int SkEdge::setLine(const SkPoint& p0, const SkPoint& p1, const SkIRect* clip,
int shift) {
SkFDot6 x0, y0, x1, y1;
{
#ifdef SK_RASTERIZE_EVEN_ROUNDING
x0 = SkScalarRoundToFDot6(p0.fX, shift);
y0 = SkScalarRoundToFDot6(p0.fY, shift);
x1 = SkScalarRoundToFDot6(p1.fX, shift);
y1 = SkScalarRoundToFDot6(p1.fY, shift);
#else
float scale = float(1 << (shift + 6));
x0 = int(p0.fX * scale);
y0 = int(p0.fY * scale);
x1 = int(p1.fX * scale);
y1 = int(p1.fY * scale);
#endif
}
int winding = 1;
if (y0 > y1) {
SkTSwap(x0, x1);
SkTSwap(y0, y1);
winding = -1;
}
int top = SkFDot6Round(y0);
int bot = SkFDot6Round(y1);
// are we a zero-height line?
if (top == bot) {
return 0;
}
// are we completely above or below the clip?
if (clip && (top >= clip->fBottom || bot <= clip->fTop)) {
return 0;
}
SkFixed slope = SkFDot6Div(x1 - x0, y1 - y0);
const SkFDot6 dy = SkEdge_Compute_DY(top, y0);
fX = SkFDot6ToFixed(x0 + SkFixedMul(slope, dy)); // + SK_Fixed1/2
fDX = slope;
fFirstY = top;
fLastY = bot - 1;
fCurveCount = 0;
fWinding = SkToS8(winding);
fCurveShift = 0;
if (clip) {
this->chopLineWithClip(*clip);
}
return 1;
}
int SkEdge::setLine(const SkPoint& p0, const SkPoint& p1, const SkIRect* clip,
int shift) {
SkFDot6 x0, y0, x1, y1;
{
#ifdef SK_SCALAR_IS_FLOAT
float scale = float(1 << (shift + 6));
x0 = int(p0.fX * scale);
y0 = int(p0.fY * scale);
x1 = int(p1.fX * scale);
y1 = int(p1.fY * scale);
#else
shift = 10 - shift;
x0 = p0.fX >> shift;
y0 = p0.fY >> shift;
x1 = p1.fX >> shift;
y1 = p1.fY >> shift;
#endif
}
int winding = 1;
if (y0 > y1) {
SkTSwap(x0, x1);
SkTSwap(y0, y1);
winding = -1;
}
int top = SkFDot6Round(y0);
int bot = SkFDot6Round(y1);
// are we a zero-height line?
if (top == bot) {
return 0;
}
// are we completely above or below the clip?
if (NULL != clip && (top >= clip->fBottom || bot <= clip->fTop)) {
return 0;
}
SkFixed slope = SkFDot6Div(x1 - x0, y1 - y0);
fX = SkFDot6ToFixed(x0 + SkFixedMul(slope, (32 - y0) & 63)); // + SK_Fixed1/2
fDX = slope;
fFirstY = top;
fLastY = bot - 1;
fCurveCount = 0;
fWinding = SkToS8(winding);
fCurveShift = 0;
if (clip) {
this->chopLineWithClip(*clip);
}
return 1;
}