3d圣诞树动态c++语言编程代码

对于3D圣诞树动画的实现，在C++环境中通常会依赖于图形库的支持，比如OpenGL。下面提供一段基于OpenGL和GLUT库来创建简单3D圣诞树并赋予其基本动态效果的例子[^1]。

### 使用OpenGL绘制简单的3D圣诞树

#include <GL/glut.h>
#include <cmath>

void init() {
    glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // 设置背景颜色为黑色
}

// 绘制函数定义
void drawTree(float scale) {
    glColor3f(0.2f, 0.8f, 0.2f);
    
    glBegin(GL_TRIANGLES);
        glVertex3f(-scale * 0.5f, -scale * 0.5f, scale*0.5f);
        glVertex3f(scale * 0.5f, -scale * 0.5f, scale*0.5f);
        glVertex3f(0.0f, scale * 0.7f, scale*0.5f);

        glVertex3f(-scale * 0.4f, scale * 0.6f, scale*0.5f);
        glVertex3f(scale * 0.4f, scale * 0.6f, scale*0.5f);
        glVertex3f(0.0f, scale * 1.2f, scale*0.5f);
        
        glVertex3f(-scale * 0.3f, scale * 1.1f, scale*0.5f);
        glVertex3f(scale * 0.3f, scale * 1.1f, scale*0.5f);
        glVertex3f(0.0f, scale * 1.6f, scale*0.5f);
    glEnd();

    // 树干部分
    glColor3f(0.69f, 0.4f, 0.1f);
    glutSolidCube(scale / 2.f);
}

float angle = 0;

void display(void){
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    
    gluLookAt(
        sin(angle)*3, cos(angle), 2,
        0, 0, 0,
        0, 1, 0
    );

    glPushMatrix();
    glTranslatef(0, -0.5, 0);
    drawTree(sin(glutGet(GLUT_ELAPSED_TIME)/1000.0));
    glPopMatrix();

    glutSwapBuffers();  
    angle += 0.01;
}
 
int main(int argc, char **argv){
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
    glutCreateWindow("Simple 3D Christmas Tree");
    glEnable(GL_DEPTH_TEST);
    init();
    glutIdleFunc(display);
    glutDisplayFunc(display);
    glutMainLoop();
    return 0;
}

这段程序通过`glutTimerFunc()`实现了时间驱动下的旋转视角变化以及树木大小随时间波动的效果，从而模拟出了一个具有轻微摇晃感的小型三维圣诞树模型。