现在来生成球光照贴图。
上一文的方法对于粗糙的物体是合适的，这个球上有镜面反射产生亮斑。
所以、这里准备以贴图坐标所对应球上点和视点连线为入射光，生成密集的球光照贴图。
双向生成密集球光照图
//以球上的点和视点为入射光，反面使用对称视点(双向)
void 球纹理生成球上点和视点为入射光(vector<Sphere_GLSL> &spheres, std::vector<Triangle_GLSL> &triangles, int Sphere_n) {double* image = new double[WIDTH * HEIGHT * 4];memset(image, 0.0, sizeof(double) * WIDTH * HEIGHT * 4);Sphere_GLSL *s1 = NULL;for (int i = 0; i < spheres.size(); i++){if (spheres[i].Sphere_n == Sphere_n) {s1 = &spheres[i];break;}}MaxMin t0 = 计算MaxMin(spheres, Sphere_n);float zmax, zmin;zmin = t0.zmin;zmax = t0.zmax; printf("zmin:%.2f\n", zmin);printf("zmax:%.2f\n", zmax);//反面视点vec3 eye = EYE; eye.z = -.9;// zmin - .2f;printf("eye.z:%.2f\n", eye.z);// 球体的基本参数float x0 = s1->O.x, y0 = s1->O.y, z0 = s1->O.z; // 球心坐标float r = s1->R; // 球的半径std::vector<Ray> Raywh;for (int k = 0; k < SAMPLE; k++){if (k % 10 == 0)printf("\r%d", k);double* p = image;Raywh.clear();//生成入射光组-------------------------------------开始结束for (float u = 0; u < WIDTH; u++){for (float w = 0; w < HEIGHT; w++){float x, y, z; // 计算球体表面上的点坐标求xyz(x0, y0, z0, r, u, w, x, y, z);// MSAAif (k != SAMPLE - 1) {x += (randf() - 0.5f) / float(WIDTH);y += (randf() - 0.5f) / float(HEIGHT);}//以球上的点和视点为入射光vec3 direction;Ray ray;// 计算光线投射方向if (z>=s1->O.z){//正面direction = normalize(vec3(x, y, z) - EYE);ray.startPoint = EYE;ray.direction = direction;Raywh.push_back(ray);}else {//反面direction = normalize(vec3(x, y, z) - eye);ray.startPoint = eye;ray.direction = direction;Raywh.push_back(ray);}}}//生成入射光组-------------------------------------结束std::vector<vec4> color;// 路径追踪pathTracing_GLSL_TSn(Raywh, color);int nc = 0;for (int i = 0; i < HEIGHT; i++){for (int j = 0; j < WIDTH; j++){//复制颜色vec4 color0 = color[nc++];color0 *= BRIGHTNESS;*p += color0.x; p++; // R 通道*p += color0.y; p++; // G 通道*p += color0.z; p++; // B 通道*p += color0.w; p++; // A 通道}}}printf("\n");//像素剪裁0-255powClamp0255(image, WIDTH*HEIGHT * 4);//保存图像char filename[256];sprintf_s(filename, "Sphere%d.png", Sphere_n);imSave(image, WIDTH, HEIGHT, filename);}
球1、2、3图:
然后运行opengl程序:
已经完成，后续应该把它制成OBJ,PLY文件，方便交流。
感谢观看!
)
