VTK筆記-多邊形-點/點雲繪制-vtkVertexGlyphFilter類

vtkVertexGlyphFilter

  vtkVertexGlyphFilter類的功能是建立一個多邊形資料

vtkPolyData

，其中每個點都被建立了一個頂點

Vertex

；

  vtkVertexGlyphFilter類将丢棄輸入資料中的所有單元，取而代之的是在每個點上建立一個頂點。此過濾器的預期用途大緻相當于vtkGlyph3D類，但此過濾器專門用于具有多個頂點的資料，使渲染結果比glyph過濾器更快、更不混亂。此過濾器可以将圖形或點集作為輸入。

  vtkVertexGlyphFilter類的接口基本上是使用繼承自vtkPolyDataAlgorithm類的接口；

class VTKFILTERSGENERAL_EXPORT vtkVertexGlyphFilter : public vtkPolyDataAlgorithm
{
public:
   vtkTypeMacro(vtkVertexGlyphFilter, vtkPolyDataAlgorithm);
   void PrintSelf(ostream& os, vtkIndent indent) override;
   static vtkVertexGlyphFilter* New();
  
protected:
   vtkVertexGlyphFilter();
   ~vtkVertexGlyphFilter() override;
  
   int RequestData(vtkInformation*, vtkInformationVector**, vtkInformationVector*) override;
   int FillInputPortInformation(int, vtkInformation*) override;
  
private:
   vtkVertexGlyphFilter(const vtkVertexGlyphFilter&) = delete;
   void operator=(const vtkVertexGlyphFilter&) = delete;
};  
           

臉資料-點顯示

  代碼目标：從vtk檔案中讀取離散點集合并展示；

  步驟：

    1.讀取

fran_cut.vtk

檔案，擷取其中的點資料，不要線和單元資訊；

    2.使用

vtkVertexGlyphFilter

在每個點建立一個頂點

Vertex

；

    3.使用渲染管線渲染繪制；

#include "vtkAutoInit.h" 
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);

#include <vtkPolyDataReader.h>
#include <vtkVertexGlyphFilter.h>
using namespace std;
int main() {
	vtkNew<vtkPolyDataReader> reader;
	reader->SetFileName("C:\\Data\\VTK\\fran_cut.vtk");
	reader->Update();

	vtkNew<vtkPolyData> points;
	points->SetPoints(reader->GetOutput()->GetPoints());
	vtkNew<vtkVertexGlyphFilter> vertexGlyphFilter;
	vertexGlyphFilter->AddInputData(points);
	vertexGlyphFilter->Update();
	
	vtkNew<vtkPolyDataMapper> pointMapper;
	pointMapper->SetInputData(vertexGlyphFilter->GetOutput());
	pointMapper->ScalarVisibilityOff();

	vtkNew<vtkActor> pointActor;
	pointActor->SetMapper(pointMapper);
	pointActor->GetProperty()->SetColor(1, 1, 1);
	pointActor->GetProperty()->SetPointSize(3);
	
	vtkNew<vtkRenderer> render;
	render->AddActor(pointActor);
	render->SetBackground(0.2, 0.3, 0.4);

	vtkNew<vtkRenderWindow> ren_win;
	ren_win->AddRenderer(render);

	vtkNew<vtkRenderWindowInteractor> iren;
	iren->SetRenderWindow(ren_win);
	iren->Initialize();
	iren->Start();
	return 0; 
}
           

茶壺資料-點顯示

  

TeapotPoints.txt

檔案中每行有三個浮點型的數，表示了一個點的坐标

(x,y,z)

；如下圖：

  步驟：

    1.從

TeapotPoints.txt

檔案中周遊所有點，放入

vtkPoints

；

    2.建立一個

vtkPolyData

多邊形資料，将

vtkPoints

點集合放入其中；

    3.使用

vtkVertexGlyphFilter

在每個點建立一個頂點

Vertex

；

    4.使用渲染管線渲染繪制；

int main() {
	std::string filename = "C:\\Data\\VTK\\TeapotPoints.txt";
	std::ifstream filestream(filename.c_str());

	std::string line;
	vtkNew<vtkPoints> points;

	while (std::getline(filestream, line))
	{
		double x, y, z;
		std::stringstream linestream;
		linestream << line;
		linestream >> x >> y >> z;

		points->InsertNextPoint(x, y, z);
	}
	vtkNew<vtkPolyData> pointsPolydata;
	pointsPolydata->SetPoints(points);

	vtkNew<vtkVertexGlyphFilter> vertexGlyphFilter;
	vertexGlyphFilter->AddInputData(pointsPolydata);
	vertexGlyphFilter->Update();
	vtkNew<vtkPolyDataMapper> pointMapper;
	pointMapper->SetInputData(vertexGlyphFilter->GetOutput());
	//pointMapper->ScalarVisibilityOff();

	vtkNew<vtkActor> pointActor;
	pointActor->SetMapper(pointMapper);
	pointActor->GetProperty()->SetColor(1, 1, 1);
	pointActor->GetProperty()->SetPointSize(3);
	
	vtkNew<vtkRenderer> render;
	render->AddActor(pointActor);
	render->SetBackground(0.2, 0.3, 0.4);

	vtkNew<vtkRenderWindow> ren_win;
	ren_win->AddRenderer(render);

	vtkNew<vtkRenderWindowInteractor> iren;
	iren->SetRenderWindow(ren_win);
	iren->Initialize();
	iren->Start();
	return 0; 
}