TweetFollow Us on Twitter

Graf3D
Volume Number:4
Issue Number:6
Column Tag:Forth Forum

Graf3D Library Access

By Jörg Langowski, MacTutor Editorial Board

Graf3D and Mach2 - accessing external libraries

The subject of this month has been initiated by one of our readers, Paul Thomas, who in a desperate mood sent me both a paper letter and GEnie mail, because he needed to know whether it would be possible at all to access the Graf3D routines from Mach2.

A little background for those who weren’t with the Mac (or with us, for that matter) from the beginning: Graf3D is a set of routines on top of QuickDraw, which enable to create a 3-d GrafPort with all necessary support to do 3-dimensional perspective drawing. The routines aren’t explained in Inside Macintosh, but in several other different documents, one of them being the MPW Pascal manual (Appendix J).

Graf3D was also part of the Lisa Workshop, and one of the first Macintosh demo programs, Boxes, used those routines. The Boxes program - many of you might have seen it - draws at random fifteen rectangular boxes on a plane and displays them in a 3-d perspective view. The program is written originally in Lisa Pascal, and also contained on the TML Pascal disk as an example. Listing 4 shows the original program.

Glancing through the code, you might notice that this example certainly wouldn’t please the User Interface Thought Police today. Using the whole screen as a GrafPort without regard to anything else on there is a definite no-no in the days of Multifinder, and if you run the example under Multifinder, you won’t find your windows back on the screen afterwards because they are all covered by little boxes. Nevertheless, it is a nice example for the use of Graf3D, and we’ll show you this month how to translate it into Mach2 (We’ll also correct the garbled screen problem under Multifinder).

First and most difficult question: How can we access routines from Forth that are clearly labeled (Not in ROM) in the documentation? This remark tells us, of course, that they are part of some object library, no source code available and inaccessible to the Forth user. Just like the printing manager was before it was implemented in the Mach2 and MacForth systems.

There may be other libraries to come, also not in ROM, and waiting for updates takes a long time. So I’ll give you two general strategies to get access to object library code from Forth, making you independent of those updates.

The first scheme I thought up was simply to write a short Pascal program that calls all the routines at least once - so that they will be loaded -, compile that program, create a linker map if possible, and pass the final application through Nosy. That will get you a more or less annotated assembly listing from which you can extract the source code of the not in ROM routines that you are interested in.

Well, that works for you and me on our respective desks, but we certainly cannot publish reverse-engineered Apple source code in MacTutor, at least if we want to stay in business. Also, it is a lot of work (i.e. translating to a different assembler dialect, writing the glue code, etc.), and all in all qualifies as a master example of a dirty hack.

There is an easier way to go, and much more general, too: write some sort of a linker for Pascal library code. We write an assembly main program (Listing 2), which is just a table of JMP instructions to the routines that we want to call, and let the MPW linker do its job (listing 3).

The assembly/link script will create a new resource, gr3D, which contains the jump instructions at the beginning, followed by the linked Graf3D code. All we have to do now is to provide a block of memory in our Forth code where this resource can be copied to.

In order to assign Forth words to the JMP instructions, we simply make a table of CREATEs, which will allocate 4 bytes to each name (the length of a JMP d(PC) instruction), and create a dictionary entry so that we know the routine’s address in the jump table. After the block of CREATEs, we allocate sufficient memory so that the gr3D resource can be loaded (see listing 1).

We write a word, Init3D, that gets the gr3D resource and copies it into the table, starting with the address of the first Graf3d word, gInitGrf3D. Now the Graf3D routines are all set up for use by Mach2. As simple as that.

Well, not quite. We still need to write glue code to move the parameters from the Forth stack (A6) to the Pascal stack (A7). That glue code is rather simple and is just the same as is used for calling toolbox ROM routines. Like the traps, the Graf3D code preserves all registers that are vital to Mach2 (A2-A7, D4-D7). Like in the case of traps, we have to make A7 point to the lowest stack (EXG D4,A7) in order to avoid overwriting of Mach2 space by the intermediate Quickdraw record that is put between the stack and the heap. The glue code for the different Graf3D routines is given at the beginning of listing 1.

The Boxes examples should be self-explanatory when you compare it with the Pascal code; in fact, it might help some of you Pascal programmers and casual Forth readers appreciate that there is really no big difference between Forth and Pascal code...

I should point out some more things. First, the ‘access words’ for fields in a record, .x, .y, .pt1, and so on, defined at the beginning of the Forth code. Second, the word restore.screen, which cleans up the display after the example has run; very important when running under Multifinder. It basically does a PaintBehind(FrontWindow, grayRgn), the same mechanism by which many screen savers restore a blacked-out screen. Third, we define a terminal task that runs the Boxes example; that way, we can simply check for ?terminal after each drawing loop to see whether we’re done. Again, we have to make sure (like always in Mach2 multitasking) that the correct GrafPort is set by calling myPort3D SetPort3D before each passage through the loop. This is because any PAUSE-containing word, such as ?terminal, may change the active GrafPort.

For using the example, you will first have to create the Graf3Dglue resource file with the gr3D resource in it, then move that resource into the MACH.RSRC file before starting your Mach2 system. In case you don’t have access to MPW, the source code disk contains the Graf3Dglue and MACH.RSRC files. The complete program, of course, is also on the disk.

That’s it for this month; next month I plan to discuss various projects of object-oriented extensions to Mach2 that have recently appeared on the networks. Some of you might also appreciate that NEON hasn’t died altogether, but that there is at least one person trying to extend it in a very interesting way.

Listing 1: The Boxes example in Mach2
\ Graf3d / Mach2 glue code
\ An example for calling MPW routines from Forth
\ J. Langowski April 1988
\ __________________________________________
Only Forth Also Mac Also Assembler

\ some general definitions first
16 CONSTANT portRect

GLOBAL
 CODE SCALE
    MOVE.L   (A6)+,D0
    BMI.S    @1
    MOVE.L   (A6),D1
    ASL.L    D0,D1
    MOVE.L   D1,(A6)
    RTS
@1  MOVE.L   (A6),D1
    NEG.L    D0
    ASR.L    D0,D1
    MOVE.L   D1,(A6)
    RTS
END-CODE

global
CODE white
 MOVE.L (A5),-(A6)
 SUBQ.L #8,(A6)
 RTS
END-CODE MACH

global
CODE black
 MOVE.L (A5),-(A6)
 SUBI.L #16,(A6)
 RTS
END-CODE MACH

global
CODE gray
 MOVE.L (A5),-(A6)
 SUBI.L #24,(A6)
 RTS
END-CODE MACH

: 4ASCII 
 0
4 0 DO
  8 SCALE 0 WORD 1+ C@ + 
LOOP
;

4ASCII gr3D CONSTANT “gr3D \ resource ID

\ Graf3D jump table

CREATE  gInitGrf3D
CREATE  gOpen3DPort
CREATE  gSetPort3D 
CREATE  gGetPort3D 
CREATE  gMoveTo2D
CREATE  gMoveTo3D
CREATE  gLineTo2D
CREATE  gLineTo3D
CREATE  gMove2D
CREATE  gMove3D
CREATE  gLine2D
CREATE  gLine3D
CREATE  gViewPort
CREATE  gLookAt
CREATE  gViewAngle
CREATE  gIdentity
CREATE  gScale
CREATE  gTranslate
CREATE  gPitch
CREATE  gYaw
CREATE  gRoll
CREATE  gSkew
CREATE  gTransform
CREATE  gClip3D
CREATE  gSetPt3D
CREATE  gSetPt2D

\ The glue code is 2636 bytes long, so we allocate
\ sufficient additional buffer space to put it into
2600 ALLOT

: Init3D \ gets Graf3D code from gr3D=1 resource 
  \ and copies it into buffer
 “gr3D 1 call GetResource
 dup @ swap call SizeRsrc
 [‘] gInitGrf3D swap cmove
;

CODE InitGrf3d ( globalPtr -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gInitGrf3d
 EXG  D4,A7
 RTS
END-CODE

CODE Open3DPort  ( port -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gOpen3DPort
 EXG  D4,A7
 RTS
END-CODE

CODE SetPort3d ( port -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gSetPort3d
 EXG  D4,A7
 RTS
END-CODE

CODE GetPort3d ( VAR port -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gGetPort3d
 EXG  D4,A7
 RTS
END-CODE

CODE MoveTo2d  ( x y -- )
 EXG  D4,A7
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #8,A6
 JSR  gMoveTo2d
 EXG  D4,A7
 RTS
END-CODE

CODE MoveTo3d  ( x y z -- )
 EXG  D4,A7
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #12,A6
 JSR  gMoveTo3d
 EXG  D4,A7
 RTS
END-CODE

CODE LineTo2d  ( x y -- )
 EXG  D4,A7
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #8,A6
 JSR  gLineTo2d
 EXG  D4,A7
 RTS
END-CODE

CODE LineTo3d  ( x y z -- )
 EXG  D4,A7
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #12,A6
 JSR  gLineTo3d
 EXG  D4,A7
 RTS
END-CODE

CODE Move2d ( dx dy -- )
 EXG  D4,A7
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #8,A6
 JSR  gMove2d
 EXG  D4,A7
 RTS
END-CODE

CODE Move3d ( dx dy dz -- )
 EXG  D4,A7
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #12,A6
 JSR  gMove3d
 EXG  D4,A7
 RTS
END-CODE

CODE Line2d ( x y -- )
 EXG  D4,A7
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #8,A6
 JSR  gLine2d
 EXG  D4,A7
 RTS
END-CODE

CODE Line3d ( x y z -- )
 EXG  D4,A7
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #12,A6
 JSR  gLine3d
 EXG  D4,A7
 RTS
END-CODE

CODE ViewPort  ( r -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gViewPort
 EXG  D4,A7
 RTS
END-CODE

CODE LookAt ( left top right bottom -- )
 EXG  D4,A7
 MOVE.L 12(A6),-(A7)
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #16,A6
 JSR  gLookAt
 EXG  D4,A7
 RTS
END-CODE

CODE ViewAngle ( angle -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gViewAngle
 EXG  D4,A7
 RTS
END-CODE

CODE Identity
 EXG  D4,A7
 JSR  gIdentity
 EXG  D4,A7
 RTS
END-CODE

CODE Scal ( xfactor yfactor zfactor -- )
 EXG  D4,A7
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #12,A6
 JSR  gScale
 EXG  D4,A7
 RTS
END-CODE

CODE Translate ( dx dy dz -- )
 EXG  D4,A7
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #12,A6
 JSR  gTranslate
 EXG  D4,A7
 RTS
END-CODE

CODE Pitch( xangle -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gPitch
 EXG  D4,A7
 RTS
END-CODE

CODE Yaw( yangle -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gYaw
 EXG  D4,A7
 RTS
END-CODE

CODE Rol( zangle -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gRoll
 EXG  D4,A7
 RTS
END-CODE

CODE Skew ( zangle -- )
 EXG  D4,A7
 MOVE.L (A6)+,-(A7)
 JSR  gSkew
 EXG  D4,A7
 RTS
END-CODE

CODE Transform ( src dst -- )
 EXG  D4,A7
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #8,A6
 JSR  gTransform
 EXG  D4,A7
 RTS
END-CODE

CODE Clip3D ( src1 src2 dst1 dst2 -- flag )
 EXG  D4,A7
 CLR.W  -(A7)
 MOVE.L 12(A6),-(A7)
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #16,A6
 JSR  gClip3D
 MOVE.W (A7)+,D0
 EXT.L  D0
 MOVE.L D0,-(A6)
 EXG  D4,A7
 RTS
END-CODE

CODE SetPt3d( pt3D x y z -- )
 EXG  D4,A7
 MOVE.L 12(A6),-(A7)
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #16,A6
 JSR  gSetPt3D
 EXG  D4,A7
 RTS
END-CODE

CODE SetPt2d( pt2D x y -- )
 EXG  D4,A7
 MOVE.L 8(A6),-(A7)
 MOVE.L 4(A6),-(A7)
 MOVE.L (A6),-(A7)
 ADDA.W #12,A6
 JSR  gSetPt2D
 EXG  D4,A7
 RTS
END-CODE

\ Translation of Boxes.pas example into Forth follows
\ _________________________________________

: .x ; mach
: .y 4 + ; mach
: .z 8 + ; mach

: .pt1 ; mach
: .pt2 12 + ; mach

15 CONSTANT BoxCount
Variable MyPort  104 vallot 
 \ grafPort is 108 bytes long
Variable MyPort3D  150 vallot 
 \ graf3DPort is 154 bytes long
Variable boxArray   24 BoxCount * vallot 
 \ BoxCount * 2* point3D @ 3 long words
Variable nboxes     \ # of boxes made
Variable MyBox   20 vallot \ 24 bytes for 2* point3d
Variable p1   8 vallot \ point3d
Variable p2   8 vallot \ point3d
Variable myRect    4 vallot \ Rect
Variable testRect   4 vallot \ Rect

: DrawBrick { pt1 pt2 | tempRgn -- }
 call NewRgn -> tempRgn

 call OpenRgn  
 pt1 .x @ pt1 .y @ pt1 .z @ MoveTo3D
 pt1 .x @ pt1 .y @ pt2 .z @ LineTo3D
 pt2 .x @ pt1 .y @ pt2 .z @ LineTo3D
 pt2 .x @ pt1 .y @ pt1 .z @ LineTo3D
 pt1 .x @ pt1 .y @ pt1 .z @ LineTo3D
 tempRgn call CloseRgn
 tempRgn white call FillRgn

 call OpenRgn
 pt1 .x @ pt1 .y @ pt2 .z @ MoveTo3D
 pt1 .x @ pt2 .y @ pt2 .z @ LineTo3D
 pt2 .x @ pt2 .y @ pt2 .z @ LineTo3D
 pt2 .x @ pt1 .y @ pt2 .z @ LineTo3D
 pt1 .x @ pt1 .y @ pt2 .z @ LineTo3D
 tempRgn call CloseRgn
 tempRgn gray call FillRgn

 call OpenRgn  
 pt2 .x @ pt1 .y @ pt1 .z @ MoveTo3D
 pt2 .x @ pt1 .y @ pt2 .z @ LineTo3D
 pt2 .x @ pt2 .y @ pt2 .z @ LineTo3D
 pt2 .x @ pt2 .y @ pt1 .z @ LineTo3D
 pt2 .x @ pt1 .y @ pt1 .z @ LineTo3D
 tempRgn call CloseRgn
 tempRgn black call FillRgn

 white call penpat
 pt2 .x @ pt2 .y @ pt2 .z @ MoveTo3D
 pt2 .x @ pt2 .y @ pt1 .z @ LineTo3D
 pt2 .x @ pt1 .y @ pt1 .z @ LineTo3D
 call pennormal

 tempRgn call DisposRgn
;

: hi -16 scale ;

: chkBox { | box -- }
 1 ( flag )
 nBoxes @ 0 DO
 boxArray i 24 * + -> box
 testRect  
 box .pt1 .x @ hi   
 box .pt1 .y @ hi 
 box .pt2 .x @ hi 
 box .pt2 .y @ hi  call SetRect
 testRect -1 -1 call InSetRect
 myRect testRect testRect call SectRect
 IF drop 0 leave THEN
 LOOP
;

: MakeBox { | p1x p1y p1z p2x p2y p2z box ii -- }
 call random 70 mod 15 - 1 call FixRatio -> p1x
 call random 70 mod 10 - 1 call FixRatio -> p1y
 0 -> p1z

 call random 30 mod abs 10 + 1 call FixRatio p1x + 
 -> p2x
 call random 45 mod abs 10 + 1 call FixRatio p1y + 
 -> p2y
 call random 30 mod abs 10 + 1 call FixRatio p1z + 
 -> p2z

 myRect p1x hi p1y hi p2x hi p2y hi call SetRect

 chkBox IF
 p1x myBox .pt1 .x !
 p1y myBox .pt1 .y !
 p1z myBox .pt1 .z !
 p2x myBox .pt2 .x !
 p2y myBox .pt2 .y !
 p2z myBox .pt2 .z !

 0 -> ii
 myBox boxArray nBoxes @ 24 * + 24 cmove

 BEGIN
 myBox .pt1 .y @  boxArray ii + .pt2 .y @ >
 myBox .pt2 .y @  boxArray ii + .pt1 .y @ > and
 myBox .pt1 .x @  boxArray ii + .pt2 .x @ <
 myBox .pt2 .x @  boxArray ii + .pt1 .x @ < and or
 WHILE
 24 +> ii
 REPEAT
 ii 24 / -> ii

 ii 1+ nBoxes @ DO
 boxArray i 1- 24 * +
 boxArray i 24 * + 
 24 cmove
 -1 +loop
 myBox boxArray ii 24 * + 24 cmove
 
 1 nBoxes +!
 THEN
;

: drawGrid
 11 -10 DO
 i 10 * 1 call FixRatio -100 1 call FixRatio 0
 MoveTo3D
 i 10 * 1 call FixRatio  100 1 call FixRatio 0
 LineTo3D
 LOOP

 11 -10 DO
 -100 1 call FixRatio i 10 * 1 call FixRatio 0
 MoveTo3D
  100 1 call FixRatio i 10 * 1 call FixRatio 0
 LineTo3D
 LOOP
;

: restore.screen
 call drawmenubar
 call frontwindow 
 grayrgn @ call paintbehind
 call showcursor
;

: main
 init3d
 call hidecursor
 myPort call OpenPort
 myPort3D Open3DPort
 myPort portRect + ViewPort
 -100 1 call FixRatio  75 1 call FixRatio
  100 1 call FixRatio -75 1 call FixRatio
 LookAt
 30 1 call FixRatio ViewAngle
 Identity
 20 1 call FixRatio Rol
 70 1 call FixRatio Pitch 

 BEGIN
 myPort3D SetPort3D
 0 nBoxes !
 BEGIN makeBox nBoxes @ boxCount = UNTIL

 white call penPat
 black call backPat
 myPort portRect + call EraseRect

 drawGrid

 0 nBoxes @ 1- DO
 boxArray i 24 * + 
 dup .pt1 swap .pt2 DrawBrick
 -1 +LOOP 
 
 ?terminal UNTIL
 restore.screen
 bye
;

NEW.WINDOW Boxes
“ Boxes” Boxes TITLE
0 0 20 20 Boxes BOUNDS
Plain Visible NoCloseBox NoGrowBox Boxes ITEMS

600 5000 terminal Box

: go.box activate main ;

: start
 Boxes add
 Boxes Box build
 Box go.Box
; 

.( To create a turkey application ) cr
.( type TURNKEY START BOXES )
Listing 2: MPW Assembly glue code for accessing the Graf3D Pascal library
 TITLE  ‘Graf3D glue code for Mach2’
 BLANKS OFF 
 PRINT  OFF
 INCLUDE  ‘Traps.a’
 INCLUDE  ‘ToolEqu.a’
 INCLUDE  ‘QuickEqu.a’
 INCLUDE  ‘SysEqu.a’
 INCLUDE  ‘Graf3DEqu.a’
 PRINT  ON

GrafGlueMAIN
 JMP   InitGrf3D
 JMP   Open3DPort
 JMP   SetPort3D
 JMP   GetPort3D
 JMP   MoveTo2D
 JMP   MoveTo3D
 JMP   LineTo2D
 JMP   LineTo3D
 JMP   Move2D
 JMP   Move3D
 JMP   Line2D
 JMP   Line3D
 JMP   ViewPort
 JMP   LookAt
 JMP   ViewAngle
 JMP   Identity
 JMP   Scale
 JMP   Translate
 JMP   Pitch
 JMP   Yaw
 JMP   Roll
 JMP   Skew
 JMP   Transform
 JMP   Clip3D
 JMP   SetPt3D
 JMP   SetPt2D
 END  
Listing 3: MPW assembly / link script for generating the gr3D resource 
(to be put into the MACH.RSRC file)
 Asm Graf3dglue.a -l
 Link Graf3dglue.a.o 
 {Libraries}Interface.o 
 -rt gr3D=1 -o Graf3dglue -l > Graf3dglue.map
Listing 4: The original Boxes example (from TML Pascal)
 PROGRAM Boxes;

{ Boxes demonstrates the use of the Three Dimensional
Quickdraw package Graf3D.

  Pascal source:  Boxes.Pas
  Resources:      *none*
  
  This program is from Apple’s Lisa Software Supplement,
modified for TML Systems Pascal compiler.
}

USES MacIntf, FixMath, Graf3D;

CONST boxCount = 15;
 keyOrMouse = 10;

TYPE  Box3D = 
     RECORD
 pt1: Point3D;
 pt2: Point3D;
     END;

VARmyPort:   GrafPort;
 myPort3D: Port3D;
 boxArray: ARRAY [0..boxCount] OF Box3D;
 nBoxes:   INTEGER;
 i:        INTEGER;
 dummy:    EventRecord;
      
PROCEDURE DrawBrick(pt1, pt2: Point3D);
{ draws a 3D brick with shaded faces.  
  only shades correctly in one direction.
}
VARtempRgn: RgnHandle;
BEGIN
   tempRgn := NewRgn;
   OpenRgn;
   MoveTo3D(pt1.X, pt1.Y, pt1.Z); { front face, y=y1 }
   LineTo3D(pt1.X, pt1.Y, pt2.Z);
   LineTo3D(pt2.X, pt1.Y, pt2.Z);
   LineTo3D(pt2.X, pt1.Y, pt1.Z);
   LineTo3D(pt1.X, pt1.Y, pt1.Z);
   CloseRgn(tempRgn);
   FillRgn(tempRgn, white);

   OpenRgn;
   MoveTo3D(pt1.X, pt1.Y, pt2.Z); { top face, z=z2 }
   LineTo3D(pt1.X, pt2.Y, pt2.Z);
   LineTo3D(pt2.X, pt2.Y, pt2.Z);
   LineTo3D(pt2.X, pt1.Y, pt2.Z);
   LineTo3D(pt1.X, pt1.Y, pt2.Z);
   CloseRgn(tempRgn);
   FillRgn(tempRgn, gray);

   OpenRgn;
   MoveTo3D(pt2.X, pt1.Y, pt1.Z); { right face, x=x2 }
   LineTo3D(pt2.X, pt1.Y, pt2.Z);
   LineTo3D(pt2.X, pt2.Y, pt2.Z);
   LineTo3D(pt2.X, pt2.Y, pt1.Z);
   LineTo3D(pt2.X, pt1.Y, pt1.Z);
   CloseRgn(tempRgn);
   FillRgn(tempRgn, black);

   PenPat(white);
   MoveTo3D(pt2.X, pt2.Y, pt2.Z); { outline right }
   LineTo3D(pt2.X, pt2.Y, pt1.Z);
   LineTo3D(pt2.X, pt1.Y, pt1.Z);
   PenNormal;

   DisposeRgn(tempRgn);
END;

PROCEDURE MakeBox;
LABEL 1;
VARmyBox: Box3D;
 i, j, h, v: INTEGER;
 p1, p2: Point3D;
 myRect: Rect;
 testRect: Rect;
BEGIN
   p1.x := FixRatio((Random mod 70 - 15), 1);
   p1.y := FixRatio((Random mod 70 - 10), 1);
   p1.z := 0;

   p2.x := p1.x + FixRatio((10 + ABS(Random) MOD 30), 1);
   p2.y := p1.y + FixRatio((10 + ABS(Random) MOD 45), 1);

   p2.z := p1.z + FixRatio((10 + ABS(Random) MOD 35), 1);

   { reject box if it intersects one already in list }
   SetRect(myRect, HiWord(p1.x), HiWord(p1.y), HiWord(p2.x), HiWord(p2.y));

   FOR i := 0 TO nBoxes - 1 DO BEGIN
      WITH boxArray[i] DO
  SetRect(testRect, 
          HiWord(pt1.x), 
  HiWord(pt1.y), 
  HiWord(pt2.x),
          HiWord(pt2.y));
      InSetRect(testRect, -1, -1);
      IF SectRect(myRect, testRect, testRect) THEN goto 1
      END;

   myBox.pt1 := p1;
   myBox.pt2 := p2;

   { calc midpoint of box and its distance from the eye }
   i := 0;
   boxArray[nBoxes].pt1 := myBox.pt1; { sentinel }
   boxArray[nBoxes].pt2 := myBox.pt2;

   WHILE
   ((myBox.pt1.y > boxArray[i].pt2.y) AND (myBox.pt2.y > boxArray[i].pt1.y)) 
OR
   ((myBox.pt1.x < boxArray[i].pt2.x) AND (myBox.pt2.x < boxArray[i].pt1.x)) 
DO
      inc(i); { insert in order of dist }
   FOR j := nBoxes DOWNTO i + 1 DO boxArray[j] := boxArray[j - 1];
   boxArray[i] := myBox;
   inc(nBoxes);
1: 
END;

BEGIN { main program }
   FlushEvents(everyEvent, 0);
   InitGraf(@thePort);
   InitCursor;
   HideCursor;
   OpenPort(@myPort);
   Open3DPort(@myPort3D);

   { put the image in this rect }
   ViewPort(myPort.portRect);
   
   { aim the camera into 3D space }   
   LookAt(FixRatio(-100, 1), 
          FixRatio(75, 1), 
   FixRatio(100, 1),
          FixRatio(-75, 1)); 

   { choose lens focal length }
   ViewAngle(FixRatio(30, 1)); 
   Identity;
   Roll(FixRatio(20, 1));
   Pitch(FixRatio(70, 1)); { roll and pitch the plane }

   REPEAT
      nBoxes := 0;
      REPEAT
         MakeBox
      UNTIL nBoxes=boxCount;

      PenPat(white);
      BackPat(black);
      EraseRect(myPort.portRect);

      FOR i := -10 TO 10 DO BEGIN
         MoveTo3D(FixRatio(i*10, 1), FixRatio(-100, 1), 0);
         LineTo3D(FixRatio(i*10, 1), FixRatio(100, 1), 0);
         END;

      FOR i := -10 TO 10 DO BEGIN
         MoveTo3D(FixRatio(-100, 1), FixRatio(i*10, 1), 0);
         LineTo3D(FixRatio(100, 1), FixRatio(i*10, 1), 0);
         END;

      FOR i := nBoxes-1 DOWNTO 0 DO 
         DrawBrick(boxArray[i].pt1,boxArray[i].pt2);

   UNTIL OSEventAvail(keyOrMouse, dummy);
END.
 

Community Search:
MacTech Search:

Software Updates via MacUpdate

BusyCal 3.7.2 - Powerful calendar app wi...
BusyCal is the powerful, flexible, reliable calendar app for macOS. It's packed with time-saving features and compatible with all leading cloud services including iCloud, Google, Exchange and more.... Read more
BusyContacts 1.4.2 - Fast, efficient con...
BusyContacts is a contact manager for OS X that makes creating, finding, and managing contacts faster and more efficient. It brings to contact management the same power, flexibility, and sharing... Read more
iShowU Instant 1.3.0 - Full-featured scr...
iShowU Instant gives you real-time screen recording like you've never seen before! It is the fastest, most feature-filled real-time screen capture tool from shinywhitebox yet. All of the features you... Read more
Capo 3.8 - Slow down and learn to play y...
Capo lets you slow down your favorite songs so you can hear the notes and learn how they are played. With Capo, you can quickly tab out your songs atop a highly-detailed OpenCL-powered spectrogram... Read more
Viber 11.7.0 - Send messages and make fr...
Viber lets you send free messages and make free calls to other Viber users, on any device and network, in any country! Viber syncs your contacts, messages and call history with your mobile device, so... Read more
Drive Genius 5.3.1 - $79.00
Drive Genius features a comprehensive Malware Scan. Automate your malware protection. Protect your investment from any threat. The Malware Scan is part of the automated DrivePulse utility. DrivePulse... Read more
CorelDRAW 21.2.0.708 - Graphic design so...
CorelDRAW - professional graphic design software for vector illustration, layout, and so much more. Get started quickly and easily with a wealth of intuitive tools, built-in learning materials,... Read more
Navicat Premium Essentials 12.1.27 - Pro...
Navicat Premium Essentials is a compact version of Navicat which provides basic and necessary features you will need to perform simple administration on a database. It supports the latest features... Read more
OmniFocus 3.4.3 - GTD task manager with...
OmniFocus is an organizer app. It uses projects to organize tasks naturally, and then add tags to organize across projects. Easily enter tasks when you’re on the go, and process them when you have... Read more
Microsoft OneNote 16.30 - Free digital n...
OneNote is your very own digital notebook. With OneNote, you can capture that flash of genius, that moment of inspiration, or that list of errands that's too important to forget. Whether you're at... Read more

Latest Forum Discussions

See All

Breakout: Dark Prison is a fast-paced ac...
Breakout: Dark Prison is an action RPG from LaterSoft. Set in the aftermath of a deadly virus outbreak your daughter has been taken from you because she has an immunity to the illness in her DNA. Not being a fan of experimentation on children –... | Read more »
Apple Arcade in review
This weekend, Apple Arcade will officially be one month old. That means anyone who signed up for the free trial on day one has a decision to make: Stick with the service and shell out $5 a month, or cancel and go about your merry way. | Read more »
Alluris is a choose-your-own adventure g...
Alluris is an RPG that the developer's are calling a swipe-your-own adventure game. This is because the game incorporates a Reigns-style - swiping left or right - selection mechanic to make all the decisions you'd usually expect to make across... | Read more »
Hello Hero All Stars receives update wit...
The first Hello Hero game hit global platforms in 2013 and proved a huge success, with developer Fincon adding two more entries to this popular series of casual RPG games since. Released in June this year, Hello Hero All Stars brings many of the... | Read more »
Zombieland: Double Tapper, a cartoon idl...
Zombieland: Double Tapper is the idle RPG tie-in to the upcoming Zombieland: Double Tap. Oddly, it's one of two different Zombieland games launching today, with the other being the Switch title Zombieland: Double Tap - Road Trip. [Read more] | Read more »
Rusty Lake's The White Door launche...
Rusty Lake and Second Maze's intriguing point-and-click adventure game, The White Door, is now up for pre-order on the App Store. This one sees you playing as Robert Hill, a mental health patient who is suffering from severe memory loss. The game... | Read more »
Hellrule is an auto-runner inspired by G...
Hellrule is an upcoming auto-runner game from independent developer Pedrocorp where players will take control of a dapperly dressed gentlemen who comes equipped with a razor-sharp umbrella for slicing up his foes. The game will be available for... | Read more »
Grobo is a gravity bending puzzle platfo...
Grobo is a 2D puzzle platformer that marks the first release from developers Hot Chocolate Games. You'll find yourself manipulating gravity as you make your through this title that's available now for iOS and Android. [Read more] | Read more »
Adrenaline, Compulsive Entertainment’s h...
Compulsive Entertainment’s high-octane arcade racer, Adrenaline, has now made its way to the App Store following a successful launch on Google Play. It’s a ton of challenging, fast-paced fun, boasting easy-to-learn controls and a varied selection... | Read more »
Mario Kart Tour is adding Super Mario Ga...
Earlier today on Twitter, Nintendo announced that Mario Kart Tour is getting a new racer and track. Fans of Super Mario Galaxy will be pleased to hear that Rosalina is the first post-launch character being added, while the iconic Rainbow Road is... | Read more »

Price Scanner via MacPrices.net

11″ WiFi iPad Pros on sale today for up to $2...
Amazon has new 2018 Apple 11″ WiFi iPad Pros in stock today and on sale for up to $250 off Apple’s MSRP. These are the same iPad Pros sold by Apple in its retail and online stores. Be sure to select... Read more
Apple offers clearance 2018 15″ 6-Core MacBoo...
Apple has clearance 2018 15″ 6-Core Touch Bar MacBook Pros, Certified Refurbished, available starting at only $1999. Each model features a new outer case, shipping is free, and an Apple 1-year... Read more
Apple continues to offer refurbished 2019 21″...
Apple has Certified Refurbished 2019 21″ & 27″ iMacs available starting at $929 and up to $350 off the cost of new models. Apple’s one-year warranty is standard, shipping is free, and each iMac... Read more
Verizon offers free iPhone 7 for customers wh...
Verizon is offering a free 32GB iPhone 7 for new or existing customers who open a new line of service, no trade-in required. Cost of the phone is credited to your account monthly for 24 months. The... Read more
13″ 2.4GHz 4-Core MacBook Pros remain availab...
Apple has a full line of Certified Refurbished 2019 13″ 2.4GHz 4-Core Touch Bar MacBook Pros available starting at $1529 and up to $300 off MSRP. Apple’s one-year warranty is included, shipping is... Read more
Lease one iPhone Xs, Xr, or X at Sprint and g...
Purchase an Apple iPhone X, Xr, Xs, or Xs Max at Sprint, and get a 64GB iPhone Xr for free. Requires 2 new lines or 1 upgrade-eligible line and 1 new line. The fine print: “iPhone Xs (64 GB) $37.50/... Read more
How to use your Apple Education discount to s...
Purchase a new MacBook Pro or MacBook Air using Apple’s Education discount, and take up to $200 off MSRP. All teachers, students, and staff of any educational institution with a .edu email address... Read more
Base 2019 13″ 1.4GHz 4-Core MacBook Pro on sa...
Amazon has the new 2019 13″ 1.4GHz/128GB 4-Core Space Gray Touch Bar MacBook Pro on sale for $100 off Apple’s MSRP. This is the same MacBook Pro sold by Apple in its retail and online stores: – 2019... Read more
Save up to $30 on Apple’s AirPods at these re...
Amazon is offering discounts on new 2019 Apple AirPods ranging up to $30 off MSRP. Shipping is free: – AirPods with Charging Case: $144 $15 off MSRP – AirPods with Wireless Charging Case: $169 $30... Read more
Save $15 on Apple Watch Series 5 models on Wa...
Walmart has new Apple Watch Series 5 models on sale for $15 off Apple’s MSRP on their online store. Choose free shipping or free local store pickup (if available). Sale prices for online orders only... Read more

Jobs Board

*Apple* Mobile App Developer - eiWorkflow So...
…eiWorkflow Solutions, LLC is currently looking for a consultant for the following role. Apple Mobile App Developer Tasks the role will be performing: ? Mobile App Read more
Essbase Developer - *Apple* - Theorem, LLC...
Job Summary Apple is seeking an experienced, detail-minded Essbase developer to join our worldwide business development and strategy team. If you are someone who Read more
Best Buy *Apple* Computing Master - Best Bu...
**738230BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Store Associates **Location Number:** 000233-Almeda-Store **Job Description:** The Core Read more
Best Buy *Apple* Computing Master - Best Bu...
**738182BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Sales **Location Number:** 000036-Independence MO-Store **Job Description:** **What Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**741450BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Location Number:** 000168-Mentor-Store **Job Description:** At Best Buy, our Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.