Vega  FAQ's

51   What 3d model file formats does Vega Support  

 

Vega for NT directly supports the following 3D file format
flt   fst	MultiGen's OpenFlight v14 and above   MultiGen's fast binary file format
Vega for Irix supports the following 3D file format ( the same as OpenGL Performer 2.2.x)
flt pfa pfb dxf 3ds obj dwb lsa lsb bin bpoly byu gds gfo im irtp iv m medit nff post phd poly pts ptu s1k sgf sgo spf sponge star stla stlb sv tri unc	MultiGen OpenFlight v14 and above OpenGL Performer ASCII format OpenGL Performer fast binary format AutoDesk AutoCAD ASCII format AutoDesk 3DStudio binary data ( OLD!!!!!) Wavefront Technologies data format Coryphaeus Software Designer's Workbench Lightscape radiosity solutions (ASCII) Lightscape radiosity solutions (binary) Minor SGI format used by powerflip Side Effects Software PRISMS binary Brigham Young University CAD/FEA data McDonnell-Douglas GDS things data Minor SGI format (radiosity output) Minor SGI format (OpenGL Performer example) AAI/Graphicon Interactive Real-Time PHIGS SGI Open Inventor/VRML 1.0 University of Washington mesh data Medit Productions medit modeling tool Eric Haines' ray tracing test data format Minor SGI format (example gridded terrain loader) Minor SGI format (polyhedra) Side Effects Software PRISMS ASCII data University of Washington point data Minor SGI format (OpenGL Performer example) U.S. Army SIMNET databases (Texas Instruments) U.S. Navy standard graphics format Minor SGI format U.S. Navy simple polygon format Sierpinski sponge 3D fractal generator Yale University compact star chart data 3D Structures Stereolithography (ASCII) 3D Structures Stereolithography (binary) Format of John Kichury's i3dm modeler University of Minnesota Geometry Center data University of North Carolina data

52    How to I use 3ds, Dxf, 3d Max files in Vega

You need a program that can convert these files in to OpenFlight format. A very good program for this is PolyTran's from Okino www.okino.com ( see Okino for supported file formats http://www.okino.com/conv/filefrmt_3dimport.htm)

Also MultiGen Creator can import certain type of 3d File formats
 

53   Can I use Borland C++ Builder with Vega NT

Vega NT is only supported on Microsoft Visual Studio ( Service pack 5 and above)

A couple of people have had some success in using Borland's C++ Builder, here's the details of what they have done, I cannot say if this will work or not

1) Convert all lib files to Borland compatible.

This bat file (mycoff2omf.bat) will convert a lib file to Borland format, using the coff2omf routine supplied with C++:

@echo off

Coff2omf -q %1 x.lib >> convertlog.txt

if errorlevel 1 goto :fail

copy %1 orig_lib

copy x.lib %1

echo File %1 copied and converted >> convertlog.txt

goto :EOF

:fail

echo Error in file %1, not converted >> convertlog.txt

The Coff2omf routine is found in the Borland executable directory, and should be in the path.

This bat file (convertAll.bat) uses the first bat file to convert all lib files in the Vega lib directory. The easiest way to do this is to put both bat files in the Vega directory.

cd "c:\program files\paradigm\Vega\lib"

mkdir orig_lib

attrib -r *.lib 

for %%f in (*.lib) do MyCoff2omf %%f

del x.lib
 

2) You have to modify the jlu.h file to eliminate a define of ptrdiff_t already defined by Borland: 

#ifndef _BORLAND

typedef int ptrdiff_t;

#endif
 

3) In you Borland project, under Project | Options | Directories/Conditionals in the Conditionals Edit box, enter:

_DLL;_BORLAND;WIN32

 

54   Can I use Vega in MFC

Yes you can use Microsoft's Foundation Class library with Vega NT :

Vega ships with a simple example project, see <%>Sample\Vega\pguide\ch03\MFCVega
 

55  How do I get debug information with MFC and Vega NT

Yes you can get the debug out in an MFC application that is normally sent to the console window in Vega NT

This can be done in a couple of ways :
 

• You can send the output to the debugger window of Visual Studio

In your Vega directories search for "EditPlatform.bat" and run the batch file

Then check the USE_OUTPUTDEBUGSTRING box and this will allow out put to the Visual Studio debug window.

 

• You can  use vgCreateConsole();

• Or you could  create your own console using AllocConsole();

 

 

Code :
--	if( AllocConsole() ){       //    // Now we have to pipe the all Vega output to the new console window                    //       int outHandle = _open_osfhandle( ( long );        GetStdHandle( STD_OUTPUT_HANDLE ), _O_TEXT  );      FILE *outFile = _fdopen( outHandle, "w"  );      *stdout = *outFile;      setvbuf( stdout, NULL, _IONBF, 0 );      }

 

56   Can I use Vega in a container such as ActiveX  

Yes and no is the answer to using Vega NT in an ActiveX container. While it is certainly possible to use Vega in an ActiveX container is has one inherent and very limiting factor. Vega NT gets its heritage from Vega Irix and OpenGL Performer, which are designed to be use as stand alone application both call exit(0) during there shutdown process.

Vega and Performer both use large amounts of memory and create their own memory pool and manager. This memory pool other major components of Vega and Performer are only correctly freed when the program Exits. This means that they are not re-entrant  meaning you cannot simply  initialise start stop and repeat the initialise, start, stop Vega or Performer again by default they both call Exit(0) during their shutdown process.
 

57   Is there a COM interface for VegaNT

No there is no COM interface for VegaNT, ( Vega Irix does have a TCL/TK interface )

 

58   Can I use Vega with Tcl/TK  

 

Yes you can use Tcl/TK with Vega, vgTcl provides Tcl//TK bindings for Vega and  was created by the talented Mike Weiblen.

vgTcl was distributed with Vega on the installation CD's as a vgGift, which means it was officially unsupported by MultiGen-Paradigm although it was maintained by Mike Weiblen.

 

59   What is vgTcl

vgTcl provides Tcl//TK bindings to Vega, vgTcl was distributed with Vega on the installation CD's as a vgGift,

Further details on vgTcl can be found on Mike Weiblen's web site vgTcl readme
 

60   How do I get a Vega class property

 

With Vega there are 2 ways to get properties from Vega Class instances

 

• Firstly using the vgCommon  function   "float  vgGetProp( vgCommon *handle, int which )";

For example to retrieve the state of a vgChannel we call int state = (int) vgGetProp( vgGetChan(0), VGCOMMON_ENABLED );

See the individual vgClasses man pages for which properties can be retrieved using vgGetProp

• Secondly using the class specific functions where the property cannot be returned as a float

For example to retrieve the current filed of view form a channel we call

 

Code :
--	float h = 0.0f; float v = 0.0f; vgGetChanFOV( vgGetChan(0), &h, &v  );

 

See the individual vgClasses man pages for what vgGetxxx functions are available
 

61   How do I change a Vega class property

With Vega there are 2 possible ways to change properties for Vega Class instances.

 

• Firstly using the vgCommon function   "void  vgProp( vgCommon *handle, int which, float prop )";

For example to change the state of a vgChannel we call  vgProp( vgGetChan(0), VGCOMMON_ENABLED, VG_ON );

See the vgClasses individual man pages for which properties can be changed using vgProp

• Secondly using the class specific functions where the property cannot be set with float or int

For example to  the current filed of view for  a channel we call

 

Code :
--	float h = 45.0f; float v = -1.0f; vgChanFOV( vgGetChan(0), h, v  );

See the individual vgClasses man pages for what vgClassxxx set functions are available
 

62  How do I set a property on vgSystem before

See vgCommon for more details; vgClassProp and vgGetClassProp are very similar to their related functions (vgProp and vgGetProp), but they set and return class properties. Class properties are those which exist at the class level. In other words there is one for each class, as opposed to one for each class instance.
 

63  How to find a vgObject

To find a vgObject is pretty straight forward, there are two ways to get a pointer to a specific vgObject

 

• Firstly you can find an vgObject by name using vgFindObj( "objectName");,Note the text search is case sensitive, also if you have vgObject with same name the first one in Vega internal list will be returned

• Secondly you can get a vgObject by using vgGetObj( int index)  if you know the index. Note that if you delete a vgObject then indices of other object may change.

See vgObject man pages further details on the vgObject Class

64  How do I delete an vgObject

To delete a vgObject simply use the vgCommon function vgDelete( vgCommon *handle ); For example :

Code :
--	vgObject *obj = vgGetObj( 0 ); vgDelete( obj );

 

Note before you attempt to use vgDelete() you must first ensure that the vgObject is removed from all association with vgScene, vgPlayer, etc.

See vgObject man pages further details on the vgObject Class

65   How can I check if a vgObject is within my FOV

The following pseudo code show you how to test is a vgObject is within the current Field of View:

 

• get the pfNode* from the vgObject with vgGetPfNode (see the vgObject man page)
• get the bounding sphere from the pfNode (see the pfNode man page)
• get the pfChannel from the vgChannel, vgGetChanPfNode (see the vgChannel man    )
• call pfChanContainsSphere( chanPointer, spherePointer)  (see the pfChannel man    )


See the  "How Check if a vgObject is in the FOV" Sample code for further details

See vgObject man pages further details on the vgObject Class

66  How do I create a vgObject in code

To create a new vgObject in code you have to do the following:
 

• Create a new and empty vgDataSet with vgNewDS
• Set the path to the file for the dataset to load with vgName
• Use vgProp to set initial properties on the dataset
• Load the model file using vgLoadDS
• Create a new empty vgObject
• Name the vgObject
• Set the vgObject as dynamic or static with vgProp
• Set the optimisation mode for the object with vgProp
• Set any offset for the object with vpPos
• Associate the vgObject and vgDataSet using vgObjDS
• Now we make the object with vgMakeObj
• Set the Isector mask for the vgObject and its geometry
• Set the representation mask for the vgObject

 

See the  "How to create a vgObject" Sample code for further details

See vgObject man pages further details on the vgObject Class

See vgPart man pages further details on the vgPart Class

See vgDataSet man pages further details on the vgDataSet Class


See vgMotion  man pages further details on the vgMotion Class

See vgCPos man pages further details on the vgCPos Class

67   How do you get the Position of a vgObject

To get the position of a vgObject you need to use a vgPos, something alone the lines of:

Code :
--	vgObject   *obj = NULL; vgPosition *pos = NULL;   float x = 0.0f, y = 0.0f, z = 0.0f; float h = 0.0f, p = 0.0f, r = 0.0f;   // //  Grab a pointer to the object //      obj  = vgGetObj( 0 );   // //  Create a vgPos //      pos  = vgNewPos( );   // //  Retrieve the current position from the object //      vgGetPos( obj, pos );   // //  Now retrieve the position vectors //      vgGetPosVec( pos, &x, &y, &z, &h, &p, &r );   // //  Release the vgPos as where done //      vgDelPos( pos );

See the  "How get the vgObject Position" Sample code for further details

See vgObject man pages further details on the vgObject Class

See vgCPos man pages further details on the vgCPos Class

68   Why does my vgObjects position always 0,0,0

First make sure that your vgObject has actually been added to your vgScene

If the vgObject has been attached to a vgPlayer or your using Vega LADBM then using vgGetPos will return 0,0,0 for your position because this will return the only the local position

To get the position of the vgObject in this instance you need to get the World coordinates rather than the local coordinates thus we need to use vgGetWCSPos rather than the vgGetPos function

See the  "How get the vgObject World Coordinate Position" Sample code for further details

See vgObject man pages further details on the vgObject Class

See vgCPos man pages further details on the vgCPos Class

69    How can I set the position of a vgObject 

Setting the postion of an Object in Vega is unfortunately a little awkward than it needs to be, in that you must first get the objects current position if you   want to update only part of the object translation or rotation. For example:

Code :
--	vgObject   *obj = NULL;   vgPosition *pos = NULL;   float x = 0.0f, y = 0.0f, z = 0.0f; float h = 0.0f, p = 0.0f, r = 0.0f;   // //  Grab a pointer to the object //      obj  = vgGetObj( 0 );   // //  Create a vgPos //      pos  = vgNewPos( );   // //  Retrieve the current position from the object //      vgGetPos( obj, pos );   // //  Now retrieve the position vectors //      vgGetPosVec( pos, &x, &y, &z, &h, &p, &r );   // //  Now update the vectors //      x = x + 10.0f; y = y + 20.0f; z = z + 30.0f;   // //  Now We can Set the position vectors //      vgPosVec( pos, x, y, z, h, p, r );     // //  Now we can finally set the current position for the object //      vgPos( obj, pos );     // //  Release the vgPos as where done //      vgDelPos( pos );

See its a little awkward ;), also not if your doing this alot it would be make sense to create a function and also keep the vgPosition instance around rather than creating and deleting each time ( its faster and stops fragmentation )

See vgObject man pages further details on the vgObject Class

See vgCPos man pages further details on the vgCPos Class

70  How can I find a vgPart in vgObject 

There are two ways to find and retrieve vgParts from a vgObject using the 2 following functions:

 

• vgFindPart
   
• vgFindPartOccurence


vgFindPart finds a named vgPart of an vgObject. If the name is NULL, then the root vgPart of the vgObject is returned. If multiple vgParts within the vgObject have the same name, the first occurrence of that vgPart will be returned if the third argument is set to NULL. To find subsequent occurrences, the third argument should be a pointer to the previous vgPart found.

Code :
--	vgObject *obj = NULL; vgPart   *w1  = NULL;   vgPart   *w2  = NULL; vgPart   *w3  = NULL; vgPart   *w4  = NULL;     // //  Grab a pointer to the object //      obj = vgFindObj( "Blue Car" ); w1 = vgFindPart ( obj, "wheel", NULL ); w2 = vgFindPart ( obj, "wheel", w1 ); w3 = vgFindPart ( obj, "wheel", w2 ); w4 = vgFindPart ( obj, "wheel", w3 );

 

vgFindPartOccurence will also find a named vgPart of an vgObject. If multiple vgParts within the vgObject have the same name, the 'n-th' occurrence of the vgPart can be directly retrieved by setting the third argument to 'n'.

Code :
--	vgObject *obj = NULL; vgPart   *w1  = NULL;   vgPart   *w2  = NULL; vgPart   *w3  = NULL; vgPart   *w4  = NULL;     // //  Grab a pointer to the object //      obj = vgFindObj( "Blue Car" ); w1 = vgFindPartOccurence ( obj, "wheel", 1 ); w2 = vgFindPartOccurence ( obj, "wheel", 2 ); w3 = vgFindPartOccurence ( obj, "wheel", 3 ); w4 = vgFindPartOccurence ( obj, "wheel", 4 );

See vgObject man pages further details on the vgObject Class

See vgPart man pages further details on the vgPart class

 

71  How to Delete a vgPart

Its pretty straight forward to delete a vgPart you simply use vgDelete

Code :
--	vgObject *obj  = NULL;   vgPart   *part = NULL;       // //  Grab a pointer to the object //      obj  = vgFindObj( "my_nice_object" ); part = vgFindPart ( obj, "wheel",