Question

我正在尝试在窗口中绘制云，并将它们设置为相机。我遇到的问题是我想连续不断地重新绘制。有人能告诉我我在这里缺少什么吗？

以下是代码：

#include <gl/glut.h>

int width = 800, height = 600;
float theta = 0, distance1 = -600, distance2 = -600;
void drawCloud()
{
glPushMatrix();
glTranslated(1,0,-2);
glutSolidSphere(4,10,10);
glTranslated(-2,0,-5);
glutSolidSphere(4,10,10);
glTranslated(-1,0,3);
glutSolidSphere(4,10,10);
glPopMatrix();

}

void drawCloudFormation()
{
glPushMatrix();
glTranslated(-60,30,-300);
drawCloud();
glPopMatrix();

glPushMatrix();
glTranslated(15,3,-150);
drawCloud();
glPopMatrix();

glPushMatrix();
glTranslated(50,30,-200);
drawCloud();
glPopMatrix();

glPushMatrix();
glTranslated(-15,-15,-250);
drawCloud();
glPopMatrix();

glPushMatrix();
glTranslated(25,-25,-100);
drawCloud();
glPopMatrix();

glPushMatrix();
glTranslated(-30,0,-50);
drawCloud();
glPopMatrix();
}

void display()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
//glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);

glPushMatrix();
glTranslated(0,0,distance1);
drawCloudFormation();
glPopMatrix();

glPushMatrix();
glTranslated(0,0,distance1-200);
glScaled(-1,1,1);
drawCloudFormation();
glPopMatrix();

glPushMatrix();
glTranslated(0,0,distance2-400);
glScaled(1,1,-1);
drawCloudFormation();
glPopMatrix();

glPushMatrix();
glTranslated(0,0,distance2-600);
glScaled(-1,1,1);
glScaled(1,1,-1);
drawCloudFormation();
glPopMatrix();

glutSwapBuffers();
}

void idle()
{
theta += 0.2;
if (theta == 360) theta = 360;

distance1 += 1;
if (distance1 > 200) distance1 = -600;

distance2 += 1;
if (distance2 > 600) distance2 = -600;

glutPostRedisplay();
}

void main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
glutInitWindowSize(width, height);
glutInitWindowPosition(100, 200);
glutCreateWindow("Space Ship");
glClearColor(0, 0, 1, 1);


glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(120, 1, 0.1, 600);
//glOrtho(-2, 2, -2, 2, 0.1, 200);

glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
//gluLookAt(0, 0, -200, 0, 0, -600, 0, 1, 0);

glutDisplayFunc(display);
glutIdleFunc(idle);

glutMainLoop();
}

Answer 1

查看particle systems。

你基本上希望场景远端的矩形发射器以相对于摄像机固定的速度喷出云（粒子）。当云在摄像机后面移动时将它们标记为非活动状态，粒子系统将在发射器处产生新的云。

3D滚动场景 - OpenGL

1 个答案: