Serialization of SkPictureImageFilter

src/core/SkPicture.cpp

 
 /*
  * Copyright 2007 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkPictureFlat.h"
@@ skipping 280 matching lines @@
         ) {
         return false;
     }
 
     if (pInfo != NULL) {
         *pInfo = info;
     }
     return true;
 }
 
+bool SkPicture::BufferIsSKP(SkFlattenableReadBuffer& buffer, SkPictInfo* pInfo) {
+    // Check magic bytes.
+    char magic[sizeof(kMagic)];
+    
+    if (!buffer.readByteArray(magic, sizeof(kMagic)) ||
+        (0 != memcmp(magic, kMagic, sizeof(kMagic)))) {
+        return false;
+    }
+
+    SkPictInfo info;
+    if (!buffer.readByteArray(&info, sizeof(SkPictInfo))) {
+        return false;
+    }
+
+    if (PICTURE_VERSION != info.fVersion
+#ifndef DELETE_THIS_CODE_WHEN_SKPS_ARE_REBUILT_AT_V16_AND_ALL_OTHER_INSTANCES_TOO

[Stephen White, 2014/01/15 14:59:02]

Considering that this will be the first time that pictures are serialized this
way, is this necessary? Is there a way to get an older version of a picture into
this new code?

[sugoi, 2014/01/15 16:49:22]

Done.

+        // V16 is backwards compatible with V15
+        && PRIOR_PICTURE_VERSION != info.fVersion  // TODO: remove when .skps regenerated
+#endif
+        ) {
+        return false;
+    }
+
+    if (pInfo != NULL) {
+        *pInfo = info;
+    }
+    return true;
+}
+
 SkPicture::SkPicture(SkPicturePlayback* playback, int width, int height)
     : fPlayback(playback)
     , fRecord(NULL)
     , fWidth(width)
     , fHeight(height) {}
 
 SkPicture* SkPicture::CreateFromStream(SkStream* stream, InstallPixelRefProc proc) {
     SkPictInfo info;
 
     if (!StreamIsSKP(stream, &info)) {
         return NULL;
     }
 
     SkPicturePlayback* playback;
     // Check to see if there is a playback to recreate.
     if (stream->readBool()) {
         playback = SkPicturePlayback::CreateFromStream(stream, info, proc);
         if (NULL == playback) {
             return NULL;
         }
     } else {
         playback = NULL;
     }
 
     return SkNEW_ARGS(SkPicture, (playback, info.fWidth, info.fHeight));
 }
 
+SkPicture* SkPicture::CreateFromBuffer(SkFlattenableReadBuffer& buffer) {
+    SkPictInfo info;
+
+    if (!BufferIsSKP(buffer, &info)) {
+        return NULL;
+    }
+
+    SkPicturePlayback* playback;
+    // Check to see if there is a playback to recreate.
+    if (buffer.readBool()) {
+        playback = SkPicturePlayback::CreateFromBuffer(buffer);
+        if (NULL == playback) {
+            return NULL;
+        }
+    } else {
+        playback = NULL;
+    }
+
+    return SkNEW_ARGS(SkPicture, (playback, info.fWidth, info.fHeight));
+}
+
 void SkPicture::serialize(SkWStream* stream, EncodeBitmap encoder) const {
     SkPicturePlayback* playback = fPlayback;
 
     if (NULL == playback && fRecord) {
         playback = SkNEW_ARGS(SkPicturePlayback, (*fRecord));
     }
 
     SkPictInfo info;
 
     info.fVersion = PICTURE_VERSION;
@@ skipping 17 matching lines @@
         playback->serialize(stream, encoder);
         // delete playback if it is a local version (i.e. cons'd up just now)
         if (playback != fPlayback) {
             SkDELETE(playback);
         }
     } else {
         stream->writeBool(false);
     }
 }
 
+void SkPicture::flatten(SkFlattenableWriteBuffer& buffer) const {
+    SkPicturePlayback* playback = fPlayback;
+
+    if (NULL == playback && fRecord) {
+        playback = SkNEW_ARGS(SkPicturePlayback, (*fRecord));
+    }
+
+    SkPictInfo info;
+
+    info.fVersion = PICTURE_VERSION;
+    info.fWidth = fWidth;
+    info.fHeight = fHeight;
+    info.fFlags = SkPictInfo::kCrossProcess_Flag;
+    // TODO: remove this flag, since we're always float (now)
+    info.fFlags |= SkPictInfo::kScalarIsFloat_Flag;
+
+    if (8 == sizeof(void*)) {
+        info.fFlags |= SkPictInfo::kPtrIs64Bit_Flag;
+    }
+
+    // Write 8 magic bytes to ID this file format.
+    SkASSERT(sizeof(kMagic) == 8);
+    buffer.writeByteArray(kMagic, sizeof(kMagic));
+
+    buffer.writeByteArray(&info, sizeof(info));
+    if (playback) {
+        buffer.writeBool(true);
+        playback->flatten(buffer);
+        // delete playback if it is a local version (i.e. cons'd up just now)
+        if (playback != fPlayback) {
+            SkDELETE(playback);
+        }
+    } else {
+        buffer.writeBool(false);
+    }
+}
+
 bool SkPicture::willPlayBackBitmaps() const {
     if (!fPlayback) return false;
     return fPlayback->containsBitmaps();
 }
 
 #ifdef SK_BUILD_FOR_ANDROID
 void SkPicture::abortPlayback() {
     if (NULL == fPlayback) {
         return;
     }
     fPlayback->abort();
 }
 #endif