/* Combine two transformations. out can be one of the ins.
*/
int
im__transform_add( const Transformation *in1, const Transformation *in2,
Transformation *out )
{
out->a = in1->a * in2->a + in1->c * in2->b;
out->b = in1->b * in2->a + in1->d * in2->b;
out->c = in1->a * in2->c + in1->c * in2->d;
out->d = in1->b * in2->c + in1->d * in2->d;
out->dx = in1->dx * in2->a + in1->dy * in2->b + in2->dx;
out->dy = in1->dx * in2->c + in1->dy * in2->d + in2->dy;
if( im__transform_calc_inverse( out ) )
return( -1 );
return( 0 );
}
/* Init a Transform.
*/
void
im__transform_init( Transformation *trn )
{
trn->oarea.left = 0;
trn->oarea.top = 0;
trn->oarea.width = -1;
trn->oarea.height = -1;
trn->iarea.left = 0;
trn->iarea.top = 0;
trn->iarea.width = -1;
trn->iarea.height = -1;
trn->a = 1.0; /* Identity transform */
trn->b = 0.0;
trn->c = 0.0;
trn->d = 1.0;
trn->dx = 0.0;
trn->dy = 0.0;
(void) im__transform_calc_inverse( trn );
}
/* Like im_similarity(), but return the transform we generated.
*/
static int
apply_similarity( Transformation *trn, IMAGE *in, IMAGE *out,
double a, double b, double dx, double dy )
{
trn->iarea.left = 0;
trn->iarea.top = 0;
trn->iarea.width = in->Xsize;
trn->iarea.height = in->Ysize;
trn->a = a;
trn->b = -b;
trn->c = b;
trn->d = a;
trn->dx = dx;
trn->dy = dy;
im__transform_set_area( trn );
if( im__transform_calc_inverse( trn ) )
return( -1 );
if( im__affine( in, out, trn ) )
return( -1 );
return( 0 );
}
static int
affinei( IMAGE *in, IMAGE *out,
VipsInterpolate *interpolate, Transformation *trn )
{
Affine *affine;
double edge;
/* Make output image.
*/
if( im_piocheck( in, out ) )
return( -1 );
if( im_cp_desc( out, in ) )
return( -1 );
/* Need a copy of the params for the lifetime of out.
*/
if( !(affine = IM_NEW( out, Affine )) )
return( -1 );
affine->interpolate = NULL;
if( im_add_close_callback( out,
(im_callback_fn) affine_free, affine, NULL ) )
return( -1 );
affine->in = in;
affine->out = out;
affine->interpolate = interpolate;
g_object_ref( interpolate );
affine->trn = *trn;
if( im__transform_calc_inverse( &affine->trn ) )
return( -1 );
out->Xsize = affine->trn.oarea.width;
out->Ysize = affine->trn.oarea.height;
/* Normally SMALLTILE ... except if this is a size up/down affine.
*/
if( affine->trn.b == 0.0 && affine->trn.c == 0.0 ) {
if( im_demand_hint( out, IM_FATSTRIP, in, NULL ) )
return( -1 );
}
else {
if( im_demand_hint( out, IM_SMALLTILE, in, NULL ) )
return( -1 );
}
/* Check for coordinate overflow ... we want to be able to hold the
* output space inside INT_MAX / TRANSFORM_SCALE.
*/
edge = INT_MAX / VIPS_TRANSFORM_SCALE;
if( affine->trn.oarea.left < -edge || affine->trn.oarea.top < -edge ||
IM_RECT_RIGHT( &affine->trn.oarea ) > edge ||
IM_RECT_BOTTOM( &affine->trn.oarea ) > edge ) {
im_error( "im_affinei",
"%s", _( "output coordinates out of range" ) );
return( -1 );
}
/* Generate!
*/
if( im_generate( out,
im_start_one, affinei_gen, im_stop_one, in, affine ) )
return( -1 );
return( 0 );
}
