matplotlib/src/path_converters.h at matplotlib_ppc64le_fix · ManthanIBM/matplotlib · GitHub

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/* -*- mode: c++; c-basic-offset: 4 -*- */

#ifndef MPL_PATH_CONVERTERS_H

#define MPL_PATH_CONVERTERS_H

#include <pybind11/pybind11.h>

#include <cmath>

#include <cstdint>

#include <limits>

#include "agg_clip_liang_barsky.h"

#include "mplutils.h"

#include "agg_conv_segmentator.h"

This file contains a number of vertex converters that modify

paths. They all work as iterators, where the output is generated

on-the-fly, and don't require a copy of the full data.

Each class represents a discrete step in a "path-cleansing" pipeline.

They are currently applied in the following order in the Agg backend:

1. Affine transformation (implemented in Agg, not here)

2. PathNanRemover: skips over segments containing non-finite numbers

by inserting MOVETO commands

3. PathClipper: Clips line segments to a given rectangle. This is

helpful for data reduction, and also to avoid a limitation in

Agg where coordinates cannot be larger than 24-bit signed

integers.

4. PathSnapper: Rounds the path to the nearest center-pixels.

This makes rectilinear curves look much better.

5. PathSimplifier: Removes line segments from highly dense paths

that would not have an impact on their appearance. Speeds up

rendering and reduces file sizes.

6. curve-to-line-segment conversion (implemented in Agg, not here)

7. stroking (implemented in Agg, not here)

/************************************************************

This is a base class for vertex converters that need to queue their

output. It is designed to be as fast as possible vs. the STL's queue

which is more flexible.

template <int QueueSize>

class EmbeddedQueue

{

protected:

EmbeddedQueue() : m_queue_read(0), m_queue_write(0)

{

// empty

}

struct item

{

item() = default;

inline void set(const unsigned cmd_, const double x_, const double y_)

{

cmd = cmd_;

x = x_;

y = y_;

}

unsigned cmd;

double x;

double y;

};

int m_queue_read;

int m_queue_write;

item m_queue[QueueSize];

inline void queue_push(const unsigned cmd, const double x, const double y)

{

m_queue[m_queue_write++].set(cmd, x, y);

}

inline bool queue_nonempty()

{

return m_queue_read < m_queue_write;

}

inline bool queue_pop(unsigned *cmd, double *x, double *y)

{

if (queue_nonempty()) {

const item &front = m_queue[m_queue_read++];

*cmd = front.cmd;

*x = front.x;

*y = front.y;

return true;

}

m_queue_read = 0;

m_queue_write = 0;

return false;

}

inline void queue_clear()

{

m_queue_read = 0;

m_queue_write = 0;

}

};

/* Defines when path segment types have more than one vertex */

static const size_t num_extra_points_map[] =

{0, 0, 0, 1,

2, 0, 0, 0,

0, 0, 0, 0,

0, 0, 0, 0

};

/* An implementation of a simple linear congruential random number

generator. This is a "classic" and fast RNG which works fine for

our purposes of sketching lines, but should not be used for things

that matter, like crypto. We are implementing this ourselves

rather than using the C stdlib so that the seed state is not shared

with other third-party code. There are recent C++ options, but we

still require nothing later than C++98 for compatibility

reasons. */

class RandomNumberGenerator

{

private:

/* These are the same constants from MS Visual C++, which

has the nice property that the modulus is 2^32, thus

saving an explicit modulo operation

static const uint32_t a = 214013;

static const uint32_t c = 2531011;

uint32_t m_seed;

public:

RandomNumberGenerator() : m_seed(0) {}

RandomNumberGenerator(int seed) : m_seed(seed) {}

void seed(int seed)

{

m_seed = seed;

}

double get_double()

{

m_seed = (a * m_seed + c);

return (double)m_seed / (double)(1LL << 32);

}

};

PathNanRemover is a vertex converter that removes non-finite values

from the vertices list, and inserts MOVETO commands as necessary to

skip over them. If a curve segment contains at least one non-finite

value, the entire curve segment will be skipped.

template <class VertexSource>

class PathNanRemover : protected EmbeddedQueue<4>

{

VertexSource *m_source;

bool m_remove_nans;

bool m_has_codes;

bool valid_segment_exists;

bool m_last_segment_valid;

bool m_was_broken;

double m_initX;

double m_initY;

public:

/* has_codes should be true if the path contains bezier curve segments, or

* closed loops, as this requires a slower algorithm to remove the NaNs.

* When in doubt, set to true.

PathNanRemover(VertexSource &source, bool remove_nans, bool has_codes)

: m_source(&source), m_remove_nans(remove_nans), m_has_codes(has_codes),

m_last_segment_valid(false), m_was_broken(false),

m_initX(nan("")), m_initY(nan(""))

{

// ignore all close/end_poly commands until after the first valid

// (nan-free) command is encountered

valid_segment_exists = false;

}

inline void rewind(unsigned path_id)

{

queue_clear();

m_source->rewind(path_id);

}

inline unsigned vertex(double *x, double *y)

{

unsigned code;

if (!m_remove_nans) {

return m_source->vertex(x, y);

}

if (m_has_codes) {

/* This is the slow method for when there might be curves or closed

* loops. */

if (queue_pop(&code, x, y)) {

return code;

}

bool needs_move_to = false;

while (true) {

/* The approach here is to push each full curve

segment into the queue. If any non-finite values

are found along the way, the queue is emptied, and

the next curve segment is handled. */

code = m_source->vertex(x, y);

/* The vertices attached to STOP and CLOSEPOLY are never used,

* so we leave them as-is even if NaN. */

if (code == agg::path_cmd_stop) {

return code;

} else if (code == (agg::path_cmd_end_poly |

agg::path_flags_close) &&

valid_segment_exists) {

/* However, CLOSEPOLY only makes sense if a valid MOVETO

* command has already been emitted. But if a NaN was

* removed in the path, then we cannot close it as it is no

* longer a loop. We must emulate that by inserting a

* LINETO instead. */

if (m_was_broken) {

if (m_last_segment_valid && (

std::isfinite(m_initX) &&

std::isfinite(m_initY))) {

/* Join to start if both ends are valid. */

queue_push(agg::path_cmd_line_to, m_initX, m_initY);

break;

} else {

/* Skip the close, in case there are additional

* subpaths. */

continue;

}

m_was_broken = false;

break;

} else {

return code;

}

} else if (code == agg::path_cmd_move_to) {

/* Save the initial point in order to produce the last

* segment closing a loop, *if* we broke the loop. */

m_initX = *x;

m_initY = *y;

m_was_broken = false;

}

if (needs_move_to) {

queue_push(agg::path_cmd_move_to, *x, *y);

}

size_t num_extra_points = num_extra_points_map[code & 0xF];

m_last_segment_valid = (std::isfinite(*x) && std::isfinite(*y));

queue_push(code, *x, *y);

/* Note: this test cannot be short-circuited, since we need to

advance through the entire curve no matter what */

for (size_t i = 0; i < num_extra_points; ++i) {

m_source->vertex(x, y);

m_last_segment_valid = m_last_segment_valid &&

(std::isfinite(*x) && std::isfinite(*y));

queue_push(code, *x, *y);

}

if (m_last_segment_valid) {

valid_segment_exists = true;

break;

}

m_was_broken = true;

queue_clear();

/* If the last point is finite, we use that for the

moveto, otherwise, we'll use the first vertex of

the next curve. */

if (std::isfinite(*x) && std::isfinite(*y)) {

queue_push(agg::path_cmd_move_to, *x, *y);

needs_move_to = false;

} else {

needs_move_to = true;

}

if (queue_pop(&code, x, y)) {

return code;

} else {

return agg::path_cmd_stop;

}

} else // !m_has_codes

{

/* This is the fast path for when we know we have no codes. */

code = m_source->vertex(x, y);

if (code == agg::path_cmd_stop ||

(code == (agg::path_cmd_end_poly | agg::path_flags_close) &&

valid_segment_exists)) {

return code;

}

if (!(std::isfinite(*x) && std::isfinite(*y))) {

do {

code = m_source->vertex(x, y);

if (code == agg::path_cmd_stop ||

(code == (agg::path_cmd_end_poly | agg::path_flags_close) &&

valid_segment_exists)) {

return code;

}

} while (!(std::isfinite(*x) && std::isfinite(*y)));

return agg::path_cmd_move_to;

}

valid_segment_exists = true;

return code;

}

};

/************************************************************

PathClipper uses the Liang-Barsky line clipping algorithm (as

implemented in Agg) to clip the path to a given rectangle. Lines

will never extend outside of the rectangle. Curve segments are not

clipped, but are always included in their entirety.

template <class VertexSource>

class PathClipper : public EmbeddedQueue<3>

{

VertexSource *m_source;

bool m_do_clipping;

agg::rect_base<double> m_cliprect;

double m_lastX;

double m_lastY;

bool m_moveto;

double m_initX;

double m_initY;

bool m_has_init;

bool m_was_clipped;

public:

PathClipper(VertexSource &source, bool do_clipping, double width, double height)

: m_source(&source),

m_do_clipping(do_clipping),

m_cliprect(-1.0, -1.0, width + 1.0, height + 1.0),

m_lastX(nan("")),

m_lastY(nan("")),

m_moveto(true),

m_initX(nan("")),

m_initY(nan("")),

m_has_init(false),

m_was_clipped(false)

{

// empty

}

PathClipper(VertexSource &source, bool do_clipping, const agg::rect_base<double> &rect)

: m_source(&source),

m_do_clipping(do_clipping),

m_cliprect(rect),

m_lastX(nan("")),

m_lastY(nan("")),

m_moveto(true),

m_initX(nan("")),

m_initY(nan("")),

m_has_init(false),

m_was_clipped(false)

{

m_cliprect.x1 -= 1.0;

m_cliprect.y1 -= 1.0;

m_cliprect.x2 += 1.0;

m_cliprect.y2 += 1.0;

}

inline void rewind(unsigned path_id)

{

m_has_init = false;

m_was_clipped = false;

m_moveto = true;

m_source->rewind(path_id);

}

int draw_clipped_line(double x0, double y0, double x1, double y1,

bool closed=false)

{

unsigned moved = agg::clip_line_segment(&x0, &y0, &x1, &y1, m_cliprect);

// moved >= 4 - Fully clipped

// moved & 1 != 0 - First point has been moved

// moved & 2 != 0 - Second point has been moved

m_was_clipped = m_was_clipped || (moved != 0);

if (moved < 4) {

if (moved & 1 || m_moveto) {

queue_push(agg::path_cmd_move_to, x0, y0);

}

queue_push(agg::path_cmd_line_to, x1, y1);

if (closed && !m_was_clipped) {

// Close the path only if the end point hasn't moved.

queue_push(agg::path_cmd_end_poly | agg::path_flags_close,

x1, y1);

}

m_moveto = false;

return 1;

}

return 0;

}

unsigned vertex(double *x, double *y)

{

unsigned code;

bool emit_moveto = false;

if (!m_do_clipping) {

// If not doing any clipping, just pass along the vertices verbatim

return m_source->vertex(x, y);

}

/* This is the slow path where we actually do clipping */

if (queue_pop(&code, x, y)) {

return code;

}

while ((code = m_source->vertex(x, y)) != agg::path_cmd_stop) {

emit_moveto = false;

switch (code) {

case (agg::path_cmd_end_poly | agg::path_flags_close):

if (m_has_init) {

// Queue the line from last point to the initial point, and

// if never clipped, add a close code.

draw_clipped_line(m_lastX, m_lastY, m_initX, m_initY,

true);

} else {

// An empty path that is immediately closed.

queue_push(

agg::path_cmd_end_poly | agg::path_flags_close,

m_lastX, m_lastY);

}

// If paths were not clipped, then the above code queued

// something, and we should exit the loop. Otherwise, continue

// to the next point, as there may be a new subpath.

if (queue_nonempty()) {

goto exit_loop;

}

break;

case agg::path_cmd_move_to:

// was the last command a moveto (and we have

// seen at least one command ?

// if so, shove it in the queue if in clip box

if (m_moveto && m_has_init &&

m_lastX >= m_cliprect.x1 &&

m_lastX <= m_cliprect.x2 &&

m_lastY >= m_cliprect.y1 &&

m_lastY <= m_cliprect.y2) {

// push the last moveto onto the queue

queue_push(agg::path_cmd_move_to, m_lastX, m_lastY);

// flag that we need to emit it

emit_moveto = true;

}

// update the internal state for this moveto

m_initX = m_lastX = *x;

m_initY = m_lastY = *y;

m_has_init = true;

m_moveto = true;

m_was_clipped = false;

// if the last command was moveto exit the loop to emit the code

if (emit_moveto) {

goto exit_loop;

}

// else, break and get the next point

break;

case agg::path_cmd_line_to:

if (draw_clipped_line(m_lastX, m_lastY, *x, *y)) {

m_lastX = *x;

m_lastY = *y;

goto exit_loop;

}

m_lastX = *x;

m_lastY = *y;

break;

default:

if (m_moveto) {

queue_push(agg::path_cmd_move_to, m_lastX, m_lastY);

m_moveto = false;

}

queue_push(code, *x, *y);

m_lastX = *x;

m_lastY = *y;

goto exit_loop;

}

exit_loop:

if (queue_pop(&code, x, y)) {

return code;

}

if (m_moveto && m_has_init &&

m_lastX >= m_cliprect.x1 &&

m_lastX <= m_cliprect.x2 &&

m_lastY >= m_cliprect.y1 &&

m_lastY <= m_cliprect.y2) {

*x = m_lastX;

*y = m_lastY;

m_moveto = false;

return agg::path_cmd_move_to;

}

return agg::path_cmd_stop;

}

};

/************************************************************

PathSnapper rounds vertices to their nearest center-pixels. This

makes rectilinear paths (rectangles, horizontal and vertical lines

etc.) look much cleaner.

enum e_snap_mode {

SNAP_AUTO,

SNAP_FALSE,

SNAP_TRUE

};

namespace PYBIND11_NAMESPACE { namespace detail {

template <> struct type_caster<e_snap_mode> {

public:

PYBIND11_TYPE_CASTER(e_snap_mode, const_name("e_snap_mode"));

bool load(handle src, bool) {

if (src.is_none()) {

value = SNAP_AUTO;

return true;

}

value = src.cast<bool>() ? SNAP_TRUE : SNAP_FALSE;

return true;

}

};

}} // namespace PYBIND11_NAMESPACE::detail

template <class VertexSource>

class PathSnapper

{

private:

VertexSource *m_source;

bool m_snap;

double m_snap_value;

static bool should_snap(VertexSource &path, e_snap_mode snap_mode, unsigned total_vertices)

{

// If this contains only straight horizontal or vertical lines, it should be

// snapped to the nearest pixels

double x0 = 0, y0 = 0, x1 = 0, y1 = 0;

unsigned code;

switch (snap_mode) {

case SNAP_AUTO:

if (total_vertices > 1024) {

return false;

}

code = path.vertex(&x0, &y0);

if (code == agg::path_cmd_stop) {

return false;

}

while ((code = path.vertex(&x1, &y1)) != agg::path_cmd_stop) {

switch (code) {

case agg::path_cmd_curve3:

case agg::path_cmd_curve4:

return false;

case agg::path_cmd_line_to:

if (fabs(x0 - x1) >= 1e-4 && fabs(y0 - y1) >= 1e-4) {

return false;

}

x0 = x1;

y0 = y1;

}

return true;

case SNAP_FALSE:

return false;

case SNAP_TRUE:

return true;

}

return false;

}

public:

snap_mode should be one of:

- SNAP_AUTO: Examine the path to determine if it should be snapped

- SNAP_TRUE: Force snapping

- SNAP_FALSE: No snapping

PathSnapper(VertexSource &source,

e_snap_mode snap_mode,

unsigned total_vertices = 15,

double stroke_width = 0.0)

: m_source(&source)

{

m_snap = should_snap(source, snap_mode, total_vertices);

if (m_snap) {

int is_odd = mpl_round_to_int(stroke_width) % 2;

m_snap_value = (is_odd) ? 0.5 : 0.0;

}

source.rewind(0);

}

inline void rewind(unsigned path_id)

{

m_source->rewind(path_id);

}

inline unsigned vertex(double *x, double *y)

{

unsigned code;

code = m_source->vertex(x, y);

if (m_snap && agg::is_vertex(code)) {

*x = floor(*x + 0.5) + m_snap_value;

*y = floor(*y + 0.5) + m_snap_value;

}

return code;

}

inline bool is_snapping()

{

return m_snap;

}

};

/************************************************************

PathSimplifier reduces the number of vertices in a dense path without

changing its appearance.

template <class VertexSource>

class PathSimplifier : protected EmbeddedQueue<9>

{

public:

/* Set simplify to true to perform simplification */

PathSimplifier(VertexSource &source, bool do_simplify, double simplify_threshold)

: m_source(&source),

m_simplify(do_simplify),

/* we square simplify_threshold so that we can compute

norms without doing the square root every step. */

m_simplify_threshold(simplify_threshold * simplify_threshold),

m_moveto(true),

m_after_moveto(false),

m_clipped(false),

// whether the most recent MOVETO vertex is valid

m_has_init(false),

// the most recent MOVETO vertex

m_initX(0.0),

m_initY(0.0),

// the x, y values from last iteration

m_lastx(0.0),

m_lasty(0.0),

// the dx, dy comprising the original vector, used in conjunction

// with m_currVecStart* to define the original vector.

m_origdx(0.0),

m_origdy(0.0),

// the squared norm of the original vector

m_origdNorm2(0.0),

// maximum squared norm of vector in forward (parallel) direction

m_dnorm2ForwardMax(0.0),

// maximum squared norm of vector in backward (anti-parallel) direction

m_dnorm2BackwardMax(0.0),

// was the last point the furthest from lastWritten in the

// forward (parallel) direction?

m_lastForwardMax(false),

// was the last point the furthest from lastWritten in the

// backward (anti-parallel) direction?

m_lastBackwardMax(false),

// added to queue when _push is called

m_nextX(0.0),

m_nextY(0.0),

// added to queue when _push is called if any backwards

// (anti-parallel) vectors were observed

m_nextBackwardX(0.0),

m_nextBackwardY(0.0),

// start of the current vector that is being simplified

m_currVecStartX(0.0),

m_currVecStartY(0.0)

{

// empty

}

inline void rewind(unsigned path_id)

{

queue_clear();

m_moveto = true;

m_source->rewind(path_id);

}

unsigned vertex(double *x, double *y)

{

unsigned cmd;

/* The simplification algorithm doesn't support curves or compound paths

so we just don't do it at all in that case... */

if (!m_simplify) {

return m_source->vertex(x, y);

}

/* idea: we can skip drawing many lines: we can combine

sequential parallel lines into a

single line instead of redrawing lines over the same

points. The loop below works a bit like a state machine,

where what it does depends on what it did in the last

looping. To test whether sequential lines are close to

parallel, I calculate the distance moved perpendicular to

the last line. Once it gets too big, the lines cannot be

combined. */

/* This code was originally written by Allan Haldane and I

have modified to work in-place -- meaning not creating an

entirely new path list each time. In order to do that

without too much additional code complexity, it keeps a

small queue around so that multiple points can be emitted

in a single call, and those points will be popped from the

queue in subsequent calls. The following block will empty

the queue before proceeding to the main loop below.

-- Michael Droettboom */

/* This code was originally written by Allan Haldane and

updated by Michael Droettboom. I have modified it to

handle anti-parallel vectors. This is done essentially

the same way as parallel vectors, but requires a little

additional book-keeping to track whether or not we have

observed an anti-parallel vector during the current run.

-- Kevin Rose */

if (queue_pop(&cmd, x, y)) {

return cmd;

}

/* The main simplification loop. The point is to consume only

as many points as necessary until something has been added

to the outbound queue, not to run through the entire path

in one go. This eliminates the need to allocate and fill

an entire additional path array on each draw. */

while ((cmd = m_source->vertex(x, y)) != agg::path_cmd_stop) {

/* if we are starting a new path segment, move to the first point

+ init */

if (m_moveto || cmd == agg::path_cmd_move_to) {

/* m_moveto check is not generally needed because

m_source generates an initial moveto; but it is

retained for safety in case circumstances arise

where this is not true. */

if (m_origdNorm2 != 0.0 && !m_after_moveto) {

/* m_origdNorm2 is nonzero only if we have a

vector; the m_after_moveto check ensures we

push this vector to the queue only once. */

_push(x, y);

}

m_after_moveto = true;

if (std::isfinite(*x) && std::isfinite(*y)) {

m_has_init = true;

m_initX = *x;

m_initY = *y;

} else {

m_has_init = false;

}

m_lastx = *x;

m_lasty = *y;

m_moveto = false;

m_origdNorm2 = 0.0;

m_dnorm2BackwardMax = 0.0;

m_clipped = true;

if (queue_nonempty()) {

/* If we did a push, empty the queue now. */

break;

}

continue;

}

m_after_moveto = false;

if(agg::is_close(cmd)) {

if (m_has_init) {

/* If we have a valid initial vertex, then

replace the current vertex with the initial vertex */

*x = m_initX;

*y = m_initY;

} else {

/* If we don't have a valid initial vertex, then

we can't close the path, so we skip the vertex */

continue;

}

/* NOTE: We used to skip this very short segments, but if

you have a lot of them cumulatively, you can miss

maxima or minima in the data. */

/* Don't render line segments less than one pixel long */

/* if (fabs(*x - m_lastx) < 1.0 && fabs(*y - m_lasty) < 1.0) */

/* { */

/* continue; */

/* } */

/* if we have no orig vector, set it to this vector and

continue. this orig vector is the reference vector we

will build up the line to */

if (m_origdNorm2 == 0.0) {

if (m_clipped) {

queue_push(agg::path_cmd_move_to, m_lastx, m_lasty);

m_clipped = false;

}

m_origdx = *x - m_lastx;

m_origdy = *y - m_lasty;

m_origdNorm2 = m_origdx * m_origdx + m_origdy * m_origdy;

// set all the variables to reflect this new orig vector

m_dnorm2ForwardMax = m_origdNorm2;

m_dnorm2BackwardMax = 0.0;

m_lastForwardMax = true;

m_lastBackwardMax = false;

m_currVecStartX = m_lastx;

m_currVecStartY = m_lasty;

m_nextX = m_lastx = *x;

m_nextY = m_lasty = *y;

continue;

}

/* If got to here, then we have an orig vector and we just got

a vector in the sequence. */

/* Check that the perpendicular distance we have moved

from the last written point compared to the line we are

building is not too much. If o is the orig vector (we

are building on), and v is the vector from the last

written point to the current point, then the

perpendicular vector is p = v - (o.v)o/(o.o)

(here, a.b indicates the dot product of a and b). */

/* get the v vector */

double totdx = *x - m_currVecStartX;

double totdy = *y - m_currVecStartY;

/* get the dot product o.v */

double totdot = m_origdx * totdx + m_origdy * totdy;

/* get the para vector ( = (o.v)o/(o.o)) */

double paradx = totdot * m_origdx / m_origdNorm2;

double parady = totdot * m_origdy / m_origdNorm2;

/* get the perp vector ( = v - para) */

double perpdx = totdx - paradx;

double perpdy = totdy - parady;

/* get the squared norm of perp vector ( = p.p) */

double perpdNorm2 = perpdx * perpdx + perpdy * perpdy;

/* If the perpendicular vector is less than

m_simplify_threshold pixels in size, then merge

current x,y with the current vector */

if (perpdNorm2 < m_simplify_threshold) {

/* check if the current vector is parallel or

anti-parallel to the orig vector. In either case,

test if it is the longest of the vectors

we are merging in that direction. If it is, then

update the current vector in that direction. */

double paradNorm2 = paradx * paradx + parady * parady;

m_lastForwardMax = false;

m_lastBackwardMax = false;

if (totdot > 0.0) {

if (paradNorm2 > m_dnorm2ForwardMax) {

m_lastForwardMax = true;

m_dnorm2ForwardMax = paradNorm2;

m_nextX = *x;

m_nextY = *y;

}

} else {

if (paradNorm2 > m_dnorm2BackwardMax) {

m_lastBackwardMax = true;

m_dnorm2BackwardMax = paradNorm2;

m_nextBackwardX = *x;

m_nextBackwardY = *y;

}

m_lastx = *x;

m_lasty = *y;

continue;

}

/* If we get here, then this vector was not similar enough to the

line we are building, so we need to draw that line and start the

next one. */

/* If the line needs to extend in the opposite direction from the

direction we are drawing in, move back to we start drawing from

back there. */

_push(x, y);

break;

}

/* Fill the queue with the remaining vertices if we've finished the

path in the above loop. */

if (cmd == agg::path_cmd_stop) {

if (m_origdNorm2 != 0.0) {

queue_push((m_moveto || m_after_moveto) ? agg::path_cmd_move_to

: agg::path_cmd_line_to,

m_nextX,

m_nextY);

if (m_dnorm2BackwardMax > 0.0) {

queue_push((m_moveto || m_after_moveto) ? agg::path_cmd_move_to

: agg::path_cmd_line_to,

m_nextBackwardX,

m_nextBackwardY);

}

m_moveto = false;

}

queue_push((m_moveto || m_after_moveto) ? agg::path_cmd_move_to : agg::path_cmd_line_to,

m_lastx,

m_lasty);

m_moveto = false;

queue_push(agg::path_cmd_stop, 0.0, 0.0);

}

/* Return the first item in the queue, if any, otherwise

indicate that we're done. */

if (queue_pop(&cmd, x, y)) {

return cmd;

} else {

return agg::path_cmd_stop;

}

private:

VertexSource *m_source;

bool m_simplify;

double m_simplify_threshold;

bool m_moveto;

bool m_after_moveto;

bool m_clipped;

bool m_has_init;

double m_initX, m_initY;

double m_lastx, m_lasty;

double m_origdx;

double m_origdy;

double m_origdNorm2;

double m_dnorm2ForwardMax;

double m_dnorm2BackwardMax;

bool m_lastForwardMax;

bool m_lastBackwardMax;

double m_nextX;

double m_nextY;

double m_nextBackwardX;

double m_nextBackwardY;

double m_currVecStartX;

double m_currVecStartY;

inline void _push(double *x, double *y)

{

bool needToPushBack = (m_dnorm2BackwardMax > 0.0);

/* If we observed any backward (anti-parallel) vectors, then

we need to push both forward and backward vectors. */

if (needToPushBack) {

/* If the last vector seen was the maximum in the forward direction,

then we need to push the forward after the backward. Otherwise,

the last vector seen was the maximum in the backward direction,

or somewhere in between, either way we are safe pushing forward

before backward. */

if (m_lastForwardMax) {

View remainder of file in raw view

matplotlib/src/path_converters.h at matplotlib_ppc64le_fix · ManthanIBM/matplotlib · GitHub

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