
 SURFC, Introduction
 
 There are  three types  of surfaces which the user can define in
 QD3D.  They are : planes, cylinders and revolved arcs.
 
 Planes are  flat areas with straight lines or circles (i.e. arcs
 or one full circle) as edges.
 
 Cylinders are  "right circular  cylinders"  or  "right  circular
 cones" and  thus the  term "cylinders"  is used  in QD3D to mean
 both cylinders and cones (unless explicitly differentiated).
 
 Both can  be represented by the path swept by a straight line as
 it rotates about a rotation axis.
 
 A revolved arc is the path swept by an arc as it rotates about a
 rotation axis.   For example a semi-circle rotated by 360o about
 a line which passes through the ends of the arc, will generate a
 sphere.   A circle  rotated by  360o about some line external to
 the sphere will generate a torus.
 
 When the  SURFC command  is selected the user can manipulate the
 current surface  type :  for example  adding, deleting, changing
 etc.   The current  surface type is displayed in a tertiary menu
 which can  be altered  by the  SURFC TYPE command.  The tertiary
 menu will look like:-
 
 
                   Plane
                   
                  Cylinder
                  
                  Rev. Arc
                  
 
 
 Note:   When the  tertiary menu is altered the secondary menu is
 automatically altered to suit the new default surface type.

---------------------------------------------------------------------
---------------------------------------------------------------------

 SURFC (PLANE), Introduction
 
 Planes are  areas defined  by the user which may be free-standing
 or incorporate existing features of the drawing.
 
 Planes are  a very essential building block in QD3D. Whenever the
 user does  a hidden  edge or hidden (shaded) surface calculation,
 QD3D uses the relative position of the planes to draw the desired
 result.
 
 Once created,  planes can  be moved as complete elements, and can
 be modified  by suitable  manipulation of  any of  the individual
 defining points.
 
 When the command DRAW PLANE is executed, a small diamond is drawn
 at the  average corner  point of each individual plane. There are
 two ways to locate planes:
 
   1.   Locate one of the plane defining points with the alternate
        button.
   2.   Locate the  plane  centroid  diamond  with  the  selection
        button.
 
 In option  1, the  user may  inadvertently locate  a  point  that
 belongs to more than one plane.
 
 Planes cannot  be hatched  or filled  in QikDraw  3D because  the
 screen would become too cluttered.
 
 
 "PLANE ADD"
 
 Planes can  be added  by locating points on the screen (which may
 or may  not currently  exist). By  default, the plane will always
 close itself  from the last point added to the first point added.
 Note that  the points  used to  define a plane are drawn as small
 squares rather than small crosses for the sake of clarity.
 
 Procedure
 .   Locate  the   points  to   define  the   plane  pressing  the
     termination button to finish.
 
 
 "PLANE DEL"
 
 Planes can  be deleted  just like  any  other  entity.  The  user
 locates the plane by snapping to a defining point or locating its
 centroid diamond  with the  selection button  and that  plane  is
 deleted.
 

 "PLANE CHANG"
 
 When this  command is  selected a tertiary menu will appear which
 allows the  current values  of colour  and layer  to be  changed.
 This tertiary menu also allows the colour and/or layer of a group
 of planes  to be changed.  The method of locating the group is at
 the top of the tertiary menu (see POINT CHANG).
 
 
 "PLANE OUTLN"
 
 This command  allows the  user to  create  planes  using  current
 entities to  define the  plane. Unlike PLANE TRACE below, a plane
 can be  created with holes in the middle and with circles/arcs as
 definition entities.  This OUTLN  command is used for planes that
 are to be defined using  lines and circles.
 
 Any group of entities being traced must form a closed loop.
 
 If, when  the first loop has been traced, a holeo be defined
 within the  plane, answer  yes to  the "more  points?" prompt and
 trace around the inner shape as before.
 
 Procedure
 .   Locate a line or circle/arc. QikDraw adds plane points at the
     start and  end of  this entity.  Continue this  selection  of
     entities until  the loop closed and the first point added
     is the same as the last point of the last entity located.
 .   Specify "Add another outline (Y/N)?".
 .   If Y  then repeat,  tracing the  inner plane  in the opposite
     direction to the outer.
 
 
 "PLANE TRAC"
 
 This command  provides an  alternative means of generating planes
 which uses  existing connected  entities on  the sub-part for the
 plane definition.
 
 The user  initiates the  TRACE by  selecting a starting point for
 the plane.  Provided the pointconnected to lines, QD3D begins
 tracing along  a connected   user can definesub-parFve means of r
 
so ways ee eub-
 
 s  comlectiooc enegit selected tusphis canirst po the  means of  defsefine beowativmidd locacanather t,e.
 
 in def.er  initiatesat,  chooting .
 individua  defsefmoreed wfo  uscatings raa startin.
 indir plane locacaather th in a terre
  selecat, .
 
 mAny group  comnorefur smallong  a ted    sipulat(eg.rnatihis indivt by eted.
ee eub-
 
,ght  c 3D becaustlii the ane  isa  to   dg  thviouslyd.
ee eub-
 
 tracced, arethehe usto),CE by  selecry menbuttoe firsane.  Ptiates finike ustod   nt m e fi smalnts?" prompt ee typeoreedatesn.
dertiarur andurface tinition.
 
 Theen rso,CE bnt seledefi
 .   Locted tracin
,gpoint for  selection button  af  theline s ra end prompe user  itedC"
 
  selecprovides workd, aact). Bas the la plans
 ates tionoe sake ans2D, ac arcane  ising  cusn.
dcted cs as
 def/durvh usee hatchd
 withinPLAsRACE belmmand e lve
 plane srocedure
 .   Locate a Sbuttong point for
 theined
gposite
und tpecify "Abuttong ltetutton toprompe usfy "Onion button tortiary mnd t,d   nt m iflnts?" the
  defined rection withinPL 
 No--------------------------------------------------------------
---------------------------------------------------------------------

 SURFC (P(PLANE), ICYLINDERuction
 
 Planes arAs and conat(/arc.
)created envisr  lete acalculatia torus.dings raxis. ting 
 it ro lineon axis.
 
For exampTf the arc, will it s raweep lineoimagpo(see
 Plathen rtive padius indir p screo lr one fuiated),CE bntpart foculati finrc.
ath be r defic.
taposite
he l thenglrocedure  1wiareasre lapicthe drs and cones areaed by the path  line as
s thcircl connectiteinatlengby eides th  horiz.
tal e
 PlathepTf s defiictorial of the drcreated c.
spoiit the planeepart foculati nspherhoriz.
tal ides  locteren bgd caneaedsph
 PvelyxampTf tnumbroup
s raagd canereated cThe meser which maocedureF (shaded) 
 it rrhis r for vidua and conatyed i pointi nsptiongs r planhoriz.
tal eaagd can; viduaaagd caaced muar plan drawn onneane.  Plengby endir pla and con.mpTf tnumbroup
nhoriz.
tal aagd canatesr plured tleftaverage urface tyet. tinsoane  ir andand conaar w thech
 asmobe rtheends last er  e in orcrcle Butndary mgd caa Planesreated yet.mpTf turface tyet. tindephe arcnur andurface f colup
s rotated t berorcrcle (Vloctereny mgd caa Plasreatws thed sn.
ders rake ahaded) 

 it rrrhis r fo)athepNon- cylindersbefordrcreated reca torus.ding tyet. tinr planumbroup
nnhoriz.
tal aagd canrcnur aherhaded)  it rrhis r forning sses fnumbro.mple a semi-circdand con the  prak lahoriz.
tal aagd canr like:-
 
 
ng sther  tubrocedureTf twiareasre larhis r for reated wmadefinemimicnr plhaded)  it defiict Locng tyet. tinr plaeo l"ethel"athepTf ny mgd caa Plascat, .
o clutd, thelathennur an semi-cie  prak lahoriz.
tal aagd canr.  Thtroshaded) 
 it rrhis r fogiti.e. arc  ividuahis posite
wiars rare larhis r for o cluttather t,eirst poi locteren ines or circl the otinr plalengby ndir pldand conaar w joimand DRAnt oarc, wils defather tocedure  plane. Th and cones reated w
 .   Scng tyo a defi selectioleft.
ofinish.
he planetiteinahe ed c.
n
ln the scrrcng  the
   rent su.
n
lnofinishonhe plane deina defiof aircl "PLANE TRAANE), ICYLIN)
 Planes ca  command is  selecteda tertiary menu will appear which
 allows the  currak laiated).
locatees bei r forrcdand con1.   LocacacacacacacacacacacaLit r
   Locacacacacacacacacacaca
                  
       acaca
o              
       cacaLit rBodycedureTf tnt addf locatir thie drc.  Ptiate planes:
aed
gpot or locat thendrnatihis o   dg p
 o axis.   For e,e plg of n axis.
 
nglr th(+ve
 pla
ncteD3D.wise),eirste planes:
c.  Pd
gpot or eirstersane the scr
 noimagpo(see it rined
y  360o o linenate
r excedureTf t menu f locatir thie dr.  Pd
gpot or irsters ndir plaxis.
  ther e,e f t oint for
 thendir plbasal irc
 ca
 theinee  plane. s thengby ndiir pldand con, eirst that
 be the  plane. Uers ndir p.
oasal ircxcedureTf tmanrddf locatir thie dr.  Pd
gpot or irsters ndir plaxis.
  ther e,e f t oint for
 thendir plbasal irc
 ca
 theinee  plane. s thengby ndind DRAneeirst poipadius rtiary moseirc
 rst ta
 theintion entane. Uers ndir p
oasal ircxcedureTf tak lby  locatir thie dr.  Ptiate plsdd anot poipadius rtiaryt suand conairst pone planes:
ae it rined
g ofateody (bulk)-----LANE TRAANE), ICYLIN)
 Planes caline or cuand conainee 

.ANE TRAANE), ICYLIN)
UNPCKis command  provides unpackfinrcuand cona nspt eiity.   defieirstecircl thecRAnd forninhtroswiareasre lan.
 
 Th;ght  idiir plwiaresre ls raagd cas.
 
tion  t, thel uter.
 haded)  it raagd cas.
 
at, .
r pldand conaear whed wunpackertianinh circles.
sing  .hennubbe nesreelative ht igpo(Th and conrrrhmapoe,eiaru   ihe outernr planewes to  defi "PLANE TRAANE), ICYLIN)

 When this  command is  selected a tertiary  menu will appehich
 ed llows the  current values  of colour  and lay, a grouelecaagd cas.
 
aoified  The methomand   menu will appehis the colour and/or layer ofs th grouele of aagd cas.
 
p
 of plar  anand conesnged.  The metureTf t locatiing the groupp is at
 the toof the tertiary menu (seure POINT CHANG).
 
 
C (P(P------------------------------------------------------------
---------------------------------------------------------------------

 SURFC (P(PLANE), IREVOLVED ARCuction
 
 Planes ar
  olviarydefi(/arnts?"osedred t:onoupuladurvhd foculats)createdes tovisr  lete  acalculatica torus.ding taxis. tingn   dero lineons raxis.   For eocedure  1swiareaasre laapicthe drsr  olviar  defieiareaed by the paings rhoriz.
tal e
rstei locterene
 PlatheppTf nyhoriz.
tal e
 Pl o ways 
 iphe ilinderternr plaxis.
 
For e,e f g tyeowtcaby ndind s raweep.mpTf t locteren definarecophe sutiary t igpo(Thraw apTf s defiictorial of the drcreated c.
spoiit the planeepart foculati nspheraanumbroup
naagd canr   exireated cThe meser which maocedureF (shaded) 
 it rrhis rr for viduar  olviar  dected  i point nspheriongr planhoriz.
tal 
rst locteren bgd can; viduaaagd caaced muas rases father .mpTf tnumbroup
nhoriz.
tal 
rst locteren bgd caneted.
plured tlefta toof thturface tyet. tinnsoane  ipart foculatiar w thech
 asmobe rtlast r  en in orcrcle Butndary mgd caa Placreatedes yet.mpTf turface tyet. tindephe arcnur andurface f colup
i.e. a.
r berorcrcle Mr  e ited).
lsbefordrreated ca torus.ding yet. ti.
r plnumbrouup
nhoriz.
tal 
rs of  locteren bgd canecnur anhaded)s thcirrrhis rr for plsses fnumbros.mple a semi-circn ordarddspty.eatesr a torus.ding axis. ting semi-otated thrends 360oro linea  it defiae
   rerends tf the arc, willsemi-otated.e Butndary pty.erreaified  The me rning  bipyre iding e  me tinr plhaded)  it r locteres raagd caneninfr layernr plhoriz.
tal aagd canrninfr locedureTf twiar-sre laarhis r forreated cmadeffinemimicnr plhaded)  it defiict Locng tyet. tinr plaeo lmoreed "ethel" t:otf ny mgd caa Pla.
o clutd, thelacedure  plane. Thr  olviar  defireated c
 .   Scing yo a defii selectis theftaofinishlmor.
 indir pinafr lac.
n
ln the scrrcng  the
  .
r pld caralnofinishonhe plane deina def.ANE TRAANE), IREV. ARCu
 Planes ca  command is  selecteda tertiary menu will appear which
 allows the  currak laiated).
locatees bei r forrcdand con1.   LocacacacacacacacacAdec
  . LocacacacacacacacacSpty.eatecacacacacacacacacTorus LocacacacacacacacacAdecBodycedureTf tnt addf locatir thie drc.  Ptiate planes:
aed
gpot or locat thendrnatihis o   dg p
 o axis.   For e,e plg of n axis.
 
nglr th(+ve
 pla
nct-eD3D.wise),eirst planes:
an connectedircxcedureTf t menu ff locatir thie drcald carconnec plane y pty.erendrnane the einee  plan ta
lplane dey pty.excedureTf tmanrddf locatir thie drc.  Ptiate planes:
aed
gpot or locat thendrnatihis o   dg p
 oaxis.   For e,e plg of n axis.
 
nglr,.
r  poinctnotng point forr
 thendinr pla fogi plg of n aadius rt.
r pldtated snged. 
y  360o orste plg of  tf ththil360raln rtfyet thenglr
 pla
 f t oint endir pla tated.e  (and   rtfyet henglr
eted.
evpoince fin tyet. tinr plahaded)  it r  locteren bgd caneamoreas rases fnumbrou: e.g.rtia 45oe fin lteigt or ifnutcrrcwasty.)xcedureTf tak lby f locatir thie drc.  Ptiateamoresdd anotnr pla(liny.)s raadius rtiof the rusanirst ponte planes:
caldtated (i.d.e decofs tdtated)rined
g ofateody (bulk)---E TRAANE), IREV. ARCu
 Plane caline or cr  olviar decinee 

.ANE LANE TRAANE), IREV. ARCu
UNPCKis command  providesunpackfinrr  olviar decianin: eiity.  defincRAnd fo.
r  paneawiaresre lan.
 
 Th,ht  idir plwiaresre ly mgd caa Pla.
teda t h thel ternr plhaded)  it raagd cas.
 
at, nr pla  olvia thedecar whed
unpackertcianin circles.
sing  .hennubbe sreelative tht igpo(Thr  olviar decrhmapoe,eiar   ihe outerr plnew to  defi "PLANE TRAANE), IREV. ARCu

 When this  command is  selected a tertiary  menu will appehich
 ed llows the  current values  of colour  and lay, a grouelecaagd cas.
 
aoified  The methomand   menu will appehis the colour and/or layer ofs th grouele of  aagd cas.
 
p

 of plar
p
r  olviar  defimoreeds tdThe methoman t locating the group is at
 the toof the tertiary.
renu will appeT CHANG).
 
 
