Add a src rect to drawImageLattice() API

This will allow us to draw ninepatches directly from an asset
texture without having to upload them individually.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2382893002

Review-Url: https://codereview.chromium.org/2382893002

9 files changed, 81 insertions, 46 deletions

diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index 6a0d5e6da6..7597c7a07a 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -1999,8 +1999,16 @@ void SkCanvas::drawImageLattice(const SkImage* image, const Lattice& lattice, co
     if (dst.isEmpty()) {
         return;
     }
-    if (SkLatticeIter::Valid(image->width(), image->height(), lattice)) {
-        this->onDrawImageLattice(image, lattice, dst, paint);
+
+    SkIRect bounds;
+    Lattice latticePlusBounds = lattice;
+    if (!latticePlusBounds.fBounds) {
+        bounds = SkIRect::MakeWH(image->width(), image->height());
+        latticePlusBounds.fBounds = &bounds;
+    }
+
+    if (SkLatticeIter::Valid(image->width(), image->height(), latticePlusBounds)) {
+        this->onDrawImageLattice(image, latticePlusBounds, dst, paint);
     } else {
         this->drawImageRect(image, dst, paint);
     }
@@ -2049,8 +2057,16 @@ void SkCanvas::drawBitmapLattice(const SkBitmap& bitmap, const Lattice& lattice,
     if (bitmap.drawsNothing() || dst.isEmpty()) {
         return;
     }
-    if (SkLatticeIter::Valid(bitmap.width(), bitmap.height(), lattice)) {
-        this->onDrawBitmapLattice(bitmap, lattice, dst, paint);
+
+    SkIRect bounds;
+    Lattice latticePlusBounds = lattice;
+    if (!latticePlusBounds.fBounds) {
+        bounds = SkIRect::MakeWH(bitmap.width(), bitmap.height());
+        latticePlusBounds.fBounds = &bounds;
+    }
+
+    if (SkLatticeIter::Valid(bitmap.width(), bitmap.height(), latticePlusBounds)) {
+        this->onDrawBitmapLattice(bitmap, latticePlusBounds, dst, paint);
     } else {
         this->drawBitmapRect(bitmap, dst, paint);
     }
diff --git a/src/core/SkDevice.cpp b/src/core/SkDevice.cpp
index 8a9fa96926..70eabab736 100644
--- a/src/core/SkDevice.cpp
+++ b/src/core/SkDevice.cpp
@@ -219,7 +219,7 @@ void SkBaseDevice::drawBitmapNine(const SkDraw& draw, const SkBitmap& bitmap, co
 void SkBaseDevice::drawImageLattice(const SkDraw& draw, const SkImage* image,
                                     const SkCanvas::Lattice& lattice, const SkRect& dst,
                                     const SkPaint& paint) {
-    SkLatticeIter iter(image->width(), image->height(), lattice, dst);
+    SkLatticeIter iter(lattice, dst);
 
     SkRect srcR, dstR;
     while (iter.next(&srcR, &dstR)) {
@@ -230,7 +230,7 @@ void SkBaseDevice::drawImageLattice(const SkDraw& draw, const SkImage* image,
 void SkBaseDevice::drawBitmapLattice(const SkDraw& draw, const SkBitmap& bitmap,
                                      const SkCanvas::Lattice& lattice, const SkRect& dst,
                                      const SkPaint& paint) {
-    SkLatticeIter iter(bitmap.width(), bitmap.height(), lattice, dst);
+    SkLatticeIter iter(lattice, dst);
 
     SkRect srcR, dstR;
     while (iter.next(&srcR, &dstR)) {
diff --git a/src/core/SkLatticeIter.cpp b/src/core/SkLatticeIter.cpp
index 38ef2828bd..4fe9352d0a 100644
--- a/src/core/SkLatticeIter.cpp
+++ b/src/core/SkLatticeIter.cpp
@@ -11,10 +11,10 @@
 /**
  *  Divs must be in increasing order with no duplicates.
  */
-static bool valid_divs(const int* divs, int count, int len) {
-    int prev = -1;
+static bool valid_divs(const int* divs, int count, int start, int end) {
+    int prev = start - 1;
     for (int i = 0; i < count; i++) {
-        if (prev >= divs[i] || divs[i] >= len) {
+        if (prev >= divs[i] || divs[i] >= end) {
             return false;
         }
     }
@@ -23,29 +23,38 @@ static bool valid_divs(const int* divs, int count, int len) {
 }
 
 bool SkLatticeIter::Valid(int width, int height, const SkCanvas::Lattice& lattice) {
-    bool zeroXDivs = lattice.fXCount <= 0 || (1 == lattice.fXCount && 0 == lattice.fXDivs[0]);
-    bool zeroYDivs = lattice.fYCount <= 0 || (1 == lattice.fYCount && 0 == lattice.fYDivs[0]);
+    SkIRect totalBounds = SkIRect::MakeWH(width, height);
+    SkASSERT(lattice.fBounds);
+    const SkIRect latticeBounds = *lattice.fBounds;
+    if (!totalBounds.contains(latticeBounds)) {
+        return false;
+    }
+
+    bool zeroXDivs = lattice.fXCount <= 0 || (1 == lattice.fXCount &&
+                                              latticeBounds.fLeft == lattice.fXDivs[0]);
+    bool zeroYDivs = lattice.fYCount <= 0 || (1 == lattice.fYCount &&
+                                              latticeBounds.fTop == lattice.fYDivs[0]);
     if (zeroXDivs && zeroYDivs) {
         return false;
     }
 
-    return valid_divs(lattice.fXDivs, lattice.fXCount, width) &&
-           valid_divs(lattice.fYDivs, lattice.fYCount, height);
+    return valid_divs(lattice.fXDivs, lattice.fXCount, latticeBounds.fLeft, latticeBounds.fRight)
+        && valid_divs(lattice.fYDivs, lattice.fYCount, latticeBounds.fTop, latticeBounds.fBottom);
 }
 
 /**
  *  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) {
+                                 int start, int end) {
     if (0 == numDivs) {
-        return firstIsScalable ? length : 0;
+        return firstIsScalable ? end - start : 0;
     }
 
     int i;
     int count;
     if (firstIsScalable) {
-        count = divs[0];
+        count = divs[0] - start;
         i = 1;
     } else {
         count = 0;
@@ -56,7 +65,7 @@ static int count_scalable_pixels(const int32_t* divs, int numDivs, bool firstIsS
         // 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;
+        int right = (i + 1 < numDivs) ? divs[i + 1] : end;
         count += right - left;
     }
 
@@ -67,10 +76,10 @@ static int count_scalable_pixels(const int32_t* divs, int numDivs, bool firstIsS
  *  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) {
+                       int srcScalable, float srcStart, float srcEnd, float dstStart, float dstEnd,
+                       bool isScalable) {
 
-    float dstLen = dstStop - dstStart;
-    int srcLen = srcFixed + srcScalable;
+    float dstLen = dstEnd - dstStart;
     float scale;
     if (srcFixed <= dstLen) {
         // This is the "normal" case, where we scale the "scalable" patches and leave
@@ -81,7 +90,7 @@ static void set_points(float* dst, float* src, const int* divs, int divCount, in
         scale = dstLen / ((float) srcFixed);
     }
 
-    src[0] = 0.0f;
+    src[0] = srcStart;
     dst[0] = dstStart;
     for (int i = 0; i < divCount; i++) {
         src[i + 1] = (float) (divs[i]);
@@ -98,17 +107,17 @@ static void set_points(float* dst, float* src, const int* divs, int divCount, in
         isScalable = !isScalable;
     }
 
-    src[divCount + 1] = (float) srcLen;
-    dst[divCount + 1] = dstStop;
+    src[divCount + 1] = srcEnd;
+    dst[divCount + 1] = dstEnd;
 }
 
-SkLatticeIter::SkLatticeIter(int srcWidth, int srcHeight, const SkCanvas::Lattice& lattice,
-                             const SkRect& dst)
-{
+SkLatticeIter::SkLatticeIter(const SkCanvas::Lattice& lattice, const SkRect& dst) {
     const int* xDivs = lattice.fXDivs;
     const int origXCount = lattice.fXCount;
     const int* yDivs = lattice.fYDivs;
     const int origYCount = lattice.fYCount;
+    SkASSERT(lattice.fBounds);
+    const SkIRect src = *lattice.fBounds;
 
     // 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
@@ -121,36 +130,36 @@ SkLatticeIter::SkLatticeIter(int srcWidth, int srcHeight, const SkCanvas::Lattic
     // patches will be "fixed" or "scalable" in the y-direction.
     int xCount = origXCount;
     int yCount = origYCount;
-    bool xIsScalable = (xCount > 0 && 0 == xDivs[0]);
+    bool xIsScalable = (xCount > 0 && src.fLeft == 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.
+        // xDiv.  It is always implied that we start at the edge of the bounds.
         xDivs++;
         xCount--;
     }
-    bool yIsScalable = (yCount > 0 && 0 == yDivs[0]);
+    bool yIsScalable = (yCount > 0 && src.fTop == 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.
+        // yDiv.  It is always implied that we start at the edge of the bounds.
         yDivs++;
         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;
+    int xCountScalable = count_scalable_pixels(xDivs, xCount, xIsScalable, src.fLeft, src.fRight);
+    int xCountFixed = src.width() - xCountScalable;
+    int yCountScalable = count_scalable_pixels(yDivs, yCount, yIsScalable, src.fTop, src.fBottom);
+    int yCountFixed = src.height() - yCountScalable;
 
     fSrcX.reset(xCount + 2);
     fDstX.reset(xCount + 2);
     set_points(fDstX.begin(), fSrcX.begin(), xDivs, xCount, xCountFixed, xCountScalable,
-               dst.fLeft, dst.fRight, xIsScalable);
+               src.fLeft, src.fRight, 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);
+               src.fTop, src.fBottom, dst.fTop, dst.fBottom, yIsScalable);
 
     fCurrX = fCurrY = 0;
     fNumRectsInLattice = (xCount + 1) * (yCount + 1);
diff --git a/src/core/SkLatticeIter.h b/src/core/SkLatticeIter.h
index deb2fe95eb..f3d37e6688 100644
--- a/src/core/SkLatticeIter.h
+++ b/src/core/SkLatticeIter.h
@@ -23,8 +23,7 @@ public:
 
     static bool Valid(int imageWidth, int imageHeight, const SkCanvas::Lattice& lattice);
 
-    SkLatticeIter(int imageWidth, int imageHeight, const SkCanvas::Lattice& lattice,
-                  const SkRect& dst);
+    SkLatticeIter(const SkCanvas::Lattice& lattice, const SkRect& dst);
 
     static bool Valid(int imageWidth, int imageHeight, const SkIRect& center);
 
diff --git a/src/core/SkLiteDL.cpp b/src/core/SkLiteDL.cpp
index 8e64ae0a7d..701e9bd38f 100644
--- a/src/core/SkLiteDL.cpp
+++ b/src/core/SkLiteDL.cpp
@@ -353,12 +353,13 @@ namespace {
     struct DrawImageLattice final : Op {
         static const auto kType = Type::DrawImageLattice;
         DrawImageLattice(sk_sp<const SkImage>&& image, int xs, int ys, int fs,
-                         const SkRect& dst, const SkPaint* paint)
-            : image(std::move(image)), xs(xs), ys(ys), fs(fs), dst(dst) {
+                         const SkIRect& src, const SkRect& dst, const SkPaint* paint)
+            : image(std::move(image)), xs(xs), ys(ys), fs(fs), src(src), dst(dst) {
             if (paint) { this->paint = *paint; }
         }
         sk_sp<const SkImage> image;
         int                  xs, ys, fs;
+        SkIRect              src;
         SkRect               dst;
         SkPaint              paint;
         void draw(SkCanvas* c, const SkMatrix&) {
@@ -366,7 +367,7 @@ namespace {
                  ydivs = pod<int>(this, xs*sizeof(int));
             auto flags = (0 == fs) ? nullptr :
                                      pod<SkCanvas::Lattice::Flags>(this, (xs+ys)*sizeof(int));
-            c->drawImageLattice(image.get(), {xdivs, ydivs, flags, xs, ys}, dst, &paint);
+            c->drawImageLattice(image.get(), {xdivs, ydivs, flags, xs, ys, &src}, dst, &paint);
         }
     };
 
@@ -669,8 +670,9 @@ void SkLiteDL::drawBitmapLattice(const SkBitmap& bm, const SkCanvas::Lattice& la
     int xs = lattice.fXCount, ys = lattice.fYCount;
     int fs = lattice.fFlags ? (xs + 1) * (ys + 1) : 0;
     size_t bytes = (xs + ys) * sizeof(int) + fs * sizeof(SkCanvas::Lattice::Flags);
-    void* pod = this->push<DrawImageLattice>(bytes, SkImage::MakeFromBitmap(bm), xs, ys, fs, dst,
-                                             paint);
+    SkASSERT(lattice.fBounds);
+    void* pod = this->push<DrawImageLattice>(bytes, SkImage::MakeFromBitmap(bm), xs, ys, fs,
+                                             *lattice.fBounds, dst, paint);
     copy_v(pod, lattice.fXDivs, xs,
                 lattice.fYDivs, ys,
                 lattice.fFlags, fs);
@@ -692,7 +694,9 @@ void SkLiteDL::drawImageLattice(const SkImage* image, const SkCanvas::Lattice& l
     int xs = lattice.fXCount, ys = lattice.fYCount;
     int fs = lattice.fFlags ? (xs + 1) * (ys + 1) : 0;
     size_t bytes = (xs + ys) * sizeof(int) + fs * sizeof(SkCanvas::Lattice::Flags);
-    void* pod = this->push<DrawImageLattice>(bytes, sk_ref_sp(image), xs, ys, fs, dst, paint);
+    SkASSERT(lattice.fBounds);
+    void* pod = this->push<DrawImageLattice>(bytes, sk_ref_sp(image), xs, ys, fs, *lattice.fBounds,
+                                             dst, paint);
     copy_v(pod, lattice.fXDivs, xs,
                 lattice.fYDivs, ys,
                 lattice.fFlags, fs);
diff --git a/src/core/SkPicturePlayback.cpp b/src/core/SkPicturePlayback.cpp
index 1aa4712d4f..a246a306e6 100644
--- a/src/core/SkPicturePlayback.cpp
+++ b/src/core/SkPicturePlayback.cpp
@@ -327,6 +327,9 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
             int flagCount = reader->readInt();
             lattice.fFlags = (0 == flagCount) ? nullptr : (const SkCanvas::Lattice::Flags*)
                     reader->skip(SkAlign4(flagCount * sizeof(SkCanvas::Lattice::Flags)));
+            SkIRect src;
+            reader->readIRect(&src);
+            lattice.fBounds = &src;
             SkRect dst;
             reader->readRect(&dst);
             canvas->drawImageLattice(image, lattice, dst, paint);
diff --git a/src/core/SkPictureRecord.cpp b/src/core/SkPictureRecord.cpp
index 4cba3b067f..6325edae00 100644
--- a/src/core/SkPictureRecord.cpp
+++ b/src/core/SkPictureRecord.cpp
@@ -540,7 +540,7 @@ void SkPictureRecord::onDrawImageLattice(const SkImage* image, const Lattice& la
     // xCount + xDivs + yCount+ yDivs
     int flagCount = (nullptr == lattice.fFlags) ? 0 : (lattice.fXCount + 1) * (lattice.fYCount + 1);
     size_t latticeSize = (1 + lattice.fXCount + 1 + lattice.fYCount + 1) * kUInt32Size +
-                         SkAlign4(flagCount * sizeof(SkCanvas::Lattice::Flags));
+                         SkAlign4(flagCount * sizeof(SkCanvas::Lattice::Flags)) + sizeof(SkIRect);
 
     // op + paint index + image index + lattice + dst rect
     size_t size = 3 * kUInt32Size + latticeSize + sizeof(dst);
@@ -553,6 +553,8 @@ void SkPictureRecord::onDrawImageLattice(const SkImage* image, const Lattice& la
     fWriter.writePad(lattice.fYDivs, lattice.fYCount * kUInt32Size);
     this->addInt(flagCount);
     fWriter.writePad(lattice.fFlags, flagCount * sizeof(SkCanvas::Lattice::Flags));
+    SkASSERT(lattice.fBounds);
+    this->addIRect(*lattice.fBounds);
     this->addRect(dst);
     this->validate(initialOffset, size);
 }
diff --git a/src/core/SkRecordDraw.cpp b/src/core/SkRecordDraw.cpp
index 2952591319..ca9c1b6f78 100644
--- a/src/core/SkRecordDraw.cpp
+++ b/src/core/SkRecordDraw.cpp
@@ -107,6 +107,7 @@ template <> void Draw::draw(const DrawImageLattice& r) {
     lattice.fYCount = r.yCount;
     lattice.fYDivs = r.yDivs;
     lattice.fFlags = (0 == r.flagCount) ? nullptr : r.flags;
+    lattice.fBounds = &r.src;
     fCanvas->drawImageLattice(r.image.get(), lattice, r.dst, r.paint);
 }
 
diff --git a/src/core/SkRecorder.cpp b/src/core/SkRecorder.cpp
index 0c236716bc..08c73700d8 100644
--- a/src/core/SkRecorder.cpp
+++ b/src/core/SkRecorder.cpp
@@ -239,10 +239,11 @@ void SkRecorder::onDrawImageNine(const SkImage* image, const SkIRect& center,
 void SkRecorder::onDrawImageLattice(const SkImage* image, const Lattice& lattice, const SkRect& dst,
                                     const SkPaint* paint) {
     int flagCount = lattice.fFlags ? (lattice.fXCount + 1) * (lattice.fYCount + 1) : 0;
+    SkASSERT(lattice.fBounds);
     APPEND(DrawImageLattice, this->copy(paint), sk_ref_sp(image),
            lattice.fXCount, this->copy(lattice.fXDivs, lattice.fXCount),
            lattice.fYCount, this->copy(lattice.fYDivs, lattice.fYCount),
-           flagCount, this->copy(lattice.fFlags, flagCount), dst);
+           flagCount, this->copy(lattice.fFlags, flagCount), *lattice.fBounds, dst);
 }
 
 void SkRecorder::onDrawText(const void* text, size_t byteLength,