/*
Compute the exact integration of the mipmap \a M within the ball of
radius r and center (x0,y0,z0).
The method is a simple scanning at the finest scale.
*/
Value computeExact( MipMap* M, int x0, int y0, int z0, Value r )
{
Image* img = MipMap_get_image( M, M->max_lvl );
int minx = x0 - (int) ceil( r );
int miny = y0 - (int) ceil( r );
int minz = z0 - (int) ceil( r );
int maxx = x0 + (int) ceil( r );
int maxy = y0 + (int) ceil( r );
int maxz = z0 + (int) ceil( r );
minx = minx <= 0 ? 0 : minx;
miny = miny <= 0 ? 0 : miny;
minz = minz <= 0 ? 0 : minz;
maxx = maxx >= img->size ? img->size-1 : maxx;
maxy = maxy >= img->size ? img->size-1 : maxy;
maxz = maxz >= img->size ? img->size-1 : maxz;
Value r2 = r*r;
Value acc = (Value) 0;
for ( int z = minz; z <= maxz; ++z )
for ( int y = miny; y <= maxy; ++y )
for ( int x = minx; x <= maxx; ++x )
{
if ( distance2( x0, y0, z0, x, y, z ) <= r2 )
{
acc += Image_get( img, x, y, z );
nb_access_exact += 1;
}
nb_iteration_exact += 1;
}
return acc;
}
void MipMap_init_from_image_and_functor( MipMap* mipmap, Image* img, VoxelFunctor f )
{
assert( ( img->lvl >= 0 ) && ( img->lvl <= LVL ) );
mipmap->max_lvl = img->lvl;
for ( int k = img->lvl; k >= 0; --k )
{
Image_init( &mipmap->hierarchy[ k ], k );
}
// Copy image with functor (a moment).
Image* src = img;
Image* dst = MipMap_get_image( mipmap, img->lvl );
for ( int z = 0; z < src->size; ++z )
for ( int y = 0; y < src->size; ++y )
for ( int x = 0; x < src->size; ++x )
Image_set( dst, x, y, z, f( Image_get( src, x, y, z ), x, y, z ) );
// Compute hierarchy
for ( int k = img->lvl - 1; k >= 0; --k )
{
Image* src = MipMap_get_image( mipmap, k+1 );
Image* dst = MipMap_get_image( mipmap, k );
for ( int z = 0; z < dst->size; ++z )
for ( int y = 0; y < dst->size; ++y )
for ( int x = 0; x < dst->size; ++x )
{
Value f = Image_get( src, 2*x, 2*y, 2*z );
f += Image_get( src, 2*x+1, 2*y, 2*z );
f += Image_get( src, 2*x, 2*y+1, 2*z );
f += Image_get( src, 2*x+1, 2*y+1, 2*z );
f += Image_get( src, 2*x, 2*y, 2*z+1 );
f += Image_get( src, 2*x+1, 2*y, 2*z+1 );
f += Image_get( src, 2*x, 2*y+1, 2*z+1 );
f += Image_get( src, 2*x+1, 2*y+1, 2*z+1 );
Image_set( dst, x, y, z, f / (Value) 8 );
}
}
}
Distribution* Image_getDistribution(Image* img)
{
Distribution* r = Distribution_init();
double quadW = ((float)img->w)/FIELD_SIZE;
double quadH = ((float)img->h)/FIELD_SIZE;
double f = 1.0/(quadW*quadH);
int i, j;
for(i = 0; i < img->h; i++)
{
for(j = 0; j < img->w; j++)
{
r->data[Distribution_getIndex((int)(j/quadW), (int)(i/quadH))]
+= Image_get(img, j, i);
}
}
for(i = 0; i < FIELD_SIZE; i++)
{
for(j = 0; j < FIELD_SIZE; j++)
{
r->data[Distribution_getIndex(j, i)] *= f;
}
}
return r;
}