Panda3D
spotlight.cxx
Go to the documentation of this file.
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 spotlight.cxx
10  * @author mike
11  * @date 1997-01-09
12  */
13 
14 #include "spotlight.h"
16 #include "bamWriter.h"
17 #include "bamReader.h"
18 #include "datagram.h"
19 #include "datagramIterator.h"
20 #include "colorAttrib.h"
21 #include "texture.h"
22 #include "config_pgraph.h"
23 #include "pnmImage.h"
24 
25 TypeHandle Spotlight::_type_handle;
26 
27 /**
28  *
29  */
30 CycleData *Spotlight::CData::
31 make_copy() const {
32  return new CData(*this);
33 }
34 
35 /**
36  * Writes the contents of this object to the datagram for shipping out to a
37  * Bam file.
38  */
39 void Spotlight::CData::
40 write_datagram(BamWriter *manager, Datagram &dg) const {
41  dg.add_stdfloat(_exponent);
42  _specular_color.write_datagram(dg);
43  _attenuation.write_datagram(dg);
44  if (manager->get_file_minor_ver() >= 41) {
45  dg.add_stdfloat(_max_distance);
46  }
47 }
48 
49 /**
50  * This internal function is called by make_from_bam to read in all of the
51  * relevant data from the BamFile for the new Light.
52  */
53 void Spotlight::CData::
54 fillin(DatagramIterator &scan, BamReader *manager) {
55  _exponent = scan.get_stdfloat();
56  _specular_color.read_datagram(scan);
57  _attenuation.read_datagram(scan);
58  if (manager->get_file_minor_ver() >= 41) {
59  _max_distance = scan.get_stdfloat();
60  }
61 }
62 
63 /**
64  *
65  */
66 Spotlight::
67 Spotlight(const std::string &name) :
68  LightLensNode(name) {
69  _lenses[0]._lens->set_interocular_distance(0);
70 }
71 
72 /**
73  * Do not call the copy constructor directly; instead, use make_copy() or
74  * copy_subgraph() to make a copy of a node.
75  */
76 Spotlight::
77 Spotlight(const Spotlight &copy) :
78  LightLensNode(copy),
79  _cycler(copy._cycler)
80 {
81 }
82 
83 /**
84  * Returns a newly-allocated PandaNode that is a shallow copy of this one. It
85  * will be a different pointer, but its internal data may or may not be shared
86  * with that of the original PandaNode. No children will be copied.
87  */
89 make_copy() const {
90  return new Spotlight(*this);
91 }
92 
93 /**
94  * Transforms the contents of this PandaNode by the indicated matrix, if it
95  * means anything to do so. For most kinds of PandaNodes, this does nothing.
96  */
98 xform(const LMatrix4 &mat) {
100  mark_viz_stale();
101 }
102 
103 /**
104  *
105  */
106 void Spotlight::
107 write(std::ostream &out, int indent_level) const {
108  indent(out, indent_level) << *this << ":\n";
109  indent(out, indent_level + 2)
110  << "color " << get_color() << "\n";
111  if (_has_specular_color) {
112  indent(out, indent_level + 2)
113  << "specular color " << get_specular_color() << "\n";
114  }
115  indent(out, indent_level + 2)
116  << "attenuation " << get_attenuation() << "\n";
117  indent(out, indent_level + 2)
118  << "exponent " << get_exponent() << "\n";
119 
120  if (!cinf(get_max_distance())) {
121  indent(out, indent_level + 2)
122  << "max distance " << get_max_distance() << "\n";
123  }
124 
125  Lens *lens = get_lens();
126  if (lens != nullptr) {
127  lens->write(out, indent_level + 2);
128  }
129 }
130 
131 /**
132  * Computes the vector from a particular vertex to this light. The exact
133  * vector depends on the type of light (e.g. point lights return a different
134  * result than directional lights).
135  *
136  * The input parameters are the vertex position in question, expressed in
137  * object space, and the matrix which converts from light space to object
138  * space. The result is expressed in object space.
139  *
140  * The return value is true if the result is successful, or false if it cannot
141  * be computed (e.g. for an ambient light).
142  */
144 get_vector_to_light(LVector3 &result, const LPoint3 &from_object_point,
145  const LMatrix4 &to_object_space) {
146  return false;
147 }
148 
149 /**
150  * Returns a newly-generated Texture that renders a circular spot image as
151  * might be cast from the spotlight. This may be projected onto target
152  * geometry (for instance, via NodePath::project_texture()) instead of
153  * actually enabling the light itself, as a cheesy way to make a high-
154  * resolution spot appear on the geometry.
155  *
156  * pixel_width specifies the height and width of the new texture in pixels,
157  * full_radius is a value in the range 0..1 that indicates the relative size
158  * of the fully bright center spot, and fg and bg are the colors of the
159  * interior and exterior of the spot, respectively.
160  */
161 PT(Texture) Spotlight::
162 make_spot(int pixel_width, PN_stdfloat full_radius, LColor &fg, LColor &bg) {
163  int num_channels;
164  if (fg[0] == fg[1] && fg[1] == fg[2] &&
165  bg[0] == bg[1] && bg[1] == bg[2]) {
166  // grayscale
167  num_channels = 1;
168  } else {
169  // color
170  num_channels = 3;
171  }
172  if (fg[3] != 1.0f || bg[3] != 1.0f) {
173  // with alpha.
174  ++num_channels;
175  }
176  PNMImage image(pixel_width, pixel_width, num_channels);
177  image.render_spot(LCAST(float, fg), LCAST(float, bg), full_radius, 1.0);
178 
179  PT(Texture) tex = new Texture("spot");
180  tex->load(image);
181  tex->set_border_color(bg);
182  tex->set_wrap_u(SamplerState::WM_border_color);
183  tex->set_wrap_v(SamplerState::WM_border_color);
184 
185  tex->set_minfilter(SamplerState::FT_linear);
186  tex->set_magfilter(SamplerState::FT_linear);
187 
188  return tex;
189 }
190 
191 /**
192  * Returns the relative priority associated with all lights of this class.
193  * This priority is used to order lights whose instance priority
194  * (get_priority()) is the same--the idea is that other things being equal,
195  * AmbientLights (for instance) are less important than DirectionalLights.
196  */
198 get_class_priority() const {
199  return (int)CP_spot_priority;
200 }
201 
202 /**
203  *
204  */
205 void Spotlight::
206 bind(GraphicsStateGuardianBase *gsg, const NodePath &light, int light_id) {
207  gsg->bind_light(this, light, light_id);
208 }
209 
210 /**
211  * Fills the indicated GeomNode up with Geoms suitable for rendering this
212  * light.
213  */
214 void Spotlight::
215 fill_viz_geom(GeomNode *viz_geom) {
216  Lens *lens = get_lens();
217  if (lens == nullptr) {
218  return;
219  }
220 
221  PT(Geom) geom = lens->make_geometry();
222  if (geom == nullptr) {
223  return;
224  }
225 
226  viz_geom->add_geom(geom, get_viz_state());
227 }
228 
229 /**
230  * Returns a RenderState for rendering the spotlight visualization.
231  */
232 CPT(RenderState) Spotlight::
233 get_viz_state() {
234  return RenderState::make
235  (ColorAttrib::make_flat(get_color()));
236 }
237 
238 /**
239  * Tells the BamReader how to create objects of type Spotlight.
240  */
243  BamReader::get_factory()->register_factory(get_class_type(), make_from_bam);
244 }
245 
246 /**
247  * Writes the contents of this object to the datagram for shipping out to a
248  * Bam file.
249  */
251 write_datagram(BamWriter *manager, Datagram &dg) {
252  LightLensNode::write_datagram(manager, dg);
253  if (manager->get_file_minor_ver() >= 39) {
254  dg.add_bool(_has_specular_color);
255  }
256  manager->write_cdata(dg, _cycler);
257 }
258 
259 /**
260  * This function is called by the BamReader's factory when a new object of
261  * type Spotlight is encountered in the Bam file. It should create the
262  * Spotlight and extract its information from the file.
263  */
264 TypedWritable *Spotlight::
265 make_from_bam(const FactoryParams &params) {
266  Spotlight *node = new Spotlight("");
267  DatagramIterator scan;
268  BamReader *manager;
269 
270  parse_params(params, scan, manager);
271  node->fillin(scan, manager);
272 
273  return node;
274 }
275 
276 /**
277  * This internal function is called by make_from_bam to read in all of the
278  * relevant data from the BamFile for the new Spotlight.
279  */
280 void Spotlight::
281 fillin(DatagramIterator &scan, BamReader *manager) {
282  LightLensNode::fillin(scan, manager);
283 
284  if (manager->get_file_minor_ver() >= 39) {
285  _has_specular_color = scan.get_bool();
286  } else {
287  _has_specular_color = true;
288  }
289 
290  manager->read_cdata(scan, _cycler);
291 }
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
void parse_params(const FactoryParams &params, DatagramIterator &scan, BamReader *&manager)
Takes in a FactoryParams, passed from a WritableFactory into any TypedWritable's make function,...
Definition: bamReader.I:275
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
This is the fundamental interface for extracting binary objects from a Bam file, as generated by a Ba...
Definition: bamReader.h:110
int get_file_minor_ver() const
Returns the minor version number of the Bam file currently being read.
Definition: bamReader.I:83
void read_cdata(DatagramIterator &scan, PipelineCyclerBase &cycler)
Reads in the indicated CycleData object.
Definition: bamReader.cxx:695
static WritableFactory * get_factory()
Returns the global WritableFactory for generating TypedWritable objects.
Definition: bamReader.I:177
This is the fundamental interface for writing binary objects to a Bam file, to be extracted later by ...
Definition: bamWriter.h:63
void write_cdata(Datagram &packet, const PipelineCyclerBase &cycler)
Writes out the indicated CycleData object.
Definition: bamWriter.cxx:425
int get_file_minor_ver() const
Returns the minor version number of the Bam file currently being written.
Definition: bamWriter.I:59
A single page of data maintained by a PipelineCycler.
Definition: cycleData.h:50
A class to retrieve the individual data elements previously stored in a Datagram.
PN_stdfloat get_stdfloat()
Extracts either a 32-bit or a 64-bit floating-point number, according to Datagram::set_stdfloat_doubl...
bool get_bool()
Extracts a boolean value.
An ordered list of data elements, formatted in memory for transmission over a socket or writing to a ...
Definition: datagram.h:38
void add_stdfloat(PN_stdfloat value)
Adds either a 32-bit or a 64-bit floating-point number, according to set_stdfloat_double().
Definition: datagram.I:133
void add_bool(bool value)
Adds a boolean value to the datagram.
Definition: datagram.I:34
An instance of this class is passed to the Factory when requesting it to do its business and construc...
Definition: factoryParams.h:36
void register_factory(TypeHandle handle, CreateFunc *func, void *user_data=nullptr)
Registers a new kind of thing the Factory will be able to create.
Definition: factory.I:73
A node that holds Geom objects, renderable pieces of geometry.
Definition: geomNode.h:34
void add_geom(Geom *geom, const RenderState *state=RenderState::make_empty())
Adds a new Geom to the node.
Definition: geomNode.cxx:586
A container for geometry primitives.
Definition: geom.h:54
This is a base class for the GraphicsStateGuardian class, which is itself a base class for the variou...
virtual void xform(const LMatrix4 &mat)
Transforms the contents of this PandaNode by the indicated matrix, if it means anything to do so.
Definition: lensNode.cxx:53
Lens * get_lens(int index=0) const
Returns a pointer to the particular Lens associated with this LensNode, or NULL if there is not yet a...
Definition: lensNode.I:47
A base class for any number of different kinds of lenses, linear and otherwise.
Definition: lens.h:41
A derivative of Light and of Camera.
Definition: lightLensNode.h:33
virtual void write_datagram(BamWriter *manager, Datagram &dg)
Writes the contents of this object to the datagram for shipping out to a Bam file.
get_color
Returns the basic color of the light.
Definition: light.h:49
NodePath is the fundamental system for disambiguating instances, and also provides a higher-level int...
Definition: nodePath.h:159
The name of this class derives from the fact that we originally implemented it as a layer on top of t...
Definition: pnmImage.h:58
void render_spot(const LColorf &fg, const LColorf &bg, float min_radius, float max_radius)
Renders a solid-color circle, with a fuzzy edge, into the center of the PNMImage.
Definition: pnmImage.cxx:1789
A basic node of the scene graph or data graph.
Definition: pandaNode.h:65
This represents a unique collection of RenderAttrib objects that correspond to a particular renderabl...
Definition: renderState.h:47
A light originating from a single point in space, and shining in a particular direction,...
Definition: spotlight.h:32
get_specular_color
Returns the color of specular highlights generated by the light.
Definition: spotlight.h:56
get_exponent
Returns the exponent that controls the amount of light falloff from the center of the spotlight.
Definition: spotlight.h:51
get_attenuation
Returns the terms of the attenuation equation for the light.
Definition: spotlight.h:60
static void register_with_read_factory()
Tells the BamReader how to create objects of type Spotlight.
Definition: spotlight.cxx:242
virtual int get_class_priority() const
Returns the relative priority associated with all lights of this class.
Definition: spotlight.cxx:198
virtual bool get_vector_to_light(LVector3 &result, const LPoint3 &from_object_point, const LMatrix4 &to_object_space)
Computes the vector from a particular vertex to this light.
Definition: spotlight.cxx:144
virtual void write_datagram(BamWriter *manager, Datagram &dg)
Writes the contents of this object to the datagram for shipping out to a Bam file.
Definition: spotlight.cxx:251
get_max_distance
Returns the maximum distance at which the light has any effect, as previously specified by set_max_di...
Definition: spotlight.h:64
virtual void xform(const LMatrix4 &mat)
Transforms the contents of this PandaNode by the indicated matrix, if it means anything to do so.
Definition: spotlight.cxx:98
virtual PandaNode * make_copy() const
Returns a newly-allocated PandaNode that is a shallow copy of this one.
Definition: spotlight.cxx:89
Represents a texture object, which is typically a single 2-d image but may also represent a 1-d or 3-...
Definition: texture.h:71
TypeHandle is the identifier used to differentiate C++ class types.
Definition: typeHandle.h:81
Base class for objects that can be written to and read from Bam files.
Definition: typedWritable.h:35
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
std::ostream & indent(std::ostream &out, int indent_level)
A handy function for doing text formatting.
Definition: indent.cxx:20
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
CPT(RenderState) Spotlight
Returns a RenderState for rendering the spotlight visualization.
Definition: spotlight.cxx:232
PT(Texture) Spotlight
Returns a newly-generated Texture that renders a circular spot image as might be cast from the spotli...
Definition: spotlight.cxx:161
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.