Add drawBitmapLattice() API

src/core/SkNinePatchIter.cpp

-/*
- * Copyright 2015 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "SkNinePatchIter.h"
-#include "SkRect.h"
-
-bool SkNinePatchIter::Valid(int width, int height, const SkIRect& center) {
-    return !center.isEmpty() && SkIRect::MakeWH(width, height).contains(center);
-}
-
-SkNinePatchIter::SkNinePatchIter(int w, int h, const SkIRect& c, const SkRect& dst) {
-    SkASSERT(SkIRect::MakeWH(w, h).contains(c));
-
-    fSrcX[0] = 0;
-    fSrcX[1] = SkIntToScalar(c.fLeft);
-    fSrcX[2] = SkIntToScalar(c.fRight);
-    fSrcX[3] = SkIntToScalar(w);
-
-    fSrcY[0] = 0;
-    fSrcY[1] = SkIntToScalar(c.fTop);
-    fSrcY[2] = SkIntToScalar(c.fBottom);
-    fSrcY[3] = SkIntToScalar(h);
-
-    fDstX[0] = dst.fLeft;
-    fDstX[1] = dst.fLeft + SkIntToScalar(c.fLeft);
-    fDstX[2] = dst.fRight - SkIntToScalar(w - c.fRight);
-    fDstX[3] = dst.fRight;
-
-    fDstY[0] = dst.fTop;
-    fDstY[1] = dst.fTop + SkIntToScalar(c.fTop);
-    fDstY[2] = dst.fBottom - SkIntToScalar(h - c.fBottom);
-    fDstY[3] = dst.fBottom;
-
-    if (fDstX[1] > fDstX[2]) {
-        fDstX[1] = fDstX[0] + (fDstX[3] - fDstX[0]) * c.fLeft / (w - c.width());
-        fDstX[2] = fDstX[1];
-    }
-
-    if (fDstY[1] > fDstY[2]) {
-        fDstY[1] = fDstY[0] + (fDstY[3] - fDstY[0]) * c.fTop / (h - c.height());
-        fDstY[2] = fDstY[1];
-    }
-
-    fCurrX = fCurrY = 0;
-    fDone = false;
-}
-
-bool SkNinePatchIter::next(SkRect* src, SkRect* dst) {
-    if (fDone) {
-        return false;
-    }
-
-    const int x = fCurrX;
-    const int y = fCurrY;
-    SkASSERT(x >= 0 && x < 3);
-    SkASSERT(y >= 0 && y < 3);
-
-    src->set(fSrcX[x], fSrcY[y], fSrcX[x + 1], fSrcY[y + 1]);
-    dst->set(fDstX[x], fDstY[y], fDstX[x + 1], fDstY[y + 1]);
-    if (3 == ++fCurrX) {
-        fCurrX = 0;
-        fCurrY += 1;
-        if (fCurrY >= 3) {
-            fDone = true;
-        }
-    }
-    return true;
-}