2 files changed, 111 insertions, 1 deletions

diff --git a/src/core/SkBitmapProcState.cpp b/src/core/SkBitmapProcState.cpp
index 7dc9324770..8a677c05be 100644
--- a/src/core/SkBitmapProcState.cpp
+++ b/src/core/SkBitmapProcState.cpp
@@ -284,6 +284,26 @@ SkASSERT(state.fAlphaScale < 256)
 #define POSTAMBLE(state)        state.fBitmap->getColorTable()->unlock16BitCache()
 #include "SkBitmapProcState_sample.h"
 
+///////////////////////////////////////////////////////////////////////////////
+
+#undef FILTER_PROC
+#define FILTER_PROC(x, y, a, b, c, d)   Filter_565_Expanded(x, y, a, b, c, d)
+
+#define TILEX_PROCF(fx, max)    SkClampMax((fx) >> 16, max)
+#define TILEY_PROCF(fy, max)    SkClampMax((fy) >> 16, max)
+#define TILEX_LOW_BITS(fx, max) (((fx) >> 12) & 0xF)
+#define TILEY_LOW_BITS(fy, max) (((fy) >> 12) & 0xF)
+
+#define MAKENAME(suffix)        Clamp_S16_D16 ## suffix
+#define SRCTYPE                 uint16_t
+#define DSTTYPE                 uint16_t
+#define CHECKSTATE(state)       SkASSERT(state.fBitmap->config() == SkBitmap::kRGB_565_Config)
+#define SRC_TO_FILTER(src)      src
+#define FILTER_TO_DST(c)        SkCompact_rgb_16((c) >> 5)
+#include "SkBitmapProcState_shaderproc.h"
+
+///////////////////////////////////////////////////////////////////////////////
+
 static bool valid_for_filtering(unsigned dimension) {
     // for filtering, width and height must fit in 14bits, since we use steal
     // 2 bits from each to store our 4bit subpixel data
@@ -295,14 +315,17 @@ bool SkBitmapProcState::chooseProcs(const SkMatrix& inv, const SkPaint& paint) {
         return false;
     }
     const SkMatrix* m;
-    
+    bool clamp_clamp;
+
     if (SkShader::kClamp_TileMode == fTileModeX &&
             SkShader::kClamp_TileMode == fTileModeY) {
         m = &inv;
+        clamp_clamp = true;
     } else {
         fUnitInvMatrix = inv;
         fUnitInvMatrix.postIDiv(fOrigBitmap.width(), fOrigBitmap.height());
         m = &fUnitInvMatrix;
+        clamp_clamp = false;
     }
     
     fBitmap = &fOrigBitmap;
@@ -463,6 +486,10 @@ bool SkBitmapProcState::chooseProcs(const SkMatrix& inv, const SkPaint& paint) {
     index >>= 1;    // shift away any opaque/alpha distinction
     fSampleProc16 = gSample16[index];
 
+    // our special-case shaderprocs
+    if (clamp_clamp && (7 == (index >> 1))) {
+        fShaderProc16 = Clamp_S16_D16_filter_DX_shaderproc;
+    }
     return true;
 }
 
diff --git a/src/core/SkBitmapProcState_shaderproc.h b/src/core/SkBitmapProcState_shaderproc.h
new file mode 100644
index 0000000000..66a6627141
--- /dev/null
+++ b/src/core/SkBitmapProcState_shaderproc.h
@@ -0,0 +1,83 @@
+#define SCALE_FILTER_NAME       MAKENAME(_filter_DX_shaderproc)
+
+#ifndef PREAMBLE
+    #define PREAMBLE(state)
+    #define PREAMBLE_PARAM_X
+    #define PREAMBLE_PARAM_Y
+    #define PREAMBLE_ARG_X
+    #define PREAMBLE_ARG_Y
+#endif
+
+
+static void SCALE_FILTER_NAME(const SkBitmapProcState& s, int x, int y,
+                              DSTTYPE* SK_RESTRICT colors, int count) {
+    SkASSERT((s.fInvType & ~(SkMatrix::kTranslate_Mask |
+                             SkMatrix::kScale_Mask)) == 0);
+    SkASSERT(s.fInvKy == 0);
+    SkASSERT(count > 0 && colors != NULL);
+    SkASSERT(s.fDoFilter);
+    SkDEBUGCODE(CHECKSTATE(s);)
+    
+    PREAMBLE(s);
+    
+    const unsigned maxX = s.fBitmap->width() - 1;
+    const SkFixed oneX = s.fFilterOneX;
+    const SkFixed dx = s.fInvSx;
+    SkFixed fx;
+    const SRCTYPE* SK_RESTRICT row0;
+    const SRCTYPE* SK_RESTRICT row1;
+    unsigned subY;
+
+    {
+        SkPoint pt;
+        s.fInvProc(*s.fInvMatrix, SkIntToScalar(x) + SK_ScalarHalf,
+                   SkIntToScalar(y) + SK_ScalarHalf, &pt);
+        SkFixed fy = SkScalarToFixed(pt.fY) - (s.fFilterOneY >> 1);
+        const unsigned maxY = s.fBitmap->height() - 1;
+        // compute our two Y values up front
+        subY = TILEY_LOW_BITS(fy, maxY);
+        int y0 = TILEY_PROCF(fy, maxY);
+        int y1 = TILEY_PROCF((fy + s.fFilterOneY), maxY);
+
+        const char* SK_RESTRICT srcAddr = (const char*)s.fBitmap->getPixels();
+        unsigned rb = s.fBitmap->rowBytes();
+        row0 = (const SRCTYPE*)(srcAddr + y0 * rb);
+        row1 = (const SRCTYPE*)(srcAddr + y1 * rb);
+        // now initialize fx
+        fx = SkScalarToFixed(pt.fX) - (oneX >> 1);
+    }
+    
+    do {
+        unsigned subX = TILEX_LOW_BITS(fx, maxX);
+        unsigned x0 = TILEX_PROCF(fx, maxX);
+        unsigned x1 = TILEX_PROCF((fx + oneX), maxX);
+
+        uint32_t c = FILTER_PROC(subX, subY,
+                                 SRC_TO_FILTER(row0[x0]),
+                                 SRC_TO_FILTER(row0[x1]),
+                                 SRC_TO_FILTER(row1[x0]),
+                                 SRC_TO_FILTER(row1[x1]));
+        *colors++ = FILTER_TO_DST(c);
+        
+        fx += dx;
+    } while (--count != 0);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+#undef MAKENAME
+#undef TILEX_PROCF
+#undef TILEY_PROCF
+#undef TILEX_LOW_BITS
+#undef TILEY_LOW_BITS
+#ifdef CHECK_FOR_DECAL
+    #undef CHECK_FOR_DECAL
+#endif
+
+#undef SCALE_FILTER_NAME
+
+#undef PREAMBLE
+#undef PREAMBLE_PARAM_X
+#undef PREAMBLE_PARAM_Y
+#undef PREAMBLE_ARG_X
+#undef PREAMBLE_ARG_Y