使用 C++ 在 OpenGL 中使用键盘移动 3d 形状
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【中文标题】使用 C++ 在 OpenGL 中使用键盘移动 3d 形状【英文标题】：Moving 3d shapes with keyboard in OpenGL with C++ 【发布时间】：2020-06-10 17:36:52 【问题描述】：我正在尝试使用箭头和向上翻页、向下翻页键将金字塔和立方体“分别”移动到前后、上下和左右，但我还做不到，没有一个拖曳形状正在移动我的两个问题是：我如何选择我想要移动的这些形状之一，为什么它们都没有移动？ 谢谢。
#include <GL/glut.h>
float xmove = 0, ymove = 0, zmove = 0;
float degree = 0;
float xscale = 1, yscale = 1, zscale = 1;
void right(void)
glLoadIdentity();//koordinat sistemimizetkilenmesin
xmove += 0.1;
void left(void)
glLoadIdentity();
xmove -= 0.1;
void up(void)
glLoadIdentity();
ymove += 0.1;
void down(void)
glLoadIdentity();
ymove -= 0.1;
void front(void)
glLoadIdentity();
zmove -= 0.1;
void back(void)
glLoadIdentity();
zmove += 0.1;
void keyboard(int button, int x, int y)
switch (button)
case GLUT_KEY_LEFT:left(); break;
case GLUT_KEY_RIGHT:right(); break;
case GLUT_KEY_UP:up(); break;
case GLUT_KEY_DOWN:down(); break;
case GLUT_KEY_PAGE_UP:front(); break;
case GLUT_KEY_PAGE_DOWN:back(); break;
glutPostRedisplay();
void Settings()
glClearColor(1,1,1,0);
glClearDepth(1.0f);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glShadeModel(GL_SMOOTH);
glHint(GL_PERSPECTIVE_CORRECTION_HINT , GL_NICEST);
void polygons(void)
glColor3f(1.0, 0.0, 0.0);
glRotatef(degree, 0.0, 1.0, 0.0);
glScalef(xscale, yscale, zscale);
glTranslatef(1.5, 0.0, -8.0);
glBegin(GL_TRIANGLES);//pyramid
// fronat face
glColor3f(1.0f, 0.0f, 0.0f); //red
glVertex3f(0.0f, 1.0f, 0.0f);
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(-1.0f, -1.0f, 1.0f);
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(1.0f, -1.0f, 1.0f);
// down face
glColor3f(1.0f, 0.0f, 0.0f); //red
glVertex3f(0.0f, 1.0f, 0.0f);
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(1.0f, -1.0f, 1.0f);
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(1.0f, -1.0f, -1.0f);
//back
glColor3f(1.0f, 0.0f, 0.0f); //red
glVertex3f(0.0f, 1.0f, 0.0f);
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(1.0f, -1.0f, -1.0f);
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(-1.0f, -1.0f, -1.0f);
//left
glColor3f(1.0f, 0.0f, 0.0f); //reed
glVertex3f(0.0f, 1.0f, 0.0f);
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(-1.0f, -1.0f, -1.0f);
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(-1.0f, -1.0f, 1.0f);
glEnd();
glLoadIdentity();
glTranslatef(-1.5, 0.0, -8.0);
glBegin(GL_QUADS); //cubic
glColor3f(1.0f, 0.0f, 1.0f); //pink
glVertex3f(1.0f, 1.0f, -1.0f);
glVertex3f(-1.0f, 1.0f, -1.0f);
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(1.0f, 1.0f, 1.0f);
//down face
glColor3f(1.0f, 0.5f, 0.0f); //orange
glVertex3f(1.0f, -1.0f, 1.0f);
glVertex3f(-1.0f, -1.0f, 1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(1.0f, -1.0f, -1.0f);
//front face
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, -1.0f, 1.0f);
glVertex3f(1.0f, -1.0f, 1.0f);
//back
glColor3f(1.0f, 1.0f, 0.0f); //yellow
glVertex3f(1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, 1.0f, -1.0f);
glVertex3f(1.0f, 1.0f, -1.0f);
//left
glColor3f(1.0f, 0.0f, 0.0f); //red
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, 1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, 1.0f);
//right
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(1.0f, 1.0f, -1.0f);
glVertex3f(1.0f, 1.0f, 1.0f);
glVertex3f(1.0f, -1.0f, 1.0f);
glVertex3f(1.0f, -1.0f, -1.0f);
glEnd();
void DrawingFunction()//painting
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
gluLookAt(0.0, 0.0, 2.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
polygons();
glutSwapBuffers();
void AppearanceAdjustment(int x, int y)
int aspect = x / y;
glViewport(0, 0, x, y);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45,aspect,0.1,20);
int main(int argc, char** argv)
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE);
glutInitWindowPosition(50, 50);
glutInitWindowSize(800, 600);
glutCreateWindow("3d shapes");
glutDisplayFunc(DrawingFunction);
glutReshapeFunc(AppearanceAdjustment);
glutSpecialFunc(keyboard);
Settings();
glutMainLoop();
return 0;
【问题讨论】：
【参考方案1】：glLoadIdentity() 必须在DrawingFunction 中调用：
void DrawingFunction()//painting
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity(); // <----
gluLookAt(0.0, 0.0, 2.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
polygons();
glutSwapBuffers();
添加一个偏移量数组和一个对象编号：
int object = 0;
float xmove[] 0, 0 ;
float ymove[] 0, 0 ;
float zmove[] 0, 0 ;
添加对象选择按钮并更改所选对象的偏移量。
glutPostRedisplay()必须在switch语句之后执行：
void keyboard(int button, int x, int y)
switch (button)
case GLUT_KEY_F1: object = 0; break;
case GLUT_KEY_F2: object = 1; break;
case GLUT_KEY_LEFT: xmove[object] -= 0.1; break;
case GLUT_KEY_RIGHT: xmove[object] += 0.1; break;
case GLUT_KEY_DOWN: ymove[object] -= 0.1; break;
case GLUT_KEY_UP: ymove[object] += 0.1; break;
case GLUT_KEY_PAGE_UP: zmove[object] -= 0.1; break;
case GLUT_KEY_PAGE_DOWN: zmove[object] += 0.1; break;
glutPostRedisplay();
您必须通过glTranslatef(xmove[i], ymove[i], zmove[i]) 翻译objects 对象。我推荐使用glPushMatrix/glPopMatrix:
void polygons(void)
glPushMatrix();
glColor3f(1.0, 0.0, 0.0);
glRotatef(degree, 0.0, 1.0, 0.0);
glScalef(xscale, yscale, zscale);
glTranslatef(1.5, 0.0, -8.0);
glTranslatef(xmove[0], ymove[0], zmove[0]); // <--- translate pyramid
// draw pyramid
glBegin(GL_TRIANGLES);//pyramid
// [...]
glEnd();
glTranslatef(-1.5, 0.0, -8.0);
glTranslatef(xmove[1], ymove[1], zmove[1]); // <--- translate cube
glBegin(GL_QUADS); //cubic
// [...]
glEnd();
glPopMatrix();
示例代码：
int object = 0;
float xmove[] 0, 0 ;
float ymove[] 0, 0 ;
float zmove[] 0, 0 ;
float degree = 0;
float xscale = 1, yscale = 1, zscale = 1;
void keyboard(int button, int x, int y)
switch (button)
case GLUT_KEY_F1: object = 0; break;
case GLUT_KEY_F2: object = 1; break;
case GLUT_KEY_LEFT: xmove[object] -= 0.1; break;
case GLUT_KEY_RIGHT: xmove[object] += 0.1; break;
case GLUT_KEY_DOWN: ymove[object] -= 0.1; break;
case GLUT_KEY_UP: ymove[object] += 0.1; break;
case GLUT_KEY_PAGE_UP: zmove[object] -= 0.1; break;
case GLUT_KEY_PAGE_DOWN: zmove[object] += 0.1; break;
glutPostRedisplay();
void Settings()
glClearColor(1,1,1,0);
glClearDepth(1.0f);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glShadeModel(GL_SMOOTH);
glHint(GL_PERSPECTIVE_CORRECTION_HINT , GL_NICEST);
void polygons(void)
glPushMatrix();
glColor3f(1.0, 0.0, 0.0);
glRotatef(degree, 0.0, 1.0, 0.0);
glScalef(xscale, yscale, zscale);
glTranslatef(1.5, 0.0, -8.0);
glTranslatef(xmove[0], ymove[0], zmove[0]); // <--- translate pyramid
glBegin(GL_TRIANGLES);//pyramid
// fronat face
glColor3f(1.0f, 0.0f, 0.0f); //red
glVertex3f(0.0f, 1.0f, 0.0f);
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(-1.0f, -1.0f, 1.0f);
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(1.0f, -1.0f, 1.0f);
// down face
glColor3f(1.0f, 0.0f, 0.0f); //red
glVertex3f(0.0f, 1.0f, 0.0f);
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(1.0f, -1.0f, 1.0f);
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(1.0f, -1.0f, -1.0f);
//back
glColor3f(1.0f, 0.0f, 0.0f); //red
glVertex3f(0.0f, 1.0f, 0.0f);
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(1.0f, -1.0f, -1.0f);
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(-1.0f, -1.0f, -1.0f);
//left
glColor3f(1.0f, 0.0f, 0.0f); //reed
glVertex3f(0.0f, 1.0f, 0.0f);
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(-1.0f, -1.0f, -1.0f);
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(-1.0f, -1.0f, 1.0f);
glEnd();
glPopMatrix();
glPushMatrix();
glTranslatef(-1.5, 0.0, -8.0);
glTranslatef(xmove[1], ymove[1], zmove[1]); // <--- translate cube
glBegin(GL_QUADS); //cubic
glColor3f(1.0f, 0.0f, 1.0f); //pink
glVertex3f(1.0f, 1.0f, -1.0f);
glVertex3f(-1.0f, 1.0f, -1.0f);
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(1.0f, 1.0f, 1.0f);
//down face
glColor3f(1.0f, 0.5f, 0.0f); //orange
glVertex3f(1.0f, -1.0f, 1.0f);
glVertex3f(-1.0f, -1.0f, 1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(1.0f, -1.0f, -1.0f);
//front face
glColor3f(0.0f, 0.0f, 1.0f); //blue
glVertex3f(1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, -1.0f, 1.0f);
glVertex3f(1.0f, -1.0f, 1.0f);
//back
glColor3f(1.0f, 1.0f, 0.0f); //yellow
glVertex3f(1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, 1.0f, -1.0f);
glVertex3f(1.0f, 1.0f, -1.0f);
//left
glColor3f(1.0f, 0.0f, 0.0f); //red
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, 1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, 1.0f);
//right
glColor3f(0.0f, 1.0f, 0.0f); //green
glVertex3f(1.0f, 1.0f, -1.0f);
glVertex3f(1.0f, 1.0f, 1.0f);
glVertex3f(1.0f, -1.0f, 1.0f);
glVertex3f(1.0f, -1.0f, -1.0f);
glEnd();
glPopMatrix();
void DrawingFunction()//painting
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(0.0, 0.0, 2.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
polygons();
glutSwapBuffers();
void AppearanceAdjustment(int x, int y)
int aspect = x / y;
glViewport(0, 0, x, y);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45,aspect,0.1,20);
int main(int argc, char** argv)
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE);
glutInitWindowPosition(50, 50);
glutInitWindowSize(800, 600);
glutCreateWindow("3d shapes");
glutDisplayFunc(DrawingFunction);
glutReshapeFunc(AppearanceAdjustment);
glutSpecialFunc(keyboard);
Settings();
glutMainLoop();
return 0;
【讨论】：
对不起，非常感谢先生【参考方案2】：您需要使用按键来选择类似于触发向上、向下、向左、向右...等功能的形状之一。假设按 a 为第一个形状，然后设置全局 int ishape= 1 或 ishape=2 如果 b 被按下。然后 draw 函数将检查 ishape 的值以查看它应该移动哪个形状。但实际上，每个形状都需要一个移动向量，否则它们的位移会混淆。然后你需要对需要使用移动向量进行位移的形状应用 gltranslate。
【讨论】：
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