Re: Node Draw Traversal Callbacks
rweyrauch++at++camus.paradigmsim.com
Fri, 6 Dec 1996 08:52:28 -0600
On Dec 6, 6:27am, Bryan Wasileski wrote:
> Subject: Node Draw Traversal Callbacks
> Peformers:
> I seem to be having some difficulty with some assigning pre and post
> node travseral callbacks. I have a class in which a public member is a
> pfNode; the objects created from this class are allocated from shared
> memory. After I initialize the class and it members, I go through the
> member pfnodes and try to assign the pre and post draw traversals. The
> very first pfNode cause the program to dump. The message says that it
> is an illegal instruction. Below is a peice of the code...
>
> for(i=0;i<num_targets;i++)
> gm->mrp_target[i]->obj->setTravFuncs(PFTRAV_DRAW,
> MrpTargetPreDraw,MrpTargetPostDraw);
>
> gm - pointer to the shared memory
> mrp_target[i]->obj - is of type *pfNode.
>
> The pre and post draw functions are:
> MrpTargetPreDraw();
> MrpTargetPostDraw();
>
> .......Here are those function declarations:
>
> void
> MrpTargetPreDraw(pfTraverser *trav, void *data)
> {
> int i,j;
> pfChannel *current_chan = trav->getChan();
>
> pfNode *current_node = trav->getNode();
>
> if(!gm->USE_MRP_OCCLUSSION)
> return;
>
> for(i=0;i<NUM_MRP_CHANNELS;i++)
> if(current_chan == gm->mrp_chan[i])
> {
> MrpChanShareData *chan_data =
> ( MrpChanShareData *)current_chan->getChanData();
> for(j=0;j<TGTIG_NUM_TARGETS;j++)
> if( current_node == gm->mrp_target[chan_data->target_index]->obj
> )
> ClearMRPStencilMask();
> break;
> }
> return;
> }
>
>
> and.....
>
> void
> MrpTargetPostDraw(pfTraverser *trav, void *data)
> {
> int i,j;
> pfChannel *current_chan = trav->getChan();
>
> pfNode *current_node = trav->getNode();
>
> if(!gm->USE_MRP_OCCLUSSION)
> return;
>
> // Check to see if this is an mrp channel
> for(i=0;i<NUM_MRP_CHANNELS;i++)
> if(current_chan == gm->mrp_chan[i])
> {
> MrpChanShareData *chan_data =
> ( MrpChanShareData *)current_chan->getChanData();
> for(j=0;j<TGTIG_NUM_TARGETS;j++)
> if( current_node == gm->mrp_target[chan_data->target_index]->obj
> )
> SetMRPStencilMask();
> break;
> }
> return;
> }
>
>
> I use these pre and post callback to change stencil mask settings....
> This routines are located in the same source file as all the draw and cull
> callbacks for the channels;
> If anyone has any advise or see something wrong, please let me know.
> I really need to have this working. Thanks.
>
> - Bryan Wasileski
> McDonnell Douglas Training Systems
> St. Louis, MO
>
>-- End of excerpt from Bryan Wasileski
Try making the node pre/post draw callbacks static member functions. Use the
pfNode::setTravData function to pass a pointer to the instance you want to
process in the draw callbacks.
Rick
--
Rick Weyrauch voice: (972) 960-2301
Paradigm Simulation Inc. fax: (972) 960-2303
14900 Landmark Blvd., Suite 400 rweyrauch++at++paradigmsim.com
Dallas TX 75240 www.paradigmsim.com
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on Mon Aug 10 1998 - 17:54:06 PDT