使用OpenGL转换3D文本

#include <GL/glut.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include <ft2build.h>
#include FT_FREETYPE_H

FT_Library library;
FT_Face face;

void init() {
    glClearColor(0.0, 0.0, 0.0, 0.0);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(45.0, 1.0, 1.0, 30.0);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    gluLookAt(0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
}

void draw_text(const char* text, float x, float y, float z) {
    glColor3f(1.0, 1.0, 1.0);
    glRasterPos3f(x, y, z);
    for (int i = 0; text[i] != '\0'; i++) {
        glutBitmapCharacter(GLUT_BITMAP_HELVETICA_12, text[i]);
    }
}

void display() {
    glClear(GL_COLOR_BUFFER_BIT);
    glColor3f(1.0, 1.0, 1.0);
    draw_text("Hello, world!", 0.0, 0.0, 0.0);
    glFlush();
}

int main(int argc, char** argv) {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
    glutInitWindowSize(500, 500);
    glutInitWindowPosition(100, 100);
    glutCreateWindow("3D Text");
    init();
    glutDisplayFunc(display);
    glutMainLoop();
    return 0;
}