open_toontown_panda3d/panda/src/pgraph/renderAttrib.cxx

316 lines
13 KiB
C++

// Filename: renderAttrib.cxx
// Created by: drose (21Feb02)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) 2001, Disney Enterprises, Inc. All rights reserved
//
// All use of this software is subject to the terms of the Panda 3d
// Software license. You should have received a copy of this license
// along with this source code; you will also find a current copy of
// the license at http://www.panda3d.org/license.txt .
//
// To contact the maintainers of this program write to
// panda3d@yahoogroups.com .
//
////////////////////////////////////////////////////////////////////
#include "renderAttrib.h"
#include "bamReader.h"
#include "indent.h"
RenderAttrib::Attribs *RenderAttrib::_attribs = NULL;
TypeHandle RenderAttrib::_type_handle;
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::Constructor
// Access: Protected
// Description:
////////////////////////////////////////////////////////////////////
RenderAttrib::
RenderAttrib() {
if (_attribs == (Attribs *)NULL) {
// Make sure the global _attribs map is allocated. This only has
// to be done once. We could make this map static, but then we
// run into problems if anyone creates a RenderState object at
// static init time; it also seems to cause problems when the
// Panda shared library is unloaded at application exit time.
_attribs = new Attribs;
}
_saved_entry = _attribs->end();
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::Copy Constructor
// Access: Private
// Description: RenderAttribs are not meant to be copied.
////////////////////////////////////////////////////////////////////
RenderAttrib::
RenderAttrib(const RenderAttrib &) {
nassertv(false);
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::Copy Assignment Operator
// Access: Private
// Description: RenderAttribs are not meant to be copied.
////////////////////////////////////////////////////////////////////
void RenderAttrib::
operator = (const RenderAttrib &) {
nassertv(false);
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::Destructor
// Access: Public, Virtual
// Description: The destructor is responsible for removing the
// RenderAttrib from the global set if it is there.
////////////////////////////////////////////////////////////////////
RenderAttrib::
~RenderAttrib() {
if (_saved_entry != _attribs->end()) {
// We cannot make this assertion, because the RenderAttrib has
// already partially destructed--this means we cannot look up the
// object in the map. In fact, the map is temporarily invalid
// until we finish destructing, since we screwed up the ordering
// when we changed the return value of get_type().
// nassertv(_attribs->find(this) == _saved_entry);
// Note: this isn't thread-safe, because once the derived class
// destructor exits and before this destructor completes, the map
// is invalid, and other threads may inadvertently attempt to read
// the invalid map. To make it thread-safe, we need to move this
// functionality to a separate method, that is to be called from
// *each* derived class's destructor (and then we can put the
// above assert back in).
_attribs->erase(_saved_entry);
_saved_entry = _attribs->end();
}
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::issue
// Access: Public, Virtual
// Description: Calls the appropriate method on the indicated GSG
// to issue the graphics commands appropriate to the
// given attribute. This is normally called
// (indirectly) only from
// GraphicsStateGuardian::set_state() or modify_state().
////////////////////////////////////////////////////////////////////
void RenderAttrib::
issue(GraphicsStateGuardianBase *) const {
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::output
// Access: Published, Virtual
// Description:
////////////////////////////////////////////////////////////////////
void RenderAttrib::
output(ostream &out) const {
out << get_type();
}
void RenderAttrib::
output_comparefunc(ostream &out,PandaCompareFunc fn) const {
static char *FuncStrs[M_always+1] = {"none","never","less","equal", "less or equal","greater","not equal","greater or equal","always"};
out << FuncStrs[fn];
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::write
// Access: Published, Virtual
// Description:
////////////////////////////////////////////////////////////////////
void RenderAttrib::
write(ostream &out, int indent_level) const {
indent(out, indent_level) << *this << "\n";
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::return_new
// Access: Protected, Static
// Description: This function is used by derived RenderAttrib types
// to share a common RenderAttrib pointer for all
// equivalent RenderAttrib objects.
//
// The make() function of the derived type should create
// a new RenderAttrib and pass it through return_new(),
// which will either save the pointer and return it
// unchanged (if this is the first similar such object)
// or delete it and return an equivalent pointer (if
// there was already a similar object saved).
////////////////////////////////////////////////////////////////////
CPT(RenderAttrib) RenderAttrib::
return_new(RenderAttrib *attrib) {
nassertr(attrib != (RenderAttrib *)NULL, attrib);
// This should be a newly allocated pointer, not one that was used
// for anything else.
nassertr(attrib->_saved_entry == _attribs->end(), attrib);
// Save the attrib in a local PointerTo so that it will be freed at
// the end of this function if no one else uses it.
CPT(RenderAttrib) pt_attrib = attrib;
pair<Attribs::iterator, bool> result = _attribs->insert(attrib);
if (result.second) {
// The attribute was inserted; save the iterator and return the
// input attribute.
attrib->_saved_entry = result.first;
return pt_attrib;
}
// The attribute was not inserted; there must be an equivalent one
// already in the set. Return that one.
return *(result.first);
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::compare_to_impl
// Access: Protected, Virtual
// Description: Intended to be overridden by derived RenderAttrib
// types to return a unique number indicating whether
// this RenderAttrib is equivalent to the other one.
//
// This should return 0 if the two RenderAttrib objects
// are equivalent, a number less than zero if this one
// should be sorted before the other one, and a number
// greater than zero otherwise.
//
// This will only be called with two RenderAttrib
// objects whose get_type() functions return the same.
////////////////////////////////////////////////////////////////////
int RenderAttrib::
compare_to_impl(const RenderAttrib *other) const {
return 0;
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::compose_impl
// Access: Protected, Virtual
// Description: Intended to be overridden by derived RenderAttrib
// types to specify how two consecutive RenderAttrib
// objects of the same type interact.
//
// This should return the result of applying the other
// RenderAttrib to a node in the scene graph below this
// RenderAttrib, which was already applied. In most
// cases, the result is the same as the other
// RenderAttrib (that is, a subsequent RenderAttrib
// completely replaces the preceding one). On the other
// hand, some kinds of RenderAttrib (for instance,
// ColorTransformAttrib) might combine in meaningful
// ways.
////////////////////////////////////////////////////////////////////
CPT(RenderAttrib) RenderAttrib::
compose_impl(const RenderAttrib *other) const {
return other;
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::invert_compose_impl
// Access: Protected, Virtual
// Description: Intended to be overridden by derived RenderAttrib
// types to specify how two consecutive RenderAttrib
// objects of the same type interact.
//
// See invert_compose() and compose_impl().
////////////////////////////////////////////////////////////////////
CPT(RenderAttrib) RenderAttrib::
invert_compose_impl(const RenderAttrib *other) const {
return other;
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::make_default_impl
// Access: Protected, Virtual
// Description: Intended to be overridden by derived RenderAttrib
// types to specify what the default property for a
// RenderAttrib of this type should be.
//
// This should return a newly-allocated RenderAttrib of
// the same type that corresponds to whatever the
// standard default for this kind of RenderAttrib is.
////////////////////////////////////////////////////////////////////
RenderAttrib *RenderAttrib::
make_default_impl() const {
return (RenderAttrib *)NULL;
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::write_datagram
// Access: Public, Virtual
// Description: Writes the contents of this object to the datagram
// for shipping out to a Bam file.
////////////////////////////////////////////////////////////////////
void RenderAttrib::
write_datagram(BamWriter *manager, Datagram &dg) {
TypedWritable::write_datagram(manager, dg);
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::change_this
// Access: Public, Static
// Description: Called immediately after complete_pointers(), this
// gives the object a chance to adjust its own pointer
// if desired. Most objects don't change pointers after
// completion, but some need to.
//
// Once this function has been called, the old pointer
// will no longer be accessed.
////////////////////////////////////////////////////////////////////
TypedWritable *RenderAttrib::
change_this(TypedWritable *old_ptr, BamReader *manager) {
// First, uniquify the pointer.
RenderAttrib *attrib = DCAST(RenderAttrib, old_ptr);
CPT(RenderAttrib) pointer = return_new(attrib);
// But now we have a problem, since we have to hold the reference
// count and there's no way to return a TypedWritable while still
// holding the reference count! We work around this by explicitly
// upping the count, and also setting a finalize() callback to down
// it later.
if (pointer == attrib) {
pointer->ref();
manager->register_finalize(attrib);
}
// We have to cast the pointer back to non-const, because the bam
// reader expects that.
return (RenderAttrib *)pointer.p();
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::finalize
// Access: Public, Virtual
// Description: Method to ensure that any necessary clean up tasks
// that have to be performed by this object are performed
////////////////////////////////////////////////////////////////////
void RenderAttrib::
finalize() {
// Unref the pointer that we explicitly reffed in make_from_bam().
unref();
// We should never get back to zero after unreffing our own count,
// because we expect to have been stored in a pointer somewhere. If
// we do get to zero, it's a memory leak; the way to avoid this is
// to call unref_delete() above instead of unref(), but this is
// dangerous to do from within a virtual function.
nassertv(get_ref_count() != 0);
}
////////////////////////////////////////////////////////////////////
// Function: RenderAttrib::fillin
// Access: Protected
// Description: This internal function is called by make_from_bam to
// read in all of the relevant data from the BamFile for
// the new RenderAttrib.
////////////////////////////////////////////////////////////////////
void RenderAttrib::
fillin(DatagramIterator &scan, BamReader *manager) {
TypedWritable::fillin(scan, manager);
manager->register_change_this(change_this, this);
}