Question

我真的想画一个立方体，球在立方体的墙壁上弹跳，但我不能比下面的代码更进一步，这只是一个旋转的立方体新手，我刚开始学习上周的opengl，如果有人可以帮我提供所需的信息，我将非常感激，我希望球在没有相互接触的情况下反复颠倒，并且它的半径应该是相同的

#include <GL\glut.h>
 GLfloat xRotated, yRotated, zRotated;
void init(void)
{
glClearColor(0,0,0,0);

}

void DrawCube(void)
{

     glMatrixMode(GL_MODELVIEW);
    // clear the drawing buffer.
    glClear(GL_COLOR_BUFFER_BIT);
   glLoadIdentity();
        glTranslatef(0.0,0.0,-10.5);
    glRotatef(xRotated,1.0,0.0,0.0);
    // rotation about Y axis
    glRotatef(yRotated,0.0,1.0,0.0);
    // rotation about Z axis
    glRotatef(zRotated,0.0,0.0,1.0);
  glBegin(GL_QUADS);        // Draw The Cube Using quads
    glColor3f(0.0f,1.0f,0.0f);    // Color Blue
    glVertex3f( 1.0f, 1.0f,-1.0f);    // Top Right Of The Quad (Top)
    glVertex3f(-1.0f, 1.0f,-1.0f);    // Top Left Of The Quad (Top)
    glVertex3f(-1.0f, 1.0f, 1.0f);    // Bottom Left Of The Quad (Top)
    glVertex3f( 1.0f, 1.0f, 1.0f);    // Bottom Right Of The Quad (Top)
    glColor3f(1.0f,0.5f,0.0f);    // Color Orange
    glVertex3f( 1.0f,-1.0f, 1.0f);    // Top Right Of The Quad (Bottom)
    glVertex3f(-1.0f,-1.0f, 1.0f);    // Top Left Of The Quad (Bottom)
    glVertex3f(-1.0f,-1.0f,-1.0f);    // Bottom Left Of The Quad (Bottom)
    glVertex3f( 1.0f,-1.0f,-1.0f);    // Bottom Right Of The Quad (Bottom)
    glColor3f(1.0f,0.0f,0.0f);    // Color Red    
    glVertex3f( 1.0f, 1.0f, 1.0f);    // Top Right Of The Quad (Front)
    glVertex3f(-1.0f, 1.0f, 1.0f);    // Top Left Of The Quad (Front)
    glVertex3f(-1.0f,-1.0f, 1.0f);    // Bottom Left Of The Quad (Front)
    glVertex3f( 1.0f,-1.0f, 1.0f);    // Bottom Right Of The Quad (Front)
    glColor3f(1.0f,1.0f,0.0f);    // Color Yellow
    glVertex3f( 1.0f,-1.0f,-1.0f);    // Top Right Of The Quad (Back)
    glVertex3f(-1.0f,-1.0f,-1.0f);    // Top Left Of The Quad (Back)
    glVertex3f(-1.0f, 1.0f,-1.0f);    // Bottom Left Of The Quad (Back)
    glVertex3f( 1.0f, 1.0f,-1.0f);    // Bottom Right Of The Quad (Back)
    glColor3f(0.0f,0.0f,1.0f);    // Color Blue
    glVertex3f(-1.0f, 1.0f, 1.0f);    // Top Right Of The Quad (Left)
    glVertex3f(-1.0f, 1.0f,-1.0f);    // Top Left Of The Quad (Left)
    glVertex3f(-1.0f,-1.0f,-1.0f);    // Bottom Left Of The Quad (Left)
    glVertex3f(-1.0f,-1.0f, 1.0f);    // Bottom Right Of The Quad (Left)
    glColor3f(1.0f,0.0f,1.0f);    // Color Violet
    glVertex3f( 1.0f, 1.0f,-1.0f);    // Top Right Of The Quad (Right)
    glVertex3f( 1.0f, 1.0f, 1.0f);    // Top Left Of The Quad (Right)
    glVertex3f( 1.0f,-1.0f, 1.0f);    // Bottom Left Of The Quad (Right)
    glVertex3f( 1.0f,-1.0f,-1.0f);    // Bottom Right Of The Quad (Right)
  glEnd();            // End Drawing The Cube
glFlush();
}

void animation(void)
{

     yRotated += 0.01;
     xRotated += 0.02;
    DrawCube();
}

void reshape(int x, int y)
{
    if (y == 0 || x == 0) return;  //Nothing is visible then, so return
    //Set a new projection matrix
    glMatrixMode(GL_PROJECTION);  
    glLoadIdentity();
    //Angle of view:40 degrees
    //Near clipping plane distance: 0.5
    //Far clipping plane distance: 20.0

    gluPerspective(40.0,(GLdouble)x/(GLdouble)y,0.5,20.0);
    glMatrixMode(GL_MODELVIEW);
    glViewport(0,0,x,y);  //Use the whole window for rendering
}

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

glutInit(&argc, argv);
//we initizlilze the glut. functions
glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);
glutInitWindowPosition(100, 100);
glutCreateWindow(argv[0]);
init();
glutDisplayFunc(DrawCube);
glutReshapeFunc(reshape);
//Set the function for the animation.
glutIdleFunc(animation);
glutMainLoop();
return 0;
}

Answer 1

引入一个球对象或至少一个球的位置向量。
让绘图坐标取决于球的位置;既然你有一个立方体，你现在需要找到一个球的绘图代码，你不是第一个这样做的，所以在互联网上可以找到很多例子。
现在，您可以更改动画功能，将球移向您想要的方向;一个简单的实现是让它向下，当它到达底部时，你切换一个布尔值，表示它上升，然后当它是一个顶部你再次切换它。

在伪代码中我们有这样的东西：
```
if (goingDown)
{
    letBallGoDown();

    if (ballTouchesBottom())
    {
        goingDown = false;
    }
}
else
{
    letBallGoUp();

    if (ballTouchesTop())
    {
        goingDown = true;
    }
}
```
确保在检查是否触及顶部或底部时考虑半径。

用它内部的弹跳球创建一个立方体

1 个答案: