open_toontown_panda3d/panda/src/pgraph/depthOffsetAttrib.cxx

204 lines
6.4 KiB
C++

/**
* PANDA 3D SOFTWARE
* Copyright (c) Carnegie Mellon University. All rights reserved.
*
* All use of this software is subject to the terms of the revised BSD
* license. You should have received a copy of this license along
* with this source code in a file named "LICENSE."
*
* @file depthOffsetAttrib.cxx
* @author drose
* @date 2002-03-14
*/
#include "depthOffsetAttrib.h"
#include "graphicsStateGuardianBase.h"
#include "dcast.h"
#include "bamReader.h"
#include "bamWriter.h"
#include "datagram.h"
#include "datagramIterator.h"
TypeHandle DepthOffsetAttrib::_type_handle;
int DepthOffsetAttrib::_attrib_slot;
/**
* Constructs a new DepthOffsetAttrib object that indicates the relative
* amount of bias to write to the depth buffer for subsequent geometry.
*/
CPT(RenderAttrib) DepthOffsetAttrib::
make(int offset) {
DepthOffsetAttrib *attrib = new DepthOffsetAttrib(offset, 0.0f, 1.0f);
return return_new(attrib);
}
/**
* Constructs a new DepthOffsetAttrib object that indicates the bias, and also
* specifies a minimum and maximum (or, more precisely, nearest and farthest)
* values to write to the depth buffer, in the range 0 .. 1. This range is 0,
* 1 by default; setting it to some other range can be used to create
* additional depth buffer effects.
*/
CPT(RenderAttrib) DepthOffsetAttrib::
make(int offset, PN_stdfloat min_value, PN_stdfloat max_value) {
nassertr(min_value >= 0.0f && min_value <= 1.0f, nullptr);
nassertr(max_value >= 0.0f && max_value <= 1.0f, nullptr);
DepthOffsetAttrib *attrib = new DepthOffsetAttrib(offset, min_value, max_value);
return return_new(attrib);
}
/**
* Returns a RenderAttrib that corresponds to whatever the standard default
* properties for render attributes of this type ought to be.
*/
CPT(RenderAttrib) DepthOffsetAttrib::
make_default() {
return return_new(new DepthOffsetAttrib(0, 0.0f, 1.0f));
}
/**
*
*/
void DepthOffsetAttrib::
output(std::ostream &out) const {
out << get_type() << ":(" << get_offset() << ", " << get_min_value()
<< ", " << get_max_value() << ")";
}
/**
* Intended to be overridden by derived DepthOffsetAttrib types to return a
* unique number indicating whether this DepthOffsetAttrib is equivalent to
* the other one.
*
* This should return 0 if the two DepthOffsetAttrib 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 DepthOffsetAttrib objects whose
* get_type() functions return the same.
*/
int DepthOffsetAttrib::
compare_to_impl(const RenderAttrib *other) const {
const DepthOffsetAttrib *ta = (const DepthOffsetAttrib *)other;
if (_offset != ta->_offset) {
return _offset - ta->_offset;
}
if (_min_value != ta->_min_value) {
return _min_value < ta->_min_value ? -1 : 1;
}
if (_max_value != ta->_max_value) {
return _max_value < ta->_max_value ? -1 : 1;
}
return 0;
}
/**
* Intended to be overridden by derived RenderAttrib types to return a unique
* hash for these particular properties. RenderAttribs that compare the same
* with compare_to_impl(), above, should return the same hash; RenderAttribs
* that compare differently should return a different hash.
*/
size_t DepthOffsetAttrib::
get_hash_impl() const {
size_t hash = 0;
hash = int_hash::add_hash(hash, _offset);
hash = float_hash().add_hash(hash, _min_value);
hash = float_hash().add_hash(hash, _max_value);
return hash;
}
/**
* 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) DepthOffsetAttrib::
compose_impl(const RenderAttrib *other) const {
const DepthOffsetAttrib *ta = (const DepthOffsetAttrib *)other;
int new_offset = ta->_offset + _offset;
DepthOffsetAttrib *attrib = new DepthOffsetAttrib(new_offset, ta->_min_value, ta->_max_value);
return return_new(attrib);
}
/**
* 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) DepthOffsetAttrib::
invert_compose_impl(const RenderAttrib *other) const {
const DepthOffsetAttrib *ta = (const DepthOffsetAttrib *)other;
int new_offset = ta->_offset - _offset;
DepthOffsetAttrib *attrib = new DepthOffsetAttrib(new_offset, ta->_min_value, ta->_max_value);
return return_new(attrib);
}
/**
* Tells the BamReader how to create objects of type DepthOffsetAttrib.
*/
void DepthOffsetAttrib::
register_with_read_factory() {
BamReader::get_factory()->register_factory(get_class_type(), make_from_bam);
}
/**
* Writes the contents of this object to the datagram for shipping out to a
* Bam file.
*/
void DepthOffsetAttrib::
write_datagram(BamWriter *manager, Datagram &dg) {
RenderAttrib::write_datagram(manager, dg);
dg.add_int32(_offset);
if (manager->get_file_minor_ver() >= 31) {
dg.add_stdfloat(_min_value);
dg.add_stdfloat(_max_value);
}
}
/**
* This function is called by the BamReader's factory when a new object of
* type DepthOffsetAttrib is encountered in the Bam file. It should create
* the DepthOffsetAttrib and extract its information from the file.
*/
TypedWritable *DepthOffsetAttrib::
make_from_bam(const FactoryParams &params) {
DepthOffsetAttrib *attrib = new DepthOffsetAttrib(0, 0.0f, 1.0f);
DatagramIterator scan;
BamReader *manager;
parse_params(params, scan, manager);
attrib->fillin(scan, manager);
return attrib;
}
/**
* This internal function is called by make_from_bam to read in all of the
* relevant data from the BamFile for the new DepthOffsetAttrib.
*/
void DepthOffsetAttrib::
fillin(DatagramIterator &scan, BamReader *manager) {
RenderAttrib::fillin(scan, manager);
_offset = scan.get_int32();
_min_value = 0.0f;
_max_value = 1.0f;
if (manager->get_file_minor_ver() >= 31) {
_min_value = scan.get_stdfloat();
_max_value = scan.get_stdfloat();
}
}