void spherify(Solid* s) {
unsigned n = s->nVerts;
Vec3 centroid = { 0,0,0 };
unsigned i;
for(i=0;i<n;++i) {
vec3Add(centroid,centroid,s->verts[i].loc);
}
vec3Mult(centroid,centroid,1.0/n);
Vec3* diffs = malloc(n*sizeof(Vec3));
float* dists = malloc(n*sizeof(float));
float maxR = 0;
for(i=0;i<n;++i) {
vec3Sub(diffs[i],s->verts[i].loc,centroid);
float r = vec3Mag(diffs[i]);
dists[i] = r;
if(r > maxR) {
maxR = r;
}
}
for(i=0;i<n;++i) {
vec3Mult(diffs[i],diffs[i],1.0/dists[i]);
vec3Copy(s->verts[i].normal,diffs[i]);
vec3Mult(diffs[i],diffs[i],maxR);
vec3Add(s->verts[i].loc,centroid,diffs[i]);
}
free(dists);
free(diffs);
}
static void applyForces(struct particle_system *ps, struct particle *p)
{
int i = 0;
vec3 force;
vec3 dir;
float m, d, s;
vec3Copy(p->dir, p->acc);
do {
switch(ps->forces[i].type) {
case PARTICLE_FORCE_DIRECTIONAL:
vec3Copy(ps->forces[i].dir, force);
break;
case PARTICLE_FORCE_FLUID:
s = vec3Mag(p->acc);
vec3Copy(p->acc, force);
vec3Normalize(force, force);
vec3Mul(force, -ps->forces[i].value*s*s, force);
break;
case PARTICLE_FORCE_ATTRACTION:
vec3Sub(ps->forces[i].loc, p->loc, dir);
d = vec3Mag(dir);
vec3Normalize(dir, dir);
m = 0.00001*ps->forces[i].value*p->mass / (d*d);
vec3Mul(dir, m, force);
break;
}
vec3Add(p->acc, force, p->acc);
} while(++i < ps->nbforces);
vec3Div(p->acc, p->mass, p->acc);
vec3Add(p->vel, p->acc, p->vel);
vec3Add(p->loc, p->vel, p->loc);
}
void Prop::tick(float dt)
{
if (propModel)
{
vec3Add(&propModel->position, &propModel->position, &velocity);
}
}
// Inverse edge length weighted method. As described in Real-time rendering (3rd ed.) p.546.
// Ref: Max, N. L., (1999) 'Weights for computing vertex normals from facet normals'
// in Journal of grahics tools, vol.4, no.2, pp.1-6.
static GLfloat* meshGenerateNormals(int num_verts, int num_elems, const GLfloat *verts, const GLushort *elems)
{
GLfloat *norms = (GLfloat*) calloc(3*num_verts, sizeof(GLfloat));
GLfloat e1[3], e2[3], no[3];
for (int i = 0; i < num_elems; i += 3) {
for (int j = 0; j < 3; ++j) {
int a = 3*elems[i+j];
int b = 3*elems[i+((j+1)%3)];
int c = 3*elems[i+((j+2)%3)];
vec3Sub(e1, &verts[c], &verts[b]);
vec3Sub(e2, &verts[a], &verts[b]);
vec3Cross(no, e1, e2);
double d = vec3Length2(e1) * vec3Length2(e2);
vec3DivScalar(no, no, d);
vec3Add(&norms[b], &norms[b], no);
}
}
for (int i = 0; i < 3*num_verts; i += 3) {
vec3Normalize(&norms[i], &norms[i]);
}
return norms;
}
double vec3ClosestOnSegment(GLfloat *result, const GLfloat *p, const GLfloat *a, const GLfloat *b)
{
GLfloat pa[3], ba[3];
vec3Sub(pa, p, a);
vec3Sub(ba, b, a);
double dotbaba = vec3Length2(ba);
double t = 0;
if (dotbaba != 0) {
t = vec3Dot(pa, ba) / dotbaba;
if (t < 0) t = 0;
else if (t > 1) t = 1;
}
vec3MulScalar(ba, ba, t);
vec3Add(result, a, ba);
return t;
}
int main(int argc, char* argv[]){
if(argc != 5){
printf("%s",HELP_MESSAGE);
return -1;
}
const int width = atoi(argv[2]);
const int height = atoi(argv[3]);
const int maxIterations = atoi(argv[4]);
if(width <= 0 || height <= 0){
printf("%s",BAD_WIDTH_HEIGHT_OR_MAX_ITERATIONS);
return -1;
}
FILE* file = fopen("test.ppm","wb");
if(file == NULL){
printf(FAILED_TO_CREATE_FILE);
return -1;
}
createFileHeader(file,width,height);
Vector3 direction;
direction = (Vector3){.x=0.5,.y=0.5,.z=1};
Vector3 from;
from = (Vector3){.x=-100,.y=-100,.z=-100};
int x = 0;
int y = 0;
int sampleRate = height/10;
int loadCount = 0;
for(y = 0; y<height; y++){
fprintf(file," ");
for(x = 0; x<width; x++){
Vector3 offset;
offset = (Vector3){.x = x, .y = y, .z = 0};
int value = (int)rayMarch(vec3Add(from,offset),direction,maxIterations);
fprintf(file,"%d %d %d ",value,value,value);
}
fprintf(file,"\n");
if(y % sampleRate == 0){
printf("\r%i\%% done",loadCount*10);
loadCount++;
}
}
fclose(file);
return 0;
}
void update(float _deltaTime)
{
if (m_mouseDown)
{
int32_t deltaX = m_mouseNow.m_mx - m_mouseLast.m_mx;
int32_t deltaY = m_mouseNow.m_my - m_mouseLast.m_my;
m_horizontalAngle += m_mouseSpeed * float(deltaX);
m_verticalAngle -= m_mouseSpeed * float(deltaY);
m_mouseLast.m_mx = m_mouseNow.m_mx;
m_mouseLast.m_my = m_mouseNow.m_my;
}
float direction[3] =
{
cosf(m_verticalAngle) * sinf(m_horizontalAngle),
sinf(m_verticalAngle),
cosf(m_verticalAngle) * cosf(m_horizontalAngle),
};
float right[3] =
{
sinf(m_horizontalAngle - float(M_PI)/2.0f),
0,
cosf(m_horizontalAngle - float(M_PI)/2.0f),
};
if (m_keys & CAMERA_KEY_UP)
{
// m_eye += direction * _deltaTime * m_moveSpeed
float tmpRhs[3];
float tmpPos[3];
memcpy(tmpPos, m_eye, sizeof(float)*3);
vec3Mul(tmpRhs, direction, _deltaTime * m_moveSpeed);
vec3Add(m_eye, tmpPos, tmpRhs);
setKeyState(CAMERA_KEY_UP, false);
}
if (m_keys & CAMERA_KEY_DOWN)
{
// m_eye -= direction * _deltaTime * m_moveSpeed
float tmpRhs[3];
float tmpPos[3];
memcpy(tmpPos, m_eye, sizeof(float)*3);
vec3Mul(tmpRhs, direction, _deltaTime * m_moveSpeed);
vec3Sub(m_eye, tmpPos, tmpRhs);
setKeyState(CAMERA_KEY_DOWN, false);
}
if (m_keys & CAMERA_KEY_LEFT)
{
// m_eye += right * _deltaTime * m_moveSpeed
float tmpRhs[3];
float tmpPos[3];
memcpy(tmpPos, m_eye, sizeof(float)*3);
vec3Mul(tmpRhs, right, _deltaTime * m_moveSpeed);
vec3Add(m_eye, tmpPos, tmpRhs);
setKeyState(CAMERA_KEY_LEFT, false);
}
if (m_keys & CAMERA_KEY_RIGHT)
{
// m_eye -= right * _deltaTime * m_moveSpeed
float tmpRhs[3];
float tmpPos[3];
memcpy(tmpPos, m_eye, sizeof(float)*3);
vec3Mul(tmpRhs, right, _deltaTime * m_moveSpeed);
vec3Sub(m_eye, tmpPos, tmpRhs);
setKeyState(CAMERA_KEY_RIGHT, false);
}
vec3Add(m_at, m_eye, direction);
vec3Cross(m_up, right, direction);
}