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/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkParse.h"
#include "SkParsePath.h"
static inline bool is_between(int c, int min, int max) {
return (unsigned)(c - min) <= (unsigned)(max - min);
}
static inline bool is_ws(int c) {
return is_between(c, 1, 32);
}
static inline bool is_digit(int c) {
return is_between(c, '0', '9');
}
static inline bool is_sep(int c) {
return is_ws(c) || c == ',';
}
static inline bool is_lower(int c) {
return is_between(c, 'a', 'z');
}
static inline int to_upper(int c) {
return c - 'a' + 'A';
}
static const char* skip_ws(const char str[]) {
SkASSERT(str);
while (is_ws(*str))
str++;
return str;
}
static const char* skip_sep(const char str[]) {
SkASSERT(str);
while (is_sep(*str))
str++;
return str;
}
static const char* find_points(const char str[], SkPoint value[], int count,
bool isRelative, SkPoint* relative) {
str = SkParse::FindScalars(str, &value[0].fX, count * 2);
if (isRelative) {
for (int index = 0; index < count; index++) {
value[index].fX += relative->fX;
value[index].fY += relative->fY;
}
}
return str;
}
static const char* find_scalar(const char str[], SkScalar* value,
bool isRelative, SkScalar relative) {
str = SkParse::FindScalar(str, value);
if (isRelative) {
*value += relative;
}
return str;
}
bool SkParsePath::FromSVGString(const char data[], SkPath* result) {
SkPath path;
SkPoint f = {0, 0};
SkPoint c = {0, 0};
SkPoint lastc = {0, 0};
SkPoint points[3];
char op = '\0';
char previousOp = '\0';
bool relative = false;
for (;;) {
data = skip_ws(data);
if (data[0] == '\0') {
break;
}
char ch = data[0];
if (is_digit(ch) || ch == '-' || ch == '+') {
if (op == '\0') {
return false;
}
} else if (is_sep(ch)) {
data = skip_sep(data);
} else {
op = ch;
relative = false;
if (is_lower(op)) {
op = (char) to_upper(op);
relative = true;
}
data++;
data = skip_sep(data);
}
switch (op) {
case 'M':
data = find_points(data, points, 1, relative, &c);
path.moveTo(points[0]);
op = 'L';
c = points[0];
break;
case 'L':
data = find_points(data, points, 1, relative, &c);
path.lineTo(points[0]);
c = points[0];
break;
case 'H': {
SkScalar x;
data = find_scalar(data, &x, relative, c.fX);
path.lineTo(x, c.fY);
c.fX = x;
} break;
case 'V': {
SkScalar y;
data = find_scalar(data, &y, relative, c.fY);
path.lineTo(c.fX, y);
c.fY = y;
} break;
case 'C':
data = find_points(data, points, 3, relative, &c);
goto cubicCommon;
case 'S':
data = find_points(data, &points[1], 2, relative, &c);
points[0] = c;
if (previousOp == 'C' || previousOp == 'S') {
points[0].fX -= lastc.fX - c.fX;
points[0].fY -= lastc.fY - c.fY;
}
cubicCommon:
path.cubicTo(points[0], points[1], points[2]);
lastc = points[1];
c = points[2];
break;
case 'Q': // Quadratic Bezier Curve
data = find_points(data, points, 2, relative, &c);
goto quadraticCommon;
case 'T':
data = find_points(data, &points[1], 1, relative, &c);
points[0] = points[1];
if (previousOp == 'Q' || previousOp == 'T') {
points[0].fX = c.fX * 2 - lastc.fX;
points[0].fY = c.fY * 2 - lastc.fY;
}
quadraticCommon:
path.quadTo(points[0], points[1]);
lastc = points[0];
c = points[1];
break;
case 'Z':
path.close();
#if 0 // !!! still a bug?
if (fPath.isEmpty() && (f.fX != 0 || f.fY != 0)) {
c.fX -= SkScalar.Epsilon; // !!! enough?
fPath.moveTo(c);
fPath.lineTo(f);
fPath.close();
}
#endif
c = f;
op = '\0';
break;
case '~': {
SkPoint args[2];
data = find_points(data, args, 2, false, NULL);
path.moveTo(args[0].fX, args[0].fY);
path.lineTo(args[1].fX, args[1].fY);
} break;
default:
return false;
}
if (previousOp == 0) {
f = c;
}
previousOp = op;
}
// we're good, go ahead and swap in the result
result->swap(path);
return true;
}
///////////////////////////////////////////////////////////////////////////////
#include "SkGeometry.h"
#include "SkString.h"
#include "SkStream.h"
static void write_scalar(SkWStream* stream, SkScalar value) {
char buffer[64];
#ifdef SK_BUILD_FOR_WIN32
int len = _snprintf(buffer, sizeof(buffer), "%g", value);
#else
int len = snprintf(buffer, sizeof(buffer), "%g", value);
#endif
char* stop = buffer + len;
stream->write(buffer, stop - buffer);
}
static void append_scalars(SkWStream* stream, char verb, const SkScalar data[],
int count) {
stream->write(&verb, 1);
write_scalar(stream, data[0]);
for (int i = 1; i < count; i++) {
stream->write(" ", 1);
write_scalar(stream, data[i]);
}
}
void SkParsePath::ToSVGString(const SkPath& path, SkString* str) {
SkDynamicMemoryWStream stream;
SkPath::Iter iter(path, false);
SkPoint pts[4];
for (;;) {
switch (iter.next(pts, false)) {
case SkPath::kConic_Verb: {
const SkScalar tol = SK_Scalar1 / 1024; // how close to a quad
SkAutoConicToQuads quadder;
const SkPoint* quadPts = quadder.computeQuads(pts, iter.conicWeight(), tol);
for (int i = 0; i < quadder.countQuads(); ++i) {
append_scalars(&stream, 'Q', &quadPts[i*2 + 1].fX, 4);
}
} break;
case SkPath::kMove_Verb:
append_scalars(&stream, 'M', &pts[0].fX, 2);
break;
case SkPath::kLine_Verb:
append_scalars(&stream, 'L', &pts[1].fX, 2);
break;
case SkPath::kQuad_Verb:
append_scalars(&stream, 'Q', &pts[1].fX, 4);
break;
case SkPath::kCubic_Verb:
append_scalars(&stream, 'C', &pts[1].fX, 6);
break;
case SkPath::kClose_Verb:
stream.write("Z", 1);
break;
case SkPath::kDone_Verb:
str->resize(stream.getOffset());
stream.copyTo(str->writable_str());
return;
}
}
}
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