Maybe because you are working directly on the instances? Have you tried to use the copy of the center position vector instead?

Arghhh.. i just found it out while debugging! Yes, now it works! Damnnn, I forgot that tempVec is an instance which is saved in the mentioned ArrayList.

The effect now looks great! I can't wait for releasing this!

THANKS!!!
Marlon

Just multiply the SimpleVector with the matrix returned from Object3D.getWorldTransformation().

Mhhh.. in my case this doesn't seem to work.

In practise I want to add Particles to an item, the character of my game is wearing in his hand. To be even more concrete I want to make a torch which is emitting fire particles.
Because the character (and so the item) is moving while attacking or walking I need to look about the center point of the items mesh at each keyframe.
So I made a list (you already gave me some helpful tipps, egon) and added those center points to it.
With getCenterPosition() I receive the actual position.
Unfortunatly this position is in object space and I need the coordinates in world space.

Here is my code:
float cx=0, cy=0, cz=0;
SimpleVector tmpVec=obj3D.getCenterPosition();
if(tmpVec!=null) {
tmpVec.matMul(obj3D.getWorldTransformation());
cx=tmpVec.x*obj3D.getScale();
cy=tmpVec.y*obj3D.getScale();
cz=tmpVec.z*obj3D.getScale();
}
particlePosition = new SimpleVector(obj3D.getTranslation().x+cx, obj3D.getTranslation().y+cy, obj3D.getTranslation().z+cz);

Although mathematic was my intensive course at shool the third dimension is always bringing confusion to my brain. 
It would be great if somebody could help me.

Hi there!

I have a parent object with world position (ie. 1,0,0) and a child object with relative position to the parent object (ie. 2,0,0). This means the world position of the child object in this case would become (3,0,0), because it's relative to the parent object's space. I would like to retrieve the world position (ie. 3,0,0) of the child.
Currently the child only knows it's relative position.
How can I achieve this? What functions I have to use to calculate it?

Thanks in advance!
Marlon

I suggest you to export your 3D model as a md2 file with the help of blender.
You will then need a md2.txt file, where you give information about the object and its keyframes.
For example if you have a character, which has 2 animations (move=4 frames and idle=2 frames) your file should look like this:
# MD2 Frame Name List
"nothing" 1
"move" 4
"idle" 2

I am using
obj.clearTranslation();
obj.translate(....);
as well and the object gets placed correctly.

But there seem to be a problem with child objects. If our object gets a child (obj.addChild(child)) the child isn't linked correctly with its parent.
Is there a way to solve this problem when doing absolute position?

http://www.jpct.net/download.html
I just installed the latest JDK and the latest version of JPCT (upper link, click on JPCT) on my new computer.
I put the windows native lwjgl.dll into the project folder.

I have bought a new laptop with Windows 7 64bit and installed the Java 7 JDK.
When trying to execute the program it crashes.
After installing eclipse and testing in this programming environment, it crashes again without giving error messages.
So I decided to make a new Project and paste/copy Advanced Example from the JPCT Wiki to test it.
There it crashes, too but the following log gets created in the Directory of the Project:

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x0035fe6e, pid=2188, tid=1976
#
# JRE version: 7.0_01-b08
# Java VM: Java HotSpot(TM) Client VM (21.1-b02 mixed mode, sharing windows-x86 )
# Problematic frame:
# C  0x0035fe6e
#
# Failed to write core dump. Minidumps are not enabled by default on client versions of Windows
#
# If you would like to submit a bug report, please visit:
#   http://bugreport.sun.com/bugreport/crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#

---------------  T H R E A D  ---------------

Current thread (0x004d9800):  JavaThread "main" [_thread_in_native, id=1976, stack(0x00fc0000,0x01010000)]

siginfo: ExceptionCode=0xc0000005, reading address 0x055cb000

Registers:
EAX=0x0c07d350, EBX=0x05060000, ECX=0x0000044c, EDX=0x000001b4
ESP=0x0100ebbc, EBP=0x00000000, ESI=0x055cb000, EDI=0x00000000
EIP=0x0035fe6e, EFLAGS=0x00010206

Top of Stack: (sp=0x0100ebbc)
0x0100ebbc:   06230020 05060000 00000600 0100ec04
0x0100ebcc:   68792974 05060000 0c06e2b0 00000000
0x0100ebdc:   00000600 05060000 06230020 00000000
0x0100ebec:   05087198 05060000 06230020 00000000
0x0100ebfc:   0c06e2b0 00000000 0100ec24 68792c02
0x0100ec0c:   00060000 00000004 00000000 00000600
0x0100ec1c:   00000004 05060000 0100ec48 67fcb6e7
0x0100ec2c:   05060000 00000004 00000000 00000600

Instructions: (pc=0x0035fe6e)
0x0035fe4e:   01 00 00 8d 34 ce 8b 3e 8b 6e 04 89 78 28 89 68
0x0035fe5e:   2c 8b 35 d0 79 08 05 8b b6 bc 01 00 00 8d 34 ce
0x0035fe6e:   8b 3e 8b 6e 04 89 78 30 89 68 34 83 c0 38 41 4a
0x0035fe7e:   0f 85 4e ff ff ff 5f 5e 5b 5d c3 00 00 00 00 00


Register to memory mapping:

EAX=0x0c07d350 is an unknown value
EBX=0x05060000 is an unknown value
ECX=0x0000044c is an unknown value
EDX=0x000001b4 is an unknown value
ESP=0x0100ebbc is pointing into the stack for thread: 0x004d9800
EBP=0x00000000 is an unknown value
ESI=0x055cb000 is an unknown value
EDI=0x00000000 is an unknown value


Stack: [0x00fc0000,0x01010000],  sp=0x0100ebbc,  free space=314k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C  0x0035fe6e

[error occurred during error reporting (printing native stack), id 0xc0000005]

Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
J  org.lwjgl.opengl.GL11.nglDrawArrays(IIIJ)V
J  com.threed.jpct.CompiledInstance.render(ILcom/threed/jpct/GLBase;Ljava/nio/FloatBuffer;[FZLcom/threed/jpct/Camera;[[FZ[Ljava/lang/Object;)V
J  com.threed.jpct.GLRenderer.drawVertexArray(Lcom/threed/jpct/VisList;IILcom/threed/jpct/FrameBuffer;Lcom/threed/jpct/World;)V
J  com.threed.jpct.World.draw(Lcom/threed/jpct/FrameBuffer;ZIII)V
J  com.threed.jpct.util.ShadowHelper.updateShadowMap()V
j  AdvancedExample.gameLoop()V+141
j  AdvancedExample.main([Ljava/lang/String;)V+17
v  ~StubRoutines::call_stub

---------------  P R O C E S S  ---------------

Java Threads: ( => current thread )
  0x04d6fc00 JavaThread "AWT-Windows" daemon [_thread_in_native, id=3156, stack(0x05240000,0x05290000)]
  0x04d6c800 JavaThread "Java2D Disposer" daemon [_thread_blocked, id=3928, stack(0x050c0000,0x05110000)]
  0x0119bc00 JavaThread "Service Thread" daemon [_thread_blocked, id=2284, stack(0x04af0000,0x04b40000)]
  0x01197000 JavaThread "C1 CompilerThread0" daemon [_thread_blocked, id=1792, stack(0x04aa0000,0x04af0000)]
  0x01195c00 JavaThread "Attach Listener" daemon [_thread_blocked, id=3732, stack(0x04780000,0x047d0000)]
  0x01192800 JavaThread "Signal Dispatcher" daemon [_thread_blocked, id=3228, stack(0x00f70000,0x00fc0000)]
  0x0118ac00 JavaThread "Finalizer" daemon [_thread_blocked, id=3180, stack(0x04880000,0x048d0000)]
  0x01186000 JavaThread "Reference Handler" daemon [_thread_blocked, id=3252, stack(0x04900000,0x04950000)]
=>0x004d9800 JavaThread "main" [_thread_in_native, id=1976, stack(0x00fc0000,0x01010000)]

Other Threads:
  0x01183800 VMThread [stack: 0x047f0000,0x04840000] [id=3688]
  0x011ae400 WatcherThread [stack: 0x04ce0000,0x04d30000] [id=2256]

VM state:not at safepoint (normal execution)

VM Mutex/Monitor currently owned by a thread: None

Heap
 def new generation   total 18432K, used 9931K [0x243e0000, 0x257e0000, 0x29930000)
  eden space 16384K,  60% used [0x243e0000, 0x24d87fc8, 0x253e0000)
  from space 2048K,   2% used [0x255e0000, 0x255eb020, 0x257e0000)
  to   space 2048K,   0% used [0x253e0000, 0x253e0000, 0x255e0000)
 tenured generation   total 57260K, used 45002K [0x29930000, 0x2d11b000, 0x343e0000)
   the space 57260K,  78% used [0x29930000, 0x2c522be8, 0x2c522c00, 0x2d11b000)
 compacting perm gen  total 12288K, used 1726K [0x343e0000, 0x34fe0000, 0x383e0000)
   the space 12288K,  14% used [0x343e0000, 0x3458fb78, 0x3458fc00, 0x34fe0000)
    ro space 10240K,  42% used [0x383e0000, 0x3881c7b0, 0x3881c800, 0x38de0000)
    rw space 12288K,  53% used [0x38de0000, 0x39458210, 0x39458400, 0x399e0000)

Code Cache  [0x02770000, 0x02a80000, 0x04770000)
 total_blobs=860 nmethods=593 adapters=200 free_code_cache=29635Kb largest_free_block=30346944

Dynamic libraries:
0x01340000 - 0x0136f000 C:\Program Files (x86)\Java\jre7\bin\javaw.exe
0x77190000 - 0x77310000 C:\Windows\SysWOW64\ntdll.dll
0x74e20000 - 0x74f20000 C:\Windows\syswow64\kernel32.dll
0x75240000 - 0x75286000 C:\Windows\syswow64\KERNELBASE.dll
0x768a0000 - 0x76940000 C:\Windows\syswow64\ADVAPI32.dll
0x766b0000 - 0x7675c000 C:\Windows\syswow64\msvcrt.dll
0x750d0000 - 0x750e9000 C:\Windows\SysWOW64\sechost.dll
0x76a40000 - 0x76b30000 C:\Windows\syswow64\RPCRT4.dll
0x74d00000 - 0x74d60000 C:\Windows\syswow64\SspiCli.dll
0x74cf0000 - 0x74cfc000 C:\Windows\syswow64\CRYPTBASE.dll
0x76940000 - 0x76a40000 C:\Windows\syswow64\USER32.dll
0x76760000 - 0x767f0000 C:\Windows\syswow64\GDI32.dll
0x75290000 - 0x7529a000 C:\Windows\syswow64\LPK.dll
0x76270000 - 0x7630d000 C:\Windows\syswow64\USP10.dll
0x72350000 - 0x724ee000 C:\Windows\WinSxS\x86_microsoft.windows.common-controls_6595b64144ccf1df_6.0.7600.16385_none_421189da2b7fabfc\COMCTL32.dll
0x752a0000 - 0x752f7000 C:\Windows\syswow64\SHLWAPI.dll
0x75130000 - 0x75190000 C:\Windows\system32\IMM32.DLL
0x76cc0000 - 0x76d8c000 C:\Windows\syswow64\MSCTF.dll
0x74b80000 - 0x74bb6000 C:\Windows\SysWOW64\nvinit.dll
0x0f000000 - 0x0f006000 C:\Program Files (x86)\NVIDIA Corporation\CoProcManager\_etoured.dll
0x747a0000 - 0x747dd000 C:\Program Files (x86)\NVIDIA Corporation\CoProcManager\nvd3d9wrap.dll
0x76510000 - 0x766ad000 C:\Windows\syswow64\SETUPAPI.dll
0x76c90000 - 0x76cb7000 C:\Windows\syswow64\CFGMGR32.dll
0x74d90000 - 0x74e1f000 C:\Windows\syswow64\OLEAUT32.dll
0x76b30000 - 0x76c8c000 C:\Windows\syswow64\ole32.dll
0x75190000 - 0x751a2000 C:\Windows\syswow64\DEVOBJ.dll
0x74760000 - 0x7479b000 C:\Program Files (x86)\NVIDIA Corporation\CoProcManager\nvdxgiwrap.dll
0x6a540000 - 0x6a5fe000 C:\Program Files (x86)\Java\jre7\bin\msvcr100.dll
0x6d1b0000 - 0x6d4d1000 C:\Program Files (x86)\Java\jre7\bin\client\jvm.dll
0x71e90000 - 0x71e97000 C:\Windows\system32\WSOCK32.dll
0x750f0000 - 0x75125000 C:\Windows\syswow64\WS2_32.dll
0x75510000 - 0x75516000 C:\Windows\syswow64\NSI.dll
0x71e50000 - 0x71e82000 C:\Windows\system32\WINMM.dll
0x74fa0000 - 0x74fa5000 C:\Windows\syswow64\PSAPI.DLL
0x71e40000 - 0x71e4c000 C:\Program Files (x86)\Java\jre7\bin\verify.dll
0x71e20000 - 0x71e40000 C:\Program Files (x86)\Java\jre7\bin\java.dll
0x71e00000 - 0x71e13000 C:\Program Files (x86)\Java\jre7\bin\zip.dll
0x6a3f0000 - 0x6a532000 C:\Program Files (x86)\Java\jre7\bin\awt.dll
0x746e0000 - 0x74760000 C:\Windows\system32\uxtheme.dll
0x738f0000 - 0x73903000 C:\Windows\system32\dwmapi.dll
0x6bcb0000 - 0x6bcd5000 C:\Program Files (x86)\Java\jre7\bin\jpeg.dll
0x10000000 - 0x10073000 E:\workspace\AdvancedExample\lwjgl.dll
0x6d950000 - 0x6da18000 C:\Windows\system32\OPENGL32.dll
0x6dbb0000 - 0x6dbd2000 C:\Windows\system32\GLU32.dll
0x6c4f0000 - 0x6c5d7000 C:\Windows\system32\DDRAW.dll
0x6c6b0000 - 0x6c6b6000 C:\Windows\system32\DCIMAN32.dll
0x74c20000 - 0x74c29000 C:\Windows\system32\VERSION.dll
0x74d60000 - 0x74d8d000 C:\Windows\syswow64\WINTRUST.dll
0x74fb0000 - 0x750cc000 C:\Windows\syswow64\CRYPT32.dll
0x75390000 - 0x7539c000 C:\Windows\syswow64\MSASN1.dll
0x67e60000 - 0x69085000 C:\Windows\system32\nvoglv32.DLL
0x75520000 - 0x76169000 C:\Windows\syswow64\SHELL32.dll
0x63560000 - 0x635d9000 C:\Windows\system32\mscms.dll
0x71f30000 - 0x71f47000 C:\Windows\system32\USERENV.dll
0x73640000 - 0x7364b000 C:\Windows\system32\profapi.dll
0x6dab0000 - 0x6dae8000 C:\Windows\system32\icm32.dll
0x08d40000 - 0x09187000 C:\Windows\system32\igd10umd32.dll
0x645c0000 - 0x646ab000 C:\Windows\system32\dbghelp.dll

VM Arguments:
jvm_args: -Dfile.encoding=Cp1252
java_command: AdvancedExample
Launcher Type: SUN_STANDARD

Environment Variables:
PATH=C:/Program Files (x86)/Java/jre7/bin/client;C:/Program Files (x86)/Java/jre7/bin;C:/Program Files (x86)/Java/jre7/lib/i386;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;D:\Program Files\eclipse;
USERNAME=Marlon
OS=Windows_NT
PROCESSOR_IDENTIFIER=Intel64 Family 6 Model 37 Stepping 5, GenuineIntel



---------------  S Y S T E M  ---------------

OS: Windows 7 , 64 bit Build 7600

CPU:total 4 (2 cores per cpu, 2 threads per core) family 6 model 37 stepping 5, cmov, cx8, fxsr, mmx, sse, sse2, sse3, ssse3, sse4.1, sse4.2, popcnt, ht

Memory: 4k page, physical 3986864k(2259632k free), swap 7971832k(5828660k free)

vm_info: Java HotSpot(TM) Client VM (21.1-b02) for windows-x86 JRE (1.7.0_01-b08), built on Oct  3 2011 02:11:36 by "java_re" with unknown MS VC++:1600

time: Thu Nov 24 18:25:15 2011
elapsed time: 6 seconds

What does this mean? Does JPCT have problems with Win 7 or a 64 Bit OS?
I tried other programs (for example some demos from Ardor3D) and all runs fine.

Ah, alles klar, danke!
Einen Pool zu erstellen ist natürlich kein Problem, und mit setIntensity() und setPosition() kann man ja schliesslich die Haupteigenschaften des Lichts neu setzen.