/*
* Copyright 2006 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkDashPathEffect.h"
#include "SkDashPathPriv.h"
#include "SkReadBuffer.h"
#include "SkWriteBuffer.h"
SkDashPathEffect::SkDashPathEffect(const SkScalar intervals[], int count,
SkScalar phase) {
SkASSERT(intervals);
SkASSERT(count > 1 && SkAlign2(count) == count);
fIntervals = (SkScalar*)sk_malloc_throw(sizeof(SkScalar) * count);
fCount = count;
for (int i = 0; i < count; i++) {
SkASSERT(intervals[i] >= 0);
fIntervals[i] = intervals[i];
}
// set the internal data members
SkDashPath::CalcDashParameters(phase, fIntervals, fCount, &fInitialDashLength,
&fInitialDashIndex, &fIntervalLength, &fPhase);
}
SkDashPathEffect::~SkDashPathEffect() {
sk_free(fIntervals);
}
bool SkDashPathEffect::filterPath(SkPath* dst, const SkPath& src,
SkStrokeRec* rec, const SkRect* cullRect) const {
return SkDashPath::FilterDashPath(dst, src, rec, cullRect, fIntervals, fCount,
fInitialDashLength, fInitialDashIndex, fIntervalLength);
}
// Currently asPoints is more restrictive then it needs to be. In the future
// we need to:
// allow kRound_Cap capping (could allow rotations in the matrix with this)
// allow paths to be returned
bool SkDashPathEffect::asPoints(PointData* results,
const SkPath& src,
const SkStrokeRec& rec,
const SkMatrix& matrix,
const SkRect* cullRect) const {
// width < 0 -> fill && width == 0 -> hairline so requiring width > 0 rules both out
if (fInitialDashLength < 0 || 0 >= rec.getWidth()) {
return false;
}
// TODO: this next test could be eased up. We could allow any number of
// intervals as long as all the ons match and all the offs match.
// Additionally, they do not necessarily need to be integers.
// We cannot allow arbitrary intervals since we want the returned points
// to be uniformly sized.
if (fCount != 2 ||
!SkScalarNearlyEqual(fIntervals[0], fIntervals[1]) ||
!SkScalarIsInt(fIntervals[0]) ||
!SkScalarIsInt(fIntervals[1])) {
return false;
}
SkPoint pts[2];
if (!src.isLine(pts)) {
return false;
}
// TODO: this test could be eased up to allow circles
if (SkPaint::kButt_Cap != rec.getCap()) {
return false;
}
// TODO: this test could be eased up for circles. Rotations could be allowed.
if (!matrix.rectStaysRect()) {
return false;
}
SkScalar length = SkPoint::Distance(pts[1], pts[0]);
SkVector tangent = pts[1] - pts[0];
if (tangent.isZero()) {
return false;
}
tangent.scale(SkScalarInvert(length));
// TODO: make this test for horizontal & vertical lines more robust
bool isXAxis = true;
if (SK_Scalar1 == tangent.fX || -SK_Scalar1 == tangent.fX) {
results->fSize.set(SkScalarHalf(fIntervals[0]), SkScalarHalf(rec.getWidth()));
} else if (SK_Scalar1 == tangent.fY || -SK_Scalar1 == tangent.fY) {
results->fSize.set(SkScalarHalf(rec.getWidth()), SkScalarHalf(fIntervals[0]));
isXAxis = false;
} else if (SkPaint::kRound_Cap != rec.getCap()) {
// Angled lines don't have axis-aligned boxes.
return false;
}
if (NULL != results) {
results->fFlags = 0;
SkScalar clampedInitialDashLength = SkMinScalar(length, fInitialDashLength);
if (SkPaint::kRound_Cap == rec.getCap()) {
results->fFlags |= PointData::kCircles_PointFlag;
}
results->fNumPoints = 0;
SkScalar len2 = length;
if (clampedInitialDashLength > 0 || 0 == fInitialDashIndex) {
SkASSERT(len2 >= clampedInitialDashLength);
if (0 == fInitialDashIndex) {
if (clampedInitialDashLength > 0) {
if (clampedInitialDashLength >= fIntervals[0]) {
++results->fNumPoints; // partial first dash
}
len2 -= clampedInitialDashLength;
}
len2 -= fIntervals[1]; // also skip first space
if (len2 < 0) {
len2 = 0;
}
} else {
len2 -= clampedInitialDashLength; // skip initial partial empty
}
}
int numMidPoints = SkScalarFloorToInt(SkScalarDiv(len2, fIntervalLength));
results->fNumPoints += numMidPoints;
len2 -= numMidPoints * fIntervalLength;
bool partialLast = false;
if (len2 > 0) {
if (len2 < fIntervals[0]) {
partialLast = true;
} else {
++numMidPoints;
++results->fNumPoints;
}
}
results->fPoints = new SkPoint[results->fNumPoints];
SkScalar distance = 0;
int curPt = 0;
if (clampedInitialDashLength > 0 || 0 == fInitialDashIndex) {
SkASSERT(clampedInitialDashLength <= length);
if (0 == fInitialDashIndex) {
if (clampedInitialDashLength > 0) {
// partial first block
SkASSERT(SkPaint::kRound_Cap != rec.getCap()); // can't handle partial circles
SkScalar x = pts[0].fX + SkScalarMul(tangent.fX, SkScalarHalf(clampedInitialDashLength));
SkScalar y = pts[0].fY + SkScalarMul(tangent.fY, SkScalarHalf(clampedInitialDashLength));
SkScalar halfWidth, halfHeight;
if (isXAxis) {
halfWidth = SkScalarHalf(clampedInitialDashLength);
halfHeight = SkScalarHalf(rec.getWidth());
} else {
halfWidth = SkScalarHalf(rec.getWidth());
halfHeight = SkScalarHalf(clampedInitialDashLength);
}
if (clampedInitialDashLength < fIntervals[0]) {
// This one will not be like the others
results->fFirst.addRect(x - halfWidth, y - halfHeight,
x + halfWidth, y + halfHeight);
} else {
SkASSERT(curPt < results->fNumPoints);
results->fPoints[curPt].set(x, y);
++curPt;
}
distance += clampedInitialDashLength;
}
distance += fIntervals[1]; // skip over the next blank block too
} else {
distance += clampedInitialDashLength;
}
}
if (0 != numMidPoints) {
distance += SkScalarHalf(fIntervals[0]);
for (int i = 0; i < numMidPoints; ++i) {
SkScalar x = pts[0].fX + SkScalarMul(tangent.fX, distance);
SkScalar y = pts[0].fY + SkScalarMul(tangent.fY, distance);
SkASSERT(curPt < results->fNumPoints);
results->fPoints[curPt].set(x, y);
++curPt;
distance += fIntervalLength;
}
distance -= SkScalarHalf(fIntervals[0]);
}
if (partialLast) {
// partial final block
SkASSERT(SkPaint::kRound_Cap != rec.getCap()); // can't handle partial circles
SkScalar temp = length - distance;
SkASSERT(temp < fIntervals[0]);
SkScalar x = pts[0].fX + SkScalarMul(tangent.fX, distance + SkScalarHalf(temp));
SkScalar y = pts[0].fY + SkScalarMul(tangent.fY, distance + SkScalarHalf(temp));
SkScalar halfWidth, halfHeight;
if (isXAxis) {
halfWidth = SkScalarHalf(temp);
halfHeight = SkScalarHalf(rec.getWidth());
} else {
halfWidth = SkScalarHalf(rec.getWidth());
halfHeight = SkScalarHalf(temp);
}
results->fLast.addRect(x - halfWidth, y - halfHeight,
x + halfWidth, y + halfHeight);
}
SkASSERT(curPt == results->fNumPoints);
}
return true;
}
SkPathEffect::DashType SkDashPathEffect::asADash(DashInfo* info) const {
if (info) {
if (info->fCount >= fCount && NULL != info->fIntervals) {
memcpy(info->fIntervals, fIntervals, fCount * sizeof(SkScalar));
}
info->fCount = fCount;
info->fPhase = fPhase;
}
return kDash_DashType;
}
SkFlattenable::Factory SkDashPathEffect::getFactory() const {
return CreateProc;
}
void SkDashPathEffect::flatten(SkWriteBuffer& buffer) const {
this->INHERITED::flatten(buffer);
buffer.writeScalar(fPhase);
buffer.writeScalarArray(fIntervals, fCount);
}
SkFlattenable* SkDashPathEffect::CreateProc(SkReadBuffer& buffer) {
return SkNEW_ARGS(SkDashPathEffect, (buffer));
}
SkDashPathEffect::SkDashPathEffect(SkReadBuffer& buffer) : INHERITED(buffer) {
bool useOldPic = buffer.isVersionLT(SkReadBuffer::kDashWritesPhaseIntervals_Version);
if (useOldPic) {
fInitialDashIndex = buffer.readInt();
fInitialDashLength = buffer.readScalar();
fIntervalLength = buffer.readScalar();
buffer.readBool(); // Dummy for old ScalarToFit field
} else {
fPhase = buffer.readScalar();
}
fCount = buffer.getArrayCount();
size_t allocSize = sizeof(SkScalar) * fCount;
if (buffer.validateAvailable(allocSize)) {
fIntervals = (SkScalar*)sk_malloc_throw(allocSize);
buffer.readScalarArray(fIntervals, fCount);
} else {
fIntervals = NULL;
}
if (useOldPic) {
fPhase = 0;
if (fInitialDashLength != -1) { // Signal for bad dash interval
for (int i = 0; i < fInitialDashIndex; ++i) {
fPhase += fIntervals[i];
}
fPhase += fIntervals[fInitialDashIndex] - fInitialDashLength;
}
} else {
// set the internal data members, fPhase should have been between 0 and intervalLength
// when written to buffer so no need to adjust it
SkDashPath::CalcDashParameters(fPhase, fIntervals, fCount, &fInitialDashLength,
&fInitialDashIndex, &fIntervalLength);
}
}