bool alex::ObjectBase::refract(const Ray &inRay, const cv::Vec3d &intersection, const cv::Vec3d &normalVecN,
cv::Vec3d &color, Ray &outRay) const {
double cosI = inRay.getDirectionN().dot(normalVecN);
double sinI = sqrt(1 - cosI * cosI);
double sinR = sinI / refractive;
// 全反射
if (sinR > 1)
return false;
if (cosI == 0) {
// 不发生折射, 直线投射
outRay = Ray(intersection - normalVecN * alex::Epsilon, -normalVecN);
}
else {
// 计算垂直于法线, 与入射光,法线在同一平面, 与入射光成锐角的单位向量horizontalN
auto horizontalN = cv::normalize((inRay.getDirectionN() / cosI - normalVecN));
double r = asin(sinR);
auto refractDirection =
(normalVecN * (-cos(r)) + (horizontalN) * sinR);
outRay = Ray(intersection - normalVecN * alex::Epsilon, refractDirection);
}
color = refractColor;
return true;
}
bool alex::ObjectBase::brdf(const Ray &inRay, const cv::Vec3d &intersection, const cv::Vec3d &normalVecN,
cv::Vec3d &color, Ray &outRay) const {
outRay = Ray(intersection + normalVecN * alex::Epsilon, randomChooseRayByBRDFDistribution(normalVecN));
double thetaOut = acos(outRay.getDirectionN().dot(normalVecN));
this->brdfPtr->readColor(acos(inRay.getDirectionN().dot(-normalVecN)), 0, thetaOut, M_PI, color);
return true;
}
bool alex::ObjectBase::reflect(const Ray &inRay, const cv::Vec3d &intersection, const cv::Vec3d &normalVecN,
cv::Vec3d &color, Ray &outRay) const {
double cosTheta = -inRay.getDirectionN().dot(normalVecN);
auto front = (normalVecN * (2 * cosTheta) + inRay.getDirectionN());
outRay = Ray(intersection + normalVecN * alex::Epsilon, front);
color = reflectColor;
return true;
}