use Sk2s for EvalQuadTangent and ChopQuadAt

src/core/SkGeometry.cpp

 /*
  * 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 "SkGeometry.h"
 #include "SkMatrix.h"
+#include "Sk2x.h"
 
 /** If defined, this makes eval_quad and eval_cubic do more setup (sometimes
     involving integer multiplies by 2 or 3, but fewer calls to SkScalarMul.
     May also introduce overflow of fixed when we compute our setup.
 */
 //    #define DIRECT_EVAL_OF_POLYNOMIALS
 
 ////////////////////////////////////////////////////////////////////////
 
 static int is_not_monotonic(SkScalar a, SkScalar b, SkScalar c) {
@@ skipping 100 matching lines @@
 
     if (pt) {
         pt->set(eval_quad(&src[0].fX, t), eval_quad(&src[0].fY, t));
     }
     if (tangent) {
         tangent->set(eval_quad_derivative(&src[0].fX, t),
                      eval_quad_derivative(&src[0].fY, t));
     }
 }
 
-#include "Sk2x.h"
-
 SkPoint SkEvalQuadAt(const SkPoint src[3], SkScalar t) {
     SkASSERT(src);
     SkASSERT(t >= 0 && t <= SK_Scalar1);
 
     const Sk2f t2(t);
 
     Sk2f P0 = Sk2f::Load(&src[0].fX);
     Sk2f P1 = Sk2f::Load(&src[1].fX);
     Sk2f P2 = Sk2f::Load(&src[2].fX);
 
     Sk2f B = P1 - P0;
     Sk2f A = P2 - P1 - B;
 
     SkPoint result;
     ((A * t2 + B+B) * t2 + P0).store(&result.fX);
     return result;
 }
 
+SkVector SkEvalQuadTangentAt(const SkPoint src[3], SkScalar t) {
+    SkASSERT(src);
+    SkASSERT(t >= 0 && t <= SK_Scalar1);
+
+    Sk2f P0 = Sk2f::Load(&src[0].fX);
+    Sk2f P1 = Sk2f::Load(&src[1].fX);
+    Sk2f P2 = Sk2f::Load(&src[2].fX);
+
+    Sk2f B = P1 - P0;
+    Sk2f A = P2 - P1 - B;
+    Sk2f T = A * Sk2f(t) + B;
+
+    SkVector result;
+    (T + T).store(&result.fX);
+    return result;
+}
+
 static void interp_quad_coords(const SkScalar* src, SkScalar* dst, SkScalar t) {
     SkScalar    ab = SkScalarInterp(src[0], src[2], t);
     SkScalar    bc = SkScalarInterp(src[2], src[4], t);
 
     dst[0] = src[0];
     dst[2] = ab;
     dst[4] = SkScalarInterp(ab, bc, t);
     dst[6] = bc;
     dst[8] = src[4];
 }
 
 void SkChopQuadAt(const SkPoint src[3], SkPoint dst[5], SkScalar t) {
     SkASSERT(t > 0 && t < SK_Scalar1);
 
     interp_quad_coords(&src[0].fX, &dst[0].fX, t);
     interp_quad_coords(&src[0].fY, &dst[0].fY, t);
 }
 
+static inline Sk2s interp(const Sk2s& v0, const Sk2s& v1, const Sk2s& t) {
+    return v0 + (v1 - v0) * t;
+}
+
+void SkChopQuadAt2(const SkPoint src[3], SkPoint dst[5], SkScalar t) {
+    SkASSERT(t > 0 && t < SK_Scalar1);
+
+    Sk2s p0 = Sk2f::Load(&src[0].fX);
+    Sk2s p1 = Sk2f::Load(&src[1].fX);
+    Sk2s p2 = Sk2f::Load(&src[2].fX);
+    Sk2s tt = Sk2s(t);
+    
+    Sk2s p01 = interp(p0, p1, tt);
+    Sk2s p12 = interp(p1, p2, tt);
+
+    p0.store(&dst[0].fX);
+    p01.store(&dst[1].fX);
+    interp(p01, p12, tt).store(&dst[2].fX);
+    p12.store(&dst[3].fX);
+    p2.store(&dst[4].fX);
+}
+
 void SkChopQuadAtHalf(const SkPoint src[3], SkPoint dst[5]) {
     SkScalar x01 = SkScalarAve(src[0].fX, src[1].fX);
     SkScalar y01 = SkScalarAve(src[0].fY, src[1].fY);
     SkScalar x12 = SkScalarAve(src[1].fX, src[2].fX);
     SkScalar y12 = SkScalarAve(src[1].fY, src[2].fY);
 
     dst[0] = src[0];
     dst[1].set(x01, y01);
     dst[2].set(SkScalarAve(x01, x12), SkScalarAve(y01, y12));
     dst[3].set(x12, y12);
@@ skipping 1301 matching lines @@
         matrix.preScale(SK_Scalar1, -SK_Scalar1);
     }
     if (userMatrix) {
         matrix.postConcat(*userMatrix);
     }
     for (int i = 0; i < conicCount; ++i) {
         matrix.mapPoints(dst[i].fPts, 3);
     }
     return conicCount;
 }