Add tutorial for unicode support in pcl visualizer

[jiaobinbin152]

Original issue:
addText3D(std::string("我是谁"),position,1,255,0,0,"cubeTrackId");

don‘t work!

---

We can add a simple tutorial for unicode visualization (UTF-8, etc.). Starting link

[mvieth]

We definitely need more information to help you. In which way does it not work? Do you see an error message? A larger snippet of your code would be helpful. What PCL version do you use and how did you install it? What operating system do you use?

[WangZP10969]

@jiaobinbin152 If you mean that Chinese cannot be displayed (nothing), my experience in displaying Chinese on actor2d tells me that you can use the following code to convert string to utf8, and you need to set the font file. But for 3D text display, you can try it, I am not sure if it is feasible.

Conversion function

std::string string_To_UTF8(const std::string& String)
{
long nwLen = MultiByteToWideChar(CP_ACP, 0, String.c_str(), -1, NULL, 0);
wchar_t* pwBuf = new wchar_t[nwLen + 1];
ZeroMemory(pwBuf, nwLen * 2 + 2);
MultiByteToWideChar(CP_ACP, 0, String.c_str(), String.length(), pwBuf, nwLen);
long nLen = WideCharToMultiByte(CP_UTF8, 0, pwBuf, -1, NULL, NULL, NULL, NULL);
char* pBuf = new char[nLen + 1];
ZeroMemory(pBuf, nLen + 1);
WideCharToMultiByte(CP_UTF8, 0, pwBuf, nwLen, pBuf, nLen, NULL, NULL);
std::string retStr(pBuf);
delete[] pwBuf;
delete[] pBuf;
pwBuf = nullptr;
pBuf = nullptr;
return retStr;
}

Set font file

PointSetToLabelHierarchy->GetTextProperty()->SetFontFamily(VTK_FONT_FILE);
PointSetToLabelHierarchy->GetTextProperty()->SetFontFile("C:\\Windows\\Fonts\\msyh.ttc");

[jiaobinbin152]

We definitely need more information to help you. In which way does it not work? Do you see an error message? A larger snippet of your code would be helpful. What PCL version do you use and how did you install it? What operating system do you use?

PCL version : 1.10.1
OS : win 10
IDE : Visual Studio 2019
Code :
boost::shared_ptrpcl::visualization::PCLVisualizer viewer (new pcl::visualization::PCLVisualizer ("3D Viewer"));
viewer->removeText3D("sample text UTF8");
viewer->removeText3D("sample text");
viewer->setBackgroundColor (0, 0, 0);
viewer->addPointCloudpcl::PointXYZ (cloud, "sample cloud");
pcl::PointXYZ pointUTF8(1, 1, 1);
std::string str = string_To_UTF8(std::string("我是谁"));
viewer->addText3D(std::string("我是谁"), pointUTF8,1,255,0,0,"sample text UTF8");
pcl::PointXYZ point(1, 1, 0);
viewer->addText3D("hello world", point, 1, 255, 0, 0, "sample text");
viewer->setPointCloudRenderingProperties (pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 1, "sample cloud");
viewer->addCoordinateSystem (1.0);
viewer->initCameraParameters ();

Display:

don't find "我是谁" and no error message

[jiaobinbin152]

@jiaobinbin152 If you mean that Chinese cannot be displayed (nothing), my experience in displaying Chinese on actor2d tells me that you can use the following code to convert string to utf8, and you need to set the font file. But for 3D text display, you can try it, I am not sure if it is feasible.

Conversion function

std::string string_To_UTF8(const std::string& String)
{
long nwLen = MultiByteToWideChar(CP_ACP, 0, String.c_str(), -1, NULL, 0);
wchar_t* pwBuf = new wchar_t[nwLen + 1];
ZeroMemory(pwBuf, nwLen * 2 + 2);
MultiByteToWideChar(CP_ACP, 0, String.c_str(), String.length(), pwBuf, nwLen);
long nLen = WideCharToMultiByte(CP_UTF8, 0, pwBuf, -1, NULL, NULL, NULL, NULL);
char* pBuf = new char[nLen + 1];
ZeroMemory(pBuf, nLen + 1);
WideCharToMultiByte(CP_UTF8, 0, pwBuf, nwLen, pBuf, nLen, NULL, NULL);
std::string retStr(pBuf);
delete[] pwBuf;
delete[] pBuf;
pwBuf = nullptr;
pBuf = nullptr;
return retStr;
}

Set font file

PointSetToLabelHierarchy->GetTextProperty()->SetFontFamily(VTK_FONT_FILE);
PointSetToLabelHierarchy->GetTextProperty()->SetFontFile("C:\Windows\Fonts\msyh.ttc");

Thanks WangZP10969
try to use string_To_UTF8 , but also don’t work .

about PointSetToLabelHierarchy，I don't konw how to use? I'm only use PCLVisualizer。

[WangZP10969]

@jiaobinbin152
I saw your program
std::string str = string_To_UTF8(std::string("我是谁"));

But I don’t see "str" being used, the string after string_To_UTF8 conversion needs to be added
viewer->addText3D(str, pointUTF8,1,255,0,0,"sample text UTF8");

If you add it, the display becomes a question mark "?", then I think you need to find a way to set the fontfile.
If you add it and nothing is displayed, I think the problem you encountered is not the same as my experience.

[kunaltyagi]

@WangZP10969 This is quite a good writeup. Could you clean the code a bit, and add that as a tutorial?

[WangZP10969]

@WangZP10969 This is quite a good writeup. Could you clean the code a bit, and add that as a tutorial?

@kunaltyagi In fact, this is my experience of using VTK to display Chinese, and I currently have no experience using PCL for display.

There are two points to note when displaying Chinese in VTK:

1. std::string needs to be converted to UTF8. I found this method from the Internet, and it works.If you don’t do this, VTK won’t display anything. I guess VTK parses the string in ASCLL mode, and the corresponding characters cannot be displayed.
2. The default font does not support Chinese, you need to set other fonts, I usually choose Microsoft Yahei(msyh.ttc), which is the font that comes with the system.If you don’t do this, even if UTF8 Chinese is displayed, it will be displayed as a question mark "?".

1.string_to_utf8, use this function for conversion

std::string string_to_utf8(const std::string& String)
{
	long nwLen = MultiByteToWideChar(CP_ACP, 0, String.c_str(), -1, NULL, 0);
	wchar_t* pwBuf = new wchar_t[nwLen + 1];
	ZeroMemory(pwBuf, nwLen * 2 + 2);
	MultiByteToWideChar(CP_ACP, 0, String.c_str(), String.length(), pwBuf, nwLen);
	long nLen = WideCharToMultiByte(CP_UTF8, 0, pwBuf, -1, NULL, NULL, NULL, NULL);
	char* pBuf = new char[nLen + 1];
	ZeroMemory(pBuf, nLen + 1);
	WideCharToMultiByte(CP_UTF8, 0, pwBuf, nwLen, pBuf, nLen, NULL, NULL);
	std::string retStr(pBuf);
	delete[] pwBuf;
	delete[] pBuf;
	pwBuf = nullptr;
	pBuf = nullptr;
	return retStr;
}

2.The code for displaying TextActor in vtk is for reference only, I don’t know what the corresponding display method is in PCL.

//Initialize window display 
vtkNew<vtkRenderWindow> Window;
vtkNew<vtkRenderer> Renderer;
Window->AddRenderer(Renderer);

//Add Chinese display
vtkNew<vtkTextActor> InformationTextActor;
InformationTextActor->SetInput(string_to_utf8(std::string("测试")).c_str());
InformationTextActor->SetPosition(5, 5);
InformationTextActor->GetTextProperty()->SetColor(1, 1, 1);
InformationTextActor->GetTextProperty()->SetFontFamily(VTK_FONT_FILE);
InformationTextActor->GetTextProperty()->SetFontFile("C:\\Windows\\Fonts\\msyh.ttc");
Renderer->AddActor(InformationTextActor);

//Add interaction and refresh window
vtkNew<vtkRenderWindowInteractor> RenderWindowInteractor ;
RenderWindowInteractor->SetRenderWindow(Window);
RenderWindowInteractor->Initialize();
RenderWindowInteractor->GetRenderWindow()->Render();
RenderWindowInteractor->Start();

[WangZP10969]

I referenced the method in the blog and modified addText3D. Currently, the white text can be displayed, but I have no idea how to modify the color.
[VTK] Display Chinese in the 3D scene of VTK 8.2

Modifications in pcl_visualizer.hpp:
line 678:

vtkSmartPointer<vtkVectorText> textSource = vtkSmartPointer<vtkVectorText>::New ();
textSource->SetText (text.c_str());
textSource->Update ();

vtkSmartPointer<vtkPolyDataMapper> textMapper = vtkSmartPointer<vtkPolyDataMapper>::New ();
textMapper->SetInputConnection (textSource->GetOutputPort ());

change into

vtkNew<vtkFreeTypeStringToImage> stringImage;
vtkNew<vtkTextProperty> textProperty;
vtkNew<vtkImageData> imageData;
vtkNew<vtkDataSetMapper> textMapper;
textProperty->SetFontFamily(VTK_FONT_FILE);
textProperty->SetFontFile("C:\\Windows\\Fonts\\msyh.ttc");
stringImage->RenderString(textProperty, vtkUnicodeString::from_utf8(text), 300, imageData);
textMapper->SetInputDataObject(imageData);

The test program code is as follows:

#include <pcl/visualization/pcl_visualizer.h>
#include <pcl/common/common_headers.h>

std::string string_to_utf8(const std::string& String)
{
	long nwLen = MultiByteToWideChar(0, 0, String.c_str(), -1, 0, 0);
	wchar_t* pwBuf = new wchar_t[nwLen + 1];
	memset(pwBuf, 0, nwLen * 2 + 2);
	MultiByteToWideChar(0, 0, String.c_str(), String.length(), pwBuf, nwLen);
	long nLen = WideCharToMultiByte(65001, 0, pwBuf, -1, 0, 0, 0, 0);
	char* pBuf = new char[nLen + 1];
	memset(pBuf, 0, nLen + 1);
	WideCharToMultiByte(65001, 0, pwBuf, nwLen, pBuf, nLen, 0, 0);
	std::string retStr(pBuf);
	delete[] pwBuf;
	delete[] pBuf;
	pwBuf = nullptr;
	pBuf = nullptr;
	return retStr;
}

int main(int argc, char* argv[])
{
	pcl::visualization::PCLVisualizer viewer("3D Viewer");
	viewer.setBackgroundColor(0, 0, 0);
	pcl::PointXYZ pointUTF8(1, 1, 1);
	viewer.addText3D(string_to_utf8("Test 测试"), pointUTF8, 0.01, 0, 1, 1, "sample text UTF8");
	viewer.addCoordinateSystem(1.0);
	viewer.initCameraParameters();
	while (!viewer.wasStopped())
	{
		viewer.spinOnce(100);
	}
}

The effect is as follows:

[jiaobinbin152]

I referenced the method in the blog and modified addText3D. Currently, the white text can be displayed, but I have no idea how to modify the color.
[VTK] Display Chinese in the 3D scene of VTK 8.2

Modifications in pcl_visualizer.hpp:
line 678:

vtkSmartPointer<vtkVectorText> textSource = vtkSmartPointer<vtkVectorText>::New ();
textSource->SetText (text.c_str());
textSource->Update ();

vtkSmartPointer<vtkPolyDataMapper> textMapper = vtkSmartPointer<vtkPolyDataMapper>::New ();
textMapper->SetInputConnection (textSource->GetOutputPort ());

change into

vtkNew<vtkFreeTypeStringToImage> stringImage;
vtkNew<vtkTextProperty> textProperty;
vtkNew<vtkImageData> imageData;
vtkNew<vtkDataSetMapper> textMapper;
textProperty->SetFontFamily(VTK_FONT_FILE);
textProperty->SetFontFile("C:\\Windows\\Fonts\\msyh.ttc");
stringImage->RenderString(textProperty, vtkUnicodeString::from_utf8(text), 300, imageData);
textMapper->SetInputDataObject(imageData);

The test program code is as follows:

#include <pcl/visualization/pcl_visualizer.h>
#include <pcl/common/common_headers.h>

std::string string_to_utf8(const std::string& String)
{
	long nwLen = MultiByteToWideChar(0, 0, String.c_str(), -1, 0, 0);
	wchar_t* pwBuf = new wchar_t[nwLen + 1];
	memset(pwBuf, 0, nwLen * 2 + 2);
	MultiByteToWideChar(0, 0, String.c_str(), String.length(), pwBuf, nwLen);
	long nLen = WideCharToMultiByte(65001, 0, pwBuf, -1, 0, 0, 0, 0);
	char* pBuf = new char[nLen + 1];
	memset(pBuf, 0, nLen + 1);
	WideCharToMultiByte(65001, 0, pwBuf, nwLen, pBuf, nLen, 0, 0);
	std::string retStr(pBuf);
	delete[] pwBuf;
	delete[] pBuf;
	pwBuf = nullptr;
	pBuf = nullptr;
	return retStr;
}

int main(int argc, char* argv[])
{
	pcl::visualization::PCLVisualizer viewer("3D Viewer");
	viewer.setBackgroundColor(0, 0, 0);
	pcl::PointXYZ pointUTF8(1, 1, 1);
	viewer.addText3D(string_to_utf8("Test 测试"), pointUTF8, 0.01, 0, 1, 1, "sample text UTF8");
	viewer.addCoordinateSystem(1.0);
	viewer.initCameraParameters();
	while (!viewer.wasStopped())
	{
		viewer.spinOnce(100);
	}
}

The effect is as follows:

Again Thanks WangZP10969 . This issue has sloved.
note: add #include <vtkImageData.h> in pcl_visualizer.hpp.