• for each segment,
• drawing U unconditional pixels,
• determining an actual number A of conditional pixels to be drawn where the actual number A is less than or equal to the maximum number C,
• drawing A conditional pixels.

A line-draw method for drawing lines in a computer system where the lines are drawn relative to an axes system with a major axis and an orthogonal minor axis, where each one of the lines has a projection da onto the major axis and a projection db onto the minor axis, where for each line, an average segment length ASL is equal to da/db for that line, the steps for any particular line of arbitrary direction or length comprising,

• providing a plurality of segment loops where each segment loop includes executable instructions, each segment loop for drawing a range of average segment lengths, said plurality of segment loops including a complete set of segment loops having a complete set of average segment lengths such that any line of arbitrary direction and length may be drawn,
• selecting one of the segment loops as the selected loop for said particular line,
• partitioning the particular line into a plurality of multi-pixel segments where each segment is formed of a number U of unconditional pixels and an actual number A of conditional pixels not greater than a maximum number C of conditional pixels, and
• for each segment of said particular line executing said selected segment loop as follows,
• drawing U unconditional pixels,
• determining the actual number A of conditional pixels to be drawn,
• drawing A conditional pixels.

A line-draw apparatus for drawing a line in a computer system comprising,

• means for drawing a plurality of line segments to form the line where each line segment has a segment length SL and includes a number U of pixels and a number A of pixels whereby SL equals U+A and wherein for each line segment said means for drawing includes,
• means for drawing U pixels without condition evaluation,
• means for determining the number A of pixels to be drawn with condition evaluation, wherein said means for determining the number A of pixels is operational A times,
• means for drawing A pixels.

A line-draw apparatus for drawing a line in a computer system comprising,

• means for drawing a plurality of line segments to form the line where each line segment has a segment length SL and includes a number U of pixels and a number A of pixels whereby SL equals U+A, wherein said plurality of segments includes a beginning segment, one or more middle segments and an end segment and wherein for each line segment said means for drawing includes,
• means for drawing U pixels without condition evaluation,
• means for determining the number A of pixels to be drawn with condition evaluation,
• means for drawing A pixels.

A line-draw apparatus for drawing a line in a computer system where the line has a direction and a length, where the line is formed by a plurality of line segments and where, in the computer system, one or more segment loops having executable instructions are provided and, for each segment, one of the segment loops is executed to draw the segment, and wherein in response to one or more of said segment loops includes, said apparatus includes,

• means for drawing a number U of pixels unconditionally,
• means for determining an actual number A of pixels to be drawn as a function of a condition, and wherein said condition in the means for determining an actual number A of pixels to be drawn for each segment operates as a function of said direction and length,
• means for testing said condition once for each of said number A of pixels to be drawn,
• means for drawing A pixels.

A line-draw apparatus for drawing a line in a computer system relative to an axes system with a major axis and an orthogonal minor axis, where the line has a projection da onto the major axis and a projection db onto the minor axis, where for the line, the average segment length ASL is equal to da/db, and where for one or more segments, the computer system executes an outer loop having executable instructions to draw the segment with a segment length, SL, said apparatus comprising,

• means for determining the number A of pixels to be drawn with A less than or equal to a maximum number C including means for performing a maximum of A+1 tests, but not more than C tests, of a condition,
• means for drawing A pixels,
• means for drawing U pixels where,
• U.ltoreq.SL.ltoreq.(U+C)
• U.ltoreq.ASL.ltoreq.(U+C)

A line-draw apparatus for drawing a line in a computer system relative to an axes system with a major axis and an orthogonal minor axis, where the fine has a projection da onto the major axis and a projection db onto the minor axis, where for the fine, the average segment length ASL is equal to da/db, and where the line includes a plurality of segments including a beginning segment, one or more middle segments and an end segment and for each middle segment, the computer system executes an outer loop having executable instructions to draw each middle segment with a segment length, SL, comprising,

• means for determining the number A of pixels to be drawn with A less than or equal to a maximum number C by performing a maximum of A+1 tests, but not more than C tests, of a condition,
• means for drawing A pixels,
• means for executing an unconditional loop having executable instructions "n" times where "n"=ULS and where ULS is the unconditional loop size representing the number of pixels drawn for each of the "n" executions of the unconditional loop,
• means for drawing U unconditional pixels, where,
• U.ltoreq.SL.ltoreq.(U+C)
• U.ltoreq.ASL.ltoreq.(U+C)
• means for drawing R remainder pixels, where,
• R=U ULS.