Revert of Redo Tiling

src/core/SkLinearBitmapPipeline_core.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkLinearBitmapPipeline_core_DEFINED
 #define SkLinearBitmapPipeline_core_DEFINED
 
@@ skipping 160 matching lines @@
 
     while (count >= 4) {
         stage->pointList4(xs, ys);
         xs = xs + fourDx;
         count -= 4;
     }
     if (count > 0) {
         stage->pointListFew(count, xs, ys);
     }
 }
-
-inline Sk4f check_pixel(Sk4f& pixel) {
-    SkASSERTF(0.0f <= pixel[0] && pixel[0] <= 1.0f, "pixel[0]: %f", pixel[0]);
-    SkASSERTF(0.0f <= pixel[1] && pixel[1] <= 1.0f, "pixel[1]: %f", pixel[1]);
-    SkASSERTF(0.0f <= pixel[2] && pixel[2] <= 1.0f, "pixel[2]: %f", pixel[2]);
-    SkASSERTF(0.0f <= pixel[3] && pixel[3] <= 1.0f, "pixel[3]: %f", pixel[3]);
-    return pixel;
-}
-
 }  // namespace
 
 class SkLinearBitmapPipeline::PointProcessorInterface {
 public:
     virtual ~PointProcessorInterface() { }
     // Take the first n (where 0 < n && n < 4) items from xs and ys and sample those points. For
     // nearest neighbor, that means just taking the floor xs and ys. For bilerp, this means
     // to expand the bilerp filter around the point and sample using that filter.
     virtual void SK_VECTORCALL pointListFew(int n, Sk4s xs, Sk4s ys) = 0;
     // Same as pointListFew, but n = 4.
     virtual void SK_VECTORCALL pointList4(Sk4s xs, Sk4s ys) = 0;
     // A span is a compact form of sample points that are obtained by mapping points from
     // destination space to source space. This is used for horizontal lines only, and is mainly
     // used to take advantage of memory coherence for horizontal spans.
     virtual void pointSpan(Span span) = 0;
 };
 
 class SkLinearBitmapPipeline::SampleProcessorInterface
     : public SkLinearBitmapPipeline::PointProcessorInterface {
 public:
     // Used for nearest neighbor when scale factor is 1.0. The span can just be repeated with no
     // edge pixel alignment problems. This is for handling a very common case.
     virtual void repeatSpan(Span span, int32_t repeatCount) = 0;
+
+    // The x's and y's are setup in the following order:
+    // +--------+--------+
+    // |        |        |
+    // |  px00  |  px10  |
+    // |    0   |    1   |
+    // +--------+--------+
+    // |        |        |
+    // |  px01  |  px11  |
+    // |    2   |    3   |
+    // +--------+--------+
+    // These pixels coordinates are arranged in the following order in xs and ys:
+    // px00  px10  px01  px11
+    virtual void SK_VECTORCALL bilerpEdge(Sk4s xs, Sk4s ys) = 0;
+
+    // A span represents sample points that have been mapped from destination space to source
+    // space. Each sample point is then expanded to the four bilerp points by add +/- 0.5. The
+    // resulting Y values my be off the tile. When y +/- 0.5 are more than 1 apart because of
+    // tiling, the second Y is used to denote the retiled Y value.
+    virtual void bilerpSpan(Span span, SkScalar y) = 0;
 };
 
 class SkLinearBitmapPipeline::DestinationInterface {
 public:
     virtual ~DestinationInterface() { }
     // Count is normally not needed, but in these early stages of development it is useful to
     // check bounds.
     // TODO(herb): 4/6/2016 - remove count when code is stable.
     virtual void setDestination(void* dst, int count) = 0;
 };
 
 class SkLinearBitmapPipeline::BlendProcessorInterface
     : public SkLinearBitmapPipeline::DestinationInterface {
 public:
     virtual void SK_VECTORCALL blendPixel(Sk4f pixel0) = 0;
     virtual void SK_VECTORCALL blend4Pixels(Sk4f p0, Sk4f p1, Sk4f p2, Sk4f p3) = 0;
 };
 
 class SkLinearBitmapPipeline::PixelAccessorInterface {
 public:
     virtual ~PixelAccessorInterface() { }
     virtual void SK_VECTORCALL getFewPixels(
-        int n, Sk4i xs, Sk4i ys, Sk4f* px0, Sk4f* px1, Sk4f* px2) const = 0;
+        int n, Sk4s xs, Sk4s ys, Sk4f* px0, Sk4f* px1, Sk4f* px2) const = 0;
 
     virtual void SK_VECTORCALL get4Pixels(
-        Sk4i xs, Sk4i ys, Sk4f* px0, Sk4f* px1, Sk4f* px2, Sk4f* px3) const = 0;
+        Sk4s xs, Sk4s ys, Sk4f* px0, Sk4f* px1, Sk4f* px2, Sk4f* px3) const = 0;
 
     virtual void get4Pixels(
         const void* src, int index, Sk4f* px0, Sk4f* px1, Sk4f* px2, Sk4f* px3) const = 0;
 
     virtual Sk4f getPixelFromRow(const void* row, int index) const = 0;
 
     virtual Sk4f getPixelAt(int index) const = 0;
 
     virtual const void* row(int y) const = 0;
 };
 
 #endif // SkLinearBitmapPipeline_core_DEFINED