Point Cloud Library (PCL)  1.14.1-dev
world_model.hpp
1 /*
2  * Software License Agreement (BSD License)
3  *
4  * Point Cloud Library (PCL) - www.pointclouds.org
5  * Copyright (c) 2010-2011, Willow Garage, Inc.
6  *
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * * Redistributions of source code must retain the above copyright
14  * notice, this list of conditions and the following disclaimer.
15  * * Redistributions in binary form must reproduce the above
16  * copyright notice, this list of conditions and the following
17  * disclaimer in the documentation and/or other materials provided
18  * with the distribution.
19  * * Neither the name of Willow Garage, Inc. nor the names of its
20  * contributors may be used to endorse or promote products derived
21  * from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
26  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
27  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
29  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
30  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
31  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
33  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  *
36  * Author: Raphael Favier, Technical University Eindhoven, (r.mysurname <aT> tue.nl)
37  */
38 
39 #ifndef PCL_WORLD_MODEL_IMPL_HPP_
40 #define PCL_WORLD_MODEL_IMPL_HPP_
41 
42 #include <pcl/gpu/kinfu_large_scale/world_model.h>
43 #include <pcl/common/transforms.h> // for transformPointCloud
44 
45 template <typename PointT>
46 void
48 {
49  PCL_DEBUG("Adding new cloud. Current world contains %zu points.\n",
50  static_cast<std::size_t>(world_->size()));
51 
52  PCL_DEBUG("New slice contains %zu points.\n",
53  static_cast<std::size_t>(new_cloud->size()));
54 
55  *world_ += *new_cloud;
56 
57  PCL_DEBUG("World now contains %zu points.\n",
58  static_cast<std::size_t>(world_->size()));
59 }
60 
61 template <typename PointT>
62 void
63 pcl::kinfuLS::WorldModel<PointT>::getExistingData(const double previous_origin_x, const double previous_origin_y, const double previous_origin_z, const double offset_x, const double offset_y, const double offset_z, const double volume_x, const double volume_y, const double volume_z, pcl::PointCloud<PointT> &existing_slice)
64 {
65  double newOriginX = previous_origin_x + offset_x;
66  double newOriginY = previous_origin_y + offset_y;
67  double newOriginZ = previous_origin_z + offset_z;
68  double newLimitX = newOriginX + volume_x;
69  double newLimitY = newOriginY + volume_y;
70  double newLimitZ = newOriginZ + volume_z;
71 
72  // filter points in the space of the new cube
74  // condition
75  ConditionAndPtr range_condAND (new pcl::ConditionAnd<PointT> ());
76  range_condAND->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::GE, newOriginX)));
77  range_condAND->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::LT, newLimitX)));
78  range_condAND->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::GE, newOriginY)));
79  range_condAND->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::LT, newLimitY)));
80  range_condAND->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::GE, newOriginZ)));
81  range_condAND->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::LT, newLimitZ)));
82 
83  // build the filter
84  pcl::ConditionalRemoval<PointT> condremAND (true);
85  condremAND.setCondition (range_condAND);
86  condremAND.setInputCloud (world_);
87  condremAND.setKeepOrganized (false);
88 
89  // apply filter
90  condremAND.filter (*newCube);
91 
92  // filter points that belong to the new slice
93  ConditionOrPtr range_condOR (new pcl::ConditionOr<PointT> ());
94 
95  if(offset_x >= 0)
96  range_condOR->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::GE, previous_origin_x + volume_x - 1.0 )));
97  else
98  range_condOR->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::LT, previous_origin_x )));
99 
100  if(offset_y >= 0)
101  range_condOR->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::GE, previous_origin_y + volume_y - 1.0 )));
102  else
103  range_condOR->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::LT, previous_origin_y )));
104 
105  if(offset_z >= 0)
106  range_condOR->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::GE, previous_origin_z + volume_z - 1.0 )));
107  else
108  range_condOR->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::LT, previous_origin_z )));
109 
110  // build the filter
111  pcl::ConditionalRemoval<PointT> condrem (true);
112  condrem.setCondition (range_condOR);
113  condrem.setInputCloud (newCube);
114  condrem.setKeepOrganized (false);
115  // apply filter
116  condrem.filter (existing_slice);
117 
118  if(!existing_slice.empty ())
119  {
120  //transform the slice in new cube coordinates
121  Eigen::Affine3f transformation;
122  transformation.translation ()[0] = newOriginX;
123  transformation.translation ()[1] = newOriginY;
124  transformation.translation ()[2] = newOriginZ;
125 
126  transformation.linear ().setIdentity ();
127 
128  transformPointCloud (existing_slice, existing_slice, transformation.inverse ());
129 
130  }
131 }
132 
133 
134 template <typename PointT>
135 void
136 pcl::kinfuLS::WorldModel<PointT>::getWorldAsCubes (const double size, std::vector<typename WorldModel<PointT>::PointCloudPtr> &cubes, std::vector<Eigen::Vector3f, Eigen::aligned_allocator<Eigen::Vector3f> > &transforms, double overlap)
137 {
138 
139  if(world_->points.empty ())
140  {
141  PCL_INFO("The world is empty, returning nothing\n");
142  return;
143  }
144 
145  PCL_INFO("Getting world as cubes. World contains %zu points.\n",
146  static_cast<std::size_t>(world_->size()));
147 
148  // remove nans from world cloud
149  world_->is_dense = false;
150  pcl::Indices indices;
151  pcl::removeNaNFromPointCloud ( *world_, *world_, indices);
152 
153  PCL_INFO("World contains %zu points after nan removal.\n",
154  static_cast<std::size_t>(world_->size()));
155 
156  // check cube size value
157  double cubeSide = size;
158  if (cubeSide <= 0.0f)
159  {
160  PCL_ERROR ("Size of the cube must be positive and non null (%f given). Setting it to 3.0 meters.\n", cubeSide);
161  cubeSide = 512.0f;
162  }
163 
164  std::cout << "cube size is set to " << cubeSide << std::endl;
165 
166  // check overlap value
167  double step_increment = 1.0f - overlap;
168  if (overlap < 0.0)
169  {
170  PCL_ERROR ("Overlap ratio must be positive or null (%f given). Setting it to 0.0 procent.\n", overlap);
171  step_increment = 1.0f;
172  }
173  if (overlap > 1.0)
174  {
175  PCL_ERROR ("Overlap ratio must be less or equal to 1.0 (%f given). Setting it to 10 procent.\n", overlap);
176  step_increment = 0.1f;
177  }
178 
179 
180  // get world's bounding values on XYZ
181  PointT min, max;
182  pcl::getMinMax3D(*world_, min, max);
183 
184  PCL_INFO ("Bounding box for the world: \n\t [%f - %f] \n\t [%f - %f] \n\t [%f - %f] \n", min.x, max.x, min.y, max.y, min.z, max.z);
185 
186  PointT origin = min;
187 
188  // clear returned vectors
189  cubes.clear();
190  transforms.clear();
191 
192  // iterate with box filter
193  while (origin.x < max.x)
194  {
195  origin.y = min.y;
196  while (origin.y < max.y)
197  {
198  origin.z = min.z;
199  while (origin.z < max.z)
200  {
201  // extract cube here
202  PCL_INFO ("Extracting cube at: [%f, %f, %f].\n", origin.x, origin.y, origin.z);
203 
204  // pointcloud for current cube.
205  PointCloudPtr box (new pcl::PointCloud<PointT>);
206 
207 
208  // set conditional filter
209  ConditionAndPtr range_cond (new pcl::ConditionAnd<PointT> ());
210  range_cond->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::GE, origin.x)));
211  range_cond->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::LT, origin.x + cubeSide)));
212  range_cond->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::GE, origin.y)));
213  range_cond->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::LT, origin.y + cubeSide)));
214  range_cond->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::GE, origin.z)));
215  range_cond->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::LT, origin.z + cubeSide)));
216 
217  // build the filter
219  condrem.setCondition (range_cond);
220  condrem.setInputCloud (world_);
221  condrem.setKeepOrganized(false);
222  // apply filter
223  condrem.filter (*box);
224 
225  // also push transform along with points.
226  if(!box->points.empty ())
227  {
228  Eigen::Vector3f transform;
229  transform[0] = origin.x, transform[1] = origin.y, transform[2] = origin.z;
230  transforms.push_back(transform);
231  cubes.push_back(box);
232  }
233  else
234  {
235  PCL_INFO ("Extracted cube was empty, skipping this one.\n");
236  }
237  origin.z += cubeSide * step_increment;
238  }
239  origin.y += cubeSide * step_increment;
240  }
241  origin.x += cubeSide * step_increment;
242  }
243 
244 
245  /* for(int c = 0 ; c < cubes.size() ; ++c)
246  {
247  std::stringstream name;
248  name << "cloud" << c+1 << ".pcd";
249  pcl::io::savePCDFileASCII(name.str(), *(cubes[c]));
250 
251  }*/
252 
253  std::cout << "returning " << cubes.size() << " cubes" << std::endl;
254 }
255 
256 template <typename PointT>
257 inline void
258 pcl::kinfuLS::WorldModel<PointT>::setIndicesAsNans (PointCloudPtr cloud, IndicesConstPtr indices)
259 {
260  std::vector<pcl::PCLPointField> fields;
261  pcl::for_each_type<FieldList> (pcl::detail::FieldAdder<PointT> (fields));
262  float my_nan = std::numeric_limits<float>::quiet_NaN ();
263 
264  for (int rii = 0; rii < static_cast<int> (indices->size ()); ++rii) // rii = removed indices iterator
265  {
266  std::uint8_t* pt_data = reinterpret_cast<std::uint8_t*> (&(*cloud)[(*indices)[rii]]);
267  for (const auto &field : fields)
268  memcpy (pt_data + field.offset, &my_nan, sizeof (float));
269  }
270 }
271 
272 
273 template <typename PointT>
274 void
275 pcl::kinfuLS::WorldModel<PointT>::setSliceAsNans (const double origin_x, const double origin_y, const double origin_z, const double offset_x, const double offset_y, const double offset_z, const int size_x, const int size_y, const int size_z)
276 {
277  // PCL_DEBUG ("IN SETSLICE AS NANS\n");
278 
280 
281  // prepare filter limits on all dimensions
282  double previous_origin_x = origin_x;
283  double previous_limit_x = origin_x + size_x - 1;
284  double new_origin_x = origin_x + offset_x;
285  double new_limit_x = previous_limit_x + offset_x;
286 
287  double previous_origin_y = origin_y;
288  double previous_limit_y = origin_y + size_y - 1;
289  double new_origin_y = origin_y + offset_y;
290  double new_limit_y = previous_limit_y + offset_y;
291 
292  double previous_origin_z = origin_z;
293  double previous_limit_z = origin_z + size_z - 1;
294  double new_origin_z = origin_z + offset_z;
295  double new_limit_z = previous_limit_z + offset_z;
296 
297  // get points of slice on X (we actually set a negative filter and set the ouliers (so, our slice points) to nan)
298  double lower_limit_x, upper_limit_x;
299  if(offset_x >=0)
300  {
301  lower_limit_x = previous_origin_x;
302  upper_limit_x = new_origin_x;
303  }
304  else
305  {
306  lower_limit_x = new_limit_x;
307  upper_limit_x = previous_limit_x;
308  }
309 
310  // PCL_DEBUG ("Limit X: [%f - %f]\n", lower_limit_x, upper_limit_x);
311 
312  ConditionOrPtr range_cond_OR_x (new pcl::ConditionOr<PointT> ());
313  range_cond_OR_x->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::GE, upper_limit_x ))); // filtered dimension
314  range_cond_OR_x->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::LT, lower_limit_x ))); // filtered dimension
315 
316  range_cond_OR_x->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::GE, previous_limit_y)));
317  range_cond_OR_x->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::LT, previous_origin_y )));
318 
319  range_cond_OR_x->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::GE, previous_limit_z)));
320  range_cond_OR_x->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::LT, previous_origin_z )));
321 
322  pcl::ConditionalRemoval<PointT> condrem_x (true);
323  condrem_x.setCondition (range_cond_OR_x);
324  condrem_x.setInputCloud (world_);
325  condrem_x.setKeepOrganized (false);
326  // apply filter
327  condrem_x.filter (*slice);
328  IndicesConstPtr indices_x = condrem_x.getRemovedIndices ();
329 
330  //set outliers (so our slice points) to nan
331  setIndicesAsNans(world_, indices_x);
332 
333  // PCL_DEBUG("%d points set to nan on X\n", indices_x->size ());
334 
335  // get points of slice on Y (we actually set a negative filter and set the ouliers (so, our slice points) to nan)
336  double lower_limit_y, upper_limit_y;
337  if(offset_y >=0)
338  {
339  lower_limit_y = previous_origin_y;
340  upper_limit_y = new_origin_y;
341  }
342  else
343  {
344  lower_limit_y = new_limit_y;
345  upper_limit_y = previous_limit_y;
346  }
347 
348  // PCL_DEBUG ("Limit Y: [%f - %f]\n", lower_limit_y, upper_limit_y);
349 
350  ConditionOrPtr range_cond_OR_y (new pcl::ConditionOr<PointT> ());
351  range_cond_OR_y->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::GE, previous_limit_x )));
352  range_cond_OR_y->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::LT, previous_origin_x )));
353 
354  range_cond_OR_y->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::GE, upper_limit_y))); // filtered dimension
355  range_cond_OR_y->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::LT, lower_limit_y ))); // filtered dimension
356 
357  range_cond_OR_y->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::GE, previous_limit_z)));
358  range_cond_OR_y->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::LT, previous_origin_z )));
359 
360  pcl::ConditionalRemoval<PointT> condrem_y (true);
361  condrem_y.setCondition (range_cond_OR_y);
362  condrem_y.setInputCloud (world_);
363  condrem_y.setKeepOrganized (false);
364  // apply filter
365  condrem_y.filter (*slice);
366  IndicesConstPtr indices_y = condrem_y.getRemovedIndices ();
367 
368  //set outliers (so our slice points) to nan
369  setIndicesAsNans(world_, indices_y);
370  // PCL_DEBUG ("%d points set to nan on Y\n", indices_y->size ());
371 
372  // get points of slice on Z (we actually set a negative filter and set the ouliers (so, our slice points) to nan)
373  double lower_limit_z, upper_limit_z;
374  if(offset_z >=0)
375  {
376  lower_limit_z = previous_origin_z;
377  upper_limit_z = new_origin_z;
378  }
379  else
380  {
381  lower_limit_z = new_limit_z;
382  upper_limit_z = previous_limit_z;
383  }
384 
385  // PCL_DEBUG ("Limit Z: [%f - %f]\n", lower_limit_z, upper_limit_z);
386 
387  ConditionOrPtr range_cond_OR_z (new pcl::ConditionOr<PointT> ());
388  range_cond_OR_z->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::GE, previous_limit_x )));
389  range_cond_OR_z->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("x", pcl::ComparisonOps::LT, previous_origin_x )));
390 
391  range_cond_OR_z->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::GE, previous_limit_y)));
392  range_cond_OR_z->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("y", pcl::ComparisonOps::LT, previous_origin_y )));
393 
394  range_cond_OR_z->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::GE, upper_limit_z))); // filtered dimension
395  range_cond_OR_z->addComparison (FieldComparisonConstPtr (new pcl::FieldComparison<PointT> ("z", pcl::ComparisonOps::LT, lower_limit_z ))); // filtered dimension
396 
397  pcl::ConditionalRemoval<PointT> condrem_z (true);
398  condrem_z.setCondition (range_cond_OR_z);
399  condrem_z.setInputCloud (world_);
400  condrem_z.setKeepOrganized (false);
401  // apply filter
402  condrem_z.filter (*slice);
403  IndicesConstPtr indices_z = condrem_z.getRemovedIndices ();
404 
405  //set outliers (so our slice points) to nan
406  setIndicesAsNans(world_, indices_z);
407  // PCL_DEBUG("%d points set to nan on Z\n", indices_z->size ());
408 
409 
410 }
411 
412 #define PCL_INSTANTIATE_WorldModel(T) template class PCL_EXPORTS pcl::kinfuLS::WorldModel<T>;
413 
414 #endif // PCL_WORLD_MODEL_IMPL_HPP_
ConditionalRemoval filters data that satisfies certain conditions.
void setCondition(ConditionBasePtr condition)
Set the condition that the filter will use.
void setKeepOrganized(bool val)
Set whether the filtered points should be kept and set to the value given through setUserFilterValue ...
The field-based specialization of the comparison object.
void filter(PointCloud &output)
Calls the filtering method and returns the filtered dataset in output.
Definition: filter.h:121
IndicesConstPtr const getRemovedIndices() const
Get the point indices being removed.
Definition: filter.h:103
virtual void setInputCloud(const PointCloudConstPtr &cloud)
Provide a pointer to the input dataset.
Definition: pcl_base.hpp:65
PointCloud represents the base class in PCL for storing collections of 3D points.
Definition: point_cloud.h:173
bool empty() const
Definition: point_cloud.h:446
WorldModel maintains a 3D point cloud that can be queried and updated via helper functions.
Definition: world_model.h:63
typename PointCloud::Ptr PointCloudPtr
Definition: world_model.h:70
void setSliceAsNans(const double origin_x, const double origin_y, const double origin_z, const double offset_x, const double offset_y, const double offset_z, const int size_x, const int size_y, const int size_z)
Give nan values to the slice of the world.
void getWorldAsCubes(double size, std::vector< PointCloudPtr > &cubes, std::vector< Eigen::Vector3f, Eigen::aligned_allocator< Eigen::Vector3f > > &transforms, double overlap=0.0)
Returns the world as two vectors of cubes of size "size" (pointclouds) and transforms.
typename pcl::FieldComparison< PointT >::ConstPtr FieldComparisonConstPtr
Definition: world_model.h:75
void getExistingData(const double previous_origin_x, const double previous_origin_y, const double previous_origin_z, const double offset_x, const double offset_y, const double offset_z, const double volume_x, const double volume_y, const double volume_z, pcl::PointCloud< PointT > &existing_slice)
Retrieve existing data from the world model, after a shift.
Definition: world_model.hpp:63
typename pcl::ConditionAnd< PointT >::Ptr ConditionAndPtr
Definition: world_model.h:73
void addSlice(const PointCloudPtr new_cloud)
Append a new point cloud (slice) to the world.
Definition: world_model.hpp:47
typename pcl::ConditionOr< PointT >::Ptr ConditionOrPtr
Definition: world_model.h:74
void getMinMax3D(const pcl::PointCloud< PointT > &cloud, PointT &min_pt, PointT &max_pt)
Get the minimum and maximum values on each of the 3 (x-y-z) dimensions in a given pointcloud.
Definition: common.hpp:295
void transformPointCloud(const pcl::PointCloud< PointT > &cloud_in, pcl::PointCloud< PointT > &cloud_out, const Eigen::Matrix< Scalar, 4, 4 > &transform, bool copy_all_fields)
Apply a rigid transform defined by a 4x4 matrix.
Definition: transforms.hpp:221
void removeNaNFromPointCloud(const pcl::PointCloud< PointT > &cloud_in, pcl::PointCloud< PointT > &cloud_out, Indices &index)
Removes points with x, y, or z equal to NaN.
Definition: filter.hpp:46
shared_ptr< const Indices > IndicesConstPtr
Definition: pcl_base.h:59
IndicesAllocator<> Indices
Type used for indices in PCL.
Definition: types.h:133
A point structure representing Euclidean xyz coordinates, and the RGB color.