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authorTor Andersson <tor.andersson@artifex.com>2013-06-19 15:29:44 +0200
committerTor Andersson <tor.andersson@artifex.com>2013-06-20 16:45:35 +0200
commit0a927854a10e1e6b9770a81e2e1d9f3093631757 (patch)
tree3d65d820d9fdba2d0d394d99c36290c851b78ca0 /source/fitz/geometry.c
parent1ae8f19179c5f0f8c6352b3c7855465325d5449a (diff)
downloadmupdf-0a927854a10e1e6b9770a81e2e1d9f3093631757.tar.xz
Rearrange source files.
Diffstat (limited to 'source/fitz/geometry.c')
-rw-r--r--source/fitz/geometry.c483
1 files changed, 483 insertions, 0 deletions
diff --git a/source/fitz/geometry.c b/source/fitz/geometry.c
new file mode 100644
index 00000000..81450246
--- /dev/null
+++ b/source/fitz/geometry.c
@@ -0,0 +1,483 @@
+#include "mupdf/fitz.h"
+
+#define MAX4(a,b,c,d) fz_max(fz_max(a,b), fz_max(c,d))
+#define MIN4(a,b,c,d) fz_min(fz_min(a,b), fz_min(c,d))
+
+/* A useful macro to add with overflow detection and clamping.
+
+ We want to do "b = a + x", but to allow for overflow. Consider the
+ top bits, and the cases in which overflow occurs:
+
+ overflow a x b ~a^x a^b (~a^x)&(a^b)
+ no 0 0 0 1 0 0
+ yes 0 0 1 1 1 1
+ no 0 1 0 0 0 0
+ no 0 1 1 0 1 0
+ no 1 0 0 0 1 0
+ no 1 0 1 0 0 0
+ yes 1 1 0 1 1 1
+ no 1 1 1 1 0 0
+*/
+#define ADD_WITH_SAT(b,a,x) \
+ ((b) = (a) + (x), (b) = (((~(a)^(x))&((a)^(b))) < 0 ? ((x) < 0 ? INT_MIN : INT_MAX) : (b)))
+
+/* Matrices, points and affine transformations */
+
+const fz_matrix fz_identity = { 1, 0, 0, 1, 0, 0 };
+
+fz_matrix *
+fz_concat(fz_matrix *dst, const fz_matrix *one, const fz_matrix *two)
+{
+ fz_matrix dst2;
+ dst2.a = one->a * two->a + one->b * two->c;
+ dst2.b = one->a * two->b + one->b * two->d;
+ dst2.c = one->c * two->a + one->d * two->c;
+ dst2.d = one->c * two->b + one->d * two->d;
+ dst2.e = one->e * two->a + one->f * two->c + two->e;
+ dst2.f = one->e * two->b + one->f * two->d + two->f;
+ *dst = dst2;
+ return dst;
+}
+
+fz_matrix *
+fz_scale(fz_matrix *m, float sx, float sy)
+{
+ m->a = sx; m->b = 0;
+ m->c = 0; m->d = sy;
+ m->e = 0; m->f = 0;
+ return m;
+}
+
+fz_matrix *
+fz_pre_scale(fz_matrix *mat, float sx, float sy)
+{
+ mat->a *= sx;
+ mat->b *= sx;
+ mat->c *= sy;
+ mat->d *= sy;
+ return mat;
+}
+
+fz_matrix *
+fz_shear(fz_matrix *mat, float h, float v)
+{
+ mat->a = 1; mat->b = v;
+ mat->c = h; mat->d = 1;
+ mat->e = 0; mat->f = 0;
+ return mat;
+}
+
+fz_matrix *
+fz_pre_shear(fz_matrix *mat, float h, float v)
+{
+ float a = mat->a;
+ float b = mat->b;
+ mat->a += v * mat->c;
+ mat->b += v * mat->d;
+ mat->c += h * a;
+ mat->d += h * b;
+ return mat;
+}
+
+fz_matrix *
+fz_rotate(fz_matrix *m, float theta)
+{
+ 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_pre_rotate(fz_matrix *m, float theta)
+{
+ while (theta < 0)
+ theta += 360;
+ while (theta >= 360)
+ theta -= 360;
+
+ if (fabsf(0 - theta) < FLT_EPSILON)
+ {
+ /* Nothing to do */
+ }
+ else if (fabsf(90.0f - theta) < FLT_EPSILON)
+ {
+ float a = m->a;
+ float b = m->b;
+ m->a = m->c;
+ m->b = m->d;
+ m->c = -a;
+ m->d = -b;
+ }
+ else if (fabsf(180.0f - theta) < FLT_EPSILON)
+ {
+ m->a = -m->a;
+ m->b = -m->b;
+ m->c = -m->c;
+ m->d = -m->d;
+ }
+ else if (fabsf(270.0f - theta) < FLT_EPSILON)
+ {
+ float a = m->a;
+ float b = m->b;
+ m->a = -m->c;
+ m->b = -m->d;
+ m->c = a;
+ m->d = b;
+ }
+ else
+ {
+ float s = sinf(theta * (float)M_PI / 180);
+ float c = cosf(theta * (float)M_PI / 180);
+ float a = m->a;
+ float b = m->b;
+ m->a = c * a + s * m->c;
+ m->b = c * b + s * m->d;
+ m->c =-s * a + c * m->c;
+ m->d =-s * b + c * m->d;
+ }
+
+ return m;
+}
+
+fz_matrix *
+fz_translate(fz_matrix *m, float tx, float ty)
+{
+ m->a = 1; m->b = 0;
+ m->c = 0; m->d = 1;
+ m->e = tx; m->f = ty;
+ return m;
+}
+
+fz_matrix *
+fz_pre_translate(fz_matrix *mat, float tx, float ty)
+{
+ mat->e += tx * mat->a + ty * mat->c;
+ mat->f += tx * mat->b + ty * mat->d;
+ return mat;
+}
+
+fz_matrix *
+fz_invert_matrix(fz_matrix *dst, const fz_matrix *src)
+{
+ /* Be careful to cope with dst == src */
+ float a = src->a;
+ float det = a * src->d - src->b * src->c;
+ if (det < -FLT_EPSILON || det > FLT_EPSILON)
+ {
+ float rdet = 1 / det;
+ dst->a = src->d * rdet;
+ dst->b = -src->b * rdet;
+ dst->c = -src->c * rdet;
+ dst->d = a * rdet;
+ a = -src->e * dst->a - src->f * dst->c;
+ dst->f = -src->e * dst->b - src->f * dst->d;
+ dst->e = a;
+ }
+ else
+ *dst = *src;
+ return dst;
+}
+
+int
+fz_is_rectilinear(const 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(const fz_matrix *m)
+{
+ return sqrtf(fabsf(m->a * m->d - m->b * m->c));
+}
+
+float
+fz_matrix_max_expansion(const fz_matrix *m)
+{
+ float max = fabsf(m->a);
+ float x = fabsf(m->b);
+ if (max < x)
+ max = x;
+ x = fabsf(m->c);
+ if (max < x)
+ max = x;
+ x = fabsf(m->d);
+ if (max < x)
+ max = x;
+ return max;
+}
+
+fz_point *
+fz_transform_point(fz_point *restrict p, const fz_matrix *restrict m)
+{
+ float x = p->x;
+ p->x = x * m->a + p->y * m->c + m->e;
+ p->y = x * m->b + p->y * m->d + m->f;
+ return p;
+}
+
+fz_point *
+fz_transform_vector(fz_point *restrict p, const fz_matrix *restrict m)
+{
+ float x = p->x;
+ p->x = x * m->a + p->y * m->c;
+ p->y = x * m->b + p->y * m->d;
+ return p;
+}
+
+void
+fz_normalize_vector(fz_point *p)
+{
+ float len = p->x * p->x + p->y * p->y;
+ if (len != 0)
+ {
+ len = sqrtf(len);
+ p->x /= len;
+ p->y /= len;
+ }
+}
+
+/* Rectangles and bounding boxes */
+
+/* biggest and smallest integers that a float can represent perfectly (i.e. 24 bits) */
+#define MAX_SAFE_INT 16777216
+#define MIN_SAFE_INT -16777216
+
+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_irect fz_infinite_irect = { 1, 1, -1, -1 };
+const fz_irect fz_empty_irect = { 0, 0, 0, 0 };
+const fz_irect fz_unit_bbox = { 0, 0, 1, 1 };
+
+fz_irect *
+fz_irect_from_rect(fz_irect *restrict b, const fz_rect *restrict r)
+{
+ b->x0 = fz_clamp(floorf(r->x0), MIN_SAFE_INT, MAX_SAFE_INT);
+ b->y0 = fz_clamp(floorf(r->y0), MIN_SAFE_INT, MAX_SAFE_INT);
+ b->x1 = fz_clamp(ceilf(r->x1), MIN_SAFE_INT, MAX_SAFE_INT);
+ b->y1 = fz_clamp(ceilf(r->y1), MIN_SAFE_INT, MAX_SAFE_INT);
+ return b;
+}
+
+fz_rect *
+fz_rect_from_irect(fz_rect *restrict r, const fz_irect *restrict a)
+{
+ r->x0 = a->x0;
+ r->y0 = a->y0;
+ r->x1 = a->x1;
+ r->y1 = a->y1;
+ return r;
+}
+
+fz_irect *
+fz_round_rect(fz_irect * restrict b, const fz_rect *restrict r)
+{
+ int i;
+
+ i = floorf(r->x0 + 0.001);
+ b->x0 = fz_clamp(i, MIN_SAFE_INT, MAX_SAFE_INT);
+ i = floorf(r->y0 + 0.001);
+ b->y0 = fz_clamp(i, MIN_SAFE_INT, MAX_SAFE_INT);
+ i = ceilf(r->x1 - 0.001);
+ b->x1 = fz_clamp(i, MIN_SAFE_INT, MAX_SAFE_INT);
+ i = ceilf(r->y1 - 0.001);
+ b->y1 = fz_clamp(i, MIN_SAFE_INT, MAX_SAFE_INT);
+
+ return b;
+}
+
+fz_rect *
+fz_intersect_rect(fz_rect *restrict a, const fz_rect *restrict b)
+{
+ /* Check for empty box before infinite box */
+ if (fz_is_empty_rect(a)) return a;
+ if (fz_is_empty_rect(b)) {
+ *a = fz_empty_rect;
+ return a;
+ }
+ if (fz_is_infinite_rect(b)) return a;
+ if (fz_is_infinite_rect(a)) {
+ *a = *b;
+ return a;
+ }
+ if (a->x0 < b->x0)
+ a->x0 = b->x0;
+ if (a->y0 < b->y0)
+ a->y0 = b->y0;
+ if (a->x1 > b->x1)
+ a->x1 = b->x1;
+ if (a->y1 > b->y1)
+ a->y1 = b->y1;
+ if (a->x1 < a->x0 || a->y1 < a->y0)
+ *a = fz_empty_rect;
+ return a;
+}
+
+fz_irect *
+fz_intersect_irect(fz_irect *restrict a, const fz_irect *restrict b)
+{
+ /* Check for empty box before infinite box */
+ if (fz_is_empty_irect(a)) return a;
+ if (fz_is_empty_irect(b))
+ {
+ *a = fz_empty_irect;
+ return a;
+ }
+ if (fz_is_infinite_irect(b)) return a;
+ if (fz_is_infinite_irect(a))
+ {
+ *a = *b;
+ return a;
+ }
+ if (a->x0 < b->x0)
+ a->x0 = b->x0;
+ if (a->y0 < b->y0)
+ a->y0 = b->y0;
+ if (a->x1 > b->x1)
+ a->x1 = b->x1;
+ if (a->y1 > b->y1)
+ a->y1 = b->y1;
+ if (a->x1 < a->x0 || a->y1 < a->y0)
+ *a = fz_empty_irect;
+ return a;
+}
+
+fz_rect *
+fz_union_rect(fz_rect *restrict a, const fz_rect *restrict b)
+{
+ /* Check for empty box before infinite box */
+ if (fz_is_empty_rect(b)) return a;
+ if (fz_is_empty_rect(a)) {
+ *a = *b;
+ return a;
+ }
+ if (fz_is_infinite_rect(a)) return a;
+ if (fz_is_infinite_rect(b)) {
+ *a = *b;
+ return a;
+ }
+ if (a->x0 > b->x0)
+ a->x0 = b->x0;
+ if (a->y0 > b->y0)
+ a->y0 = b->y0;
+ if (a->x1 < b->x1)
+ a->x1 = b->x1;
+ if (a->y1 < b->y1)
+ a->y1 = b->y1;
+ return a;
+}
+
+fz_irect *
+fz_translate_irect(fz_irect *a, int xoff, int yoff)
+{
+ int t;
+
+ if (fz_is_empty_irect(a)) return a;
+ if (fz_is_infinite_irect(a)) return a;
+ a->x0 = ADD_WITH_SAT(t, a->x0, xoff);
+ a->y0 = ADD_WITH_SAT(t, a->y0, yoff);
+ a->x1 = ADD_WITH_SAT(t, a->x1, xoff);
+ a->y1 = ADD_WITH_SAT(t, a->y1, yoff);
+ return a;
+}
+
+fz_rect *
+fz_transform_rect(fz_rect *restrict r, const fz_matrix *restrict m)
+{
+ fz_point s, t, u, v;
+
+ if (fz_is_infinite_rect(r))
+ return r;
+
+ if (fabsf(m->b) < FLT_EPSILON && fabsf(m->c) < FLT_EPSILON)
+ {
+ if (m->a < 0)
+ {
+ float f = r->x0;
+ r->x0 = r->x1;
+ r->x1 = f;
+ }
+ if (m->d < 0)
+ {
+ float f = r->y0;
+ r->y0 = r->y1;
+ r->y1 = f;
+ }
+ fz_transform_point(fz_rect_min(r), m);
+ fz_transform_point(fz_rect_max(r), m);
+ 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;
+ fz_transform_point(&s, m);
+ fz_transform_point(&t, m);
+ fz_transform_point(&u, m);
+ fz_transform_point(&v, m);
+ 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_rect *
+fz_expand_rect(fz_rect *a, float expand)
+{
+ if (fz_is_empty_rect(a)) return a;
+ if (fz_is_infinite_rect(a)) return a;
+ a->x0 -= expand;
+ a->y0 -= expand;
+ a->x1 += expand;
+ a->y1 += expand;
+ return a;
+}
+
+fz_rect *fz_include_point_in_rect(fz_rect *r, const fz_point *p)
+{
+ if (p->x < r->x0) r->x0 = p->x;
+ if (p->x > r->x1) r->x1 = p->x;
+ if (p->y < r->y0) r->y0 = p->y;
+ if (p->y > r->y1) r->y1 = p->y;
+
+ return r;
+}