add a simple ascii-art debug thing for AA clips

src/core/SkAAClip.cpp

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkAAClip.h"
 #include "SkBlitter.h"
@@ skipping 201 matching lines @@
         prevOffset = yoff->fOffset;
         const uint8_t* row = head->data() + yoff->fOffset;
         size_t rowLength = compute_row_length(row, fBounds.width());
         SkASSERT(yoff->fOffset + rowLength <= head->fDataSize);
         yoff += 1;
     }
     // check the last entry;
     --yoff;
     SkASSERT(yoff->fY == lastY);
 }
+
+static void dump_one_row(const uint8_t* SK_RESTRICT row,
+                         int width, int leading_num) {
+    if (leading_num) {
+        SkDebugf( "%03d ", leading_num );
+    }
+    while (width > 0) {
+        int n = row[0];
+        int val = row[1];
+        char out = '.';
+        if (val == 0xff) {
+            out = '*';
+        } else if (val > 0) {
+            out = '+';
+        }
+        for (int i = 0 ; i < n ; i++) {
+            SkDebugf( "%c", out );
+        }
+        row += 2;
+        width -= n;
+    }
+    SkDebugf( "\n" );
+}
+
+void SkAAClip::debug(bool compress_y) const {
+    Iter iter(*this);
+    const int width = fBounds.width();
+
+    int y = fBounds.fTop;
+    while (!iter.done()) {
+        if (compress_y) {
+            dump_one_row(iter.data(), width, iter.bottom() - iter.top() + 1);
+        } else {
+            do {
+                dump_one_row(iter.data(), width, 0);
+            } while (++y < iter.bottom());
+        }
+        iter.next();
+    }
+}
 #endif
 
 ///////////////////////////////////////////////////////////////////////////////
 
 // Count the number of zeros on the left and right edges of the passed in
 // RLE row. If 'row' is all zeros return 'width' in both variables.
 static void count_left_right_zeros(const uint8_t* row, int width,
                                    int* leftZ, int* riteZ) {
     int zeros = 0;
     do {
@@ skipping 1956 matching lines @@
             rowMask.fBounds.fBottom = y + 1;
             fBlitter->blitMask(rowMask, rowMask.fBounds);
             src = (const void*)((const char*)src + srcRB);
         } while (++y < localStopY);
     } while (y < stopY);
 }
 
 const SkBitmap* SkAAClipBlitter::justAnOpaqueColor(uint32_t* value) {
     return NULL;
 }