Daniel Genrich
9f5e42ff76
* Totally new try to get cache running * Didn't try "bake" and such things yet Hint * Very verbose yet * Please do only test new blend files, not old ones! Please give me feedback on my blog about the old crashers.
718 lines
22 KiB
C++
718 lines
22 KiB
C++
//////////////////////////////////////////////////////////////////////
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// This file is part of Wavelet Turbulence.
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//
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// Wavelet Turbulence is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// Wavelet Turbulence is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with Wavelet Turbulence. If not, see <http://www.gnu.org/licenses/>.
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//
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// Copyright 2008 Theodore Kim and Nils Thuerey
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//
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// FLUID_3D.cpp: implementation of the FLUID_3D class.
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//
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//////////////////////////////////////////////////////////////////////
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#include "FLUID_3D.h"
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#include "IMAGE.h"
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#include <INTERPOLATE.h>
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#include "SPHERE.h"
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#include <zlib.h>
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// boundary conditions of the fluid domain
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#define DOMAIN_BC_FRONT 0 // z
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#define DOMAIN_BC_TOP 1 // y
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#define DOMAIN_BC_LEFT 1 // x
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#define DOMAIN_BC_BACK DOMAIN_BC_FRONT
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#define DOMAIN_BC_BOTTOM DOMAIN_BC_TOP
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#define DOMAIN_BC_RIGHT DOMAIN_BC_LEFT
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//////////////////////////////////////////////////////////////////////
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// Construction/Destruction
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//////////////////////////////////////////////////////////////////////
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FLUID_3D::FLUID_3D(int *res, float *p0, float dt) :
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_xRes(res[0]), _yRes(res[1]), _zRes(res[2]), _res(0.0f), _dt(dt)
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{
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// set simulation consts
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// _dt = dt; // 0.10
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// start point of array
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_p0[0] = p0[0];
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_p0[1] = p0[1];
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_p0[2] = p0[2];
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_iterations = 100;
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_tempAmb = 0;
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_heatDiffusion = 1e-3;
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_vorticityEps = 2.0;
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_totalTime = 0.0f;
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_totalSteps = 0;
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_res = Vec3Int(_xRes,_yRes,_zRes);
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_maxRes = MAX3(_xRes, _yRes, _zRes);
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// initialize wavelet turbulence
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/*
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if(amplify)
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_wTurbulence = new WTURBULENCE(_res[0],_res[1],_res[2], amplify, noisetype);
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else
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_wTurbulence = NULL;
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*/
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// scale the constants according to the refinement of the grid
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_dx = 1.0f / (float)_maxRes;
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float scaling = 64.0f / _maxRes;
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scaling = (scaling < 1.0f) ? 1.0f : scaling;
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_vorticityEps /= scaling;
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// allocate arrays
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_totalCells = _xRes * _yRes * _zRes;
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_slabSize = _xRes * _yRes;
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_xVelocity = new float[_totalCells];
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_yVelocity = new float[_totalCells];
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_zVelocity = new float[_totalCells];
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_xVelocityOld = new float[_totalCells];
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_yVelocityOld = new float[_totalCells];
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_zVelocityOld = new float[_totalCells];
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_xForce = new float[_totalCells];
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_yForce = new float[_totalCells];
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_zForce = new float[_totalCells];
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_density = new float[_totalCells];
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_densityOld = new float[_totalCells];
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_heat = new float[_totalCells];
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_heatOld = new float[_totalCells];
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_obstacles = new unsigned char[_totalCells]; // set 0 at end of step
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// DG TODO: check if alloc went fine
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for (int x = 0; x < _totalCells; x++)
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{
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_density[x] = 0.0f;
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_densityOld[x] = 0.0f;
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_heat[x] = 0.0f;
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_heatOld[x] = 0.0f;
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_xVelocity[x] = 0.0f;
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_yVelocity[x] = 0.0f;
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_zVelocity[x] = 0.0f;
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_xVelocityOld[x] = 0.0f;
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_yVelocityOld[x] = 0.0f;
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_zVelocityOld[x] = 0.0f;
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_xForce[x] = 0.0f;
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_yForce[x] = 0.0f;
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_zForce[x] = 0.0f;
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_obstacles[x] = false;
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}
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// set side obstacles
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int index;
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for (int y = 0; y < _yRes; y++)
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for (int x = 0; x < _xRes; x++)
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{
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// front slab
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index = x + y * _xRes;
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if(DOMAIN_BC_FRONT==1) _obstacles[index] = 1;
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// back slab
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index += _totalCells - _slabSize;
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if(DOMAIN_BC_BACK==1) _obstacles[index] = 1;
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}
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for (int z = 0; z < _zRes; z++)
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for (int x = 0; x < _xRes; x++)
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{
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// bottom slab
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index = x + z * _slabSize;
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if(DOMAIN_BC_BOTTOM==1) _obstacles[index] = 1;
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// top slab
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index += _slabSize - _xRes;
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if(DOMAIN_BC_TOP==1) _obstacles[index] = 1;
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}
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for (int z = 0; z < _zRes; z++)
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for (int y = 0; y < _yRes; y++)
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{
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// left slab
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index = y * _xRes + z * _slabSize;
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if(DOMAIN_BC_LEFT==1) _obstacles[index] = 1;
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// right slab
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index += _xRes - 1;
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if(DOMAIN_BC_RIGHT==1) _obstacles[index] = 1;
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}
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}
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FLUID_3D::~FLUID_3D()
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{
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if (_xVelocity) delete[] _xVelocity;
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if (_yVelocity) delete[] _yVelocity;
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if (_zVelocity) delete[] _zVelocity;
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if (_xVelocityOld) delete[] _xVelocityOld;
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if (_yVelocityOld) delete[] _yVelocityOld;
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if (_zVelocityOld) delete[] _zVelocityOld;
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if (_xForce) delete[] _xForce;
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if (_yForce) delete[] _yForce;
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if (_zForce) delete[] _zForce;
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if (_density) delete[] _density;
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if (_densityOld) delete[] _densityOld;
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if (_heat) delete[] _heat;
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if (_heatOld) delete[] _heatOld;
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if (_obstacles) delete[] _obstacles;
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// if (_wTurbulence) delete _wTurbulence;
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// printf("deleted fluid\n");
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}
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// init direct access functions from blender
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void FLUID_3D::initBlenderRNA(float *alpha, float *beta)
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{
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_alpha = alpha;
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_beta = beta;
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}
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//////////////////////////////////////////////////////////////////////
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// step simulation once
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::step()
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{
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// addSmokeTestCase(_density, _res);
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// addSmokeTestCase(_heat, _res);
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// wipe forces
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for (int i = 0; i < _totalCells; i++)
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{
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_xForce[i] = _yForce[i] = _zForce[i] = 0.0f;
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// _obstacles[i] &= ~2;
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}
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wipeBoundaries();
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// run the solvers
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addVorticity();
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addBuoyancy(_heat, _density);
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addForce();
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project();
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diffuseHeat();
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// advect everything
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advectMacCormack();
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// if(_wTurbulence) {
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// _wTurbulence->stepTurbulenceFull(_dt/_dx,
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// _xVelocity, _yVelocity, _zVelocity, _obstacles);
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// _wTurbulence->stepTurbulenceReadable(_dt/_dx,
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// _xVelocity, _yVelocity, _zVelocity, _obstacles);
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// }
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/*
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// no file output
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float *src = _density;
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string prefix = string("./original.preview/density_fullxy_");
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writeImageSliceXY(src,_res, _res[2]/2, prefix, _totalSteps);
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*/
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// artificial damping -- this is necessary because we use a
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// collated grid, and at very coarse grid resolutions, banding
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// artifacts can occur
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artificialDamping(_xVelocity);
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artificialDamping(_yVelocity);
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artificialDamping(_zVelocity);
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/*
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// no file output
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string pbrtPrefix = string("./pbrt/density_small_");
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IMAGE::dumpPBRT(_totalSteps, pbrtPrefix, _density, _res[0],_res[1],_res[2]);
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*/
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_totalTime += _dt;
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_totalSteps++;
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// todo xxx dg: only clear obstacles, not boundaries
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// memset(_obstacles, 0, sizeof(unsigned char)*_xRes*_yRes*_zRes);
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}
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//////////////////////////////////////////////////////////////////////
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// helper function to dampen co-located grid artifacts of given arrays in intervals
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// (only needed for velocity, strength (w) depends on testcase...
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::artificialDamping(float* field) {
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const float w = 0.9;
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if(_totalSteps % 4 == 1) {
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for (int z = 1; z < _res[2]-1; z++)
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for (int y = 1; y < _res[1]-1; y++)
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for (int x = 1+(y+z)%2; x < _res[0]-1; x+=2) {
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const int index = x + y*_res[0] + z * _slabSize;
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field[index] = (1-w)*field[index] + 1./6. * w*(
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field[index+1] + field[index-1] +
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field[index+_res[0]] + field[index-_res[0]] +
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field[index+_slabSize] + field[index-_slabSize] );
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}
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}
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if(_totalSteps % 4 == 3) {
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for (int z = 1; z < _res[2]-1; z++)
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for (int y = 1; y < _res[1]-1; y++)
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for (int x = 1+(y+z+1)%2; x < _res[0]-1; x+=2) {
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const int index = x + y*_res[0] + z * _slabSize;
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field[index] = (1-w)*field[index] + 1./6. * w*(
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field[index+1] + field[index-1] +
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field[index+_res[0]] + field[index-_res[0]] +
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field[index+_slabSize] + field[index-_slabSize] );
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}
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}
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}
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//////////////////////////////////////////////////////////////////////
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// copy out the boundary in all directions
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::copyBorderAll(float* field)
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{
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int index;
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for (int y = 0; y < _yRes; y++)
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for (int x = 0; x < _xRes; x++)
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{
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// front slab
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index = x + y * _xRes;
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field[index] = field[index + _slabSize];
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// back slab
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index += _totalCells - _slabSize;
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field[index] = field[index - _slabSize];
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}
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for (int z = 0; z < _zRes; z++)
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for (int x = 0; x < _xRes; x++)
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{
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// bottom slab
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index = x + z * _slabSize;
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field[index] = field[index + _xRes];
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// top slab
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index += _slabSize - _xRes;
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field[index] = field[index - _xRes];
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}
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for (int z = 0; z < _zRes; z++)
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for (int y = 0; y < _yRes; y++)
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{
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// left slab
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index = y * _xRes + z * _slabSize;
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field[index] = field[index + 1];
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// right slab
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index += _xRes - 1;
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field[index] = field[index - 1];
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}
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}
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//////////////////////////////////////////////////////////////////////
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// wipe boundaries of velocity and density
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::wipeBoundaries()
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{
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setZeroBorder(_xVelocity, _res);
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setZeroBorder(_yVelocity, _res);
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setZeroBorder(_zVelocity, _res);
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setZeroBorder(_density, _res);
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}
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//////////////////////////////////////////////////////////////////////
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// add forces to velocity field
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::addForce()
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{
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for (int i = 0; i < _totalCells; i++)
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{
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_xVelocity[i] += _dt * _xForce[i];
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_yVelocity[i] += _dt * _yForce[i];
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_zVelocity[i] += _dt * _zForce[i];
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}
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}
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//////////////////////////////////////////////////////////////////////
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// project into divergence free field
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::project()
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{
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int x, y, z;
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size_t index;
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float *_pressure = new float[_totalCells];
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float *_divergence = new float[_totalCells];
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memset(_pressure, 0, sizeof(float)*_totalCells);
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memset(_divergence, 0, sizeof(float)*_totalCells);
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setObstacleBoundaries(_pressure);
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// copy out the boundaries
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if(DOMAIN_BC_LEFT == 0) setNeumannX(_xVelocity, _res);
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else setZeroX(_xVelocity, _res);
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if(DOMAIN_BC_TOP == 0) setNeumannY(_yVelocity, _res);
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else setZeroY(_yVelocity, _res);
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if(DOMAIN_BC_FRONT == 0) setNeumannZ(_zVelocity, _res);
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else setZeroZ(_zVelocity, _res);
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// calculate divergence
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index = _slabSize + _xRes + 1;
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for (z = 1; z < _zRes - 1; z++, index += 2 * _xRes)
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for (y = 1; y < _yRes - 1; y++, index += 2)
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for (x = 1; x < _xRes - 1; x++, index++)
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{
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float xright = _xVelocity[index + 1];
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float xleft = _xVelocity[index - 1];
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float yup = _yVelocity[index + _xRes];
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float ydown = _yVelocity[index - _xRes];
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float ztop = _zVelocity[index + _slabSize];
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float zbottom = _zVelocity[index - _slabSize];
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if(_obstacles[index+1]) xright = - _xVelocity[index];
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if(_obstacles[index-1]) xleft = - _xVelocity[index];
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if(_obstacles[index+_xRes]) yup = - _yVelocity[index];
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if(_obstacles[index-_xRes]) ydown = - _yVelocity[index];
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if(_obstacles[index+_slabSize]) ztop = - _zVelocity[index];
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if(_obstacles[index-_slabSize]) zbottom = - _zVelocity[index];
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_divergence[index] = -_dx * 0.5f * (
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xright - xleft +
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yup - ydown +
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ztop - zbottom );
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// DG: commenting this helps CG to get a better start, 10-20% speed improvement
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// _pressure[index] = 0.0f;
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}
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copyBorderAll(_pressure);
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// solve Poisson equation
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solvePressurePre(_pressure, _divergence, _obstacles);
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setObstaclePressure(_pressure);
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// project out solution
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float invDx = 1.0f / _dx;
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index = _slabSize + _xRes + 1;
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for (z = 1; z < _zRes - 1; z++, index += 2 * _xRes)
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for (y = 1; y < _yRes - 1; y++, index += 2)
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for (x = 1; x < _xRes - 1; x++, index++)
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{
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// if(!_obstacles[index])
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{
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_xVelocity[index] -= 0.5f * (_pressure[index + 1] - _pressure[index - 1]) * invDx;
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_yVelocity[index] -= 0.5f * (_pressure[index + _xRes] - _pressure[index - _xRes]) * invDx;
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_zVelocity[index] -= 0.5f * (_pressure[index + _slabSize] - _pressure[index - _slabSize]) * invDx;
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}/*
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else
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{
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_xVelocity[index] = _yVelocity[index] = _zVelocity[index] = 0.0f;
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}*/
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}
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if (_pressure) delete[] _pressure;
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if (_divergence) delete[] _divergence;
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}
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//////////////////////////////////////////////////////////////////////
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// diffuse heat
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::diffuseHeat()
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{
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SWAP_POINTERS(_heat, _heatOld);
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copyBorderAll(_heatOld);
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solveHeat(_heat, _heatOld, _obstacles);
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// zero out inside obstacles
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for (int x = 0; x < _totalCells; x++)
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if (_obstacles[x])
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_heat[x] = 0.0f;
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}
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//////////////////////////////////////////////////////////////////////
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// stamp an obstacle in the _obstacles field
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::addObstacle(OBSTACLE* obstacle)
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{
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int index = 0;
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for (int z = 0; z < _zRes; z++)
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for (int y = 0; y < _yRes; y++)
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for (int x = 0; x < _xRes; x++, index++)
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if (obstacle->inside(x * _dx, y * _dx, z * _dx)) {
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_obstacles[index] = true;
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}
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}
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//////////////////////////////////////////////////////////////////////
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// calculate the obstacle directional types
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//////////////////////////////////////////////////////////////////////
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void FLUID_3D::setObstaclePressure(float *_pressure)
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{
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// tag remaining obstacle blocks
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for (int z = 1, index = _slabSize + _xRes + 1;
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z < _zRes - 1; z++, index += 2 * _xRes)
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for (int y = 1; y < _yRes - 1; y++, index += 2)
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for (int x = 1; x < _xRes - 1; x++, index++)
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{
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// could do cascade of ifs, but they are a pain
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if (_obstacles[index])
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{
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const int top = _obstacles[index + _slabSize];
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const int bottom= _obstacles[index - _slabSize];
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const int up = _obstacles[index + _xRes];
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const int down = _obstacles[index - _xRes];
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const int left = _obstacles[index - 1];
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const int right = _obstacles[index + 1];
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// unused
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// const bool fullz = (top && bottom);
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// const bool fully = (up && down);
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//const bool fullx = (left && right);
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_xVelocity[index] =
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_yVelocity[index] =
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_zVelocity[index] = 0.0f;
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_pressure[index] = 0.0f;
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// average pressure neighbors
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float pcnt = 0.;
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if (left && !right) {
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_pressure[index] += _pressure[index + 1];
|
|
pcnt += 1.;
|
|
}
|
|
if (!left && right) {
|
|
_pressure[index] += _pressure[index - 1];
|
|
pcnt += 1.;
|
|
}
|
|
if (up && !down) {
|
|
_pressure[index] += _pressure[index - _xRes];
|
|
pcnt += 1.;
|
|
}
|
|
if (!up && down) {
|
|
_pressure[index] += _pressure[index + _xRes];
|
|
pcnt += 1.;
|
|
}
|
|
if (top && !bottom) {
|
|
_pressure[index] += _pressure[index - _slabSize];
|
|
pcnt += 1.;
|
|
// _zVelocity[index] += - _zVelocity[index - _slabSize];
|
|
// vp += 1.0;
|
|
}
|
|
if (!top && bottom) {
|
|
_pressure[index] += _pressure[index + _slabSize];
|
|
pcnt += 1.;
|
|
// _zVelocity[index] += - _zVelocity[index + _slabSize];
|
|
// vp += 1.0;
|
|
}
|
|
|
|
if(pcnt > 0.000001f)
|
|
_pressure[index] /= pcnt;
|
|
|
|
// test - dg
|
|
// if(vp > 0.000001f)
|
|
// _zVelocity[index] /= vp;
|
|
|
|
// TODO? set correct velocity bc's
|
|
// velocities are only set to zero right now
|
|
// this means it's not a full no-slip boundary condition
|
|
// but a "half-slip" - still looks ok right now
|
|
}
|
|
}
|
|
}
|
|
|
|
void FLUID_3D::setObstacleBoundaries(float *_pressure)
|
|
{
|
|
// cull degenerate obstacles , move to addObstacle?
|
|
for (int z = 1, index = _slabSize + _xRes + 1;
|
|
z < _zRes - 1; z++, index += 2 * _xRes)
|
|
for (int y = 1; y < _yRes - 1; y++, index += 2)
|
|
for (int x = 1; x < _xRes - 1; x++, index++)
|
|
{
|
|
if (_obstacles[index] != EMPTY)
|
|
{
|
|
const int top = _obstacles[index + _slabSize];
|
|
const int bottom= _obstacles[index - _slabSize];
|
|
const int up = _obstacles[index + _xRes];
|
|
const int down = _obstacles[index - _xRes];
|
|
const int left = _obstacles[index - 1];
|
|
const int right = _obstacles[index + 1];
|
|
|
|
int counter = 0;
|
|
if (up) counter++;
|
|
if (down) counter++;
|
|
if (left) counter++;
|
|
if (right) counter++;
|
|
if (top) counter++;
|
|
if (bottom) counter++;
|
|
|
|
if (counter < 3)
|
|
_obstacles[index] = EMPTY;
|
|
}
|
|
if (_obstacles[index])
|
|
{
|
|
_xVelocity[index] =
|
|
_yVelocity[index] =
|
|
_zVelocity[index] = 0.0f;
|
|
_pressure[index] = 0.0f;
|
|
}
|
|
}
|
|
}
|
|
|
|
//////////////////////////////////////////////////////////////////////
|
|
// add buoyancy forces
|
|
//////////////////////////////////////////////////////////////////////
|
|
void FLUID_3D::addBuoyancy(float *heat, float *density)
|
|
{
|
|
int index = 0;
|
|
|
|
for (int z = 0; z < _zRes; z++)
|
|
for (int y = 0; y < _yRes; y++)
|
|
for (int x = 0; x < _xRes; x++, index++)
|
|
{
|
|
_zForce[index] += *_alpha * density[index] + (*_beta * (heat[index] - _tempAmb)); // DG: was _yForce, changed for Blender
|
|
}
|
|
}
|
|
|
|
//////////////////////////////////////////////////////////////////////
|
|
// add vorticity to the force field
|
|
//////////////////////////////////////////////////////////////////////
|
|
void FLUID_3D::addVorticity()
|
|
{
|
|
int x,y,z,index;
|
|
if(_vorticityEps<=0.) return;
|
|
|
|
float *_xVorticity, *_yVorticity, *_zVorticity, *_vorticity;
|
|
|
|
_xVorticity = new float[_totalCells];
|
|
_yVorticity = new float[_totalCells];
|
|
_zVorticity = new float[_totalCells];
|
|
_vorticity = new float[_totalCells];
|
|
|
|
memset(_xVorticity, 0, sizeof(float)*_totalCells);
|
|
memset(_yVorticity, 0, sizeof(float)*_totalCells);
|
|
memset(_zVorticity, 0, sizeof(float)*_totalCells);
|
|
memset(_vorticity, 0, sizeof(float)*_totalCells);
|
|
|
|
// calculate vorticity
|
|
float gridSize = 0.5f / _dx;
|
|
index = _slabSize + _xRes + 1;
|
|
for (z = 1; z < _zRes - 1; z++, index += 2 * _xRes)
|
|
for (y = 1; y < _yRes - 1; y++, index += 2)
|
|
for (x = 1; x < _xRes - 1; x++, index++)
|
|
{
|
|
int up = _obstacles[index + _xRes] ? index : index + _xRes;
|
|
int down = _obstacles[index - _xRes] ? index : index - _xRes;
|
|
float dy = (up == index || down == index) ? 1.0f / _dx : gridSize;
|
|
int out = _obstacles[index + _slabSize] ? index : index + _slabSize;
|
|
int in = _obstacles[index - _slabSize] ? index : index - _slabSize;
|
|
float dz = (out == index || in == index) ? 1.0f / _dx : gridSize;
|
|
int right = _obstacles[index + 1] ? index : index + 1;
|
|
int left = _obstacles[index - 1] ? index : index - 1;
|
|
float dx = (right == index || right == index) ? 1.0f / _dx : gridSize;
|
|
|
|
_xVorticity[index] = (_zVelocity[up] - _zVelocity[down]) * dy + (-_yVelocity[out] + _yVelocity[in]) * dz;
|
|
_yVorticity[index] = (_xVelocity[out] - _xVelocity[in]) * dz + (-_zVelocity[right] + _zVelocity[left]) * dx;
|
|
_zVorticity[index] = (_yVelocity[right] - _yVelocity[left]) * dx + (-_xVelocity[up] + _xVelocity[down])* dy;
|
|
|
|
_vorticity[index] = sqrtf(_xVorticity[index] * _xVorticity[index] +
|
|
_yVorticity[index] * _yVorticity[index] +
|
|
_zVorticity[index] * _zVorticity[index]);
|
|
}
|
|
|
|
// calculate normalized vorticity vectors
|
|
float eps = _vorticityEps;
|
|
index = _slabSize + _xRes + 1;
|
|
for (z = 1; z < _zRes - 1; z++, index += 2 * _xRes)
|
|
for (y = 1; y < _yRes - 1; y++, index += 2)
|
|
for (x = 1; x < _xRes - 1; x++, index++)
|
|
if (!_obstacles[index])
|
|
{
|
|
float N[3];
|
|
|
|
int up = _obstacles[index + _xRes] ? index : index + _xRes;
|
|
int down = _obstacles[index - _xRes] ? index : index - _xRes;
|
|
float dy = (up == index || down == index) ? 1.0f / _dx : gridSize;
|
|
int out = _obstacles[index + _slabSize] ? index : index + _slabSize;
|
|
int in = _obstacles[index - _slabSize] ? index : index - _slabSize;
|
|
float dz = (out == index || in == index) ? 1.0f / _dx : gridSize;
|
|
int right = _obstacles[index + 1] ? index : index + 1;
|
|
int left = _obstacles[index - 1] ? index : index - 1;
|
|
float dx = (right == index || right == index) ? 1.0f / _dx : gridSize;
|
|
N[0] = (_vorticity[right] - _vorticity[left]) * dx;
|
|
N[1] = (_vorticity[up] - _vorticity[down]) * dy;
|
|
N[2] = (_vorticity[out] - _vorticity[in]) * dz;
|
|
|
|
float magnitude = sqrtf(N[0] * N[0] + N[1] * N[1] + N[2] * N[2]);
|
|
if (magnitude > 0.0f)
|
|
{
|
|
magnitude = 1.0f / magnitude;
|
|
N[0] *= magnitude;
|
|
N[1] *= magnitude;
|
|
N[2] *= magnitude;
|
|
|
|
_xForce[index] += (N[1] * _zVorticity[index] - N[2] * _yVorticity[index]) * _dx * eps;
|
|
_yForce[index] -= (N[0] * _zVorticity[index] - N[2] * _xVorticity[index]) * _dx * eps;
|
|
_zForce[index] += (N[0] * _yVorticity[index] - N[1] * _xVorticity[index]) * _dx * eps;
|
|
}
|
|
}
|
|
|
|
if (_xVorticity) delete[] _xVorticity;
|
|
if (_yVorticity) delete[] _yVorticity;
|
|
if (_zVorticity) delete[] _zVorticity;
|
|
if (_vorticity) delete[] _vorticity;
|
|
}
|
|
|
|
//////////////////////////////////////////////////////////////////////
|
|
// Advect using the MacCormack method from the Selle paper
|
|
//////////////////////////////////////////////////////////////////////
|
|
void FLUID_3D::advectMacCormack()
|
|
{
|
|
Vec3Int res = Vec3Int(_xRes,_yRes,_zRes);
|
|
|
|
if(DOMAIN_BC_LEFT == 0) copyBorderX(_xVelocity, res);
|
|
else setZeroX(_xVelocity, res);
|
|
|
|
if(DOMAIN_BC_TOP == 0) copyBorderY(_yVelocity, res);
|
|
else setZeroY(_yVelocity, res);
|
|
|
|
if(DOMAIN_BC_FRONT == 0) copyBorderZ(_zVelocity, res);
|
|
else setZeroZ(_zVelocity, res);
|
|
|
|
SWAP_POINTERS(_xVelocity, _xVelocityOld);
|
|
SWAP_POINTERS(_yVelocity, _yVelocityOld);
|
|
SWAP_POINTERS(_zVelocity, _zVelocityOld);
|
|
SWAP_POINTERS(_density, _densityOld);
|
|
SWAP_POINTERS(_heat, _heatOld);
|
|
|
|
const float dt0 = _dt / _dx;
|
|
// use force arrays as temp arrays
|
|
for (int x = 0; x < _totalCells; x++)
|
|
_xForce[x] = _yForce[x] = 0.0;
|
|
|
|
float* t1 = _xForce;
|
|
float* t2 = _yForce;
|
|
|
|
advectFieldMacCormack(dt0, _xVelocityOld, _yVelocityOld, _zVelocityOld, _densityOld, _density, t1,t2, res, _obstacles);
|
|
advectFieldMacCormack(dt0, _xVelocityOld, _yVelocityOld, _zVelocityOld, _heatOld, _heat, t1,t2, res, _obstacles);
|
|
advectFieldMacCormack(dt0, _xVelocityOld, _yVelocityOld, _zVelocityOld, _xVelocityOld, _xVelocity, t1,t2, res, _obstacles);
|
|
advectFieldMacCormack(dt0, _xVelocityOld, _yVelocityOld, _zVelocityOld, _yVelocityOld, _yVelocity, t1,t2, res, _obstacles);
|
|
advectFieldMacCormack(dt0, _xVelocityOld, _yVelocityOld, _zVelocityOld, _zVelocityOld, _zVelocity, t1,t2, res, _obstacles);
|
|
|
|
if(DOMAIN_BC_LEFT == 0) copyBorderX(_xVelocity, res);
|
|
else setZeroX(_xVelocity, res);
|
|
|
|
if(DOMAIN_BC_TOP == 0) copyBorderY(_yVelocity, res);
|
|
else setZeroY(_yVelocity, res);
|
|
|
|
if(DOMAIN_BC_FRONT == 0) copyBorderZ(_zVelocity, res);
|
|
else setZeroZ(_zVelocity, res);
|
|
|
|
setZeroBorder(_density, res);
|
|
setZeroBorder(_heat, res);
|
|
|
|
for (int x = 0; x < _totalCells; x++)
|
|
t1[x] = t2[x] = 0.0;
|
|
}
|