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#ifndef lint |
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static const char RCSid[] = "$Id: m_alias.c,v 2.9 2018/02/16 18:37:51 greg Exp $"; |
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#endif |
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/* |
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* Handler for modifier alias |
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*/ |
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|
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#include "copyright.h" |
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|
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#include "ray.h" |
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#include "otypes.h" |
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#include "rtotypes.h" |
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#include "otspecial.h" |
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|
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/* |
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* If the alias has a single string argument, it's the |
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* name of the target modifier, and we must substitute the |
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* target and its arguments in place of this alias. The |
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* only difference is that we use our modifier rather than |
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* theirs. |
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* If the alias has no string arguments, then we simply |
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* pass through to our modifier as if we weren't in the |
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* chain at all. |
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*/ |
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|
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int |
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m_alias( /* transfer shading to alias target */ |
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OBJREC *m, |
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RAY *r |
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) |
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{ |
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OBJECT aobj; |
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OBJREC *aop; |
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OBJREC arec; |
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int rval; |
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/* straight replacement? */ |
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if (!m->oargs.nsargs) |
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return(rayshade(r, m->omod)); |
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|
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aop = m; /* else look it up */ |
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aobj = objndx(aop); |
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do { /* follow entire alias trail */ |
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if (!aop->oargs.nsargs) |
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aobj = aop->omod; |
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else if (aop->oargs.nsargs == 1) |
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aobj = lastmod(aobj, aop->oargs.sarg[0]); |
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else |
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objerror(aop, INTERNAL, "bad # string arguments"); |
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if (aobj < 0) |
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objerror(aop, USER, "bad reference"); |
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aop = objptr(aobj); |
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} while (aop->otype == MOD_ALIAS); |
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/* copy struct */ |
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arec = *aop; |
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/* substitute modifier */ |
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arec.omod = m->omod; |
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/* irradiance hack */ |
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if (do_irrad && !(r->crtype & ~(PRIMARY|TRANS)) && raytirrad(&arec, r)) |
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return(1); |
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/* replacement shader */ |
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rval = (*ofun[arec.otype].funp)(&arec, r); |
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/* save allocated struct */ |
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if (arec.os != aop->os) { |
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if (aop->os != NULL) /* should never happen */ |
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free_os(aop); |
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aop->os = arec.os; |
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} |
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return(rval); |
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} |