ArcLengthIntegrator::ArcLengthIntegrator(const SkPoint* pts, SkSegType segType)
: fSegType(segType) {
switch (fSegType) {
case kQuad_SegType: {
float Ax = pts[0].x();
float Bx = pts[1].x();
float Cx = pts[2].x();
float Ay = pts[0].y();
float By = pts[1].y();
float Cy = pts[2].y();
// precompute coefficients for derivative
Sk8f(2*(Ax - 2*Bx + Cx)).store(&xCoeff[0]);
Sk8f(2*(Bx - Ax)).store(&xCoeff[1]);
Sk8f(2*(Ay - 2*By + Cy)).store(&yCoeff[0]);
Sk8f(2*(By - Ay)).store(&yCoeff[1]);
}
break;
case kCubic_SegType:
{
float Ax = pts[0].x();
float Bx = pts[1].x();
float Cx = pts[2].x();
float Dx = pts[3].x();
float Ay = pts[0].y();
float By = pts[1].y();
float Cy = pts[2].y();
float Dy = pts[3].y();
// precompute coefficients for derivative
Sk8f(3*(-Ax + 3*(Bx - Cx) + Dx)).store(&xCoeff[0]);
Sk8f(6*(Ax - 2*Bx + Cx)).store(&xCoeff[1]);
Sk8f(3*(-Ax + Bx)).store(&xCoeff[2]);
Sk8f(3*(-Ay + 3*(By - Cy) + Dy)).store(&yCoeff[0]);
Sk8f(6*(Ay - 2*By + Cy)).store(&yCoeff[1]);
Sk8f(3*(-Ay + By)).store(&yCoeff[2]);
}
break;
case kConic_SegType:
UNIMPLEMENTED;
break;
default:
UNIMPLEMENTED;
}
}
ArcLengthIntegrator::ArcLengthIntegrator(const SkPoint* pts, SkSegType segType)
: fSegType(segType) {
switch (fSegType) {
case kQuad_SegType: {
float Ax = pts[0].x();
float Bx = pts[1].x();
float Cx = pts[2].x();
float Ay = pts[0].y();
float By = pts[1].y();
float Cy = pts[2].y();
// precompute coefficients for derivative
xCoeff[0] = Sk8f(2.0f*(Ax - 2*Bx + Cx));
xCoeff[1] = Sk8f(2.0f*(Bx - Ax));
yCoeff[0] = Sk8f(2.0f*(Ay - 2*By + Cy));
yCoeff[1] = Sk8f(2.0f*(By - Ay));
}
break;
case kLine_SegType: {
// the length of the derivative of a line is constant
// we put in in both coeff arrays for consistency's sake
SkScalar length = (pts[1] - pts[0]).length();
xCoeff[0] = Sk8f(length);
yCoeff[0] = Sk8f(length);
}
break;
case kCubic_SegType:
{
float Ax = pts[0].x();
float Bx = pts[1].x();
float Cx = pts[2].x();
float Dx = pts[3].x();
float Ay = pts[0].y();
float By = pts[1].y();
float Cy = pts[2].y();
float Dy = pts[3].y();
// precompute coefficients for derivative
xCoeff[0] = Sk8f(3.0f*(-Ax + 3.0f*(Bx - Cx) + Dx));
xCoeff[1] = Sk8f(3.0f*(2.0f*(Ax - 2.0f*Bx + Cx)));
xCoeff[2] = Sk8f(3.0f*(-Ax + Bx));
yCoeff[0] = Sk8f(3.0f*(-Ay + 3.0f*(By - Cy) + Dy));
yCoeff[1] = Sk8f(3.0f * -Ay + By + 2.0f*(Ay - 2.0f*By + Cy));
yCoeff[2] = Sk8f(3.0f*(-Ay + By));
}
break;
case kConic_SegType:
UNIMPLEMENTED;
break;
default:
UNIMPLEMENTED;
}
}
