open_toontown_panda3d/panda/src/egg/eggTriangleFan.cxx

134 lines
4.6 KiB
C++

// Filename: eggTriangleFan.cxx
// Created by: drose (23Mar05)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) 2001 - 2004, 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://etc.cmu.edu/panda3d/docs/license/ .
//
// To contact the maintainers of this program write to
// panda3d-general@lists.sourceforge.net .
//
////////////////////////////////////////////////////////////////////
#include "eggTriangleFan.h"
#include "eggGroupNode.h"
#include "eggPolygon.h"
#include "indent.h"
TypeHandle EggTriangleFan::_type_handle;
////////////////////////////////////////////////////////////////////
// Function: EggTriangleFan::Destructor
// Access: Published, Virtual
// Description:
////////////////////////////////////////////////////////////////////
EggTriangleFan::
~EggTriangleFan() {
clear();
}
////////////////////////////////////////////////////////////////////
// Function: EggTriangleFan::write
// Access: Published, Virtual
// Description: Writes the triangle fan to the indicated output
// stream in Egg format.
////////////////////////////////////////////////////////////////////
void EggTriangleFan::
write(ostream &out, int indent_level) const {
write_header(out, indent_level, "<TriangleFan>");
write_body(out, indent_level+2);
indent(out, indent_level) << "}\n";
}
////////////////////////////////////////////////////////////////////
// Function: EggTriangleFan::apply_first_attribute
// Access: Published, Virtual
// Description: Sets the first vertex of the triangle (or each
// component) to the primitive normal and/or color, if
// the primitive is flat-shaded. This reflects the
// DirectX convention of storing flat-shaded properties
// on the first vertex, although it is not usually a
// convention in Egg.
//
// This may introduce redundant vertices to the vertex
// pool.
////////////////////////////////////////////////////////////////////
void EggTriangleFan::
apply_first_attribute() {
// In the case of a triangle fan, the first vertex of the fan is the
// common vertex, so we consider the second vertex to be the key
// vertex of the first triangle, and move from there.
for (int i = 0; i < get_num_components(); i++) {
EggAttributes *component = get_component(i);
do_apply_flat_attribute(i + 1, component);
}
}
////////////////////////////////////////////////////////////////////
// Function: EggTriangleFan::get_num_lead_vertices
// Access: Protected, Virtual
// Description: Returns the number of initial vertices that are not
// used in defining any component; the first component
// is defined by the (n + 1)th vertex, and then a new
// component at each vertex thereafter.
////////////////////////////////////////////////////////////////////
int EggTriangleFan::
get_num_lead_vertices() const {
return 2;
}
////////////////////////////////////////////////////////////////////
// Function: EggTriangleFan::triangulate_poly
// Access: Protected, Virtual
// Description: Fills the container up with EggPolygons that
// represent the component triangles of this triangle
// fan.
//
// It is assumed that the EggTriangleFan is not
// already a child of any other group when this function
// is called.
//
// Returns true if the triangulation is successful, or
// false if there was some error (in which case the
// container may contain some partial triangulation).
////////////////////////////////////////////////////////////////////
bool EggTriangleFan::
do_triangulate(EggGroupNode *container) const {
if (size() < 3) {
return false;
}
const_iterator vi = begin();
EggVertex *v0 = (*vi);
++vi;
EggVertex *v1 = (*vi);
++vi;
for (int i = 0; i < (int)size() - 2; i++) {
PT(EggPolygon) poly = new EggPolygon;
poly->copy_attributes(*this);
const EggAttributes *attrib = get_component(i);
if (attrib->has_color()) {
poly->set_color(attrib->get_color());
}
if (attrib->has_normal()) {
poly->set_normal(attrib->get_normal());
}
poly->add_vertex(v0);
poly->add_vertex(v1);
poly->add_vertex(*vi);
v1 = *vi;
container->add_child(poly);
++vi;
}
return true;
}