第2关:OpenGL球体镜面反射
一.任务描述
根据提示,在右侧修改代码,并自己绘制出图形。平台会对你编写的代码进行测试。
1.本关任务
为在场景中增加光照,需要执行以下步骤。 (1).设置一个或多个光源,设定它的有关属性; (2).选择一种光照模型; (3).设置物体的材料属性。
2.预期输出
3.具体要求
给球体添加环境光,漫反射和镜面反射等效果,每个参数的含义已在代码中给出。 (1).左侧圆球有环境光、漫反射和镜面低反射; (2).中间圆球有环境光、漫反射和镜面高反射; (3).右侧圆球有彩色环境光、漫反射、镜面高反射和材料辐射。
二.相关知识
为了完成本关任务,你需要掌握:了解掌握OpenGL程序的光照与材质,能正确使用光源与材质函数设置所需的绘制效果。
开始你的任务吧,祝你成功!
三.实验代码
// 提示:在合适的地方修改或添加代码
#include <GL/freeglut.h>
#include<stdlib.h>
// 评测代码所用头文件-开始
#include<opencv2/core/core.hpp>
#include<opencv2/highgui/highgui.hpp>
#include<opencv2/imgproc/imgproc.hpp>
using namespace std;
// 评测代码所用头文件-结束
void init(void)
{
GLfloat position[] = {0.0,3.0,2.0,0.0};
GLfloat ambient[]={0.0,0.0,0.0,1.0};
GLfloat diffuse[]={1.0,1.0,1.0,1.0};
GLfloat specular[]={1.0,1.0,1.0,1.0};
GLfloat lmodel_ambient[]={0.4,0.4,0.4,1.0};
GLfloat local_view[]={0.0};
glClearColor(0.0, 0.1, 0.1,0.0);
glShadeModel(GL_SMOOTH);
glLightfv(GL_LIGHT0,GL_AMBIENT,ambient);
glLightfv(GL_LIGHT0,GL_DIFFUSE,diffuse);
glLightfv(GL_LIGHT0,GL_POSITION,position);
glLightModelfv(GL_LIGHT_MODEL_AMBIENT,lmodel_ambient);
glLightModelfv(GL_LIGHT_MODEL_LOCAL_VIEWER,local_view);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_DEPTH_TEST);
}
void display(void)
{
GLfloat no_mat[]={0.0,0.0,0.0,1.0}; //没有光
GLfloat mat_ambient[]={0.7,0.7,0.7,1.0}; //环境光
GLfloat mat_ambient_color[]={0.8, 0.8, 0.2, 1.0}; //彩色环境光
GLfloat mat_diffuse[]={0.1,0.5,0.8,1.0}; //漫反射
GLfloat mat_specular[]={1.0,1.0,1.0,1.0}; //镜面反射
GLfloat no_shininess[] = {0.0}; //没有镜面反射
GLfloat low_shininess[]={5.0}; //低镜面反射
GLfloat high_shininess[]={100.0}; //高镜面反射
GLfloat mat_emission[]={0.3,0.2,0.2,0.0}; //材料辐射光颜色
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glPushMatrix();
glTranslatef(-3.0, 0.0, 0.0);
// 请在此添加你的代码,左侧圆球有环境光、漫反射镜面低反射
/********** Begin ********/
//材质的环境颜色,params默认值(0.2,0.2,0.2,1.0)
glMaterialfv(GL_FRONT,GL_AMBIENT,mat_ambient);//环境光
//材质的散射颜色,params默认值(0.8,0.8,0.8,1.0)
glMaterialfv(GL_FRONT,GL_DIFFUSE, mat_diffuse);//漫反射
//材质的镜面反射颜色,params默认值(0.0,0.0,0.0,1.0)
glMaterialfv(GL_FRONT,GL_SPECULAR,mat_specular);//镜面反射
//镜面反射指数,params默认值0.0
glMaterialfv(GL_FRONT,GL_SHININESS,low_shininess); //低镜面反射
//材质的发射光颜色,params默认值(0.0,0.0,0.1,1.0)
glMaterialfv(GL_FRONT,GL_EMISSION,no_mat);//无材料辐射光颜色
/********** End *********/
glutSolidSphere(1.0, 50, 50);
glPopMatrix();
glPushMatrix();
// 请在此添加你的代码,中间圆球有环境光、漫反射镜面高反射
/********** Begin ********/
//材质的环境颜色,params默认值(0.2,0.2,0.2,1.0)
glMaterialfv(GL_FRONT,GL_AMBIENT,mat_ambient);//环境光
//材质的散射颜色,params默认值(0.8,0.8,0.8,1.0)
glMaterialfv(GL_FRONT,GL_DIFFUSE, mat_diffuse);//漫反射
//材质的镜面反射颜色,params默认值(0.0,0.0,0.0,1.0)
glMaterialfv(GL_FRONT,GL_SPECULAR,mat_specular);//镜面反射
//镜面反射指数,params默认值0.0
glMaterialfv(GL_FRONT,GL_SHININESS,high_shininess);//高镜面反射
//材质的发射光颜色,params默认值(0.0,0.0,0.1,1.0)
glMaterialfv(GL_FRONT,GL_EMISSION,no_mat);//无材料辐射光颜色
/********** End *********/
glutSolidSphere(1.0, 50, 50);
glPopMatrix();
glPushMatrix();
glTranslatef(3.0, 0.0, 0.0);
// 请在此添加你的代码,右侧圆球有彩色环境光、漫反射、镜面高反射和材料辐射
/********** Begin ********/
//材质的环境颜色,params默认值(0.2,0.2,0.2,1.0)
glMaterialfv(GL_FRONT,GL_AMBIENT,mat_ambient_color);//彩色环境光
//材质的散射颜色,params默认值(0.8,0.8,0.8,1.0)
glMaterialfv(GL_FRONT,GL_DIFFUSE, mat_diffuse);//漫反射
//材质的镜面反射颜色,params默认值(0.0,0.0,0.0,1.0)
glMaterialfv(GL_FRONT,GL_SPECULAR,mat_specular);//镜面反射
//镜面反射指数,params默认值0.0
glMaterialfv(GL_FRONT,GL_SHININESS,high_shininess);//高镜面反射
//材质的发射光颜色,params默认值(0.0,0.0,0.1,1.0)
glMaterialfv(GL_FRONT,GL_EMISSION,mat_emission);//材料辐射光颜色
/********** End *********/
glutSolidSphere(1.0, 50, 50);
glPopMatrix();
glFlush();
glutPostRedisplay();
}
void reshape(int w, int h)
{
glViewport(0, 0, (GLsizei)w, (GLsizei)h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(60.0, (GLfloat)w / (GLfloat)h, 1.0, 20.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(0.0, 5.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitWindowPosition(100, 100);
glutInitWindowSize(800, 600);
glutCreateWindow("几何变换示例");
init();
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutMainLoopEvent();
/*************以下为评测代码,与本次实验内容无关,请勿修改**************/
GLubyte* pPixelData = (GLubyte*)malloc(800 * 600 * 3);//分配内存
GLint viewport[4] = {0};
glReadBuffer(GL_FRONT);
glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
glGetIntegerv(GL_VIEWPORT, viewport);
glReadPixels(viewport[0], viewport[1], viewport[2], viewport[3], GL_RGB, GL_UNSIGNED_BYTE, pPixelData);
cv::Mat img;
std::vector<cv::Mat> imgPlanes;
img.create(600, 800, CV_8UC3);
cv::split(img, imgPlanes);
for (int i = 0; i < 600; i++) {
unsigned char* plane0Ptr = imgPlanes[0].ptr<unsigned char>(i);
unsigned char* plane1Ptr = imgPlanes[1].ptr<unsigned char>(i);
unsigned char* plane2Ptr = imgPlanes[2].ptr<unsigned char>(i);
for (int j = 0; j < 800; j++) {
int k = 3 * (i * 800 + j);
plane2Ptr[j] = pPixelData[k];
plane1Ptr[j] = pPixelData[k + 1];
plane0Ptr[j] = pPixelData[k + 2];
}
}
cv::merge(imgPlanes, img);
cv::flip(img, img, 0);
cv::namedWindow("openglGrab");
cv::imshow("openglGrab", img);
//cv::waitKey();
cv::imwrite("../img_step1/test.jpg", img);
return 0;
}