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proceduralcity/source/main.cpp
2016-11-24 12:33:20 -06:00

292 lines
9.3 KiB
C++

//Computational Fabrication Assignment #1
// Created by David Levin 2014
// Modified by Shinjiro Sueda 2016
#include <iostream>
#include <vector>
#include "../include/CompFab.h"
#include "../include/Mesh.h"
//Triangle list (global)
typedef std::vector<CompFab::Triangle> TriangleList;
TriangleList g_triangleList;
CompFab::VoxelGrid *g_voxelGrid;
bool loadMesh(char *filename, unsigned int num)
{
g_triangleList.clear();
Mesh *tempMesh = new Mesh(filename, true);
CompFab::Vec3 v1, v2, v3;
//copy triangles to global list
for(unsigned int tri =0; tri<tempMesh->t.size(); ++tri)
{
v1 = tempMesh->v[tempMesh->t[tri][0]];
v2 = tempMesh->v[tempMesh->t[tri][1]];
v3 = tempMesh->v[tempMesh->t[tri][2]];
g_triangleList.push_back(CompFab::Triangle(v1,v2,v3));
}
//Create Voxel Grid
CompFab::Vec3 bbMax, bbMin;
BBox(*tempMesh, bbMin, bbMax);
//Build Voxel Grid
double bbX = bbMax[0] - bbMin[0];
double bbY = bbMax[1] - bbMin[1];
double bbZ = bbMax[2] - bbMin[2];
double spacing;
if(bbX > bbY && bbX > bbZ)
{
spacing = bbX/(num-1);
} else if(bbY > bbX && bbY > bbZ) {
spacing = bbY/(num-1);
} else {
spacing = bbZ/(num-1);
}
g_voxelGrid = new CompFab::VoxelGrid(bbMin, num, num, num, spacing);
delete tempMesh;
return true;
}
void saveVoxelsToObj(const char * outfile)
{
Mesh box;
Mesh mout;
int nx = g_voxelGrid->m_numX;
int ny = g_voxelGrid->m_numY;
int nz = g_voxelGrid->m_numZ;
double spacing = g_voxelGrid->m_spacing;
CompFab::Vec3 hspacing(0.5*spacing, 0.5*spacing, 0.5*spacing);
for (int ii = 0; ii < nx; ii++) {
for (int jj = 0; jj < ny; jj++) {
for (int kk = 0; kk < nz; kk++) {
if(!g_voxelGrid->isInside(ii,jj,kk)){
continue;
}
CompFab::Vec3 coord(0.5f + ((double)ii)*spacing, 0.5f + ((double)jj)*spacing, 0.5f+((double)kk)*spacing);
CompFab::Vec3 box0 = coord - hspacing;
CompFab::Vec3 box1 = coord + hspacing;
makeCube(box, box0, box1);
mout.append(box);
}
}
}
mout.save_obj(outfile);
}
// Code referenced is sourced in README.txt
bool triangleIntersection(CompFab::Vec3 V1, CompFab::Vec3 V2, CompFab::Vec3 V3, CompFab::Vec3 O, CompFab::Vec3 D)
{
CompFab::Vec3 e1, e2; //Edge1, Edge2
CompFab::Vec3 P, Q, T;
double det, inv_det, u, v;
double t;
//Find vectors for two edges sharing V1
e1 = V2 - V1;
e2 = V3 - V1;
//Begin calculating determinant - also used to calculate u parameter
P = D % e2;
//if determinant is near zero, ray lies in plane of triangle or ray is parallel to plane of triangle
det = e1 * P;
//NOT CULLING
if (det > -EPSILON && det < EPSILON) return false;
inv_det = 1.f / det;
//calculate distance from V1 to ray origin
T = O - V1;
//Calculate u parameter and test bound
u = (T * P) * inv_det;
//The intersection lies outside of the triangle
if (u < 0.f || u > 1.f) return false;
//Prepare to test v parameter
Q = T % e1;
//Calculate V parameter and test bound
v = (D * Q) * inv_det;
//The intersection lies outside of the triangle
if (v < 0.f || u + v > 1.f) return false;
t = (e2 * Q) * inv_det;
if (t > EPSILON) { //ray intersection
return true;
}
// No hit, no win
return false;
}
int castRays(CompFab::Vec3 t_origin)
{
// 6 separate counter variables for the 6 raycasts. Additional coutner to count how many of them counted a voxel as being "inside"
int rc = 0, c1 = 0, c2 = 0, c3 = 0, c4 = 0, c5 = 0, c6 = 0;
// Calculating triangle intersections for each triangle with all 6 raycasts.
for (int i = 0; i < g_triangleList.size(); i++)
{
if (triangleIntersection(g_triangleList.at(i).m_v1, g_triangleList.at(i).m_v2, g_triangleList.at(i).m_v3, t_origin, CompFab::Vec3(1, 0, 0)))
{
++c1;
}
if (triangleIntersection(g_triangleList.at(i).m_v1, g_triangleList.at(i).m_v2, g_triangleList.at(i).m_v3, t_origin, CompFab::Vec3(-1, 0, 0)))
{
++c2;
}
if (triangleIntersection(g_triangleList.at(i).m_v1, g_triangleList.at(i).m_v2, g_triangleList.at(i).m_v3, t_origin, CompFab::Vec3(0, 1, 0)))
{
++c3;
}
if (triangleIntersection(g_triangleList.at(i).m_v1, g_triangleList.at(i).m_v2, g_triangleList.at(i).m_v3, t_origin, CompFab::Vec3(0, -1, 0)))
{
++c4;
}
if (triangleIntersection(g_triangleList.at(i).m_v1, g_triangleList.at(i).m_v2, g_triangleList.at(i).m_v3, t_origin, CompFab::Vec3(0, 0, 1)))
{
++c5;
}
if (triangleIntersection(g_triangleList.at(i).m_v1, g_triangleList.at(i).m_v2, g_triangleList.at(i).m_v3, t_origin, CompFab::Vec3(0, 0, -1)))
{
++c6;
}
}
// Determining which triangle intersections were valid.
if (c1 % 2 == 1) ++rc;
if (c2 % 2 == 1) ++rc;
if (c3 % 2 == 1) ++rc;
if (c4 % 2 == 1) ++rc;
if (c5 % 2 == 1) ++rc;
if (c6 % 2 == 1) ++rc;
return rc;
}
void findLW(Mesh &m, double &l, double &w)
{
double minl, maxl, minw, maxw;
for(int i = 0; i < m.t.size(); i++)
{
if(m.v[i].m_x < minl)
{
minl = m.v[i].m_x;
}
if(m.v[i].m_x > maxl)
{
maxl = m.v[i].m_x;
}
if(m.v[i].m_y < minw)
{
minw = m.v[i].m_x;
}
if(m.v[i].m_y > maxw)
{
maxw = m.v[i].m_x;
}
}
l = maxl - minl;
w = maxw - minw;
}
int main(int argc, char **argv)
{
unsigned int num = 16; //number of voxels (e.g. 16x16x16)
if(argc < 4)
{
Mesh *test = new Mesh(argv[1], false);
Mesh *output = new Mesh(test->v, test->t);
double l = 0, w = 0;
double *length = &l, *width = &w;
findLW(*test, *length, *width);
for(int i = 0; i < test->v.size(); i++)
{
output->v.push_back(*new CompFab::Vec3(test->v[i].m_x + *length + 1, test->v[i].m_y, test->v[i].m_z));
}
for(int k = 0; k < test->t.size(); k++)
{
output->t.push_back(*new CompFab::Vec3i(test->t[k].m_x + test->v.size(), test->t[k].m_y + test->v.size(), test->t[k].m_z + test->v.size()));
}
for(int j = 0; j < output->v.size(); j++)
{
std::cout << output->v[j].m_x << " " << output->v[j].m_y << " " << output->v[j].m_z << std::endl;
std::cout << output->t[j].m_x << " " << output->t[j].m_y << " " << output->t[j].m_z << std::endl;
std::cout << std::endl;
}
output->save(argv[2]);
}
else
{
num = atoi(argv[3]);
// The loadMesh() function loads the mesh and then creates:
// - g_triangleList: The list of triangles in the input OBJ mesh
// - g_voxelGrid: The VoxelGrid object, with all voxels marked as unoccupied
std::cout<<"Load Mesh : "<<argv[1]<<"\n";
loadMesh(argv[1], num);
std::cout<<"Voxelizing into "<<num<<"x"<<num<<"x"<<num<<"\n";
// Below, write a triple for-loop to go through all the voxels in X, Y, Z.
// g_voxelGrid->m_numX is the number of voxels in the X direction.
// g_voxelGrid->m_numY is the number of voxels in the Y direction.
// g_voxelGrid->m_numZ is the number of voxels in the Z direction.
// g_voxelGrid->m_spacing is the size of each voxel.
//
// Inside the triple for-loop, check if the voxel is inside or outside the
// mesh. Use the g_voxelGrid->isInside(...) method to set whether that voxel
// is inside or outside. E.g.,
// g_voxelGrid->isInside(0,0,0) = false;
// <TRIPLE FOR-LOOP HERE>
// Temp varaible for the current corner
CompFab::Vec3 t_corner = g_voxelGrid->m_corner;
// Temp varaible for the current center
CompFab::Vec3 t_origin;
for (unsigned int i_x = 0; i_x < g_voxelGrid->m_numX; i_x++)
{
for (unsigned int i_y = 0; i_y < g_voxelGrid->m_numY; i_y++)
{
for (unsigned int i_z = 0; i_z < g_voxelGrid->m_numZ; i_z++)
{
// Finding the corner of the current voxel.
t_corner.m_x = g_voxelGrid->m_corner.m_x + i_x*g_voxelGrid->m_spacing;
t_corner.m_y = g_voxelGrid->m_corner.m_y + i_y*g_voxelGrid->m_spacing;
t_corner.m_z = g_voxelGrid->m_corner.m_z + i_z*g_voxelGrid->m_spacing;
// Finding the origin of the current voxel.
t_origin.m_x = t_corner.m_x + 0.5*g_voxelGrid->m_spacing;
t_origin.m_y = t_corner.m_y + 0.5*g_voxelGrid->m_spacing;
t_origin.m_z = t_corner.m_z + 0.5*g_voxelGrid->m_spacing;
// Will say "inside" if 4 or more of the raycasts determine a voxel to be inside.
g_voxelGrid->isInside(i_x, i_y, i_z) = (castRays(t_origin) >= 4);
}
}
}
// Write out voxel data as obj
saveVoxelsToObj(argv[2]);
}
delete g_voxelGrid;
}