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// Copyright (C) 1999-2017
// Smithsonian Astrophysical Observatory, Cambridge, MA, USA
// For conditions of distribution and use, see copyright notice in "copyright"
#include <tk.h>
#include "vector.h"
#include "vector3d.h"
#include "fuzzy.h"
// Vector::manip
int Vector::separator = ios_base::xalloc();
int Vector::unit = ios_base::xalloc();
Vector::Vector(const Vector3d& a)
{
v[0]=a.v[0];
v[1]=a.v[1];
v[2]=1;
}
Vector& Vector::operator=(const Vector3d& a)
{
v[0]=a.v[0];
v[1]=a.v[1];
v[2]=1;
return *this;
}
Vector& Vector::clip(const BBox& bb)
{
// restrict vector by bbox
Vector ll(bb.ll);
Vector ur(bb.ur);
if (v[0]<ll[0])
v[0]=ll[0];
if (v[0]>ur[0])
v[0]=ur[0];
if (v[1]<ll[1])
v[1]=ll[1];
if (v[1]>ur[1])
v[1]=ur[1];
return *this;
}
Vector Vector::TkCanvasPs(void* canvas)
{
return Vector(v[0], Tk_CanvasPsY((Tk_Canvas)canvas, v[1]));
}
ostream& operator<<(ostream& os, const Vector& v)
{
unsigned char sep = (unsigned char)os.iword(Vector::separator);
if (!sep)
sep = ' ';
unsigned char unit = (unsigned char)os.iword(Vector::unit);
if (!unit)
os << v.v[0] << sep << v.v[1];
else
os << v.v[0] << unit << sep << v.v[1] << unit;
// reset unit
os.iword(Vector::unit) = '\0';
return os;
}
istream& operator>>(istream& s, Vector& v)
{
s >> v.v[0] >> v.v[1];
return s;
}
// Vertex
ostream& operator<<(ostream& os, const Vertex& v)
{
os << v.vector;
return os;
}
// Matrix
Matrix& Matrix::operator*=(const Matrix& a)
{
Matrix r;
for (int i=0; i<3; i++)
for (int j=0; j<3; j++)
r.m[i][j] =
m[i][0]*a.m[0][j] +
m[i][1]*a.m[1][j] +
m[i][2]*a.m[2][j];
return *this=r;
}
Matrix Matrix::invert()
{
Matrix cc = this->cofactor();
Matrix aa = cc.adjoint();
double dd = m[0][0]*aa.m[0][0] + m[0][1]*aa.m[1][0] + m[0][2]*aa.m[2][0];
Matrix rr;
for (int ii=0; ii<3; ii++ )
for (int jj=0; jj<3; jj++)
rr.m[ii][jj] = aa.m[ii][jj]/dd;
return rr;
}
Matrix Matrix::cofactor()
{
Matrix rr;
rr.m[0][0] = +(m[1][1]*m[2][2]-m[1][2]*m[2][1]);
rr.m[0][1] = -(m[1][0]*m[2][2]-m[1][2]*m[2][0]);
rr.m[0][2] = +(m[1][0]*m[2][1]-m[1][1]*m[2][0]);
rr.m[1][0] = -(m[0][1]*m[2][2]-m[0][2]*m[2][1]);
rr.m[1][1] = +(m[0][0]*m[2][2]-m[0][2]*m[2][0]);
rr.m[1][2] = -(m[0][0]*m[2][1]-m[0][1]*m[2][0]);
rr.m[2][0] = +(m[0][1]*m[1][2]-m[0][2]*m[1][1]);
rr.m[2][1] = -(m[0][0]*m[1][2]-m[0][2]*m[1][0]);
rr.m[2][2] = +(m[0][0]*m[1][1]-m[0][1]*m[1][0]);
return rr;
}
double Matrix::det()
{
return
+ m[0][0]*(m[1][1]*m[2][2]-m[1][2]*m[2][1])
- m[0][1]*(m[1][0]*m[2][2]-m[1][2]*m[2][0])
+ m[0][2]*(m[1][0]*m[2][1]-m[1][1]*m[2][0]);
}
Matrix Matrix::adjoint()
{
Matrix rr;
for (int ii=0; ii<3; ii++)
for (int jj=0; jj<3; jj++)
rr.m[jj][ii] = m[ii][jj];
return rr;
}
ostream& operator<<(ostream& os, const Matrix& m)
{
os << ' ';
for (int i=0; i<3; i++)
for (int j=0; j<2; j++)
os << m.m[i][j] << ' ';
return os;
}
istream& operator>>(istream& s, Matrix& m)
{
for (int i=0; i<3; i++ )
for (int j=0; j<2; j++)
s >> m.m[i][j];
return s;
}
// Translate
ostream& operator<<(ostream& os, const Translate& m)
{
os << ' ' << m.m[2][0] << ' ' << m.m[2][1] << ' ';
return os;
}
istream& operator>>(istream& s, Translate& m)
{
s >> m.m[2][0] >> m.m[2][1];
return s;
}
// Scale
ostream& operator<<(ostream& os, const Scale& m)
{
os << ' ' << m.m[0][0] << ' ' << m.m[1][1] << ' ';
return os;
}
istream& operator>>(istream& s, Scale& m)
{
s >> m.m[0][0] >> m.m[1][1];
return s;
}
// Rotate
Rotate::Rotate(double a) : Matrix()
{
// note: signs reverse for X-Windows (origin is upper left)
m[0][0] = cos(a);
m[0][1] = -sin(a);
m[1][0] = sin(a);
m[1][1] = cos(a);
// this fixes a problem with numbers too small and tring to invert the matrix
tzero(&m[0][0]);
tzero(&m[0][1]);
tzero(&m[1][0]);
tzero(&m[1][1]);
}
ostream& operator<<(ostream& os, const Rotate& m)
{
os << ' ' << m.m[0][0] << ' ' << m.m[0][1]
<< ' ' << m.m[1][0] << ' ' << m.m[1][1] << ' ';
return os;
}
istream& operator>>(istream& s, Rotate& m)
{
s >> m.m[0][0] >> m.m[0][1] >> m.m[1][0] >> m.m[1][1];
return s;
}
// BBox
BBox::BBox(double a, double b, double c, double d)
{
// we want a 'positive' box
ll.v[0] = a < c ? a : c;
ll.v[1] = b < d ? b : d;
ur.v[0] = a < c ? c : a;
ur.v[1] = b < d ? d : b;
}
BBox::BBox(const Vector& l, const Vector& h)
{
// we want a 'positive' box
ll.v[0] = l.v[0] < h.v[0] ? l.v[0] : h.v[0];
ll.v[1] = l.v[1] < h.v[1] ? l.v[1] : h.v[1];
ur.v[0] = l.v[0] < h.v[0] ? h.v[0] : l.v[0];
ur.v[1] = l.v[1] < h.v[1] ? h.v[1] : l.v[1];
}
int BBox::isIn(const Vector& v) const
{
return !(v.v[0] < ll.v[0] || v.v[1] < ll.v[1] ||
v.v[0] > ur.v[0] || v.v[1] > ur.v[1]);
}
int BBox::isIn(const BBox& bb) const
{
// return 0 if outside, > 0 if intersection
// = 4 if inside
BBox b = bb;
return isIn(b.ll) + isIn(b.ur) + isIn(b.ul()) + isIn(b.lr());
}
BBox& BBox::bound(const Vector& v)
{
if (v.v[0] < ll[0])
ll[0] = v.v[0];
if (v.v[1] < ll[1])
ll[1] = v.v[1];
if (v.v[0] > ur[0])
ur[0] = v.v[0];
if (v.v[1] > ur[1])
ur[1] = v.v[1];
return *this;
}
BBox& BBox::bound(BBox b)
{
this->bound(b.ll);
this->bound(b.lr());
this->bound(b.ur);
this->bound(b.ul());
return *this;
}
BBox intersect(const BBox& a, const BBox& b)
{
// test for obvious
int ab = a.isIn(b);
int ba = b.isIn(a);
// no intersection?
if (ab==0 && ba == 0) {
// maybe they are just crossed, check the centers
int abc = a.isIn(((BBox&)b).center());
int bac = b.isIn(((BBox&)a).center());
if (abc==0 && bac==0)
return BBox();
}
if (ab == 4) // b is inside a
return b;
if (ba == 4) // a is inside b
return a;
// else, there seems to be some overlap
BBox r;
r.ll.v[0] = (a.ll.v[0] > b.ll.v[0]) ? a.ll.v[0] : b.ll.v[0];
r.ll.v[1] = (a.ll.v[1] > b.ll.v[1]) ? a.ll.v[1] : b.ll.v[1];
r.ur.v[0] = (a.ur.v[0] < b.ur.v[0]) ? a.ur.v[0] : b.ur.v[0];
r.ur.v[1] = (a.ur.v[1] < b.ur.v[1]) ? a.ur.v[1] : b.ur.v[1];
return r;
}
ostream& operator<<(ostream& os, const BBox& b)
{
os << b.ll << ' ' << b.ur;
return os;
}
// Cohen–Sutherland clipping algorithm
// bounded diagonally by (0,0), and (width, height)
const int INSIDE = 0; // 0000
const int LEFT = 1; // 0001
const int RIGHT = 2; // 0010
const int BOTTOM = 4; // 0100
const int TOP = 8; // 1000
static int calcOutCode(Vector vv, int width, int height)
{
int code = INSIDE;
if (vv[0] < 0) // to the left of clip window
code |= LEFT;
else if (vv[0] > width) // to the right of clip window
code |= RIGHT;
if (vv[1] < 0) // below the clip window
code |= BOTTOM;
else if (vv[1] > height) // above the clip window
code |= TOP;
return code;
}
int clip(Vector* v0, Vector* v1, int width, int height)
{
int outcode0 = calcOutCode(*v0, width, height);
int outcode1 = calcOutCode(*v1, width, height);
int accept = false;
while (true) {
if (!(outcode0 | outcode1)) {
// Bitwise OR is 0. Trivially accept and get out of loop
accept = true;
break;
}
else if (outcode0 & outcode1) {
// Bitwise AND is not 0. Trivially reject and get out of loop
break;
}
else {
// At least one endpoint is outside the clip rectangle; pick it.
int outcodeOut = outcode0 ? outcode0 : outcode1;
// Now find the intersection point
// y = y0 + slope * (x - x0)
// x = x0 + (1 / slope) * (y - y0)
double x, y;
if (outcodeOut & TOP) {
// point is above the clip rectangle
x = (*v0)[0] + ((*v1)[0]-(*v0)[0]) *
(height-(*v0)[1]) / ((*v1)[1]-(*v0)[1]);
y = height;
}
else if (outcodeOut & BOTTOM) {
// point is below the clip rectangle
x = (*v0)[0] + ((*v1)[0]-(*v0)[0]) *
(0-(*v0)[1]) / ((*v1)[1]-(*v0)[1]);
y = 0;
}
else if (outcodeOut & RIGHT) {
// point is to the right of clip rectangle
y = (*v0)[1] + ((*v1)[1]-(*v0)[1]) *
(width-(*v0)[0]) / ((*v1)[0]-(*v0)[0]);
x = width;
}
else if (outcodeOut & LEFT) {
// point is to the left of clip rectangle
y = (*v0)[1] + ((*v1)[1]-(*v0)[1]) *
(0-(*v0)[0]) / ((*v1)[0]-(*v0)[0]);
x = 0;
}
// Now we move outside point to intersection point to clip
// and get ready for next pass.
if (outcodeOut == outcode0) {
(*v0)[0] = x;
(*v0)[1] = y;
outcode0 = calcOutCode(*v0, width, height);
}
else {
(*v1)[0] = x;
(*v1)[1] = y;
outcode1 = calcOutCode(*v1, width, height);
}
}
}
return accept;
}
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