opengl - make 3D Cube 製作立方體

實作用空間中六個正方形做出正立方體

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程式碼:

#include "GL\glut.h"
#include <windows.h>
#include <iostream>

GLdouble camera_fovy = 20.0f; //視野廣角的角度
//GLdouble camera_aspect = 1; //投影布幕的 width/height比例
GLdouble camera_near = 0.01f; //最近可以看到的距離
GLdouble camera_far = 100.0f; //最遠可以看到的距離

void drawCube() //畫正立方體
{
 //開始畫圖
 glBegin(GL_QUADS); //畫四邊形
 glColor3f(1, 0, 0); glVertex3f(0, 0, 0);
 glColor3f(1, 0, 0); glVertex3f(0, 1, 0);
 glColor3f(1, 0, 0); glVertex3f(1, 1, 0);
 glColor3f(1, 0, 0); glVertex3f(1, 0, 0);
 glEnd();
 //結束畫圖

 //開始畫圖
 glBegin(GL_QUADS); //畫四邊形
 glColor3f(1, 0, 0); glVertex3f(0, 0, 1);
 glColor3f(1, 0, 0); glVertex3f(0, 1, 1);
 glColor3f(1, 0, 0); glVertex3f(1, 1, 1);
 glColor3f(1, 0, 0); glVertex3f(1, 0, 1);
 glEnd();
 //結束畫圖

 //開始畫圖
 glBegin(GL_QUADS); //畫四邊形
 glColor3f(0, 1, 0); glVertex3f(0, 0, 0);
 glColor3f(0, 1, 0); glVertex3f(0, 0, 1);
 glColor3f(0, 1, 0); glVertex3f(1, 0, 1);
 glColor3f(0, 1, 0); glVertex3f(1, 0, 0);
 glEnd();
 //結束畫圖

 //開始畫圖
 glBegin(GL_QUADS);  //畫四邊形
 glColor3f(0, 1, 0); glVertex3f(0, 1, 0);
 glColor3f(0, 1, 0); glVertex3f(0, 1, 1);
 glColor3f(0, 1, 0); glVertex3f(1, 1, 1);
 glColor3f(0, 1, 0); glVertex3f(1, 1, 0);
 glEnd();
 //結束畫圖

 //開始畫圖
 glBegin(GL_POLYGON); //畫多邊形
 glColor3f(0, 0, 1); glVertex3f(0, 0, 0);
 glColor3f(0, 0, 1); glVertex3f(0, 0, 1);
 glColor3f(0, 0, 1); glVertex3f(0, 1, 1);
 glColor3f(0, 0, 1); glVertex3f(0, 1, 0);
 glEnd();
 //結束畫圖

 //開始畫圖
 glBegin(GL_POLYGON);  //畫四邊形
 glColor3f(0, 0, 1); glVertex3f(1, 0, 0);
 glColor3f(0, 0, 1); glVertex3f(1, 0, 1);
 glColor3f(0, 0, 1); glVertex3f(1, 1, 1);
 glColor3f(0, 0, 1); glVertex3f(1, 1, 0);
 glEnd();
 //結束畫圖
}

void reshape(GLsizei width, GLsizei height) { 

 if (height == 0) height = 1;                // 防止height為0
 GLfloat aspect = (GLfloat)width / (GLfloat)height; //確保圖片不會被延展

 glViewport(0, 0, width, height); //重繪窗口

 glMatrixMode(GL_PROJECTION);  // 投影視野
 glLoadIdentity();             // 設置乘投影視野
 gluPerspective(camera_fovy, aspect, camera_near, camera_far); //乘上投影矩陣

 gluLookAt(
 5, 10, 10,  //攝影機座標
 0, 0, 0,  //要看的座標
 0, 1, 0); //攝影機頭頂的向量
}


void render()
{

 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // 清出BUFFER
 
 glMatrixMode(GL_MODELVIEW);     //模型視野
 glLoadIdentity();               //設置成模型視野

 drawCube(); //畫出正立方體

 glutSwapBuffers(); //把畫好的東西刷上去

}

void initGL()
{
 glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // 清空顏色
 glClearDepth(1.0f);                   // 清空深度
 glEnable(GL_DEPTH_TEST);   // 打開"根據座標的遠近自動隱藏被遮住的圖形"
 glDepthFunc(GL_LEQUAL);    // 深度緩衝比較函數設為"輸入的深度值小於或等於參考值"則通過
 glShadeModel(GL_SMOOTH);   // 設定著色模式為"使用頂點渲染"
 glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);  // 指定顏色和紋理的差值質量 -> 最高質量
}

int main(int argc, char** argv)
{

 glutInit(&argc, argv);//初始化glut

 glutInitDisplayMode(GLUT_DOUBLE); //初始化顯示器
 glutInitWindowPosition(100, 100); //初始化視窗左上角的位置
 glutInitWindowSize(600, 600); //初始化視窗大小
 glutCreateWindow("DING"); //視窗名稱

 glutIdleFunc(render); //設置全局的回調函數 

 glutDisplayFunc(render); //顯示器
 glutReshapeFunc(reshape); //呈現

 initGL(); //初始畫面

 glutMainLoop();
 return 0;
}

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運行結果: