void RodSoundApp::loadDefaultRod(int numPoints) { if (r) delete r; Vec3e start = Vec3e(0.0, 1.9144, 0.0); // Vec3e(0.5, 1.0, 0.5); Vec3e end = Vec3e(0.0, 1.0, 0.0); // start + (Vec3e(-1.0, -1.0, -1.0).normalized() * 0.6069); // 1ft. = 0.3048m // 2ft. = 0.6069m // 3ft. = 0.9144m Vec3e u = (end-start).cross(Vec3e(0.0, 0.1, 0.0)).normalized(); if (u.hasNaN() || u.norm() < 0.95) { u << 1.0, 0.0, 0.0; } VecXe rodPos(3*numPoints); for(int i=0; i < numPoints; i++) { real t = ((real) i) / (real) (numPoints -1); rodPos.segment<3>(3*i) = (1-t)*start + t*end; } eyePos = Vec3c(5.0, 1.5, 0.0); targetPos = Vec3c(0.0, 1.5, 0.0); cam.lookAt(eyePos, targetPos, Vec3c(0.0, 1.0, 0.0)); // FIXME: assumes circular cylindrical rod of default radius real totalMass = constants::radius * constants::radius * constants::pi * (start - end).norm() * constants::rhoRod; real massPerPoint = totalMass / numPoints; VecXe mass = VecXe::Constant(numPoints, massPerPoint); r = new Rod(rodPos, u, &mass); real l = (start - end).norm(); real kappa = sqrt(r->youngsModulus * r->getCS()[0].areaMoment()(0, 0) / (constants::rhoRod * r->getCS()[0].area() * l * l * l * l)); std::cout << "kappa: " << kappa << "\n"; real h = l / (numPoints-1); real k = 1.0 / (44100*multiSample); real mu = kappa * k / (h * h); std::cout << "mu: " << mu << "\n"; real fmax = asin(2.0 * mu) / (constants::pi * k); std::cout << "fmax: " << fmax << "\n"; /* real cb = std::pow(constants::youngsModulus * r->getCS()[0].areaMoment()(0, 0) / constants::rhoRod / r->getCS()[0].area(), 0.25); real cbHigh = cb * 141.4; real cbLow = cb * 4.47; real dx = (start - end).norm() / (numPoints - 1.0); std::cout << "Min timestep: " << dx / cbHigh << "\n"; */ }
bool IMEXIntegrator::setRotations() const { const real newtonThreshold = 1.0e-5; //should be able to get this almost exact std::vector<Triplet> triplets; Eigen::SparseMatrix<real> hess(r.numEdges()-2, r.numEdges()-2); VecXe rot = r.next().rot; VecXe grad = VecXe::Zero(r.numEdges()-2); // Assumes edges are clamped bool newtonConverge = false; std::vector<Vec3e> curveBinorm; for (int i=1; i<r.numCPs()-1; i++) { Vec3e tPrev = r.next().edge(i-1).normalized(); Vec3e tNext = r.next().edge(i).normalized(); real chi = 1.0 + (tPrev.dot(tNext)); curveBinorm.push_back(2.0*tPrev.cross(tNext)/chi); } int newtonIterations = 0; do { triplets.clear(); calcRotEqs(r, rot, curveBinorm, grad, triplets); real resid = grad.norm(); if (resid < newtonThreshold || newtonIterations > 4) { if (resid > 1.0e-5 * r.numEdges()) { return false; } newtonConverge = true; break; } newtonIterations++; hess.setFromTriplets(triplets.begin(), triplets.end()); hess += hessBase; Eigen::SimplicialLDLT<Eigen::SparseMatrix<real>> sLDLT; sLDLT.compute(hess); VecXe sol = sLDLT.solve(grad); assert(sLDLT.info() == Eigen::Success); rot.block(1, 0, r.numEdges()-2, 1) += sol; } while (!newtonConverge); if (newtonConverge) { r.next().rot = rot; } return newtonConverge; }
void RodSoundApp::update() { if (!running) return; if (curSample % 5000 == 0 && curSample != 0 && c.getTicks() % multiSample == 0) { std::cout << curSample << " / " << BufferSize << " (" << (curSample*100.0)/BufferSize << "%)\n"; PROFILER_PRINT_ELAPSED(); PROFILER_RESET_ALL(); std::cout << "\n"; } if (curSample >= BufferSize || stopNow) { // We're done! sampleBuffer[0] = 0.0; // To prevent the click of forces suddenly being applied double max = 0; for (int i=0; i<BufferSize; i++) { max = std::max(max, std::fabs(sampleBuffer[i])); } std::cout << "Max1: " << max << "\n"; uint16_t buffer[BufferSize]; for (int i=0; i<BufferSize; i++) { buffer[i] = toSample(sampleBuffer[i], max); } writeWAVData((constants::ResultPath+"result.wav").data(), buffer, curSample * sizeof(uint16_t), SampleRate, 1); sampleBuffer2[0] = 0.0; max = 0; for (int i=0; i<BufferSize; i++) { max = std::max(max, std::fabs(sampleBuffer2[i])); } std::cout << "Max2: " << max << "\n"; for (int i=0; i<BufferSize; i++) { buffer[i] = toSample(sampleBuffer2[i], max); } writeWAVData((constants::ResultPath+"result2.wav").data(), buffer, curSample * sizeof(uint16_t), SampleRate, 1); sampleBuffer3[0] = 0.0; max = 0; for (int i=0; i<BufferSize; i++) { max = std::max(max, std::fabs(sampleBuffer3[i])); } std::cout << "Max3: " << max << "\n"; for (int i=0; i<BufferSize; i++) { buffer[i] = toSample(sampleBuffer3[i], max); } writeWAVData((constants::ResultPath+"result3.wav").data(), buffer, curSample * sizeof(uint16_t), SampleRate, 1); fe.writeMPEG("result"); std::cout << "Total simulation time: " << app::getElapsedSeconds() << "\n"; // FIXME: This is inaccurate running = false; return; } PROFILER_START("Update"); c.suggestTimestep(1.0 / (real) SampleRate / multiSample); // FIXME: Normally the frame exporter would suggest a timestep, but this interferes with the audio // recording, as it assumes all timesteps are 1/SampleRate. However, any error the frame exporter // experiences is small since 1/60 >> 1/SampleRate. // fe.suggestTimestep(c); Vec3e mp; if (isMouseDown) mp << mousePosition.x, mousePosition.y, mousePosition.z; mouseSpring->setMouse(mp, isMouseDown); if (!integrator->integrate(c)) throw; /// Update Bishop frame r->next().updateReferenceFrames(r->cur()); // Sound Calculations if (c.getTicks() % multiSample == 0) { real sample = 0; real sample2 = 0; real avgX = 0; VecXe jerkVec = r->next().dVel - r->cur().dVel; for (int i=1; i<r->numCPs()-1; i++) { avgX += r->next().VEL(i).x(); // Calculate jerk Vec3e jerk = jerkVec.segment<3>(3*i); // Project jerk to transverse plane Vec3e tPlaneNormal = (r->next().edge(i-1) + r->next().edge(i)).normalized(); jerk = jerk - jerk.dot(tPlaneNormal) * tPlaneNormal; // Vector rejection of jerk from tPlaneNormal /* real m0 = r->restVoronoiLength(i)*constants::pi*r->radius()*r->radius()*constants::rhoAir; // Rotation to align system so that the cylinder is coaxial with the z-axis Eigen::Quaternion<real> q = Eigen::Quaternion<real>::FromTwoVectors(tPlaneNormal, Vec3e(0, 0, 1)); Vec3e rotJerk = q * jerk; rotJerk = rotJerk.cwiseProduct(Vec3e(2.0*m0, 2.0*m0, m0)); // Calculate sample contribution Vec3e earVec = CtoE(eyePos) - r->next().points[i].pos; sample += (q * earVec).dot(rotJerk) / (4.0 * constants::pi * constants::cAir * earVec.dot(earVec)); earVec = ear2Pos - r->next().points[i].pos; sample2 += (q * earVec).dot(rotJerk) / (4.0 * constants::pi * constants::cAir * earVec.dot(earVec)); */ Vec3e earVec = CtoE(eyePos) - r->next().POS(i); // Calculate sample contribution sample += r->getCS()[i].calcSample(earVec, jerk); earVec = ear2Pos - r->next().POS(i); sample2 += r->getCS()[i].calcSample(earVec, jerk); } avgX = avgX/(r->numCPs()-2); sampleBuffer[curSample] = sample; sampleBuffer2[curSample] = sample2; sampleBuffer3[curSample] = r->next().VEL(r->numCPs()/2).x() - avgX; curSample++; } // Swap Rods r->swapRods(); c.increment(); PROFILER_STOP("Update"); }