| /* |
| * 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 "SkLatticeIter.h" |
| #include "SkRect.h" |
| |
| /** |
| * Divs must be in increasing order with no duplicates. |
| */ |
| static bool valid_divs(const int* divs, int count, int len) { |
| if (count <= 0) { |
| return false; |
| } |
| |
| int prev = -1; |
| for (int i = 0; i < count; i++) { |
| if (prev >= divs[i] || divs[i] > len) { |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool SkLatticeIter::Valid(int width, int height, const SkCanvas::Lattice& lattice) { |
| return valid_divs(lattice.fXDivs, lattice.fXCount, width) && |
| valid_divs(lattice.fYDivs, lattice.fYCount, height); |
| } |
| |
| /** |
| * Count the number of pixels that are in "scalable" patches. |
| */ |
| static int count_scalable_pixels(const int32_t* divs, int numDivs, bool firstIsScalable, |
| int length) { |
| if (0 == numDivs) { |
| return firstIsScalable ? length : 0; |
| } |
| |
| int i; |
| int count; |
| if (firstIsScalable) { |
| count = divs[0]; |
| i = 1; |
| } else { |
| count = 0; |
| i = 0; |
| } |
| |
| for (; i < numDivs; i += 2) { |
| // Alternatively, we could use |top| and |bottom| as variable names, instead of |
| // |left| and |right|. |
| int left = divs[i]; |
| int right = (i + 1 < numDivs) ? divs[i + 1] : length; |
| count += right - left; |
| } |
| |
| return count; |
| } |
| |
| /** |
| * Set points for the src and dst rects on subsequent draw calls. |
| */ |
| static void set_points(float* dst, float* src, const int* divs, int divCount, int srcFixed, |
| int srcScalable, float dstStart, float dstStop, bool isScalable) { |
| |
| float dstLen = dstStop - dstStart; |
| int srcLen = srcFixed + srcScalable; |
| float scale; |
| if (srcFixed <= dstLen) { |
| // This is the "normal" case, where we scale the "scalable" patches and leave |
| // the other patches fixed. |
| scale = (dstLen - ((float) srcFixed)) / ((float) srcScalable); |
| } else { |
| // In this case, we eliminate the "scalable" patches and scale the "fixed" patches. |
| scale = dstLen / ((float) srcFixed); |
| } |
| |
| src[0] = 0.0f; |
| dst[0] = dstStart; |
| for (int i = 0; i < divCount; i++) { |
| src[i + 1] = (float) (divs[i]); |
| float srcDelta = src[i + 1] - src[i]; |
| float dstDelta; |
| if (srcFixed <= dstLen) { |
| dstDelta = isScalable ? scale * srcDelta : srcDelta; |
| } else { |
| dstDelta = isScalable ? 0.0f : scale * srcDelta; |
| } |
| dst[i + 1] = dst[i] + dstDelta; |
| |
| // Alternate between "scalable" and "fixed" patches. |
| isScalable = !isScalable; |
| } |
| |
| src[divCount + 1] = (float) srcLen; |
| dst[divCount + 1] = dstStop; |
| } |
| |
| SkLatticeIter::SkLatticeIter(int srcWidth, int srcHeight, const SkCanvas::Lattice& lattice, |
| const SkRect& dst) |
| { |
| const int* xDivs = lattice.fXDivs; |
| int xCount = lattice.fXCount; |
| const int* yDivs = lattice.fYDivs; |
| int yCount = lattice.fYCount; |
| |
| // In the x-dimension, the first rectangle always starts at x = 0 and is "scalable". |
| // If xDiv[0] is 0, it indicates that the first rectangle is degenerate, so the |
| // first real rectangle "scalable" in the x-direction. |
| // |
| // The same interpretation applies to the y-dimension. |
| // |
| // As we move left to right across the image, alternating patches will be "fixed" or |
| // "scalable" in the x-direction. Similarly, as move top to bottom, alternating |
| // patches will be "fixed" or "scalable" in the y-direction. |
| SkASSERT(xCount > 0 && yCount > 0); |
| bool xIsScalable = (0 == xDivs[0]); |
| if (xIsScalable) { |
| // Once we've decided that the first patch is "scalable", we don't need the |
| // xDiv. It is always implied that we start at zero. |
| xDivs++; |
| xCount--; |
| } |
| bool yIsScalable = (0 == yDivs[0]); |
| if (yIsScalable) { |
| // Once we've decided that the first patch is "scalable", we don't need the |
| // yDiv. It is always implied that we start at zero. |
| yDivs++; |
| yCount--; |
| } |
| |
| // We never need the final xDiv/yDiv if it is equal to the width/height. This is implied. |
| if (xCount > 0 && srcWidth == xDivs[xCount - 1]) { |
| xCount--; |
| } |
| if (yCount > 0 && srcHeight == yDivs[yCount - 1]) { |
| yCount--; |
| } |
| |
| // Count "scalable" and "fixed" pixels in each dimension. |
| int xCountScalable = count_scalable_pixels(xDivs, xCount, xIsScalable, srcWidth); |
| int xCountFixed = srcWidth - xCountScalable; |
| int yCountScalable = count_scalable_pixels(yDivs, yCount, yIsScalable, srcHeight); |
| int yCountFixed = srcHeight - yCountScalable; |
| |
| fSrcX.reset(xCount + 2); |
| fDstX.reset(xCount + 2); |
| set_points(fDstX.begin(), fSrcX.begin(), xDivs, xCount, xCountFixed, xCountScalable, |
| dst.fLeft, dst.fRight, xIsScalable); |
| |
| fSrcY.reset(yCount + 2); |
| fDstY.reset(yCount + 2); |
| set_points(fDstY.begin(), fSrcY.begin(), yDivs, yCount, yCountFixed, yCountScalable, |
| dst.fTop, dst.fBottom, yIsScalable); |
| |
| fCurrX = fCurrY = 0; |
| fDone = false; |
| fNumRects = (xCount + 1) * (yCount + 1); |
| } |
| |
| bool SkLatticeIter::Valid(int width, int height, const SkIRect& center) { |
| return !center.isEmpty() && SkIRect::MakeWH(width, height).contains(center); |
| } |
| |
| SkLatticeIter::SkLatticeIter(int w, int h, const SkIRect& c, const SkRect& dst) { |
| SkASSERT(SkIRect::MakeWH(w, h).contains(c)); |
| |
| fSrcX.reset(4); |
| fSrcY.reset(4); |
| fDstX.reset(4); |
| fDstY.reset(4); |
| |
| 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; |
| fNumRects = 9; |
| } |
| |
| bool SkLatticeIter::next(SkRect* src, SkRect* dst) { |
| if (fDone) { |
| return false; |
| } |
| |
| const int x = fCurrX; |
| const int y = fCurrY; |
| SkASSERT(x >= 0 && x < fSrcX.count() - 1); |
| SkASSERT(y >= 0 && y < fSrcY.count() - 1); |
| |
| 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 (fSrcX.count() - 1 == ++fCurrX) { |
| fCurrX = 0; |
| fCurrY += 1; |
| if (fCurrY >= fSrcY.count() - 1) { |
| fDone = true; |
| } |
| } |
| return true; |
| } |
| |
| void SkLatticeIter::mapDstScaleTranslate(const SkMatrix& matrix) { |
| SkASSERT(matrix.isScaleTranslate()); |
| SkScalar tx = matrix.getTranslateX(); |
| SkScalar sx = matrix.getScaleX(); |
| for (int i = 0; i < fDstX.count(); i++) { |
| fDstX[i] = fDstX[i] * sx + tx; |
| } |
| |
| SkScalar ty = matrix.getTranslateY(); |
| SkScalar sy = matrix.getScaleY(); |
| for (int i = 0; i < fDstY.count(); i++) { |
| fDstY[i] = fDstY[i] * sy + ty; |
| } |
| } |