Design: 04.01.01/P02

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PROGRAM 2: Appearance of polylines

CHARACTERISTICS: ynny

OPERATOR SCRIPT:

DEGENERATE POLYLINES: Some of the 6 labelled squares contain
a single point polyline, others contain a visible primitive
(including a single dot polylmarker).  Identify all the squares
in which no primitive is visible.

TWO-POINT POLYLINES: All the squares should contain a single line
segment.  All but one should have their endpoints accurately
circled by a polymarker.  Identify the line segment which is not
accurately marked.

MULTI-POINT POLYLINES: All the squares should contain a pentagon
with one side missing.  Identify the pentagon whose missing side
is different from that of the others.

GEOMETRY OF 3D POLYLINES: All the squares should contain a
polyline with multiple line segments.  All but one should have
their vertices accurately circled by a polymarker.  Identify the
polyline which is not accurately marked.

GEOMETRY OF 2D POLYLINES: Same as GEOMETRY OF 3D POLYLINES,
above.

DESIGN:

set polymarker scale factor to reasonable size = 0.02 in WC

Divide screen up into 6 square labelled areas for all tests

sider = list of 6 sides from which cube may be viewed =
  front,back,left,right,top,bottom

TEST: #SR 1 4 7
      "A <polyline> or <polyline 3> primitive with fewer than two
       points should have no visual effect."

ran6 = random order for 1-6
numemp = number of empty squares = random from 2 to 4
for ix = 1 to 6
   this = ran6(ix)
   if (this > numemp+1) then
      draw a single dot polymarker in area #ix
   elseif (this = numemp+1) then
      draw a single cross polymarker in area #ix
   elseif (this = numemp) then
      draw a single point 2D polyline in area #ix
   else
      draw a single point 3D polyline in area #ix
   endif
next ix
OPQA/DEGENERATE POLYLINES: List all the empty squares (caution:
  some squares may contain a dot-polymarker).
pass/fail depending on:
   (operator identifies the squares with single point polylines)

TEST: #SR 1 4 7
      "A <polyline> or <polyline 3> primitive with two points
       should be rendered as a single straight line segment
       connecting those points."

ngsq = no-good square = random integer from 1 to 6

for ix = 1 to 6
   rotate to view from sider(ix)
   if (ix <= 2) then
      draw two-point 2D polyline in square #ix (OK viewed from
         front or back only)
   else
      draw two-point 3D polyline in square #ix
   endif

   if (ix = ngsq) then
      use 2D circle polymarker to mark expected vertices inaccurately
   else
      use 2D circle polymarker to mark expected vertices correctly
   endif
next ix
OPQA/TWO-POINT POLYLINES: Which square contains something other
  than a single line segment with circled endpoints?
pass/fail depending on: (operator identifies square #ngsq)


TEST: #SR 1 4 7
      "A <polyline> or <polyline 3> primitive with a list of more
       than two points should be rendered by connecting each pair
       of adjacent points by a single straight line segment."

opensd = side of pentagon to leave open = random from 1 to 5

ran6 = random order for 1-6
for ix = 1 to 6
   this = ran6(ix)
   if (this <= 2) then
      draw 2D pentagon with open side = opensd, using one
        polyline for each segment
   elseif (this <= 5) then
      draw 3D pentagon with open side = opensd, using one
        polyline for whole figure
   else
      draw 2D pentagon with open side not= opensd
   endif
next ix

OPQA/MULTI-POINT POLYLINES: Which pentagon is open on a different side?
pass/fail depending on:
   (operator identifies square with open side not= opensd)


TEST: #SR 1 4 7
      "The appearance of a <polyline 3> primitive should reflect
       its 3D geometry after being transformed."

ngsq = no-good square = random integer from 1 to 6
generate 3D list of points, visually distinct from any side for
  3D polyline

for ix = 1 to 6
   rotate to view from sider(ix)
   display the 3D polyline in square #ix
   calculate expected position of vertices
   if (ix = ngsq) then
      distort expected vertices
   endif
   use 2D circle polymarker to mark expected vertices
next ix

OPQA/GEOMETRY OF 3D POLYLINES: Which polyline does NOT have
   all its vertices circled?
pass/fail depending on:
   (operator identifies square #ngsq)

TEST: #SR 1 4 7
      "The appearance of a <polyline> primitive should reflect
       its 2D geometry after being transformed."

ngsq = no-good square = random integer from 1 to 6
generate non-linear 2D list of points distinct from any side for
  2D polyline

for ix = 1 to 6
   rotate 45 degrees around x and y axis into unit cube to show
      z-values
   rotate to view from sider(ix)
   display the 2D polyline in square #ix
   calculate expected position of vertices
   if (ix = ngsq) then
      distort expected vertices
   endif
   use 2D circle polymarker to mark expected vertices
next ix

OPQA/GEOMETRY OF 2D POLYLINES: Which polyline does NOT have
   all its vertices circled?
pass/fail depending on:
   (operator identifies square #ngsq)

END PROGRAM 2