michael@0: 
michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: #include "SkBoundaryPatch.h"
michael@0: 
michael@0: SkBoundaryPatch::SkBoundaryPatch() : fBoundary(NULL) {}
michael@0: 
michael@0: SkBoundaryPatch::~SkBoundaryPatch() {
michael@0:     SkSafeUnref(fBoundary);
michael@0: }
michael@0: 
michael@0: SkBoundary* SkBoundaryPatch::setBoundary(SkBoundary* b) {
michael@0:     SkRefCnt_SafeAssign(fBoundary, b);
michael@0:     return b;
michael@0: }
michael@0: 
michael@0: static SkPoint SkMakePoint(SkScalar x, SkScalar y) {
michael@0:     SkPoint pt;
michael@0:     pt.set(x, y);
michael@0:     return pt;
michael@0: }
michael@0: 
michael@0: static SkPoint SkPointInterp(const SkPoint& a, const SkPoint& b, SkScalar t) {
michael@0:     return SkMakePoint(SkScalarInterp(a.fX, b.fX, t),
michael@0:                        SkScalarInterp(a.fY, b.fY, t));
michael@0: }
michael@0: 
michael@0: SkPoint SkBoundaryPatch::eval(SkScalar unitU, SkScalar unitV) {
michael@0:     SkBoundary* b = fBoundary;
michael@0:     SkPoint u = SkPointInterp(b->eval(SkBoundary::kLeft, SK_Scalar1 - unitV),
michael@0:                               b->eval(SkBoundary::kRight, unitV),
michael@0:                               unitU);
michael@0:     SkPoint v = SkPointInterp(b->eval(SkBoundary::kTop, unitU),
michael@0:                               b->eval(SkBoundary::kBottom, SK_Scalar1 - unitU),
michael@0:                               unitV);
michael@0:     return SkMakePoint(SkScalarAve(u.fX, v.fX),
michael@0:                        SkScalarAve(u.fY, v.fY));
michael@0: }
michael@0: 
michael@0: bool SkBoundaryPatch::evalPatch(SkPoint verts[], int rows, int cols) {
michael@0:     if (rows < 2 || cols < 2) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     const SkScalar invR = SkScalarInvert(SkIntToScalar(rows - 1));
michael@0:     const SkScalar invC = SkScalarInvert(SkIntToScalar(cols - 1));
michael@0: 
michael@0:     for (int y = 0; y < cols; y++) {
michael@0:         SkScalar yy = y * invC;
michael@0:         for (int x = 0; x < rows; x++) {
michael@0:             *verts++ = this->eval(x * invR, yy);
michael@0:         }
michael@0:     }
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: #include "SkGeometry.h"
michael@0: 
michael@0: SkPoint SkLineBoundary::eval(Edge e, SkScalar t) {
michael@0:     SkASSERT((unsigned)e < 4);
michael@0:     return SkPointInterp(fPts[e], fPts[(e + 1) & 3], t);
michael@0: }
michael@0: 
michael@0: SkPoint SkCubicBoundary::eval(Edge e, SkScalar t) {
michael@0:     SkASSERT((unsigned)e < 4);
michael@0: 
michael@0:     // ensure our 4th cubic wraps to the start of the first
michael@0:     fPts[12] = fPts[0];
michael@0: 
michael@0:     SkPoint loc;
michael@0:     SkEvalCubicAt(&fPts[e * 3], t, &loc, NULL, NULL);
michael@0:     return loc;
michael@0: }