I'm developing a 3D environment using VC++ and OSG and I need some help
I'm using this code below to charge the 3D models for the scene
mueble00Node = osgDB::readNodeFile("Model/mueble_desk.3ds");
mueble00Transform = new osg::MatrixTransform;
mueble00Transform->setName("mueble00");
mueble00Transform->setDataVariance(osg::Object::STATIC);
mueble00Transform->addChild(mueble00Node);
sceneRoot->addChild(mueble00Transform);
I've tried with some lines to rotate the 3D models, but with no result
Could anybody explain to me how to rotate the models on its own axis?
Use MatrixTransform::setMatrix() to change the orientation of the child node.
MatrixTransform* transform = new osg::MatrixTransform;
const double angle = 0.8;
const Vec3d axis(0, 0, 1);
transform->setMatrix(Matrix::rotate(angle, axis));
Below is a complete program that loads and displays a 3D object with and without the transformation added.
#include <string>
#include <osg/Object>
#include <osg/Node>
#include <osg/Transform>
#include <osg/Matrix>
#include <osg/MatrixTransform>
#include <osgDB/ReadFile>
#include <osgViewer/Viewer>
#include <osgGA/TrackballManipulator>
using namespace osg;
int main(int argc, char** argv)
{
if (argc != 2) {
std::cerr << "Usage: " << argv[0] << "<file>\n";
exit(1);
}
const std::string file = argv[1];
// Load a node.
Node* node = osgDB::readNodeFile(file);
if (!node) {
std::cerr << "Can't load node from file '" << file << "'\n";
exit(1);
}
// Set a transform for the node.
MatrixTransform* transform = new osg::MatrixTransform;
const double angle = 0.8;
const Vec3d axis(0, 0, 1);
transform->setMatrix(Matrix::rotate(angle, axis));
transform->setName(file);
transform->addChild(node);
// Add the node with and without the transform.
Group* scene = new Group();
scene->addChild(transform);
scene->addChild(node);
// Start a scene graph viewer.
osgViewer::Viewer viewer;
viewer.setSceneData(scene);
viewer.setCameraManipulator(new osgGA::TrackballManipulator());
viewer.realize();
while (!viewer.done()) viewer.frame();
}
You'll want to use a quat
http://www.openscenegraph.org/documentation/OpenSceneGraphReferenceDocs/a00568.html
It has a number of functions you can use for rotation.
Related
I want to simplify a surface read from .off file and view it using CGAL.
I read the surface as Polyhedron_3 and I want to convert it to Linear_cell_complex_for_combinatorial_map to view it but there is a problem in import_from_polyhedron_3 method
my code:
typedef CGAL::Linear_cell_complex_for_combinatorial_map<2,3> LCC_3;
typedef LCC_3::Dart_handle Dart_handle;
typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;
typedef CGAL::Polyhedron_3<Kernel> Polyhedron;
QWidget* viewer ;
QString fileName;
LCC_3 lcc;
QMainWindow qWin;
CGAL::DefaultColorFunctorLCC fcolor;
Polyhedron P;
void MainWindow::preview()
{
QWidget* centralWidget = new QWidget(viewer);
centralWidget->setSizePolicy(QSizePolicy::Maximum,QSizePolicy::Maximum);
CGAL::import_from_polyhedron_3<LCC_3, Polyhedron>(lcc, P);
setCentralWidget( new CGAL::SimpleLCCViewerQt<LCC_3, CGAL::DefaultColorFunctorLCC>(&qWin ,
lcc,
"Basic LCC Viewer",
false,
fcolor ) );
show();
}
void MainWindow::fileOpen()
{
fileName = QFileDialog::getOpenFileName(this,tr("Select object"), ".", tr("*.off"));
std::ofstream out(fileName.toLocal8Bit());
out<<P;
preview();
}
void MainWindow ::simplify()
{
bool ok;
int n = QInputDialog::getInt(this, "", tr("Number of vertices in each cell:"),P.size_of_vertices(),0, P.size_of_vertices(),1, &ok);
if (ok){
int r = P.size_of_vertices() - n;
int target_edges = P.size_of_halfedges()/2 - r*3;
n=target_edges+1;
}
typedef CGAL::Polyhedron_3<Kernel> Surface;
SaveOFF("temp.off");
namespace SMS = CGAL::Surface_mesh_simplification ;
Surface surface;
std::ifstream is("temp.off") ; is >> surface ;
// This is a stop predicate (defines when the algorithm terminates).
// In this example, the simplification stops when the number of undirected edges
// left in the surface drops below the specified number (1000)
SMS::Count_stop_predicate<Surface> stop(n);
// This the actual call to the simplification algorithm.
// The surface and stop conditions are mandatory arguments.
// The index maps are needed because the vertices and edges
// of this surface lack an "id()" field.
int r = SMS::edge_collapse
(surface
,stop
,CGAL::parameters::vertex_index_map(get(CGAL::vertex_external_index,surface))
.halfedge_index_map (get(CGAL::halfedge_external_index ,surface))
);
std::ofstream os("temp.off"); os << surface ;
OpenOFF("temp.off");
std::cout << "Finished..." << r << " edges removed."<<std::endl;
std::cout<<P.size_of_vertices()<<" Vertices"<<std::endl;
std::cout<<P.size_of_facets()<<" Facets"<<std::endl;
std::cout<<P.size_of_halfedges()<<" Halfedges"<<std::endl;
preview();
}
it shows me the following error:
‘import_from_polyhedron_3’ is not a member of ‘CGAL’
CGAL::import_from_polyhedron_3(lcc, P);
another problem it cannot reload the surface in the viewer after simplifying it , it shows the following error :
it's shows error "The inferior stopped because it received a signal from the operating system."
I need any help please
thanks
Missing #include< CGAL/Polyhedron_3_to_lcc.h > (cf doc here)
TL;DR
I have a pipeline which reads an image and displays a mesh using VTK; upon changing the input to the image reader and updating the pipeline, the mesh doesn't update until I interact with the window.
The Long Version
I have a directory with a sequence of segmentation files (i.e., 3D image volumes where pixel values correspond to structures in a corresponding image) which show how a structure changes over time. I've written a utility in VTK which allows me to load the first image in the directory, visualize a label as a mesh, and "step" forwards or backwards using the arrow keys by changing the file name of the input image and updating the pipeline. This very nearly works--the only issue is that, after updating the pipeline, the meshes don't update until I interact with the window (simply clicking anywhere in the window causes the mesh to update, for example).
What I've Tried:
Calling Update() on the reader:
this->reader->Update();
Calling Modified() on the actors:
const auto actors = this->GetCurrentRenderer()->GetActors();
actors->InitTraversal();
for (vtkIdType i = 0; i < actors->GetNumberOfItems(); ++i)
{
actors->GetNextActor()->Modified();
}
Calling Render() on the current render window:
this->GetCurrentRenderer()->Render();
MCVE:
NOTE: the reader is updated in KeyPressInteractorStyle::UpdateReader().
// VTK
#include <vtkSmartPointer.h>
#include <vtkNIFTIImageReader.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkCamera.h>
#include <vtkDiscreteMarchingCubes.h>
#include <vtkProperty.h>
#include <vtkInteractorStyleTrackballCamera.h>
// Define interaction style
class KeyPressInteractorStyle : public vtkInteractorStyleTrackballCamera
{
public:
static KeyPressInteractorStyle* New();
vtkTypeMacro(KeyPressInteractorStyle, vtkInteractorStyleTrackballCamera);
virtual void OnKeyPress()
{
// Get the keypress
vtkRenderWindowInteractor *rwi = this->Interactor;
std::string key = rwi->GetKeySym();
// Output the key that was pressed
std::cout << "Pressed " << key << std::endl;
// Handle an arrow key
if(key == "Down" || key == "Right")
{
this->index += 1;
this->UpdateReader();
}
// Handle an arrow key
if(key == "Up" || key == "Left")
{
this->index -= 1;
this->UpdateReader();
}
// Forward events
vtkInteractorStyleTrackballCamera::OnKeyPress();
}
void UpdateReader()
{
std::cout << "Frame: " << this->index << std::endl;
const auto fn = this->directory + std::to_string(this->index) + ".nii.gz";
std::cout << fn << std::endl;
this->reader->SetFileName( fn.c_str() );
this->reader->Update();
const auto actors = this->GetCurrentRenderer()->GetActors();
actors->InitTraversal();
for (vtkIdType i = 0; i < actors->GetNumberOfItems(); ++i)
{
actors->GetNextActor()->Modified();
}
this->GetCurrentRenderer()->Render();
}
unsigned int index = 0;
std::string directory;
vtkSmartPointer<vtkNIFTIImageReader> reader;
};
vtkStandardNewMacro(KeyPressInteractorStyle);
int
main( int argc, char ** argv )
{
std::string dn = argv[1];
const auto renderer = vtkSmartPointer<vtkRenderer>::New();
unsigned int frameid = 0;
const auto reader = vtkSmartPointer<vtkNIFTIImageReader>::New();
reader->SetFileName( (dn + std::to_string(frameid) + ".nii.gz").c_str() );
const auto cubes = vtkSmartPointer<vtkDiscreteMarchingCubes>::New();
cubes->SetInputConnection( reader->GetOutputPort() );
cubes->SetValue( 0, 1 );
const auto mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
mapper->SetInputConnection( cubes->GetOutputPort() );
mapper->ScalarVisibilityOff();
const auto actor = vtkSmartPointer<vtkActor>::New();
actor->SetMapper( mapper );
renderer->AddActor( actor );
const auto window = vtkSmartPointer<vtkRenderWindow>::New();
window->AddRenderer( renderer );
const auto interactor = vtkSmartPointer<vtkRenderWindowInteractor>::New();
const auto style = vtkSmartPointer<KeyPressInteractorStyle>::New();
style->reader = reader;
style->directory = dn;
interactor->SetInteractorStyle( style );
style->SetCurrentRenderer( renderer );
interactor->SetRenderWindow( window );
window->Render();
interactor->Start();
return EXIT_SUCCESS;
}
You have actually not tried to call Render() on the current render window, you are calling it on the current renderer, which are two different things. As the documentation of vtkRenderer::Renderer() states,
CALLED BY vtkRenderWindow ONLY.
End-user pass your way and call vtkRenderWindow::Render(). Create an
image. This is a superclass method which will in turn call the
DeviceRender method of Subclasses of vtkRenderer.
So change this->GetCurrentRenderer()->Render(); to this->GetCurrentRenderer()->GetRenderWindow()->Render();
I am trying to run some software I found on github. I managed to compile and install everything on my ubuntu machine. However when trying to run one of the provided examples (fit-model-simple.cpp) I get the following error:
Error loading the Morphable Model: Error opening given file: ../share/sfm_shape_3448.bin
I tried to hard code the path to the file as well but the result stays the same.
Does anybody know what I might be doing wrong?
This is the code:
/*
* eos - A 3D Morphable Model fitting library written in modern C++11/14.
*
* File: examples/fit-model-simple.cpp
*
* Copyright 2015 Patrik Huber
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "eos/core/Landmark.hpp"
#include "eos/core/LandmarkMapper.hpp"
#include "eos/fitting/orthographic_camera_estimation_linear.hpp"
#include "eos/fitting/RenderingParameters.hpp"
#include "eos/fitting/linear_shape_fitting.hpp"
#include "eos/render/utils.hpp"
#include "eos/render/texture_extraction.hpp"
#include "opencv2/core/core.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "boost/program_options.hpp"
#include "boost/filesystem.hpp"
#include <vector>
#include <iostream>
#include <fstream>
using namespace eos;
namespace po = boost::program_options;
namespace fs = boost::filesystem;
using eos::core::Landmark;
using eos::core::LandmarkCollection;
using cv::Mat;
using cv::Vec2f;
using cv::Vec3f;
using cv::Vec4f;
using std::cout;
using std::endl;
using std::vector;
using std::string;
/**
* Reads an ibug .pts landmark file and returns an ordered vector with
* the 68 2D landmark coordinates.
*
* #param[in] filename Path to a .pts file.
* #return An ordered vector with the 68 ibug landmarks.
*/
LandmarkCollection<cv::Vec2f> read_pts_landmarks(std::string filename)
{
using std::getline;
using cv::Vec2f;
using std::string;
LandmarkCollection<Vec2f> landmarks;
landmarks.reserve(68);
std::ifstream file(filename);
if (!file.is_open()) {
throw std::runtime_error(string("Could not open landmark file: " + filename));
}
string line;
// Skip the first 3 lines, they're header lines:
getline(file, line); // 'version: 1'
getline(file, line); // 'n_points : 68'
getline(file, line); // '{'
int ibugId = 1;
while (getline(file, line))
{
if (line == "}") { // end of the file
break;
}
std::stringstream lineStream(line);
Landmark<Vec2f> landmark;
landmark.name = std::to_string(ibugId);
if (!(lineStream >> landmark.coordinates[0] >> landmark.coordinates[1])) {
throw std::runtime_error(string("Landmark format error while parsing the line: " + line));
}
// From the iBug website:
// "Please note that the re-annotated data for this challenge are saved in the Matlab convention of 1 being
// the first index, i.e. the coordinates of the top left pixel in an image are x=1, y=1."
// ==> So we shift every point by 1:
landmark.coordinates[0] -= 1.0f;
landmark.coordinates[1] -= 1.0f;
landmarks.emplace_back(landmark);
++ibugId;
}
return landmarks;
};
/**
* This app demonstrates estimation of the camera and fitting of the shape
* model of a 3D Morphable Model from an ibug LFPW image with its landmarks.
*
* First, the 68 ibug landmarks are loaded from the .pts file and converted
* to vertex indices using the LandmarkMapper. Then, an orthographic camera
* is estimated, and then, using this camera matrix, the shape is fitted
* to the landmarks.
*/
int main(int argc, char *argv[])
{
std::cerr<<"modif 1"<<endl;
fs::path modelfile, isomapfile, imagefile, landmarksfile, mappingsfile, outputfile;
try {
po::options_description desc("Allowed options");
desc.add_options()
("help,h",
"display the help message")
("model,m", po::value<fs::path>(&modelfile)->required()->default_value("/home/yalishanda/Downloads/eos-master/share/sfm_shape_3448.bin"),
"a Morphable Model stored as cereal BinaryArchive")
("image,i", po::value<fs::path>(&imagefile)->required()->default_value("/home/yalishanda/Downloads/eos-master/examples/data/image_0010.png"),
"an input image")
("landmarks,l", po::value<fs::path>(&landmarksfile)->required()->default_value("/home/yalishanda/Downloads/eos-master/examples/data/image_0010.pts"),
"2D landmarks for the image, in ibug .pts format")
("mapping,p", po::value<fs::path>(&mappingsfile)->required()->default_value("/home/yalishanda/Downloads/eos-master/share/ibug_to_sfm.txt"),
"landmark identifier to model vertex number mapping")
("output,o", po::value<fs::path>(&outputfile)->required()->default_value("out"),
"basename for the output rendering and obj files")
;
po::variables_map vm;
po::store(po::command_line_parser(argc, argv).options(desc).run(), vm);
if (vm.count("help")) {
cout << "Usage: fit-model-simple [options]" << endl;
cout << desc;
return EXIT_SUCCESS;
}
po::notify(vm);
}
catch (const po::error& e) {
cout << "Error while parsing command-line arguments: " << e.what() << endl;
cout << "Use --help to display a list of options." << endl;
return EXIT_FAILURE;
}
// Load the image, landmarks, LandmarkMapper and the Morphable Model:
Mat image = cv::imread(imagefile.string());
LandmarkCollection<cv::Vec2f> landmarks;
try {
landmarks = read_pts_landmarks(landmarksfile.string());
}
catch (const std::runtime_error& e) {
cout << "Error reading the landmarks: " << e.what() << endl;
return EXIT_FAILURE;
}
morphablemodel::MorphableModel morphable_model;
try {
morphable_model = morphablemodel::load_model(modelfile.string());
}
catch (const std::runtime_error& e) {
cout << "Error loading the Morphable Model: " << e.what() << endl;
return EXIT_FAILURE;
}
core::LandmarkMapper landmark_mapper = mappingsfile.empty() ? core::LandmarkMapper() : core::LandmarkMapper(mappingsfile);
// Draw the loaded landmarks:
Mat outimg = image.clone();
for (auto&& lm : landmarks) {
cv::rectangle(outimg, cv::Point2f(lm.coordinates[0] - 2.0f, lm.coordinates[1] - 2.0f), cv::Point2f(lm.coordinates[0] + 2.0f, lm.coordinates[1] + 2.0f), { 255, 0, 0 });
}
// These will be the final 2D and 3D points used for the fitting:
vector<Vec4f> model_points; // the points in the 3D shape model
vector<int> vertex_indices; // their vertex indices
vector<Vec2f> image_points; // the corresponding 2D landmark points
// Sub-select all the landmarks which we have a mapping for (i.e. that are defined in the 3DMM):
for (int i = 0; i < landmarks.size(); ++i) {
auto converted_name = landmark_mapper.convert(landmarks[i].name);
if (!converted_name) { // no mapping defined for the current landmark
continue;
}
int vertex_idx = std::stoi(converted_name.get());
auto vertex = morphable_model.get_shape_model().get_mean_at_point(vertex_idx);
model_points.emplace_back(Vec4f(vertex.x(), vertex.y(), vertex.z(), 1.0f));
vertex_indices.emplace_back(vertex_idx);
image_points.emplace_back(landmarks[i].coordinates);
}
// Estimate the camera (pose) from the 2D - 3D point correspondences
fitting::ScaledOrthoProjectionParameters pose = fitting::estimate_orthographic_projection_linear(image_points, model_points, true, image.rows);
fitting::RenderingParameters rendering_params(pose, image.cols, image.rows);
// The 3D head pose can be recovered as follows:
float yaw_angle = glm::degrees(glm::yaw(rendering_params.get_rotation()));
// and similarly for pitch and roll.
// Estimate the shape coefficients by fitting the shape to the landmarks:
Mat affine_from_ortho = fitting::get_3x4_affine_camera_matrix(rendering_params, image.cols, image.rows);
vector<float> fitted_coeffs = fitting::fit_shape_to_landmarks_linear(morphable_model, affine_from_ortho, image_points, vertex_indices);
// Obtain the full mesh with the estimated coefficients:
core::Mesh mesh = morphable_model.draw_sample(fitted_coeffs, vector<float>());
// Extract the texture from the image using given mesh and camera parameters:
Mat isomap = render::extract_texture(mesh, affine_from_ortho, image);
// Save the mesh as textured obj:
outputfile += fs::path(".obj");
core::write_textured_obj(mesh, outputfile.string());
// And save the isomap:
outputfile.replace_extension(".isomap.png");
cv::imwrite(outputfile.string(), isomap);
cout << "Finished fitting and wrote result mesh and isomap to files with basename " << outputfile.stem().stem() << "." << endl;
return EXIT_SUCCESS;
}
It might because you run it directly without generating it as a project. Check eos documentation:
git clone --recursive https://github.com/patrikhuber/eos.git
mkdir build && cd build # creates a build directory next to the 'eos' folder
cmake -G "<your favourite generator>" ../eos -DCMAKE_INSTALL_PREFIX=../install/
make && make install # or open the project file and build in an IDE like Visual Studio
Or it might due to files haven't loaded successfully after your git clone
Hope it helps!
Intention
I wrote a VTK application that generates a spiral using vtkPoints > vtkPolyLine > vtkPolyData > vtkPolyDataMapper and displays it. This works fine, if done static at the initialization of the program.
Now, I want to add new data points dynamically. The intention is to visualize measurements in real time, so new data will be added in certain intervals.
Issues
Currently, I just implemented a TimerEvent to update the vtkPoints and vtkPolyLine. But, the program just shows the static data generated before the vtkRenderWindowInteractor was started. I also tried to use "Modified()" and "Update()" calls to nearly all objects, tried to remove, regenerate and add a new actor to the renderer -- but without success! I added my C++ code below...
Related-Questions
The following mailing list question is about this issues, but the solution given doen't work for me:
http://public.kitware.com/pipermail/vtkusers/2006-November/038377.html
The following question seems to be related, but there are no useful answers:
VTK: update data points in renderWindow at every simulation timestep
Questions
How to tell VTK that the vtkPolyData object has changed?
Which of the VTK UsersGuide should I probably have a closer look at?
Details / Source Code
I'm using Visual Studio Community 2017 and VTK 8.0.0, both compiled as Win32 target.
#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkRenderingContextOpenGL2);
VTK_MODULE_INIT(vtkRenderingVolumeOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);
VTK_MODULE_INIT(vtkRenderingFreeType);
#include <vtkSmartPointer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkConeSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkProperty.h>
#include <vtkPoints.h>
#include <vtkPolyLine.h>
vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
vtkSmartPointer<vtkPolyLine> polyLine = vtkSmartPointer<vtkPolyLine>::New();
int numOfPoints = 0;
double t = 0;
void NextPoint() {
double x = t * cos(t);
double y = t * sin(t);
points->InsertNextPoint(x, y, t);
polyLine->GetPointIds()->InsertNextId(numOfPoints);
numOfPoints++;
t += 0.1;
}
vtkSmartPointer<vtkPolyData> generateEllipse() {
// Add some points so we actually see something at all...
for (int i = 0; i < 100; ++i) {
NextPoint();
}
vtkSmartPointer<vtkCellArray> cells = vtkSmartPointer<vtkCellArray>::New();
cells->InsertNextCell(polyLine);
vtkSmartPointer<vtkPolyData> polyData = vtkSmartPointer<vtkPolyData>::New();
polyData->SetPoints(points);
polyData->SetLines(cells);
return polyData;
}
class vtkTimerCallback : public vtkCommand
{
public:
static vtkTimerCallback *New()
{
vtkTimerCallback *cb = new vtkTimerCallback;
cb->TimerCount = 0;
return cb;
}
virtual void Execute(vtkObject *vtkNotUsed(caller), unsigned long eventId,
void *vtkNotUsed(callData))
{
if (vtkCommand::TimerEvent == eventId)
{
NextPoint(); // Add another point to polyData
++this->TimerCount;
cout << this->TimerCount << endl;
}
}
private:
int TimerCount;
};
int main(int argc, char** argv) {
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
vtkSmartPointer<vtkRenderWindowInteractor> rwi = vtkSmartPointer<vtkRenderWindowInteractor>::New();
rwi->SetRenderWindow(renderWindow);
vtkSmartPointer<vtkPolyData> data = generateEllipse();
vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
mapper->SetInputData(data);
vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
actor->SetMapper(mapper);
actor->GetProperty()->SetDiffuseColor(255, 255, 0);
vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
renderWindow->AddRenderer(renderer);
renderer->AddActor(actor);
renderer->ResetCamera();
renderWindow->Render();
// Add Timer Event...
rwi->Initialize();
vtkSmartPointer<vtkTimerCallback> cb = vtkSmartPointer<vtkTimerCallback>::New();
rwi->AddObserver(vtkCommand::TimerEvent, cb);
int timerId = rwi->CreateRepeatingTimer(100); // every 100ms
std::cout << "timerId: " << timerId << std::endl;
// Start Displaying...
rwi->Start();
return 0;
}
the problem is that the cells are not stored by pointer - when you call cells->InsertNextCell(polyLine); the data is copied, not pointed to, in order to create an efficient storage of the cells in an array (the whole implementation is actually in the header of vtkCellArray so you can check it out). So then when you update polyLine, it has no effect in the polydata, because the polydata have their own copy that you did not update. The following code works for me (you have to expose the polydata and the cellArray):
virtual void Execute(vtkObject *vtkNotUsed(caller), unsigned long eventId,
void *vtkNotUsed(callData))
{
if (vtkCommand::TimerEvent == eventId)
{
NextPoint(); // Add another point to polyData
cells->Initialize(); // reset the cells to remove the old spiral
cells->InsertNextCell(polyLine); // re-insert the updated spiral
cells->Modified(); // required to update
data->Modified(); // required to update
++this->TimerCount;
cout << polyLine->GetNumberOfPoints() << endl;
renderWindow->Render(); // refresh the render window after each update
}
}
Yesterday I worked out an alternative solution using a vtkProgrammableDataObjectSource as DataSource. Tomj's solution is the more direct and simple solution... However, there is no C++ Example Code at vtk.org that explains how to use vtkProgrammableDataObjectSource and I had to work it out by trial and error. So I'll post it here, as it might help others:
#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkRenderingContextOpenGL2);
VTK_MODULE_INIT(vtkRenderingVolumeOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);
VTK_MODULE_INIT(vtkRenderingFreeType);
#include <vtkSmartPointer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkConeSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkProperty.h>
#include <vtkPoints.h>
#include <vtkPolyLine.h>
#include <vtkProgrammableFilter.h>
#include <vtkCallbackCommand.h>
#include <vtkPolyDataStreamer.h>
#include <vtkProgrammableDataObjectSource.h>
vtkSmartPointer<vtkProgrammableDataObjectSource> pDOS = vtkSmartPointer<vtkProgrammableDataObjectSource>::New();
vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
vtkSmartPointer<vtkPolyLine> polyLine = vtkSmartPointer<vtkPolyLine>::New();
int numOfPoints = 0;
double t = 0;
void NextPoint() {
double x = t * cos(t);
double y = t * sin(t);
points->InsertNextPoint(x, y, t);
polyLine->GetPointIds()->InsertNextId(numOfPoints);
numOfPoints++;
t += 0.1;
}
void generateEllipse(void *caller) {
vtkProgrammableDataObjectSource *pDOS = vtkProgrammableDataObjectSource::SafeDownCast((vtkObjectBase*)caller);
vtkSmartPointer<vtkCellArray> cells = vtkSmartPointer<vtkCellArray>::New();
cells->InsertNextCell(polyLine);
vtkSmartPointer<vtkPolyData> polyData = vtkSmartPointer<vtkPolyData>::New();
polyData->SetPoints(points);
polyData->SetLines(cells);
pDOS->SetOutput(polyData);
}
int counter2 = 0;
void TimerCallbackFunction(vtkObject* caller, long unsigned int vtkNotUsed(eventId), void* clientData, void* vtkNotUsed(callData)) {
cout << "timer callback: " << counter2 << endl;
// To avoid globals we can implement this later...
// vtkSmartPointer<vtkProgrammableDataObjectSource> pDOS =
// static_cast<vtkProgrammableDataObjectSource*>(clientData);
vtkRenderWindowInteractor *rwi =
static_cast<vtkRenderWindowInteractor*>(caller);
NextPoint();
pDOS->Modified();
rwi->Render();
renderer->ResetCamera(); // Optional: Reposition Camera, so it displays the whole object
counter2++;
}
int main(int argc, char** argv) {
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
vtkSmartPointer<vtkRenderWindowInteractor> rwi = vtkSmartPointer<vtkRenderWindowInteractor>::New();
rwi->SetRenderWindow(renderWindow);
pDOS->SetExecuteMethod(&generateEllipse, pDOS);
vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
mapper->SetInputConnection(pDOS->GetOutputPort());
vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
actor->SetMapper(mapper);
actor->GetProperty()->SetDiffuseColor(255, 255, 0);
renderWindow->AddRenderer(renderer);
renderer->AddActor(actor);
renderer->ResetCamera();
renderWindow->Render();
// Add Timer Event...
vtkSmartPointer<vtkCallbackCommand> timerCallback = vtkSmartPointer<vtkCallbackCommand>::New();
timerCallback->SetCallback(TimerCallbackFunction);
rwi->Initialize();
rwi->CreateRepeatingTimer(100);
rwi->AddObserver(vtkCommand::TimerEvent, timerCallback);
// Start Displaying...
rwi->Start();
return 0;
}
I have a few objects that I want to combine into a scene graph.
Street inherits from Geode and has a Geometry child drawable made up of a GL_LINE_STRIP.
Pointer inherits from PositionAttitudeTransform and contains a Geode which contains two Geometry polygons.
When I add a bunch of Streets to a Group, it looks just fine. When I add only the Pointer to a Group, it also looks fine. But if I somehow have them both in the scene, the second one is screwed up. See the two pictures.
In the above picture, the street network is as desired, and in the picture below, the pointer is as desired.
I'd appreciate any help! If you need to see the code, let me know and I'll update my question.
Update 1: Since nothing has happened so far, here is the minimal amount of code necessary to produce the phenomenon. I have put two pointers next to each other with no problem, so I'm starting to suspect that I made the streets wrong... next update will be some street generation code.
Update 2: The code now contains the street drawing code.
Update 3: The code now contains the pointer drawing code as well, and the street drawing
code has been simplified.
// My libraries:
#include <asl/util/color.h>
using namespace asl;
#include <straph/point.h>
#include <straph/straph.h>
using namespace straph;
// Standard and OSG libraries:
#include <utility>
#include <boost/tuple/tuple.hpp> // tie
using namespace std;
#include <osg/ref_ptr>
#include <osg/Array>
#include <osg/Geometry>
#include <osg/Geode>
#include <osg/Group>
#include <osg/LineWidth>
using namespace osg;
#include <osgUtil/Tessellator>
#include <osgViewer/Viewer>
using namespace osgViewer;
/*
* Just FYI: A Polyline looks like this:
*
* typedef std::vector<Point> Polyline;
*
* And a Point basically is a simple struct:
*
* struct Point {
* double x;
* double y;
* };
*/
inline osg::Vec3d toVec3d(const straph::Point& p, double elevation=0.0)
{
return osg::Vec3d(p.x, p.y, elevation);
}
Geometry* createStreet(const straph::Polyline& path)
{
ref_ptr<Vec3dArray> array (new Vec3dArray(path.size()));
for (unsigned i = 0; i < path.size(); ++i) {
(*array)[i] = toVec3d(path[i]);
}
Geometry* geom = new Geometry;
geom->setVertexArray(array.get());
geom->addPrimitiveSet(new osg::DrawArrays(GL_LINE_STRIP, 0, array->size()));
return geom;
}
Geode* load_streets()
{
unique_ptr<Straph> graph = read_shapefile("mexico/roads", 6);
Geode* root = new Geode();
boost::graph_traits<straph::Straph>::edge_iterator ei, ee;
for (boost::tie(ei, ee) = edges(*graph); ei != ee; ++ei) {
const straph::Segment& s = (*graph)[*ei];
root->addDrawable(createStreet(s.polyline));
}
return root;
}
Geode* createPointer(double width, const Color& body_color, const Color& border_color)
{
float f0 = 0.0f;
float f3 = 3.0f;
float f1 = 1.0f * width;
float f2 = 2.0f * width;
// Create vertex array
ref_ptr<Vec3Array> vertices (new Vec3Array(4));
(*vertices)[0].set( f0 , f0 , f0 );
(*vertices)[1].set( -f1/f3, -f1/f3 , f0 );
(*vertices)[2].set( f0 , f2/f3 , f0 );
(*vertices)[3].set( f1/f3, -f1/f3 , f0 );
// Build the geometry object
ref_ptr<Geometry> polygon (new Geometry);
polygon->setVertexArray( vertices.get() );
polygon->addPrimitiveSet( new DrawArrays(GL_POLYGON, 0, 4) );
// Set the colors
ref_ptr<Vec4Array> body_colors (new Vec4Array(1));
(*body_colors)[0] = body_color.get();
polygon->setColorArray( body_colors.get() );
polygon->setColorBinding( Geometry::BIND_OVERALL );
// Start the tesselation work
osgUtil::Tessellator tess;
tess.setTessellationType( osgUtil::Tessellator::TESS_TYPE_GEOMETRY );
tess.setWindingType( osgUtil::Tessellator::TESS_WINDING_ODD );
tess.retessellatePolygons( *polygon );
// Create the border-lines
ref_ptr<Geometry> border (new Geometry);
border->setVertexArray( vertices.get() );
border->addPrimitiveSet(new DrawArrays(GL_LINE_LOOP, 0, 4));
border->getOrCreateStateSet()->setAttribute(new LineWidth(2.0f));
ref_ptr<Vec4Array> border_colors (new Vec4Array(1));
(*border_colors)[0] = border_color.get();
border->setColorArray( border_colors.get() );
border->setColorBinding( Geometry::BIND_OVERALL );
// Create Geode object
ref_ptr<Geode> geode (new Geode);
geode->addDrawable( polygon.get() );
geode->addDrawable( border.get() );
return geode.release();
}
int main(int, char**)
{
Group* root = new Group();
Geode* str = load_streets();
root->addChild(str);
Geode* p = createPointer(6.0, TangoColor::Scarlet3, TangoColor::Black);
root->addChild(p);
Viewer viewer;
viewer.setSceneData(root);
viewer.getCamera()->setClearColor(Color(TangoColor::White).get());
viewer.run();
}
In the functions createStreet I use a Vec3dArray for the vertex array, whereas in the createPointer function, I use a Vec3Array. In the library I guess it expects all nodes
to be composed of floats or doubles, but not both. Changing these two functions solves the problem:
inline osg::Vec3 toVec3(const straph::Point& p, float elevation=0.0)
{
return osg::Vec3(float(p.x), float(p.y), elevation);
}
Geometry* createStreet(const straph::Polyline& path)
{
ref_ptr<Vec3Array> array (new Vec3Array(path.size()));
for (unsigned i = 0; i < path.size(); ++i) {
(*array)[i] = toVec3(path[i]);
}
Geometry* geom = new Geometry;
geom->setVertexArray(array.get());
geom->addPrimitiveSet(new osg::DrawArrays(GL_LINE_STRIP, 0, array->size()));
return geom;
}
Here a comment by Robert Osfield:
I can only provide a guess, and that would be that the Intel OpenGL doesn't handle double vertex data correctly, so you are stumbling across a driver bug.
In general OpenGL hardware is based around floating point maths so the drivers normally convert any double data you pass it into floats before passing it to the GPU. Even if the driver does this correctly this conversion process slows performance down so it's best to keep osg::Geometry vertex/texcoord/normal etc. data all in float arrays such as Vec3Array.
You can retain precision by translating your data to a local origin prior to conversion to float then place a MatrixTransform above your data to place it in the correct 3D position. The OSG by default uses double for all internal matrices that that when it accumulates the modelvew matrix during the cull traversal double precision is maintain for as long as possible before passing the final modelview matrix to OpenGL. Using this technique the OSG can handle whole earth data without any jitter/precision problems.