nr-rect.cpp revision 36a048753a41b465ae130b361fb3b68c605e3e86
#define __NR_RECT_C__
/*
* Pixel buffer rendering library
*
* Authors:
* Lauris Kaplinski <lauris@kaplinski.com>
*
* This code is in public domain
*/
#include "nr-rect-l.h"
/**
* \param r0 Rectangle.
* \param r1 Another rectangle.
* \param d Filled in with the intersection of r0 and r1.
* \return d.
*/
NRRectL *nr_rect_l_intersect(NRRectL *d, const NRRectL *r0, const NRRectL *r1)
{
NR::ICoord t;
t = std::max(r0->x0, r1->x0);
d->x1 = std::min(r0->x1, r1->x1);
d->x0 = t;
t = std::max(r0->y0, r1->y0);
d->y1 = std::min(r0->y1, r1->y1);
d->y0 = t;
return d;
}
NRRect *
nr_rect_d_intersect (NRRect *d, const NRRect *r0, const NRRect *r1)
{
NR::Coord t;
t = MAX (r0->x0, r1->x0);
d->x1 = MIN (r0->x1, r1->x1);
d->x0 = t;
t = MAX (r0->y0, r1->y0);
d->y1 = MIN (r0->y1, r1->y1);
d->y0 = t;
return d;
}
NRRect *
nr_rect_d_union (NRRect *d, const NRRect *r0, const NRRect *r1)
{
if (NR_RECT_DFLS_TEST_EMPTY (r0)) {
if (NR_RECT_DFLS_TEST_EMPTY (r1)) {
nr_rect_d_set_empty (d);
} else {
*d = *r1;
}
} else {
if (NR_RECT_DFLS_TEST_EMPTY (r1)) {
*d = *r0;
} else {
NR::Coord t;
t = MIN (r0->x0, r1->x0);
d->x1 = MAX (r0->x1, r1->x1);
d->x0 = t;
t = MIN (r0->y0, r1->y0);
d->y1 = MAX (r0->y1, r1->y1);
d->y0 = t;
}
}
return d;
}
NRRectL *
nr_rect_l_union (NRRectL *d, const NRRectL *r0, const NRRectL *r1)
{
if (NR_RECT_DFLS_TEST_EMPTY (r0)) {
if (NR_RECT_DFLS_TEST_EMPTY (r1)) {
nr_rect_l_set_empty (d);
} else {
*d = *r1;
}
} else {
if (NR_RECT_DFLS_TEST_EMPTY (r1)) {
*d = *r0;
} else {
NR::ICoord t;
t = MIN (r0->x0, r1->x0);
d->x1 = MAX (r0->x1, r1->x1);
d->x0 = t;
t = MIN (r0->y0, r1->y0);
d->y1 = MAX (r0->y1, r1->y1);
d->y0 = t;
}
}
return d;
}
NRRect *
nr_rect_union_pt(NRRect *dst, NR::Point const &p)
{
using NR::X;
using NR::Y;
return nr_rect_d_union_xy(dst, p[X], p[Y]);
}
NRRect *
nr_rect_d_union_xy (NRRect *d, NR::Coord x, NR::Coord y)
{
if ((d->x0 <= d->x1) && (d->y0 <= d->y1)) {
d->x0 = MIN (d->x0, x);
d->y0 = MIN (d->y0, y);
d->x1 = MAX (d->x1, x);
d->y1 = MAX (d->y1, y);
} else {
d->x0 = d->x1 = x;
d->y0 = d->y1 = y;
}
return d;
}
NRRect *
nr_rect_d_matrix_transform(NRRect *d, NRRect const *const s, NR::Matrix const &m)
{
using NR::X;
using NR::Y;
if (nr_rect_d_test_empty(s)) {
nr_rect_d_set_empty(d);
} else {
NR::Point const c00(NR::Point(s->x0, s->y0) * m);
NR::Point const c01(NR::Point(s->x0, s->y1) * m);
NR::Point const c10(NR::Point(s->x1, s->y0) * m);
NR::Point const c11(NR::Point(s->x1, s->y1) * m);
d->x0 = std::min(std::min(c00[X], c01[X]),
std::min(c10[X], c11[X]));
d->y0 = std::min(std::min(c00[Y], c01[Y]),
std::min(c10[Y], c11[Y]));
d->x1 = std::max(std::max(c00[X], c01[X]),
std::max(c10[X], c11[X]));
d->y1 = std::max(std::max(c00[Y], c01[Y]),
std::max(c10[Y], c11[Y]));
}
return d;
}
NRRect *
nr_rect_d_matrix_transform(NRRect *d, NRRect const *s, NRMatrix const *m)
{
return nr_rect_d_matrix_transform(d, s, *m);
}
/** Enlarges the rectangle given amount of pixels to all directions */
NRRectL *
nr_rect_l_enlarge(NRRectL *d, int amount)
{
d->x0 -= amount;
d->y0 -= amount;
d->x1 += amount;
d->y1 += amount;
return d;
}
namespace NR {
Rect::Rect(const Point &p0, const Point &p1)
: _min(MIN(p0[X], p1[X]), MIN(p0[Y], p1[Y])),
_max(MAX(p0[X], p1[X]), MAX(p0[Y], p1[Y])) {}
/** returns the four corners of the rectangle in the correct winding order */
Point Rect::corner(unsigned i) const {
switch (i % 4) {
case 0:
return _min;
case 1:
return Point(_max[X], _min[Y]);
case 2:
return _max;
default: /* i.e. 3 */
return Point(_min[X], _max[Y]);
}
}
/** returns the midpoint of this rectangle */
Point Rect::midpoint() const {
return ( _min + _max ) / 2;
}
/** returns a vector from topleft to bottom right. */
Point Rect::dimensions() const {
return _max - _min;
}
/** Translates the rectangle by p. */
void Rect::offset(Point p) {
_min += p;
_max += p;
}
/** Makes this rectangle large enough to include the point p. */
void Rect::expandTo(Point p) {
for ( int i=0 ; i < 2 ; i++ ) {
_min[i] = MIN(_min[i], p[i]);
_max[i] = MAX(_max[i], p[i]);
}
}
/** Returns the set of points shared by both rectangles. */
Maybe<Rect> Rect::intersection(const Rect &a, const Rect &b) {
Rect r;
for ( int i=0 ; i < 2 ; i++ ) {
r._min[i] = MAX(a._min[i], b._min[i]);
r._max[i] = MIN(a._max[i], b._max[i]);
if ( r._min[i] > r._max[i] ) {
return Nothing();
}
}
return r;
}
/** returns the smallest rectangle containing both rectangles */
Rect Rect::union_bounds(const Rect &a, const Rect &b) {
Rect r;
for ( int i=0; i < 2 ; i++ ) {
r._min[i] = MIN(a._min[i], b._min[i]);
r._max[i] = MAX(a._max[i], b._max[i]);
}
return r;
}
} // namespace NR
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :