VectorDrawable.cpp revision 46591f4a2dbd785bcae2b82bb490e78208605ec8 
1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "VectorDrawable.h"
18
19#include "PathParser.h"
20#include "SkImageInfo.h"
21#include "SkShader.h"
22#include <utils/Log.h>
23#include "utils/Macros.h"
24#include "utils/VectorDrawableUtils.h"
25
26#include <math.h>
27#include <string.h>
28
29namespace android {
30namespace uirenderer {
31namespace VectorDrawable {
32
33const int Tree::MAX_CACHED_BITMAP_SIZE = 2048;
34
35void Path::draw(SkCanvas* outCanvas, const SkMatrix& groupStackedMatrix, float scaleX, float scaleY) {
36    float matrixScale = getMatrixScale(groupStackedMatrix);
37    if (matrixScale == 0) {
38        // When either x or y is scaled to 0, we don't need to draw anything.
39        return;
40    }
41
42    const SkPath updatedPath = getUpdatedPath();
43    SkMatrix pathMatrix(groupStackedMatrix);
44    pathMatrix.postScale(scaleX, scaleY);
45
46    //TODO: try apply the path matrix to the canvas instead of creating a new path.
47    SkPath renderPath;
48    renderPath.reset();
49    renderPath.addPath(updatedPath, pathMatrix);
50
51    float minScale = fmin(scaleX, scaleY);
52    float strokeScale = minScale * matrixScale;
53    drawPath(outCanvas, renderPath, strokeScale, pathMatrix);
54}
55
56void Path::setPathData(const Data& data) {
57    if (mData == data) {
58        return;
59    }
60    // Updates the path data. Note that we don't generate a new Skia path right away
61    // because there are cases where the animation is changing the path data, but the view
62    // that hosts the VD has gone off screen, in which case we won't even draw. So we
63    // postpone the Skia path generation to the draw time.
64    mData = data;
65    mSkPathDirty = true;
66}
67
68void Path::dump() {
69    ALOGD("Path: %s has %zu points", mName.c_str(), mData.points.size());
70}
71
72float Path::getMatrixScale(const SkMatrix& groupStackedMatrix) {
73    // Given unit vectors A = (0, 1) and B = (1, 0).
74    // After matrix mapping, we got A' and B'. Let theta = the angel b/t A' and B'.
75    // Therefore, the final scale we want is min(|A'| * sin(theta), |B'| * sin(theta)),
76    // which is (|A'| * |B'| * sin(theta)) / max (|A'|, |B'|);
77    // If  max (|A'|, |B'|) = 0, that means either x or y has a scale of 0.
78    //
79    // For non-skew case, which is most of the cases, matrix scale is computing exactly the
80    // scale on x and y axis, and take the minimal of these two.
81    // For skew case, an unit square will mapped to a parallelogram. And this function will
82    // return the minimal height of the 2 bases.
83    SkVector skVectors[2];
84    skVectors[0].set(0, 1);
85    skVectors[1].set(1, 0);
86    groupStackedMatrix.mapVectors(skVectors, 2);
87    float scaleX = hypotf(skVectors[0].fX, skVectors[0].fY);
88    float scaleY = hypotf(skVectors[1].fX, skVectors[1].fY);
89    float crossProduct = skVectors[0].cross(skVectors[1]);
90    float maxScale = fmax(scaleX, scaleY);
91
92    float matrixScale = 0;
93    if (maxScale > 0) {
94        matrixScale = fabs(crossProduct) / maxScale;
95    }
96    return matrixScale;
97}
98Path::Path(const char* pathStr, size_t strLength) {
99    PathParser::ParseResult result;
100    PathParser::getPathDataFromString(&mData, &result, pathStr, strLength);
101    if (!result.failureOccurred) {
102        VectorDrawableUtils::verbsToPath(&mSkPath, mData);
103    }
104}
105
106Path::Path(const Data& data) {
107    mData = data;
108    // Now we need to construct a path
109    VectorDrawableUtils::verbsToPath(&mSkPath, data);
110}
111
112Path::Path(const Path& path) : Node(path) {
113    mData = path.mData;
114    VectorDrawableUtils::verbsToPath(&mSkPath, mData);
115}
116
117bool Path::canMorph(const Data& morphTo) {
118    return VectorDrawableUtils::canMorph(mData, morphTo);
119}
120
121bool Path::canMorph(const Path& path) {
122    return canMorph(path.mData);
123}
124
125const SkPath& Path::getUpdatedPath() {
126    if (mSkPathDirty) {
127        mSkPath.reset();
128        VectorDrawableUtils::verbsToPath(&mSkPath, mData);
129        mSkPathDirty = false;
130    }
131    return mSkPath;
132}
133
134void Path::setPath(const char* pathStr, size_t strLength) {
135    PathParser::ParseResult result;
136    mSkPathDirty = true;
137    PathParser::getPathDataFromString(&mData, &result, pathStr, strLength);
138}
139
140FullPath::FullPath(const FullPath& path) : Path(path) {
141    mProperties = path.mProperties;
142    SkRefCnt_SafeAssign(mStrokeGradient, path.mStrokeGradient);
143    SkRefCnt_SafeAssign(mFillGradient, path.mFillGradient);
144}
145
146const SkPath& FullPath::getUpdatedPath() {
147    if (!mSkPathDirty && !mTrimDirty) {
148        return mTrimmedSkPath;
149    }
150    Path::getUpdatedPath();
151    if (mProperties.trimPathStart != 0.0f || mProperties.trimPathEnd != 1.0f) {
152        applyTrim();
153        return mTrimmedSkPath;
154    } else {
155        return mSkPath;
156    }
157}
158
159void FullPath::updateProperties(float strokeWidth, SkColor strokeColor, float strokeAlpha,
160        SkColor fillColor, float fillAlpha, float trimPathStart, float trimPathEnd,
161        float trimPathOffset, float strokeMiterLimit, int strokeLineCap, int strokeLineJoin,
162        int fillType) {
163    mProperties.strokeWidth = strokeWidth;
164    mProperties.strokeColor = strokeColor;
165    mProperties.strokeAlpha = strokeAlpha;
166    mProperties.fillColor = fillColor;
167    mProperties.fillAlpha = fillAlpha;
168    mProperties.strokeMiterLimit = strokeMiterLimit;
169    mProperties.strokeLineCap = strokeLineCap;
170    mProperties.strokeLineJoin = strokeLineJoin;
171    mProperties.fillType = fillType;
172
173    // If any trim property changes, mark trim dirty and update the trim path
174    setTrimPathStart(trimPathStart);
175    setTrimPathEnd(trimPathEnd);
176    setTrimPathOffset(trimPathOffset);
177}
178
179inline SkColor applyAlpha(SkColor color, float alpha) {
180    int alphaBytes = SkColorGetA(color);
181    return SkColorSetA(color, alphaBytes * alpha);
182}
183
184void FullPath::drawPath(SkCanvas* outCanvas, SkPath& renderPath, float strokeScale,
185                        const SkMatrix& matrix){
186    // Draw path's fill, if fill color or gradient is valid
187    bool needsFill = false;
188    if (mFillGradient != nullptr) {
189        mPaint.setColor(applyAlpha(SK_ColorBLACK, mProperties.fillAlpha));
190        SkShader* newShader = mFillGradient->newWithLocalMatrix(matrix);
191        mPaint.setShader(newShader);
192        needsFill = true;
193    } else if (mProperties.fillColor != SK_ColorTRANSPARENT) {
194        mPaint.setColor(applyAlpha(mProperties.fillColor, mProperties.fillAlpha));
195        needsFill = true;
196    }
197
198    if (needsFill) {
199        mPaint.setStyle(SkPaint::Style::kFill_Style);
200        mPaint.setAntiAlias(true);
201        SkPath::FillType ft = static_cast<SkPath::FillType>(mProperties.fillType);
202        renderPath.setFillType(ft);
203        outCanvas->drawPath(renderPath, mPaint);
204    }
205
206    // Draw path's stroke, if stroke color or gradient is valid
207    bool needsStroke = false;
208    if (mStrokeGradient != nullptr) {
209        mPaint.setColor(applyAlpha(SK_ColorBLACK, mProperties.strokeAlpha));
210        SkShader* newShader = mStrokeGradient->newWithLocalMatrix(matrix);
211        mPaint.setShader(newShader);
212        needsStroke = true;
213    } else if (mProperties.strokeColor != SK_ColorTRANSPARENT) {
214        mPaint.setColor(applyAlpha(mProperties.strokeColor, mProperties.strokeAlpha));
215        needsStroke = true;
216    }
217    if (needsStroke) {
218        mPaint.setStyle(SkPaint::Style::kStroke_Style);
219        mPaint.setAntiAlias(true);
220        mPaint.setStrokeJoin(SkPaint::Join(mProperties.strokeLineJoin));
221        mPaint.setStrokeCap(SkPaint::Cap(mProperties.strokeLineCap));
222        mPaint.setStrokeMiter(mProperties.strokeMiterLimit);
223        mPaint.setStrokeWidth(mProperties.strokeWidth * strokeScale);
224        outCanvas->drawPath(renderPath, mPaint);
225    }
226}
227
228/**
229 * Applies trimming to the specified path.
230 */
231void FullPath::applyTrim() {
232    if (mProperties.trimPathStart == 0.0f && mProperties.trimPathEnd == 1.0f) {
233        // No trimming necessary.
234        return;
235    }
236    SkPathMeasure measure(mSkPath, false);
237    float len = SkScalarToFloat(measure.getLength());
238    float start = len * fmod((mProperties.trimPathStart + mProperties.trimPathOffset), 1.0f);
239    float end = len * fmod((mProperties.trimPathEnd + mProperties.trimPathOffset), 1.0f);
240
241    mTrimmedSkPath.reset();
242    if (start > end) {
243        measure.getSegment(start, len, &mTrimmedSkPath, true);
244        measure.getSegment(0, end, &mTrimmedSkPath, true);
245    } else {
246        measure.getSegment(start, end, &mTrimmedSkPath, true);
247    }
248    mTrimDirty = false;
249}
250
251REQUIRE_COMPATIBLE_LAYOUT(FullPath::Properties);
252
253static_assert(sizeof(float) == sizeof(int32_t), "float is not the same size as int32_t");
254static_assert(sizeof(SkColor) == sizeof(int32_t), "SkColor is not the same size as int32_t");
255
256bool FullPath::getProperties(int8_t* outProperties, int length) {
257    int propertyDataSize = sizeof(Properties);
258    if (length != propertyDataSize) {
259        LOG_ALWAYS_FATAL("Properties needs exactly %d bytes, a byte array of size %d is provided",
260                propertyDataSize, length);
261        return false;
262    }
263    Properties* out = reinterpret_cast<Properties*>(outProperties);
264    *out = mProperties;
265    return true;
266}
267
268void FullPath::setColorPropertyValue(int propertyId, int32_t value) {
269    Property currentProperty = static_cast<Property>(propertyId);
270    if (currentProperty == Property::StrokeColor) {
271        mProperties.strokeColor = value;
272    } else if (currentProperty == Property::FillColor) {
273        mProperties.fillColor = value;
274    } else {
275        LOG_ALWAYS_FATAL("Error setting color property on FullPath: No valid property with id: %d",
276                propertyId);
277    }
278}
279
280void FullPath::setPropertyValue(int propertyId, float value) {
281    Property property = static_cast<Property>(propertyId);
282    switch (property) {
283    case Property::StrokeWidth:
284        setStrokeWidth(value);
285        break;
286    case Property::StrokeAlpha:
287        setStrokeAlpha(value);
288        break;
289    case Property::FillAlpha:
290        setFillAlpha(value);
291        break;
292    case Property::TrimPathStart:
293        setTrimPathStart(value);
294        break;
295    case Property::TrimPathEnd:
296        setTrimPathEnd(value);
297        break;
298    case Property::TrimPathOffset:
299        setTrimPathOffset(value);
300        break;
301    default:
302        LOG_ALWAYS_FATAL("Invalid property id: %d for animation", propertyId);
303        break;
304    }
305}
306
307void ClipPath::drawPath(SkCanvas* outCanvas, SkPath& renderPath,
308        float strokeScale, const SkMatrix& matrix){
309    outCanvas->clipPath(renderPath, SkRegion::kIntersect_Op);
310}
311
312Group::Group(const Group& group) : Node(group) {
313    mProperties = group.mProperties;
314}
315
316void Group::draw(SkCanvas* outCanvas, const SkMatrix& currentMatrix, float scaleX,
317        float scaleY) {
318    // TODO: Try apply the matrix to the canvas instead of passing it down the tree
319
320    // Calculate current group's matrix by preConcat the parent's and
321    // and the current one on the top of the stack.
322    // Basically the Mfinal = Mviewport * M0 * M1 * M2;
323    // Mi the local matrix at level i of the group tree.
324    SkMatrix stackedMatrix;
325    getLocalMatrix(&stackedMatrix);
326    stackedMatrix.postConcat(currentMatrix);
327
328    // Save the current clip information, which is local to this group.
329    outCanvas->save();
330    // Draw the group tree in the same order as the XML file.
331    for (auto& child : mChildren) {
332        child->draw(outCanvas, stackedMatrix, scaleX, scaleY);
333    }
334    // Restore the previous clip information.
335    outCanvas->restore();
336}
337
338void Group::dump() {
339    ALOGD("Group %s has %zu children: ", mName.c_str(), mChildren.size());
340    for (size_t i = 0; i < mChildren.size(); i++) {
341        mChildren[i]->dump();
342    }
343}
344
345void Group::updateLocalMatrix(float rotate, float pivotX, float pivotY,
346        float scaleX, float scaleY, float translateX, float translateY) {
347    setRotation(rotate);
348    setPivotX(pivotX);
349    setPivotY(pivotY);
350    setScaleX(scaleX);
351    setScaleY(scaleY);
352    setTranslateX(translateX);
353    setTranslateY(translateY);
354}
355
356void Group::getLocalMatrix(SkMatrix* outMatrix) {
357    outMatrix->reset();
358    // TODO: use rotate(mRotate, mPivotX, mPivotY) and scale with pivot point, instead of
359    // translating to pivot for rotating and scaling, then translating back.
360    outMatrix->postTranslate(-mProperties.pivotX, -mProperties.pivotY);
361    outMatrix->postScale(mProperties.scaleX, mProperties.scaleY);
362    outMatrix->postRotate(mProperties.rotate, 0, 0);
363    outMatrix->postTranslate(mProperties.translateX + mProperties.pivotX,
364            mProperties.translateY + mProperties.pivotY);
365}
366
367void Group::addChild(Node* child) {
368    mChildren.emplace_back(child);
369}
370
371bool Group::getProperties(float* outProperties, int length) {
372    int propertyCount = static_cast<int>(Property::Count);
373    if (length != propertyCount) {
374        LOG_ALWAYS_FATAL("Properties needs exactly %d bytes, a byte array of size %d is provided",
375                propertyCount, length);
376        return false;
377    }
378    Properties* out = reinterpret_cast<Properties*>(outProperties);
379    *out = mProperties;
380    return true;
381}
382
383// TODO: Consider animating the properties as float pointers
384float Group::getPropertyValue(int propertyId) const {
385    Property currentProperty = static_cast<Property>(propertyId);
386    switch (currentProperty) {
387    case Property::Rotate:
388        return mProperties.rotate;
389    case Property::PivotX:
390        return mProperties.pivotX;
391    case Property::PivotY:
392        return mProperties.pivotY;
393    case Property::ScaleX:
394        return mProperties.scaleX;
395    case Property::ScaleY:
396        return mProperties.scaleY;
397    case Property::TranslateX:
398        return mProperties.translateX;
399    case Property::TranslateY:
400        return mProperties.translateY;
401    default:
402        LOG_ALWAYS_FATAL("Invalid property index: %d", propertyId);
403        return 0;
404    }
405}
406
407void Group::setPropertyValue(int propertyId, float value) {
408    Property currentProperty = static_cast<Property>(propertyId);
409    switch (currentProperty) {
410    case Property::Rotate:
411        mProperties.rotate = value;
412        break;
413    case Property::PivotX:
414        mProperties.pivotX = value;
415        break;
416    case Property::PivotY:
417        mProperties.pivotY = value;
418        break;
419    case Property::ScaleX:
420        mProperties.scaleX = value;
421        break;
422    case Property::ScaleY:
423        mProperties.scaleY = value;
424        break;
425    case Property::TranslateX:
426        mProperties.translateX = value;
427        break;
428    case Property::TranslateY:
429        mProperties.translateY = value;
430        break;
431    default:
432        LOG_ALWAYS_FATAL("Invalid property index: %d", propertyId);
433    }
434}
435
436bool Group::isValidProperty(int propertyId) {
437    return propertyId >= 0 && propertyId < static_cast<int>(Property::Count);
438}
439
440void Tree::draw(Canvas* outCanvas, SkColorFilter* colorFilter,
441        const SkRect& bounds, bool needsMirroring, bool canReuseCache) {
442    // The imageView can scale the canvas in different ways, in order to
443    // avoid blurry scaling, we have to draw into a bitmap with exact pixel
444    // size first. This bitmap size is determined by the bounds and the
445    // canvas scale.
446    outCanvas->getMatrix(&mCanvasMatrix);
447    mBounds = bounds;
448    float canvasScaleX = 1.0f;
449    float canvasScaleY = 1.0f;
450    if (mCanvasMatrix.getSkewX() == 0 && mCanvasMatrix.getSkewY() == 0) {
451        // Only use the scale value when there's no skew or rotation in the canvas matrix.
452        // TODO: Add a cts test for drawing VD on a canvas with negative scaling factors.
453        canvasScaleX = fabs(mCanvasMatrix.getScaleX());
454        canvasScaleY = fabs(mCanvasMatrix.getScaleY());
455    }
456    int scaledWidth = (int) (mBounds.width() * canvasScaleX);
457    int scaledHeight = (int) (mBounds.height() * canvasScaleY);
458    scaledWidth = std::min(Tree::MAX_CACHED_BITMAP_SIZE, scaledWidth);
459    scaledHeight = std::min(Tree::MAX_CACHED_BITMAP_SIZE, scaledHeight);
460
461    if (scaledWidth <= 0 || scaledHeight <= 0) {
462        return;
463    }
464
465    mPaint.setColorFilter(colorFilter);
466
467    int saveCount = outCanvas->save(SaveFlags::MatrixClip);
468    outCanvas->translate(mBounds.fLeft, mBounds.fTop);
469
470    // Handle RTL mirroring.
471    if (needsMirroring) {
472        outCanvas->translate(mBounds.width(), 0);
473        outCanvas->scale(-1.0f, 1.0f);
474    }
475
476    // At this point, canvas has been translated to the right position.
477    // And we use this bound for the destination rect for the drawBitmap, so
478    // we offset to (0, 0);
479    mBounds.offsetTo(0, 0);
480    createCachedBitmapIfNeeded(scaledWidth, scaledHeight);
481
482    outCanvas->drawVectorDrawable(this);
483
484    outCanvas->restoreToCount(saveCount);
485}
486
487SkPaint* Tree::getPaint() {
488    SkPaint* paint;
489    if (mRootAlpha == 1.0f && mPaint.getColorFilter() == NULL) {
490        paint = NULL;
491    } else {
492        mPaint.setFilterQuality(kLow_SkFilterQuality);
493        mPaint.setAlpha(mRootAlpha * 255);
494        paint = &mPaint;
495    }
496    return paint;
497}
498
499const SkBitmap& Tree::getBitmapUpdateIfDirty() {
500    mCachedBitmap.eraseColor(SK_ColorTRANSPARENT);
501    SkCanvas outCanvas(mCachedBitmap);
502    float scaleX = (float) mCachedBitmap.width() / mViewportWidth;
503    float scaleY = (float) mCachedBitmap.height() / mViewportHeight;
504    mRootNode->draw(&outCanvas, SkMatrix::I(), scaleX, scaleY);
505    mCacheDirty = false;
506    return mCachedBitmap;
507}
508
509void Tree::createCachedBitmapIfNeeded(int width, int height) {
510    if (!canReuseBitmap(width, height)) {
511        SkImageInfo info = SkImageInfo::Make(width, height,
512                kN32_SkColorType, kPremul_SkAlphaType);
513        mCachedBitmap.setInfo(info);
514        // TODO: Count the bitmap cache against app's java heap
515        mCachedBitmap.allocPixels(info);
516        mCacheDirty = true;
517    }
518}
519
520bool Tree::canReuseBitmap(int width, int height) {
521    return width == mCachedBitmap.width() && height == mCachedBitmap.height();
522}
523
524}; // namespace VectorDrawable
525
526}; // namespace uirenderer
527}; // namespace android
528