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#include "fitz.h"
#define MAX4(a,b,c,d) MAX(MAX(a,b), MAX(c,d))
#define MIN4(a,b,c,d) MIN(MIN(a,b), MIN(c,d))
/* Matrices, points and affine transformations */
const fz_matrix fz_identity = { 1, 0, 0, 1, 0, 0 };
fz_matrix
fz_concat(fz_matrix one, fz_matrix two)
{
fz_matrix dst;
dst.a = one.a * two.a + one.b * two.c;
dst.b = one.a * two.b + one.b * two.d;
dst.c = one.c * two.a + one.d * two.c;
dst.d = one.c * two.b + one.d * two.d;
dst.e = one.e * two.a + one.f * two.c + two.e;
dst.f = one.e * two.b + one.f * two.d + two.f;
return dst;
}
fz_matrix
fz_scale(float sx, float sy)
{
fz_matrix m;
m.a = sx; m.b = 0;
m.c = 0; m.d = sy;
m.e = 0; m.f = 0;
return m;
}
fz_matrix
fz_rotate(float theta)
{
fz_matrix m;
float s;
float c;
while (theta < 0)
theta += 360;
while (theta >= 360)
theta -= 360;
if (fabsf(0 - theta) < FLT_EPSILON)
{
s = 0;
c = 1;
}
else if (fabsf(90.0f - theta) < FLT_EPSILON)
{
s = 1;
c = 0;
}
else if (fabsf(180.0f - theta) < FLT_EPSILON)
{
s = 0;
c = -1;
}
else if (fabsf(270.0f - theta) < FLT_EPSILON)
{
s = -1;
c = 0;
}
else
{
s = sinf(theta * (float)M_PI / 180);
c = cosf(theta * (float)M_PI / 180);
}
m.a = c; m.b = s;
m.c = -s; m.d = c;
m.e = 0; m.f = 0;
return m;
}
fz_matrix
fz_translate(float tx, float ty)
{
fz_matrix m;
m.a = 1; m.b = 0;
m.c = 0; m.d = 1;
m.e = tx; m.f = ty;
return m;
}
fz_matrix
fz_invert_matrix(fz_matrix src)
{
fz_matrix dst;
float rdet = 1 / (src.a * src.d - src.b * src.c);
dst.a = src.d * rdet;
dst.b = -src.b * rdet;
dst.c = -src.c * rdet;
dst.d = src.a * rdet;
dst.e = -src.e * dst.a - src.f * dst.c;
dst.f = -src.e * dst.b - src.f * dst.d;
return dst;
}
int
fz_is_rectilinear(fz_matrix m)
{
return (fabsf(m.b) < FLT_EPSILON && fabsf(m.c) < FLT_EPSILON) ||
(fabsf(m.a) < FLT_EPSILON && fabsf(m.d) < FLT_EPSILON);
}
float
fz_matrix_expansion(fz_matrix m)
{
return sqrtf(fabsf(m.a * m.d - m.b * m.c));
}
fz_point
fz_transform_point(fz_matrix m, fz_point p)
{
fz_point t;
t.x = p.x * m.a + p.y * m.c + m.e;
t.y = p.x * m.b + p.y * m.d + m.f;
return t;
}
fz_point
fz_transform_vector(fz_matrix m, fz_point p)
{
fz_point t;
t.x = p.x * m.a + p.y * m.c;
t.y = p.x * m.b + p.y * m.d;
return t;
}
/* Rectangles and bounding boxes */
const fz_rect fz_infinite_rect = { 1, 1, -1, -1 };
const fz_rect fz_empty_rect = { 0, 0, 0, 0 };
const fz_rect fz_unit_rect = { 0, 0, 1, 1 };
const fz_bbox fz_infinite_bbox = { 1, 1, -1, -1 };
const fz_bbox fz_empty_bbox = { 0, 0, 0, 0 };
const fz_bbox fz_unit_bbox = { 0, 0, 1, 1 };
fz_bbox
fz_round_rect(fz_rect f)
{
fz_bbox i;
i.x0 = floorf(f.x0 + 0.001f); /* adjust by 0.001 to compensate for precision errors */
i.y0 = floorf(f.y0 + 0.001f);
i.x1 = ceilf(f.x1 - 0.001f);
i.y1 = ceilf(f.y1 - 0.001f);
return i;
}
fz_bbox
fz_intersect_bbox(fz_bbox a, fz_bbox b)
{
fz_bbox r;
if (fz_is_infinite_rect(a)) return b;
if (fz_is_infinite_rect(b)) return a;
if (fz_is_empty_rect(a)) return fz_empty_bbox;
if (fz_is_empty_rect(b)) return fz_empty_bbox;
r.x0 = MAX(a.x0, b.x0);
r.y0 = MAX(a.y0, b.y0);
r.x1 = MIN(a.x1, b.x1);
r.y1 = MIN(a.y1, b.y1);
return (r.x1 < r.x0 || r.y1 < r.y0) ? fz_empty_bbox : r;
}
fz_bbox
fz_union_bbox(fz_bbox a, fz_bbox b)
{
fz_bbox r;
if (fz_is_infinite_rect(a)) return a;
if (fz_is_infinite_rect(b)) return b;
if (fz_is_empty_rect(a)) return b;
if (fz_is_empty_rect(b)) return a;
r.x0 = MIN(a.x0, b.x0);
r.y0 = MIN(a.y0, b.y0);
r.x1 = MAX(a.x1, b.x1);
r.y1 = MAX(a.y1, b.y1);
return r;
}
fz_rect
fz_transform_rect(fz_matrix m, fz_rect r)
{
fz_point s, t, u, v;
if (fz_is_infinite_rect(r))
return r;
s.x = r.x0; s.y = r.y0;
t.x = r.x0; t.y = r.y1;
u.x = r.x1; u.y = r.y1;
v.x = r.x1; v.y = r.y0;
s = fz_transform_point(m, s);
t = fz_transform_point(m, t);
u = fz_transform_point(m, u);
v = fz_transform_point(m, v);
r.x0 = MIN4(s.x, t.x, u.x, v.x);
r.y0 = MIN4(s.y, t.y, u.y, v.y);
r.x1 = MAX4(s.x, t.x, u.x, v.x);
r.y1 = MAX4(s.y, t.y, u.y, v.y);
return r;
}
fz_bbox
fz_transform_bbox(fz_matrix m, fz_bbox b)
{
fz_point s, t, u, v;
if (fz_is_infinite_bbox(b))
return b;
s.x = b.x0; s.y = b.y0;
t.x = b.x0; t.y = b.y1;
u.x = b.x1; u.y = b.y1;
v.x = b.x1; v.y = b.y0;
s = fz_transform_point(m, s);
t = fz_transform_point(m, t);
u = fz_transform_point(m, u);
v = fz_transform_point(m, v);
b.x0 = MIN4(s.x, t.x, u.x, v.x);
b.y0 = MIN4(s.y, t.y, u.y, v.y);
b.x1 = MAX4(s.x, t.x, u.x, v.x);
b.y1 = MAX4(s.y, t.y, u.y, v.y);
return b;
}
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