Panda3D

lwoPolygons.cxx
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1 /**
2 * PANDA 3D SOFTWARE
3 * Copyright (c) Carnegie Mellon University. All rights reserved.
4 *
5 * All use of this software is subject to the terms of the revised BSD
6 * license. You should have received a copy of this license along
7 * with this source code in a file named "LICENSE."
8 *
9 * @file lwoPolygons.cxx
10 * @author drose
11 * @date 2001-04-24
12 */
13
14 #include "lwoPolygons.h"
15 #include "lwoInputFile.h"
16
17 #include "dcast.h"
18 #include "indent.h"
19
20 TypeHandle LwoPolygons::_type_handle;
21
22 /**
23 * Returns the number of polygons of this group.
24 */
25 int LwoPolygons::
26 get_num_polygons() const {
27 return _polygons.size();
28 }
29
30 /**
31 * Returns the nth polygon of this group.
32 */
33 LwoPolygons::Polygon *LwoPolygons::
34 get_polygon(int n) const {
35 nassertr(n >= 0 && n < (int)_polygons.size(), nullptr);
36 return _polygons[n];
37 }
38
39 /**
40 * Reads the data of the chunk in from the given input file, if possible. The
41 * ID and length of the chunk have already been read. stop_at is the byte
42 * position of the file to stop at (based on the current position at
43 * in->get_bytes_read()). Returns true on success, false otherwise.
44 */
45 bool LwoPolygons::
46 read_iff(IffInputFile *in, size_t stop_at) {
47 LwoInputFile *lin = DCAST(LwoInputFile, in);
48
49 if (lin->get_lwo_version() >= 6.0) {
50 // 6.x style syntax: POLS { type[ID4], ( numvert+flags[U2], vert[VX] #
51 // numvert )* }
52
53 _polygon_type = lin->get_id();
54
55 while (lin->get_bytes_read() < stop_at && !lin->is_eof()) {
56 int nf = lin->get_be_uint16();
57 int num_vertices = nf & PF_numverts_mask;
58
59 PT(Polygon) poly = new Polygon;
60 poly->_flags = nf & ~PF_numverts_mask;
61 poly->_surface_index = -1;
62
63 for (int i = 0; i < num_vertices; i++) {
64 int vindex = lin->get_vx();
65 poly->_vertices.push_back(vindex);
66 }
67
68 _polygons.push_back(poly);
69 }
70
71 } else {
72 // 5.x style syntax: POLS { ( numvert[U2], vert[VX] # numvert,
73 // +-(surf+1)[I2], numdetail[U2]? )* }
74 _polygon_type = IffId("FACE");
75
76 int num_decals = 0;
77 while (lin->get_bytes_read() < stop_at && !lin->is_eof()) {
78 int num_vertices = lin->get_be_uint16();
79
80 PT(Polygon) poly = new Polygon;
81 poly->_flags = 0;
82
83 for (int i = 0; i < num_vertices; i++) {
84 int vindex = lin->get_vx();
85 poly->_vertices.push_back(vindex);
86 }
87
88 int surface = lin->get_be_int16();
89
90 if (num_decals > 0) {
91 // This is a decal polygon of a previous polygon.
92 num_decals--;
93 poly->_flags |= PF_decal;
94
95 } else {
96 if (surface < 0) {
97 num_decals = lin->get_be_int16();
98 surface = -surface;
99 }
100 }
101
102 // The surface index is stored +1 to allow signedness to be examined.
103 poly->_surface_index = surface - 1;
104
105 _polygons.push_back(poly);
106 }
107 }
108
109 return true;
110 }
111
112 /**
113 *
114 */
115 void LwoPolygons::
116 write(std::ostream &out, int indent_level) const {
117 indent(out, indent_level)
118 << get_id() << " { polygon_type = " << _polygon_type
119 << ", " << _polygons.size() << " polygons }\n";
120 }
IffChunk::get_id
IffId get_id() const
Returns the ID associated with this chunk.
Definition: iffChunk.I:25
IffId
A four-byte chunk ID appearing in an "IFF" file.
Definition: iffId.h:26
IffInputFile
A wrapper around an istream used for reading an IFF file.
Definition: iffInputFile.h:30
IffInputFile::get_be_uint16
uint16_t get_be_uint16()
Extracts an unsigned 16-bit big-endian integer.
Definition: iffInputFile.cxx:139
IffInputFile::get_id
IffId get_id()
Extracts a 4-character IFF ID.
Definition: iffInputFile.cxx:196
IffInputFile::get_bytes_read
size_t get_bytes_read() const
Returns the number of bytes read so far from the input file.
Definition: iffInputFile.I:44
IffInputFile::get_be_int16
int16_t get_be_int16()
Extracts a signed 16-bit big-endian integer.
Definition: iffInputFile.cxx:113
IffInputFile::is_eof
bool is_eof() const
Returns true if the last read operation failed because of reaching EOF, false otherwise.
Definition: iffInputFile.I:36
LwoInputFile
A specialization of IffInputFile to handle reading a Lightwave Object file.
Definition: lwoInputFile.h:26
LwoInputFile::get_lwo_version
double get_lwo_version() const
Returns the version of the Lightwave file being read.
Definition: lwoInputFile.I:19
LwoInputFile::get_vx
int get_vx()
Reads a Lightwave variable-length index.
Definition: lwoInputFile.cxx:50
LwoPolygons::Polygon
Definition: lwoPolygons.h:41
LwoPolygons::get_polygon
Polygon * get_polygon(int n) const
Returns the nth polygon of this group.
Definition: lwoPolygons.cxx:34
LwoPolygons::get_num_polygons
int get_num_polygons() const
Returns the number of polygons of this group.
Definition: lwoPolygons.cxx:26
LwoPolygons::read_iff
virtual bool read_iff(IffInputFile *in, size_t stop_at)
Reads the data of the chunk in from the given input file, if possible.
Definition: lwoPolygons.cxx:46
TypeHandle
TypeHandle is the identifier used to differentiate C++ class types.
Definition: typeHandle.h:81
dcast.h
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
indent
std::ostream & indent(std::ostream &out, int indent_level)
A handy function for doing text formatting.
Definition: indent.cxx:20
indent.h
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
lwoInputFile.h
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
lwoPolygons.h
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.