Enable automatic rescaling in bench_pictures

bench_pictures with "--device gpu" is failing because we're trying to allocate
too much GPU memory.  Move the recently-added scaling code into picture_utils
and share it between render_pictures and bench_pictures.
Review URL: https://codereview.appspot.com/6495125

git-svn-id: http://skia.googlecode.com/svn/trunk@5543 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 45 insertions, 0 deletions

diff --git a/tools/picture_utils.cpp b/tools/picture_utils.cpp
index b9bedbb504..2dd1f4ec45 100644
--- a/tools/picture_utils.cpp
+++ b/tools/picture_utils.cpp
@@ -6,9 +6,11 @@
  */
 
 #include "picture_utils.h"
+#include "SkCanvas.h"
 #include "SkColorPriv.h"
 #include "SkBitmap.h"
 #include "SkPicture.h"
+#include "SkRefCnt.h"
 #include "SkString.h"
 #include "SkStream.h"
 
@@ -90,4 +92,47 @@ namespace sk_tools {
         bitmap->allocPixels();
         bitmap->eraseColor(0);
     }
+
+    bool area_too_big(int w, int h, SkISize* newSize) {
+        // just a guess, based on what seems to fail on smaller android devices
+        static const int64_t kMaxAreaForMemory = 16 * 1024 * 1024;
+
+        if ((int64_t)w * h > kMaxAreaForMemory) {
+            do {
+                w >>= 1;
+                h >>= 1;
+            } while ((int64_t)w * h > kMaxAreaForMemory);
+            if (0 == w) {
+                w = 1;
+            }
+            if (0 == h) {
+                h = 1;
+            }
+            newSize->set(w, h);
+            return true;
+        }
+        return false;
+    }
+
+    void resize_if_needed(SkAutoTUnref<SkPicture>* aur) {
+        SkISize newSize;
+        SkPicture* picture = aur->get();
+        if (area_too_big(picture->width(), picture->height(), &newSize)) {
+            SkPicture* pic = SkNEW(SkPicture);
+            picture->ref();
+            aur->reset(pic);
+
+            SkCanvas* canvas = pic->beginRecording(newSize.width(),
+                                                   newSize.height());
+            SkScalar scale = SkIntToScalar(newSize.width()) / picture->width();
+            canvas->scale(scale, scale);
+            canvas->drawPicture(*picture);
+            pic->endRecording();
+
+            SkDebugf(
+                "... rescaling to [%d %d] to avoid overly large allocations\n",
+                newSize.width(), newSize.height());
+            picture->unref();
+        }
+    }
 }