效果:

代码:

#include <iostream>
#include <pangolin/pangolin.h>

// pangolin 绘制文字demo

using namespace std;

int main() {

    //创建一个窗口
    pangolin::CreateWindowAndBind("PangolinShowText", 640, 480);

    // 定义字体
    pangolin::GlFont * text_font = new pangolin::GlFont("./DejaVuSans.ttf", 25.0);

    glEnable(GL_DEPTH_TEST);
    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    pangolin::OpenGlRenderState s_cam(
            pangolin::ProjectionMatrix(640, 480, 420, 420, 320, 320, 0.2, 100),
            pangolin::ModelViewLookAt(-2, 2, -2, 0, 0, 0, pangolin::AxisY)
    );

    pangolin::Handler3D handler(s_cam);
    pangolin::View & d_cam = pangolin::CreateDisplay()
            .SetBounds(0.0, 1.0, 0.0, 1.0)
            .SetHandler(&handler);

    string text = "Hello,Pangolin!";

    while( ! pangolin::ShouldQuit()){
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        d_cam.Activate(s_cam);

        
        // 在对应位置画字体
        glColor3f(1.0,0.0,0.0);
        text_font->Text(text.c_str()).Draw(3, 1, 1);

        // ---
        auto gltext_label_global_ = text_font->Text(text);

        auto cur_width = d_cam.v.w;
        auto cur_height = d_cam.v.h;

        GLint view[4];
        glGetIntegerv(GL_VIEWPORT, view);

        glMatrixMode(GL_PROJECTION);
        glPushMatrix();
        glLoadIdentity();
        glOrtho(0, cur_width, 0, cur_height, -1, 1);

        glMatrixMode(GL_MODELVIEW);
        glPushMatrix();
        glLoadIdentity();

        glTranslatef(5, gltext_label_global_.Height(), 1.);//
        glColor3ub(127, 127, 127);
        gltext_label_global_.Draw();

        // Restore modelview / project matrices
        glMatrixMode(GL_PROJECTION);
        glPopMatrix();
        glMatrixMode(GL_MODELVIEW);
        glPopMatrix();
        // ---
        
        pangolin::glDrawColouredCube();

        pangolin::FinishFrame();
    }

    return 0;
}

参考

博客
高博开源代码