Repository navigation
Expand file tree
/
Copy pathpathdata.go
More file actions
447 lines (415 loc) · 12.2 KB
/
Copy pathpathdata.go
File metadata and controls
447 lines (415 loc) · 12.2 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
package svg
import (
"math"
strconvStdlib "strconv"
"github.com/tdewolff/minify/v2"
"github.com/tdewolff/parse/v2"
"github.com/tdewolff/parse/v2/strconv"
)
// PathData represents a path data string.
type PathData struct {
o *Minifier
x, y float64
x0, y0 float64
coords [][]byte
coordFloats []float64
cx, cy float64 // last control point for cubic bezier
qx, qy float64 // last control point for quadratic bezier
state PathDataState
curBuffer []byte
altBuffer []byte
coordBuffer []byte
}
// PathDataState is the state of the current path.
type PathDataState struct {
cmd byte
prevDigit bool
prevDigitIsInt bool
prevFlag bool
}
// NewPathData returns a new PathData.
func NewPathData(o *Minifier) *PathData {
return &PathData{
o: o,
cx: math.NaN(),
cy: math.NaN(),
qx: math.NaN(),
qy: math.NaN(),
}
}
var pathCmds = map[byte]bool{
'M': true,
'm': true,
'L': true,
'l': true,
'H': true,
'h': true,
'V': true,
'v': true,
'Q': true,
'q': true,
'T': true,
't': true,
'C': true,
'c': true,
'S': true,
's': true,
'A': true,
'a': true,
'Z': true,
'z': true,
}
// ShortenPathData takes a full pathdata string and returns a shortened version. The original string is overwritten.
// It parses all commands (M, A, Z, ...) and coordinates (numbers) and calls copyInstruction for each command.
func (p *PathData) ShortenPathData(b []byte) []byte {
if 100000 < len(b) {
// prevent extremely long paths for being too costly (OSS-Fuzz)
return b
}
var cmd byte
p.x, p.y = 0.0, 0.0
p.coords = p.coords[:0]
p.coordFloats = p.coordFloats[:0]
p.state = PathDataState{}
j := 0
for i := 0; i < len(b); i++ {
c := b[i]
if c == ' ' || c == ',' || c == '\n' || c == '\r' || c == '\t' {
continue
} else if pathCmds[c] && (cmd == 0 || cmd != c || c == 'M' || c == 'm') { // any command
if cmd != 0 {
j += p.copyInstruction(b[j:], cmd)
}
cmd = c
p.coords = p.coords[:0]
p.coordFloats = p.coordFloats[:0]
} else if (cmd == 'A' || cmd == 'a') && (len(p.coordFloats)%7 == 3 || len(p.coordFloats)%7 == 4) {
// boolean flags for arc command
if c == '1' {
p.coords = append(p.coords, b[i:i+1])
p.coordFloats = append(p.coordFloats, 1.0)
} else if c == '0' {
p.coords = append(p.coords, b[i:i+1])
p.coordFloats = append(p.coordFloats, 0.0)
} else {
cmd = 0 // bad format, don't minify
}
} else if n := parse.Number(b[i:]); n > 0 {
f, _ := strconv.ParseFloat(b[i : i+n])
p.coords = append(p.coords, b[i:i+n])
p.coordFloats = append(p.coordFloats, f)
i += n - 1
}
}
if cmd == 0 {
return b
}
j += p.copyInstruction(b[j:], cmd)
return b[:j]
}
// copyInstruction copies pathdata of a single command, but may be comprised of multiple sets for that command. For example, L takes two coordinates, but this function may process 2*N coordinates. Lowercase commands are relative commands, where the coordinates are relative to the previous point. Uppercase commands have absolute coordinates.
// We update p.x and p.y (the current coordinates) according to the commands given. For each set of coordinates we call shortenCurPosInstruction and shortenAltPosInstruction. The former just minifies the coordinates, the latter will inverse the lowercase/uppercase of the command, and see if the coordinates get smaller due to that. The shortest is chosen and copied to b, i.e. b is the destination and is not read from.
func (p *PathData) copyInstruction(b []byte, cmd byte) int {
n := len(p.coords)
if n == 0 {
if cmd == 'Z' || cmd == 'z' {
p.x = p.x0
p.y = p.y0
b[0] = 'z'
return 1
}
return 0
}
isRelCmd := cmd >= 'a'
// get new cursor coordinates
di := 0
if (cmd == 'M' || cmd == 'm' || cmd == 'L' || cmd == 'l' || cmd == 'T' || cmd == 't') && n%2 == 0 {
di = 2
// reprint M always, as the first pair is a move but subsequent pairs are L
if cmd == 'M' || cmd == 'm' {
p.state.cmd = byte(0)
}
} else if cmd == 'H' || cmd == 'h' || cmd == 'V' || cmd == 'v' {
di = 1
} else if (cmd == 'S' || cmd == 's' || cmd == 'Q' || cmd == 'q') && n%4 == 0 {
di = 4
} else if (cmd == 'C' || cmd == 'c') && n%6 == 0 {
di = 6
} else if (cmd == 'A' || cmd == 'a') && n%7 == 0 {
di = 7
} else {
return 0
}
j := 0
origCmd := cmd
for i := 0; i < n; i += di {
// subsequent coordinate pairs for M are really L
if i > 0 && (origCmd == 'M' || origCmd == 'm') {
origCmd = 'L' + (origCmd - 'M')
}
cmd = origCmd
coords := p.coords[i : i+di]
coordFloats := p.coordFloats[i : i+di]
// set next coordinate
var ax, ay float64
if cmd == 'H' || cmd == 'h' {<
8000
/div>
ax = coordFloats[di-1]
if isRelCmd {
ax += p.x
}
ay = p.y
} else if cmd == 'V' || cmd == 'v' {
ax = p.x
ay = coordFloats[di-1]
if isRelCmd {
ay += p.y
}
} else {
ax = coordFloats[di-2]
ay = coordFloats[di-1]
if isRelCmd {
ax += p.x
ay += p.y
}
}
// switch from C to S whenever possible
if cmd == 'C' || cmd == 'c' || cmd == 'S' || cmd == 's' {
if math.IsNaN(p.cx) {
p.cx, p.cy = p.x, p.y
} else {
p.cx, p.cy = 2*p.x-p.cx, 2*p.y-p.cy
}
var cp1x, cp1y float64
cp2x, cp2y := coordFloats[di-4], coordFloats[di-3]
if isRelCmd {
cp2x += p.x
cp2y += p.y
}
if cmd == 'C' || cmd == 'c' {
cp1x, cp1y = coordFloats[di-6], coordFloats[di-5]
if isRelCmd {
cp1x += p.x
cp1y += p.y
}
if cp1x == p.cx && cp1y == p.cy {
if isRelCmd {
cmd = 's'
} else {
cmd = 'S'
}
coords = coords[2:]
coordFloats = coordFloats[2:]
}
} else {
cp1x, cp1y = p.cx, p.cy
}
// if control points overlap begin/end points, this is a straight line
// even though if the control points would be along the straight line, we won't minify that as the control points influence the speed along the curve (important for dashes for example)
// only change to a lines if we start with s or S and none follow
if (cmd == 'C' || cmd == 'c' || i == 0 && i+di >= n) && (cp1x == p.x && cp1y == p.y || cp1x == ax && cp1y == ay) && (cp2x == p.x && cp2y == p.y || cp2x == ax && cp2y == ay) {
if isRelCmd {
cmd = 'l'
} else {
cmd = 'L'
}
coords = coords[len(coords)-2:]
coordFloats = coordFloats[len(coordFloats)-2:]
cp2x, cp2y = math.NaN(), math.NaN()
}
p.cx, p.cy = cp2x, cp2y
} else {
p.cx, p.cy = math.NaN(), math.NaN()
}
// switch from Q to T whenever possible
if cmd == 'Q' || cmd == 'q' || cmd == 'T' || cmd == 't' {
if math.IsNaN(p.qx) {
p.qx, p.qy = p.x, p.y
} else {
p.qx, p.qy = 2*p.x-p.qx, 2*p.y-p.qy
}
var cpx, cpy float64
if cmd == 'Q' || cmd == 'q' {
cpx, cpy = coordFloats[di-4], coordFloats[di-3]
if isRelCmd {
cpx += p.x
cpy += p.y
}
if cpx == p.qx && cpy == p.qy {
if isRelCmd {
cmd = 't'
} else {
cmd = 'T'
}
coords = coords[2:]
coordFloats = coordFloats[2:]
}
} else {
cpx, cpy = p.qx, p.qy
}
// if control point overlaps begin/end points, this is a straight line
// even if the control point would be along the straight line, we won't minify that as the control point influences the speed along the curve (important for dashes for example)
// only change to line if we start with t or T and none follow
if (cmd == 'Q' || cmd == 'q' || i == 0 && i+di >= n) && (cpx == p.x && cpy == p.y || cpx == ax && cpy == ay) {
if isRelCmd {
cmd = 'l'
} else {
cmd = 'L'
}
coords = coords[len(coords)-2:]
coordFloats = coordFloats[len(coordFloats)-2:]
cpx, cpy = math.NaN(), math.NaN()
}
p.qx, p.qy = cpx, cpy
} else {
p.qx, p.qy = math.NaN(), math.NaN()
}
// switch from L to H or V whenever possible
if cmd == 'L' || cmd == 'l' {
if ax == p.x && ay == p.y {
continue
} else if ax == p.x {
if isRelCmd {
cmd = 'v'
} else {
cmd = 'V'
}
coords = coords[1:]
coordFloats = coordFloats[1:]
} else if ay == p.y {
if isRelCmd {
cmd = 'h'
} else {
cmd = 'H'
}
coords = coords[:1]
coordFloats = coordFloats[:1]
}
}
// make a current and alternated path with absolute/relative altered
var curState, altState PathDataState
curState = p.shortenCurPosInstruction(cmd, coords)
if isRelCmd {
altState = p.shortenAltPosInstruction(cmd-'a'+'A', coordFloats, p.x, p.y)
} else {
altState = p.shortenAltPosInstruction(cmd-'A'+'a', coordFloats, -p.x, -p.y)
}
// choose shortest, relative or absolute path?
if len(p.altBuffer) < len(p.curBuffer) {
j += copy(b[j:], p.altBuffer)
p.state = altState
} else {
j += copy(b[j:], p.curBuffer)
p.state = curState
}
p.x = ax
p.y = ay
if i == 0 && (origCmd == 'M' || origCmd == 'm') {
p.x0 = p.x
p.y0 = p.y
}
}
return j
}
// shortenCurPosInstruction only minifies the coordinates.
func (p *PathData) shortenCurPosInstruction(cmd byte, coords [][]byte) PathDataState {
state := p.state
p.curBuffer = p.curBuffer[:0]
if cmd != state.cmd && !(state.cmd == 'M' && cmd == 'L' || state.cmd == 'm' && cmd == 'l') {
p.curBuffer = append(p.curBuffer, cmd)
state.cmd = cmd
state.prevDigit = false
state.prevDigitIsInt = false
}
for i, coord := range coords {
// Arc has boolean flags that can only be 0 or 1. copyFlag prevents from adding a dot before a zero (instead of a space). However, when the dot already was there, the command is malformed and could make the path longer than before, introducing bugs.
if (cmd == 'A' || cmd == 'a') && (i%7 == 3 || i%7 == 4) {
state.copyFlag(&p.curBuffer, coord[0] == '1')
continue
}
coord = minify.Number(coord, p.o.Precision)
state.copyNumber(&p.curBuffer, coord)
}
return state
}
// shortenAltPosInstruction toggles the command between absolute / relative coordinates and minifies the coordinates.
func (p *PathData) shortenAltPosInstruction(cmd byte, coordFloats []float64, x, y float64) PathDataState {
state := p.state
p.altBuffer = p.altBuffer[:0]
if cmd != state.cmd && !(state.cmd == 'M' && cmd == 'L' || state.cmd == 'm' && cmd == 'l') {
p.altBuffer = append(p.altBuffer, cmd)
state.cmd = cmd
state.prevDigit = false
state.prevDigitIsInt = false
}
for i, f := range coordFloats {
if cmd == 'L' || cmd == 'l' || cmd == 'C' || cmd == 'c' || cmd == 'S' || cmd == 's' || cmd == 'Q' || cmd == 'q' || cmd == 'T' || cmd == 't' || cmd == 'M' || cmd == 'm' {
if i%2 == 0 {
f += x
} else {
f += y
}
} else if cmd == 'H' || cmd == 'h' {
f += x
} else if cmd == 'V' || cmd == 'v' {
f += y
} else if cmd == 'A' || cmd == 'a' {
if i%7 == 5 {
f += x
} else if i%7 == 6 {
f += y
} else if i%7 == 3 || i%7 == 4 {
state.copyFlag(&p.altBuffer, f == 1.0)
continue
}
}
p.coordBuffer = strconvStdlib.AppendFloat(p.coordBuffer[:0], f, 'g', -1, 64)
coord := minify.Number(p.coordBuffer, p.o.newPrecision)
state.copyNumber(&p.altBuffer, coord)
}
return state
}
// copyNumber will copy a number to the destination buffer, taking into account space or dot insertion to guarantee the shortest pathdata.
func (state *PathDataState) copyNumber(buffer *[]byte, coord []byte) {
if state.prevDigit && (coord[0] >= '0' && coord[0] <= '9' || coord[0] == '.' && state.prevDigitIsInt) {
if coord[0] == '0' && !state.prevDigitIsInt {
*buffer = append(*buffer, '.', '0') // aggresively add dot so subsequent numbers could drop leading space
// prevDigit stays true and prevDigitIsInt stays false
return
}
*buffer = append(*buffer, ' ')
}
state.prevDigit = true
state.prevDigitIsInt = true
if len(coord) > 2 && coord[len(coord)-2] == '0' && coord[len(coord)-1] == '0' {
coord[len(coord)-2] = 'e'
coord[len(coord)-1] = '2'
state.prevDigitIsInt = false
} else {
for _, c := range coord {
if c == '.' || c == 'e' || c == 'E' {
state.prevDigitIsInt = false
break
}
}
}
*buffer = append(*buffer, coord...)
state.prevFlag = false
}
func (state *PathDataState) copyFlag(buffer *[]byte, flag bool) {
if !state.prevFlag {
if flag {
*buffer = append(*buffer, ' ', '1')
} else {
*buffer = append(*buffer, ' ', '0')
}
} else {
if flag {
*buffer = append(*buffer, '1')
} else {
*buffer = append(*buffer, '0')
}
}
state.prevFlag = true
state.prevDigit = false
state.prevDigitIsInt = false
}