void SkOffsetImageFilter::onFilterNodeBounds(const SkIRect& src, const SkMatrix& ctm,
SkIRect* dst, MapDirection direction) const {
SkVector vec;
ctm.mapVectors(&vec, &fOffset, 1);
if (kReverse_MapDirection == direction) {
vec.negate();
}
*dst = src;
dst->offset(SkScalarCeilToInt(vec.fX), SkScalarCeilToInt(vec.fY));
}
static void RoundJoiner(SkPath* outer, SkPath* inner, const SkVector& beforeUnitNormal,
const SkPoint& pivot, const SkVector& afterUnitNormal,
SkScalar radius, SkScalar invMiterLimit, bool, bool)
{
SkScalar dotProd = SkPoint::DotProduct(beforeUnitNormal, afterUnitNormal);
AngleType angleType = Dot2AngleType(dotProd);
if (angleType == kNearlyLine_AngleType)
return;
SkVector before = beforeUnitNormal;
SkVector after = afterUnitNormal;
SkRotationDirection dir = kCW_SkRotationDirection;
if (!is_clockwise(before, after))
{
SkTSwap<SkPath*>(outer, inner);
before.negate();
after.negate();
dir = kCCW_SkRotationDirection;
}
SkPoint pts[kSkBuildQuadArcStorage];
SkMatrix matrix;
matrix.setScale(radius, radius);
matrix.postTranslate(pivot.fX, pivot.fY);
int count = SkBuildQuadArc(before, after, dir, &matrix, pts);
SkASSERT((count & 1) == 1);
if (count > 1)
{
for (int i = 1; i < count; i += 2)
outer->quadTo(pts[i].fX, pts[i].fY, pts[i+1].fX, pts[i+1].fY);
after.scale(radius);
HandleInnerJoin(inner, pivot, after);
}
}
void SkOffsetImageFilter::onFilterNodeBounds(const SkIRect& src, const SkMatrix& ctm,
SkIRect* dst, MapDirection direction) const {
SkVector vec;
ctm.mapVectors(&vec, &fOffset, 1);
if (kReverse_MapDirection == direction) {
vec.negate();
}
*dst = src;
dst->offset(SkScalarCeilToInt(vec.fX), SkScalarCeilToInt(vec.fY));
#ifdef SK_SUPPORT_SRC_BOUNDS_BLOAT_FOR_IMAGEFILTERS
dst->join(src);
#endif
}
static void BluntJoiner(SkPath* outer, SkPath* inner, const SkVector& beforeUnitNormal,
const SkPoint& pivot, const SkVector& afterUnitNormal,
SkScalar radius, SkScalar invMiterLimit, bool, bool)
{
SkVector after;
afterUnitNormal.scale(radius, &after);
if (!is_clockwise(beforeUnitNormal, afterUnitNormal))
{
SkTSwap<SkPath*>(outer, inner);
after.negate();
}
outer->lineTo(pivot.fX + after.fX, pivot.fY + after.fY);
HandleInnerJoin(inner, pivot, after);
}
void SkDropShadowImageFilter::onFilterNodeBounds(const SkIRect& src, const SkMatrix& ctm,
SkIRect* dst, MapDirection direction) const {
*dst = src;
SkVector offsetVec = SkVector::Make(fDx, fDy);
if (kReverse_MapDirection == direction) {
offsetVec.negate();
}
ctm.mapVectors(&offsetVec, 1);
dst->offset(SkScalarCeilToInt(offsetVec.x()),
SkScalarCeilToInt(offsetVec.y()));
SkVector sigma = SkVector::Make(fSigmaX, fSigmaY);
ctm.mapVectors(&sigma, 1);
dst->outset(SkScalarCeilToInt(SkScalarMul(sigma.x(), SkIntToScalar(3))),
SkScalarCeilToInt(SkScalarMul(sigma.y(), SkIntToScalar(3))));
if (fShadowMode == kDrawShadowAndForeground_ShadowMode) {
dst->join(src);
}
}
SkIRect SkDropShadowImageFilter::onFilterNodeBounds(const SkIRect& src, const SkMatrix& ctm,
MapDirection direction) const {
SkVector offsetVec = SkVector::Make(fDx, fDy);
if (kReverse_MapDirection == direction) {
offsetVec.negate();
}
ctm.mapVectors(&offsetVec, 1);
SkIRect dst = src.makeOffset(SkScalarCeilToInt(offsetVec.x()),
SkScalarCeilToInt(offsetVec.y()));
SkVector sigma = SkVector::Make(fSigmaX, fSigmaY);
ctm.mapVectors(&sigma, 1);
dst.outset(
SkScalarCeilToInt(SkScalarAbs(sigma.x() * 3)),
SkScalarCeilToInt(SkScalarAbs(sigma.y() * 3)));
if (fShadowMode == kDrawShadowAndForeground_ShadowMode) {
dst.join(src);
}
return dst;
}
static void bloat_quad(const SkPoint qpts[3], const SkMatrix* toDevice,
const SkMatrix* toSrc, BezierVertex verts[kQuadNumVertices]) {
SkASSERT(!toDevice == !toSrc);
// original quad is specified by tri a,b,c
SkPoint a = qpts[0];
SkPoint b = qpts[1];
SkPoint c = qpts[2];
if (toDevice) {
toDevice->mapPoints(&a, 1);
toDevice->mapPoints(&b, 1);
toDevice->mapPoints(&c, 1);
}
// make a new poly where we replace a and c by a 1-pixel wide edges orthog
// to edges ab and bc:
//
// before | after
// | b0
// b |
// |
// | a0 c0
// a c | a1 c1
//
// edges a0->b0 and b0->c0 are parallel to original edges a->b and b->c,
// respectively.
BezierVertex& a0 = verts[0];
BezierVertex& a1 = verts[1];
BezierVertex& b0 = verts[2];
BezierVertex& c0 = verts[3];
BezierVertex& c1 = verts[4];
SkVector ab = b;
ab -= a;
SkVector ac = c;
ac -= a;
SkVector cb = b;
cb -= c;
// We should have already handled degenerates
SkASSERT(ab.length() > 0 && cb.length() > 0);
ab.normalize();
SkVector abN;
abN.setOrthog(ab, SkVector::kLeft_Side);
if (abN.dot(ac) > 0) {
abN.negate();
}
cb.normalize();
SkVector cbN;
cbN.setOrthog(cb, SkVector::kLeft_Side);
if (cbN.dot(ac) < 0) {
cbN.negate();
}
a0.fPos = a;
a0.fPos += abN;
a1.fPos = a;
a1.fPos -= abN;
c0.fPos = c;
c0.fPos += cbN;
c1.fPos = c;
c1.fPos -= cbN;
intersect_lines(a0.fPos, abN, c0.fPos, cbN, &b0.fPos);
if (toSrc) {
toSrc->mapPointsWithStride(&verts[0].fPos, sizeof(BezierVertex), kQuadNumVertices);
}
}
static void MiterJoiner(SkPath* outer, SkPath* inner, const SkVector& beforeUnitNormal,
const SkPoint& pivot, const SkVector& afterUnitNormal,
SkScalar radius, SkScalar invMiterLimit,
bool prevIsLine, bool currIsLine)
{
// negate the dot since we're using normals instead of tangents
SkScalar dotProd = SkPoint::DotProduct(beforeUnitNormal, afterUnitNormal);
AngleType angleType = Dot2AngleType(dotProd);
SkVector before = beforeUnitNormal;
SkVector after = afterUnitNormal;
SkVector mid;
SkScalar sinHalfAngle;
bool ccw;
if (angleType == kNearlyLine_AngleType)
return;
if (angleType == kNearly180_AngleType)
{
currIsLine = false;
goto DO_BLUNT;
}
ccw = !is_clockwise(before, after);
if (ccw)
{
SkTSwap<SkPath*>(outer, inner);
before.negate();
after.negate();
}
/* Before we enter the world of square-roots and divides,
check if we're trying to join an upright right angle
(common case for stroking rectangles). If so, special case
that (for speed an accuracy).
Note: we only need to check one normal if dot==0
*/
if (0 == dotProd && invMiterLimit <= kOneOverSqrt2)
{
mid.set(SkScalarMul(before.fX + after.fX, radius),
SkScalarMul(before.fY + after.fY, radius));
goto DO_MITER;
}
/* midLength = radius / sinHalfAngle
if (midLength > miterLimit * radius) abort
if (radius / sinHalf > miterLimit * radius) abort
if (1 / sinHalf > miterLimit) abort
if (1 / miterLimit > sinHalf) abort
My dotProd is opposite sign, since it is built from normals and not tangents
hence 1 + dot instead of 1 - dot in the formula
*/
sinHalfAngle = SkScalarSqrt(SkScalarHalf(SK_Scalar1 + dotProd));
if (sinHalfAngle < invMiterLimit)
{
currIsLine = false;
goto DO_BLUNT;
}
// choose the most accurate way to form the initial mid-vector
if (angleType == kSharp_AngleType)
{
mid.set(after.fY - before.fY, before.fX - after.fX);
if (ccw)
mid.negate();
}
else
mid.set(before.fX + after.fX, before.fY + after.fY);
mid.setLength(SkScalarDiv(radius, sinHalfAngle));
DO_MITER:
if (prevIsLine)
outer->setLastPt(pivot.fX + mid.fX, pivot.fY + mid.fY);
else
outer->lineTo(pivot.fX + mid.fX, pivot.fY + mid.fY);
DO_BLUNT:
after.scale(radius);
if (!currIsLine)
outer->lineTo(pivot.fX + after.fX, pivot.fY + after.fY);
HandleInnerJoin(inner, pivot, after);
}