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Public Member Functions | Static Public Member Functions
C_OUTLINE Class Reference

`#include <coutln.h>`

Inheritance diagram for C_OUTLINE:

List of all members.

## Public Member Functions

| C_OUTLINE ()
| C_OUTLINE (CRACKEDGE *startpt, ICOORD bot_left, ICOORD top_right, inT16 length)
| C_OUTLINE (ICOORD startpt, DIR128 *new_steps, inT16 length)
| C_OUTLINE (C_OUTLINE *srcline, FCOORD rotation)
| ~C_OUTLINE ()
BOOL8 | flag (C_OUTLINE_FLAGS mask) const
void | set_flag (C_OUTLINE_FLAGS mask, BOOL8 value)
C_OUTLINE_LIST * | child ()
const TBOX & | bounding_box () const
void | set_step (inT16 stepindex, inT8 stepdir)
void | set_step (inT16 stepindex, DIR128 stepdir)
const ICOORD & | start_pos () const
inT32 | pathlength () const
DIR128 | step_dir (inT16 index) const
ICOORD | step (inT16 index) const
inT32 | area ()
inT32 | perimeter ()
inT32 | outer_area ()
inT32 | count_transitions (inT32 threshold)
BOOL8 | operator< (const C_OUTLINE &other) const
BOOL8 | operator> (C_OUTLINE &other) const
inT16 | winding_number (ICOORD testpt) const
inT16 | turn_direction () const
void | reverse ()
void | move (const ICOORD vec)
void | RemoveSmallRecursive (int min_size, C_OUTLINE_IT *it)
void | render (int left, int top, Pix *pix) const
void | render_outline (int left, int top, Pix *pix) const
void | plot (ScrollView *window, ScrollView::Color colour) const
C_OUTLINE & | operator= (const C_OUTLINE &source)
Public Member Functions inherited from ELIST_LINK
| ELIST_LINK ()
| ELIST_LINK (const ELIST_LINK &)
void | operator= (const ELIST_LINK &)

## Static Public Member Functions

static void | FakeOutline (const TBOX &box, C_OUTLINE_LIST *outlines)
static C_OUTLINE * | deep_copy (const C_OUTLINE *src)
static ICOORD | chain_step (int chaindir)

## Detailed Description

Definition at line 44 of file coutln.h.

## Constructor & Destructor Documentation

C_OUTLINE::C_OUTLINE | ( |  | ) |

inline

Definition at line 47 of file coutln.h.

{ //empty constructor
steps = NULL;
}

C_OUTLINE::C_OUTLINE | ( | CRACKEDGE * | startpt,
|  | ICOORD | bot_left,
|  | ICOORD | top_right,
|  | inT16 | length
| ) |  |

Definition at line 44 of file coutln.cpp.

:box (bot_left, top_right), start (startpt->pos) {
inT16 stepindex; //index to step
CRACKEDGE *edgept; //current point
stepcount = length; //no of steps
if (length == 0) {
steps = NULL;
return;
}
//get memory
steps = (uinT8 *) alloc_mem (step_mem());
memset(steps, 0, step_mem());
edgept = startpt;
for (stepindex = 0; stepindex < length; stepindex++) {
//set compact step
set_step (stepindex, edgept->stepdir);
edgept = edgept->next;
}
}

C_OUTLINE::C_OUTLINE | ( | ICOORD | startpt,
|  | DIR128 * | new_steps,
|  | inT16 | length
| ) |  |

Definition at line 76 of file coutln.cpp.

:start (startpt) {
inT8 dirdiff; //direction difference
DIR128 prevdir; //previous direction
DIR128 dir; //current direction
DIR128 lastdir; //dir of last step
TBOX new_box; //easy bounding
inT16 stepindex; //index to step
inT16 srcindex; //source steps
ICOORD pos; //current position
pos = startpt;
stepcount = length; //no of steps
//get memory
steps = (uinT8 *) alloc_mem (step_mem());
memset(steps, 0, step_mem());
lastdir = new_steps[length - 1];
prevdir = lastdir;
for (stepindex = 0, srcindex = 0; srcindex < length;
stepindex++, srcindex++) {
new_box = TBOX (pos, pos);
box += new_box;
//copy steps
dir = new_steps[srcindex];
set_step(stepindex, dir);
dirdiff = dir - prevdir;
pos += step (stepindex);
if ((dirdiff == 64 || dirdiff == -64) && stepindex > 0) {
stepindex -= 2; //cancel there-and-back
prevdir = stepindex >= 0 ? step_dir (stepindex) : lastdir;
}
else
prevdir = dir;
}
ASSERT_HOST (pos.x () == startpt.x () && pos.y () == startpt.y ());
do {
dirdiff = step_dir (stepindex - 1) - step_dir (0);
if (dirdiff == 64 || dirdiff == -64) {
start += step (0);
stepindex -= 2; //cancel there-and-back
for (int i = 0; i < stepindex; ++i)
set_step(i, step_dir(i + 1));
}
}
while (stepindex > 1 && (dirdiff == 64 || dirdiff == -64));
stepcount = stepindex;
ASSERT_HOST (stepcount >= 4);
}

C_OUTLINE::C_OUTLINE | ( | C_OUTLINE * | srcline,
|  | FCOORD | rotation
| ) |  |

Definition at line 136 of file coutln.cpp.

{
TBOX new_box; //easy bounding
inT16 stepindex; //index to step
inT16 dirdiff; //direction change
ICOORD pos; //current position
ICOORD prevpos; //previous dest point
ICOORD destpos; //destination point
inT16 destindex; //index to step
DIR128 dir; //coded direction
uinT8 new_step;
stepcount = srcline->stepcount * 2;
if (stepcount == 0) {
steps = NULL;
box = srcline->box;
box.rotate(rotation);
return;
}
//get memory
steps = (uinT8 *) alloc_mem (step_mem());
memset(steps, 0, step_mem());
for (int iteration = 0; iteration < 2; ++iteration) {
DIR128 round1 = iteration == 0 ? 32 : 0;
DIR128 round2 = iteration != 0 ? 32 : 0;
pos = srcline->start;
prevpos = pos;
prevpos.rotate (rotation);
start = prevpos;
box = TBOX (start, start);
destindex = 0;
for (stepindex = 0; stepindex < srcline->stepcount; stepindex++) {
pos += srcline->step (stepindex);
destpos = pos;
destpos.rotate (rotation);
// printf("%i %i %i %i ", destpos.x(), destpos.y(), pos.x(), pos.y());
while (destpos.x () != prevpos.x () || destpos.y () != prevpos.y ()) {
dir = DIR128 (FCOORD (destpos - prevpos));
dir += 64; //turn to step style
new_step = dir.get_dir ();
// printf(" %i\n", new_step);
if (new_step & 31) {
set_step(destindex++, dir + round1);
prevpos += step(destindex - 1);
if (destindex < 2
|| ((dirdiff =
step_dir (destindex - 1) - step_dir (destindex - 2)) !=
-64 && dirdiff != 64)) {
set_step(destindex++, dir + round2);
prevpos += step(destindex - 1);
} else {
prevpos -= step(destindex - 1);
destindex--;
prevpos -= step(destindex - 1);
set_step(destindex - 1, dir + round2);
prevpos += step(destindex - 1);
}
}
else {
set_step(destindex++, dir);
prevpos += step(destindex - 1);
}
while (destindex >= 2 &&
((dirdiff =
step_dir (destindex - 1) - step_dir (destindex - 2)) == -64 ||
dirdiff == 64)) {
prevpos -= step(destindex - 1);
prevpos -= step(destindex - 2);
destindex -= 2; // Forget u turn
}
//ASSERT_HOST(prevpos.x() == destpos.x() && prevpos.y() == destpos.y());
new_box = TBOX (destpos, destpos);
box += new_box;
}
}
ASSERT_HOST (destpos.x () == start.x () && destpos.y () == start.y ());
dirdiff = step_dir (destindex - 1) - step_dir (0);
while ((dirdiff == 64 || dirdiff == -64) && destindex > 1) {
start += step (0);
destindex -= 2;
for (int i = 0; i < destindex; ++i)
set_step(i, step_dir(i + 1));
dirdiff = step_dir (destindex - 1) - step_dir (0);
}
if (destindex >= 4)
break;
}
ASSERT_HOST(destindex <= stepcount);
stepcount = destindex;
destpos = start;
for (stepindex = 0; stepindex < stepcount; stepindex++) {
destpos += step (stepindex);
}
ASSERT_HOST (destpos.x () == start.x () && destpos.y () == start.y ());
}

C_OUTLINE::~C_OUTLINE | ( |  | ) |

inline

Definition at line 64 of file coutln.h.

{ //destructor
if (steps != NULL)
free_mem(steps);
steps = NULL;
}

## Member Function Documentation

inT32 C_OUTLINE::area | ( |  | ) |

Definition at line 253 of file coutln.cpp.

{ //winding number
int stepindex; //current step
inT32 total_steps; //steps to do
inT32 total; //total area
ICOORD pos; //position of point
ICOORD next_step; //step to next pix
C_OUTLINE_IT it = child ();
pos = start_pos ();
total_steps = pathlength ();
total = 0;
for (stepindex = 0; stepindex < total_steps; stepindex++) {
//all intersected
next_step = step (stepindex);
if (next_step.x () < 0)
total += pos.y ();
else if (next_step.x () > 0)
total -= pos.y ();
pos += next_step;
}
for (it.mark_cycle_pt (); !it.cycled_list (); it.forward ())
total += it.data ()->area ();//add areas of children
return total;
}

const TBOX& C_OUTLINE::bounding_box | ( |  | ) | const

inline

Definition at line 85 of file coutln.h.

{
return box;
}

ICOORD C_OUTLINE::chain_step | ( | int | chaindir | ) |

static

Definition at line 723 of file coutln.cpp.

{
return step_coords[chaindir % 4];
}

C_OUTLINE_LIST* C_OUTLINE::child | ( |  | ) |

inline

Definition at line 80 of file coutln.h.

{ //get child list
return &children;
}

inT32 C_OUTLINE::count_transitions | ( | inT32 | threshold | ) |

Definition at line 335 of file coutln.cpp.

{
BOOL8 first_was_max_x; //what was first
BOOL8 first_was_max_y;
BOOL8 looking_for_max_x; //what is next
BOOL8 looking_for_min_x;
BOOL8 looking_for_max_y; //what is next
BOOL8 looking_for_min_y;
int stepindex; //current step
inT32 total_steps; //steps to do
//current limits
inT32 max_x, min_x, max_y, min_y;
inT32 initial_x, initial_y; //initial limits
inT32 total; //total changes
ICOORD pos; //position of point
ICOORD next_step; //step to next pix
pos = start_pos ();
total_steps = pathlength ();
total = 0;
max_x = min_x = pos.x ();
max_y = min_y = pos.y ();
looking_for_max_x = TRUE;
looking_for_min_x = TRUE;
looking_for_max_y = TRUE;
looking_for_min_y = TRUE;
first_was_max_x = FALSE;
first_was_max_y = FALSE;
initial_x = pos.x ();
initial_y = pos.y (); //stop uninit warning
for (stepindex = 0; stepindex < total_steps; stepindex++) {
//all intersected
next_step = step (stepindex);
pos += next_step;
if (next_step.x () < 0) {
if (looking_for_max_x && pos.x () < min_x)
min_x = pos.x ();
if (looking_for_min_x && max_x - pos.x () > threshold) {
if (looking_for_max_x) {
initial_x = max_x;
first_was_max_x = FALSE;
}
total++;
looking_for_max_x = TRUE;
looking_for_min_x = FALSE;
min_x = pos.x (); //reset min
}
}
else if (next_step.x () > 0) {
if (looking_for_min_x && pos.x () > max_x)
max_x = pos.x ();
if (looking_for_max_x && pos.x () - min_x > threshold) {
if (looking_for_min_x) {
initial_x = min_x; //remember first min
first_was_max_x = TRUE;
}
total++;
looking_for_max_x = FALSE;
looking_for_min_x = TRUE;
max_x = pos.x ();
}
}
else if (next_step.y () < 0) {
if (looking_for_max_y && pos.y () < min_y)
min_y = pos.y ();
if (looking_for_min_y && max_y - pos.y () > threshold) {
if (looking_for_max_y) {
initial_y = max_y; //remember first max
first_was_max_y = FALSE;
}
total++;
looking_for_max_y = TRUE;
looking_for_min_y = FALSE;
min_y = pos.y (); //reset min
}
}
else {
if (looking_for_min_y && pos.y () > max_y)
max_y = pos.y ();
if (looking_for_max_y && pos.y () - min_y > threshold) {
if (looking_for_min_y) {
initial_y = min_y; //remember first min
first_was_max_y = TRUE;
}
total++;
looking_for_max_y = FALSE;
looking_for_min_y = TRUE;
max_y = pos.y ();
}
}
}
if (first_was_max_x && looking_for_min_x) {
if (max_x - initial_x > threshold)
total++;
else
total--;
}
else if (!first_was_max_x && looking_for_max_x) {
if (initial_x - min_x > threshold)
total++;
else
total--;
}
if (first_was_max_y && looking_for_min_y) {
if (max_y - initial_y > threshold)
total++;
else
total--;
}
else if (!first_was_max_y && looking_for_max_y) {
if (initial_y - min_y > threshold)
total++;
else
total--;
}
return total;
}

static C_OUTLINE* C_OUTLINE::deep_copy | ( | const C_OUTLINE * | src | ) |

inline static

Definition at line 169 of file coutln.h.

{
C_OUTLINE* outline = new C_OUTLINE;
*outline = *src;
return outline;
}

void C_OUTLINE::FakeOutline | ( | const TBOX & | box,
|  | C_OUTLINE_LIST * | outlines
| ) |  |

static

Definition at line 237 of file coutln.cpp.

{
C_OUTLINE_IT ol_it(outlines);
// Make a C_OUTLINE from the bounds. This is a bit of a hack,
// as there is no outline, just a bounding box, but it works nicely.
CRACKEDGE start;
start.pos = box.topleft();
C_OUTLINE* outline = new C_OUTLINE(&start, box.topleft(), box.botright(), 0);
ol_it.add_to_end(outline);
}

BOOL8 C_OUTLINE::flag | ( | C_OUTLINE_FLAGS | mask | ) | const

inline

Definition at line 70 of file coutln.h.

{ //flag to test
return flags.bit (mask);
}

void C_OUTLINE::move | ( | const ICOORD | vec | ) |

Definition at line 592 of file coutln.cpp.

{
C_OUTLINE_IT it(&children); // iterator
box.move (vec);
start += vec;
for (it.mark_cycle_pt (); !it.cycled_list (); it.forward ())
it.data ()->move (vec); // move child outlines
}

BOOL8 C_OUTLINE::operator< | ( | const C_OUTLINE & | other | ) | const

Definition at line 464 of file coutln.cpp.

{
inT16 count = 0; //winding count
ICOORD pos; //position of point
inT32 stepindex; //index to cstep
if (!box.overlap (other.box))
return FALSE; //can't be contained
if (stepcount == 0)
return other.box.contains(this->box);
pos = start;
for (stepindex = 0; stepindex < stepcount
&& (count = other.winding_number (pos)) == INTERSECTING; stepindex++)
pos += step (stepindex); //try all points
if (count == INTERSECTING) {
//all intersected
pos = other.start;
for (stepindex = 0; stepindex < other.stepcount
&& (count = winding_number (pos)) == INTERSECTING; stepindex++)
//try other way round
pos += other.step (stepindex);
return count == INTERSECTING || count == 0;
}
return count != 0;
}

C_OUTLINE & C_OUTLINE::operator= | ( | const C_OUTLINE & | source | ) |

Definition at line 707 of file coutln.cpp.

{
box = source.box;
start = source.start;
if (steps != NULL)
free_mem(steps);
stepcount = source.stepcount;
steps = (uinT8 *) alloc_mem (step_mem());
memmove (steps, source.steps, step_mem());
if (!children.empty ())
children.clear ();
children.deep_copy(&source.children, &deep_copy);
return *this;
}

BOOL8 C_OUTLINE::operator> | ( | C_OUTLINE & | other | ) | const

inline

Definition at line 132 of file coutln.h.

{
return other < *this; //use the < to do it
}

inT32 C_OUTLINE::outer_area | ( |  | ) |

Definition at line 303 of file coutln.cpp.

{ //winding number
int stepindex; //current step
inT32 total_steps; //steps to do
inT32 total; //total area
ICOORD pos; //position of point
ICOORD next_step; //step to next pix
pos = start_pos ();
total_steps = pathlength ();
if (total_steps == 0)
return box.area();
total = 0;
for (stepindex = 0; stepindex < total_steps; stepindex++) {
//all intersected
next_step = step (stepindex);
if (next_step.x () < 0)
total += pos.y ();
else if (next_step.x () > 0)
total -= pos.y ();
pos += next_step;
}
return total;
}

inT32 C_OUTLINE::pathlength | ( |  | ) | const

inline

Definition at line 111 of file coutln.h.

{ //get path length
return stepcount;
}

inT32 C_OUTLINE::perimeter | ( |  | ) |

Definition at line 285 of file coutln.cpp.

{
inT32 total_steps; // Return value.
C_OUTLINE_IT it = child();
total_steps = pathlength();
for (it.mark_cycle_pt(); !it.cycled_list(); it.forward())
total_steps += it.data()->pathlength(); // Add perimeters of children.
return total_steps;
}

void C_OUTLINE::plot | ( | ScrollView * | window,
|  | ScrollView::Color | colour
| ) |  | const

Definition at line 667 of file coutln.cpp.

{
inT16 stepindex; // index to cstep
ICOORD pos; // current position
DIR128 stepdir; // direction of step
pos = start; // current position
window->Pen(colour);
if (stepcount == 0) {
window->Rectangle(box.left(), box.top(), box.right(), box.bottom());
return;
}
window->SetCursor(pos.x(), pos.y());
stepindex = 0;
while (stepindex < stepcount) {
pos += step(stepindex); // step to next
stepdir = step_dir(stepindex);
stepindex++; // count steps
// merge straight lines
while (stepindex < stepcount &&
stepdir.get_dir() == step_dir(stepindex).get_dir()) {
pos += step(stepindex);
stepindex++;
}
window->DrawTo(pos.x(), pos.y());
}
}

void C_OUTLINE::RemoveSmallRecursive | ( | int | min_size,
|  | C_OUTLINE_IT * | it
| ) |  |

Definition at line 609 of file coutln.cpp.

{
if (box.width() < min_size || box.height() < min_size) {
ASSERT_HOST(this == it->data());
delete it->extract(); // Too small so get rid of it and any children.
} else if (!children.empty()) {
// Search the children of this, deleting any that are too small.
C_OUTLINE_IT child_it(&children);
for (child_it.mark_cycle_pt(); !child_it.cycled_list();
child_it.forward()) {
C_OUTLINE* child = child_it.data();
child->RemoveSmallRecursive(min_size, &child_it);
}
}
}

void C_OUTLINE::render | ( | int | left,
|  | int | top,
|  | Pix * | pix
| ) |  | const

Definition at line 626 of file coutln.cpp.

{
ICOORD pos = start;
for (int stepindex = 0; stepindex < stepcount; ++stepindex) {
ICOORD next_step = step(stepindex);
if (next_step.y() < 0) {
pixRasterop(pix, 0, top - pos.y(), pos.x() - left, 1,
PIX_NOT(PIX_DST), NULL, 0, 0);
} else if (next_step.y() > 0) {
pixRasterop(pix, 0, top - pos.y() - 1, pos.x() - left, 1,
PIX_NOT(PIX_DST), NULL, 0, 0);
}
pos += next_step;
}
}

void C_OUTLINE::render_outline | ( | int | left,
|  | int | top,
|  | Pix * | pix
| ) |  | const

Definition at line 643 of file coutln.cpp.

{
ICOORD pos = start;
for (int stepindex = 0; stepindex < stepcount; ++stepindex) {
ICOORD next_step = step(stepindex);
if (next_step.y() < 0) {
pixSetPixel(pix, pos.x() - left, top - pos.y(), 1);
} else if (next_step.y() > 0) {
pixSetPixel(pix, pos.x() - left - 1, top - pos.y() - 1, 1);
} else if (next_step.x() < 0) {
pixSetPixel(pix, pos.x() - left - 1, top - pos.y(), 1);
} else if (next_step.x() > 0) {
pixSetPixel(pix, pos.x() - left, top - pos.y() - 1, 1);
}
pos += next_step;
}
}

void C_OUTLINE::reverse | ( |  | ) |

Definition at line 569 of file coutln.cpp.

{ //reverse drection
DIR128 halfturn = MODULUS / 2; //amount to shift
DIR128 stepdir; //direction of step
inT16 stepindex; //index to cstep
inT16 farindex; //index to other side
inT16 halfsteps; //half of stepcount
halfsteps = (stepcount + 1) / 2;
for (stepindex = 0; stepindex < halfsteps; stepindex++) {
farindex = stepcount - stepindex - 1;
stepdir = step_dir (stepindex);
set_step (stepindex, step_dir (farindex) + halfturn);
set_step (farindex, stepdir + halfturn);
}
}

void C_OUTLINE::set_flag | ( | C_OUTLINE_FLAGS | mask,
|  | BOOL8 | value
| ) |  |

inline

Definition at line 74 of file coutln.h.

{ //value to set
flags.set_bit (mask, value);
}

void C_OUTLINE::set_step | ( | inT16 | stepindex,
|  | inT8 | stepdir
| ) |  |

inline

Definition at line 88 of file coutln.h.

{ //chain code
int shift = stepindex%4 * 2;
uinT8 mask = 3 << shift;
steps[stepindex/4] = ((stepdir << shift) & mask) |
(steps[stepindex/4] & ~mask);
//squeeze 4 into byte
}

void C_OUTLINE::set_step | ( | inT16 | stepindex,
|  | DIR128 | stepdir
| ) |  |

inline

Definition at line 97 of file coutln.h.

{ //direction
//clean it
inT8 chaindir = stepdir.get_dir() >> (DIRBITS - 2);
//difference
set_step(stepindex, chaindir);
//squeeze 4 into byte
}

const ICOORD& C_OUTLINE::start_pos | ( |  | ) | const

inline

Definition at line 108 of file coutln.h.

{
return start;
}

ICOORD C_OUTLINE::step | ( | inT16 | index | ) | const

inline

Definition at line 120 of file coutln.h.

{ //index of step
return step_coords[(steps[index/4] >> (index%4 * 2)) & STEP_MASK];
}

DIR128 C_OUTLINE::step_dir | ( | inT16 | index | ) | const

inline

Definition at line 115 of file coutln.h.

{
return DIR128((inT16)(((steps[index/4] >> (index%4 * 2)) & STEP_MASK) <<
(DIRBITS - 2)));
}

inT16 C_OUTLINE::turn_direction | ( |  | ) | const

Definition at line 540 of file coutln.cpp.

{ //winding number
DIR128 prevdir; //previous direction
DIR128 dir; //current direction
inT16 stepindex; //index to cstep
inT8 dirdiff; //direction difference
inT16 count; //winding count
if (stepcount == 0)
return 128;
count = 0;
prevdir = step_dir (stepcount - 1);
for (stepindex = 0; stepindex < stepcount; stepindex++) {
dir = step_dir (stepindex);
dirdiff = dir - prevdir;
ASSERT_HOST (dirdiff == 0 || dirdiff == 32 || dirdiff == -32);
count += dirdiff;
prevdir = dir;
}
ASSERT_HOST (count == 128 || count == -128);
return count; //winding number
}

inT16 C_OUTLINE::winding_number | ( | ICOORD | testpt | ) | const

Definition at line 500 of file coutln.cpp.

{
inT16 stepindex; //index to cstep
inT16 count; //winding count
ICOORD vec; //to current point
ICOORD stepvec; //step vector
inT32 cross; //cross product
vec = start - point; //vector to it
count = 0;
for (stepindex = 0; stepindex < stepcount; stepindex++) {
stepvec = step (stepindex); //get the step
//crossing the line
if (vec.y () <= 0 && vec.y () + stepvec.y () > 0) {
cross = vec * stepvec; //cross product
if (cross > 0)
count++; //crossing right half
else if (cross == 0)
return INTERSECTING; //going through point
}
else if (vec.y () > 0 && vec.y () + stepvec.y () <= 0) {
cross = vec * stepvec;
if (cross < 0)
count--; //crossing back
else if (cross == 0)
return INTERSECTING; //illegal
}
vec += stepvec; //sum vectors
}
return count; //winding number
}

The documentation for this class was generated from the following files:

- /mnt/data/src/tesseract-ocr/ccstruct/coutln.h
- /mnt/data/src/tesseract-ocr/ccstruct/coutln.cpp