SkMultiPictureDocument & SkMultiPictureDocumentReader

also, a new DM::Src.

motivation: To be used to test the printing pipeline in Chromium.

BUG=skia:5370

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2023593002

Review-Url: https://codereview.chromium.org/2023593002

10 files changed, 320 insertions, 34 deletions

diff --git a/dm/DM.cpp b/dm/DM.cpp
index 56c3b66be0..c4e7d15f8e 100644
--- a/dm/DM.cpp
+++ b/dm/DM.cpp
@@ -72,6 +72,8 @@ DEFINE_int32(shards, 1, "We're splitting source data into this many shards.");
 DEFINE_int32(shard,  0, "Which shard do I run?");
 DEFINE_bool(simpleCodec, false, "Only decode images to native scale");
 
+DEFINE_string(mskps, "", "Directory to read mskps from, or a single mskp file.");
+
 using namespace DM;
 using sk_gpu_test::GrContextFactory;
 using sk_gpu_test::GLTestContext;
@@ -702,6 +704,19 @@ static bool gather_srcs() {
         }
     }
 
+    for (int i = 0; i < FLAGS_mskps.count(); i++) {
+        const char* path = FLAGS_mskps[i];
+        if (sk_isdir(path)) {
+            SkOSFile::Iter it(path, "mskp");
+            for (SkString file; it.next(&file);) {
+                push_src("mskp", "",
+                         new MSKPSrc(SkOSPath::Join(path, file.c_str())));
+            }
+        } else {
+            push_src("mskp", "", new MSKPSrc(path));
+        }
+    }
+
     SkTArray<SkString> images;
     if (!CollectImages(FLAGS_images, &images)) {
         return false;
diff --git a/dm/DMSrcSink.cpp b/dm/DMSrcSink.cpp
index 356416035b..a1be0979fd 100644
--- a/dm/DMSrcSink.cpp
+++ b/dm/DMSrcSink.cpp
@@ -1007,6 +1007,41 @@ Name SKPSrc::name() const { return SkOSPath::Basename(fPath.c_str()); }
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
+MSKPSrc::MSKPSrc(Path path) : fPath(path) {
+    std::unique_ptr<SkStreamAsset> stream(SkStream::NewFromFile(fPath.c_str()));
+    (void)fReader.init(stream.get());
+}
+
+int MSKPSrc::pageCount() const { return fReader.pageCount(); }
+
+SkISize MSKPSrc::size() const { return this->size(0); }
+SkISize MSKPSrc::size(int i) const { return fReader.pageSize(i).toCeil(); }
+
+Error MSKPSrc::draw(SkCanvas* c) const { return this->draw(0, c); }
+Error MSKPSrc::draw(int i, SkCanvas* canvas) const {
+    std::unique_ptr<SkStreamAsset> stream(SkStream::NewFromFile(fPath.c_str()));
+    if (!stream) {
+        return SkStringPrintf("Unable to open file: %s", fPath.c_str());
+    }
+    if (fReader.pageCount() == 0) {
+        return SkStringPrintf("Unable to parse MultiPictureDocument file: %s", fPath.c_str());
+    }
+    if (i >= fReader.pageCount()) {
+        return SkStringPrintf("MultiPictureDocument page number out of range: %d", i);
+    }
+    sk_sp<SkPicture> page = fReader.readPage(stream.get(), i);
+    if (!page) {
+        return SkStringPrintf("SkMultiPictureDocumentReader failed on page %d: %s",
+                              i, fPath.c_str());
+    }
+    canvas->drawPicture(page);
+    return "";
+}
+
+Name MSKPSrc::name() const { return SkOSPath::Basename(fPath.c_str()); }
+
+/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
+
 Error NullSink::draw(const Src& src, SkBitmap*, SkWStream*, SkString*) const {
     SkAutoTDelete<SkCanvas> canvas(SkCreateNullCanvas());
     return src.draw(canvas);
@@ -1099,44 +1134,15 @@ static Error draw_skdocument(const Src& src, SkDocument* doc, SkWStream* dst) {
         return "Source has empty dimensions";
     }
     SkASSERT(doc);
-    int width  = src.size().width(),
-        height = src.size().height();
-
-    if (FLAGS_multiPage) {
-        // Print the given DM:Src to a document, breaking on 8.5x11 pages.
-        const int kLetterWidth = 612,  // 8.5 * 72
-                kLetterHeight = 792;   // 11 * 72
-        const SkRect letter = SkRect::MakeWH(SkIntToScalar(kLetterWidth),
-                                             SkIntToScalar(kLetterHeight));
-
-        int xPages = ((width - 1) / kLetterWidth) + 1;
-        int yPages = ((height - 1) / kLetterHeight) + 1;
-
-        for (int y = 0; y < yPages; ++y) {
-            for (int x = 0; x < xPages; ++x) {
-                int w = SkTMin(kLetterWidth, width - (x * kLetterWidth));
-                int h = SkTMin(kLetterHeight, height - (y * kLetterHeight));
-                SkCanvas* canvas =
-                        doc->beginPage(SkIntToScalar(w), SkIntToScalar(h));
-                if (!canvas) {
-                    return "SkDocument::beginPage(w,h) returned nullptr";
-                }
-                canvas->clipRect(letter);
-                canvas->translate(-letter.width() * x, -letter.height() * y);
-                Error err = src.draw(canvas);
-                if (!err.isEmpty()) {
-                    return err;
-                }
-                doc->endPage();
-            }
-        }
-    } else {
+    int pageCount = src.pageCount();
+    for (int i = 0; i < pageCount; ++i) {
+        int width = src.size(i).width(), height = src.size(i).height();
         SkCanvas* canvas =
                 doc->beginPage(SkIntToScalar(width), SkIntToScalar(height));
         if (!canvas) {
             return "SkDocument::beginPage(w,h) returned nullptr";
         }
-        Error err = src.draw(canvas);
+        Error err = src.draw(i, canvas);
         if (!err.isEmpty()) {
             return err;
         }
diff --git a/dm/DMSrcSink.h b/dm/DMSrcSink.h
index 42f0e6da36..395f59e1a9 100644
--- a/dm/DMSrcSink.h
+++ b/dm/DMSrcSink.h
@@ -15,6 +15,7 @@
 #include "SkBitmapRegionDecoder.h"
 #include "SkCanvas.h"
 #include "SkData.h"
+#include "SkMultiPictureDocumentReader.h"
 #include "SkPicture.h"
 #include "gm.h"
 
@@ -66,6 +67,11 @@ struct Src {
     virtual void modifyGrContextOptions(GrContextOptions* options) const {}
     virtual bool veto(SinkFlags) const { return false; }
 
+    virtual int pageCount() const { return 1; }
+    virtual Error SK_WARN_UNUSED_RESULT draw(int, SkCanvas* canvas) const {
+        return this->draw(canvas);
+    }
+    virtual SkISize size(int) const { return this->size(); }
     // Force Tasks using this Src to run on the main thread?
     virtual bool serial() const { return false; }
 };
@@ -243,6 +249,24 @@ private:
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
+class MSKPSrc : public Src {
+public:
+    explicit MSKPSrc(Path path);
+
+    int pageCount() const override;
+    Error draw(SkCanvas* c) const override;
+    Error draw(int, SkCanvas*) const override;
+    SkISize size() const override;
+    SkISize size(int) const override;
+    Name name() const override;
+
+private:
+    Path fPath;
+    SkMultiPictureDocumentReader fReader;
+};
+
+/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
+
 class NullSink : public Sink {
 public:
     NullSink() {}
diff --git a/gyp/dm.gypi b/gyp/dm.gypi
index 4a4f8ba313..d307c9c91b 100644
--- a/gyp/dm.gypi
+++ b/gyp/dm.gypi
@@ -24,7 +24,7 @@
     'skia_lib.gyp:skia_lib',
     'svg.gyp:svg',
     'tools.gyp:crash_handler',
-	'tools.gyp:picture_utils',
+    'tools.gyp:picture_utils',
     'tools.gyp:proc_stats',
     'tools.gyp:sk_tool_utils',
     'tools.gyp:url_data_manager',
@@ -43,6 +43,7 @@
     '../dm/DMJsonWriter.cpp',
     '../gm/gm.cpp',
 
+    '../src/utils/SkMultiPictureDocumentReader.cpp',
     '../tools/debugger/SkDebugCanvas.cpp',
     '../tools/debugger/SkDrawCommand.cpp',
     '../tools/debugger/SkJsonWriteBuffer.cpp',
diff --git a/gyp/utils.gypi b/gyp/utils.gypi
index ea12203cb5..fb8805eecd 100644
--- a/gyp/utils.gypi
+++ b/gyp/utils.gypi
@@ -54,6 +54,7 @@
         '<(skia_src_path)/utils/SkMatrix22.cpp',
         '<(skia_src_path)/utils/SkMatrix22.h',
         '<(skia_src_path)/utils/SkMeshUtils.cpp',
+        '<(skia_src_path)/utils/SkMultiPictureDocument.cpp',
         '<(skia_src_path)/utils/SkNinePatch.cpp',
         '<(skia_src_path)/utils/SkNWayCanvas.cpp',
         '<(skia_src_path)/utils/SkNullCanvas.cpp',
diff --git a/src/utils/SkMultiPictureDocument.cpp b/src/utils/SkMultiPictureDocument.cpp
new file mode 100644
index 0000000000..1cbf0aebc1
--- /dev/null
+++ b/src/utils/SkMultiPictureDocument.cpp
@@ -0,0 +1,106 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkMultiPictureDocument.h"
+#include "SkMultiPictureDocumentPriv.h"
+#include "SkPicture.h"
+#include "SkPictureRecorder.h"
+#include "SkStream.h"
+
+/*
+  File format:
+      BEGINNING_OF_FILE:
+        kMagic
+        uint32_t version_number
+        uint32_t page_count
+        {
+          uint64_t offset
+          float sizeX
+          float sizeY
+        } * page_count
+      FIRST_OFFSET:
+        skp file
+      SECOND_OFFSET:
+        skp file
+      ...
+      LAST_OFFSET:
+        skp file
+        "\nEndOfMultiPicture\n"
+*/
+
+namespace {
+static SkCanvas* trim(SkCanvas* canvas,
+                      SkScalar w, SkScalar h,
+                      const SkRect& trimBox) {
+    // Only trim if necessary.
+    if (trimBox != SkRect::MakeWH(w, h)) {
+        // All SkDocument implementations implement trimBox using a
+        // clip+translate.
+        canvas->clipRect(trimBox);
+        canvas->translate(trimBox.x(), trimBox.y());
+    }
+    return canvas;
+}
+
+struct NullWStream : public SkWStream {
+    NullWStream() : fN(0) {}
+    bool write(const void*, size_t n) override {
+        fN += n;
+        return true;
+    }
+    size_t bytesWritten() const override { return fN; }
+    size_t fN;
+};
+
+struct MultiPictureDocument final : public SkDocument {
+    SkPictureRecorder fPictureRecorder;
+    SkTArray<sk_sp<SkPicture>> fPages;
+    MultiPictureDocument(SkWStream* s, void (*d)(SkWStream*, bool))
+        : SkDocument(s, d) {}
+    ~MultiPictureDocument() { this->close(); }
+
+    SkCanvas* onBeginPage(SkScalar w, SkScalar h, const SkRect& c) override {
+        return trim(fPictureRecorder.beginRecording(w, h), w, h, c);
+    }
+    void onEndPage() override {
+        fPages.emplace_back(fPictureRecorder.finishRecordingAsPicture());
+    }
+    bool onClose(SkWStream* wStream) override {
+        SkASSERT(wStream);
+        SkASSERT(wStream->bytesWritten() == 0);
+        bool good = true;
+        good &= wStream->writeText(SkMultiPictureDocumentProtocol::kMagic);
+        good &= wStream->write32(SkToU32(1));  // version
+        good &= wStream->write32(SkToU32(fPages.count()));
+        uint64_t offset = wStream->bytesWritten();
+        offset += fPages.count() * sizeof(SkMultiPictureDocumentProtocol::Entry);
+        for (const auto& page : fPages) {
+            SkRect cullRect = page->cullRect();
+            // We recorded a picture at the origin.
+            SkASSERT(cullRect.x() == 0 && cullRect.y() == 0);
+            SkMultiPictureDocumentProtocol::Entry entry{
+                    offset, (float)cullRect.right(), (float)cullRect.bottom()};
+            good &= wStream->write(&entry, sizeof(entry));
+            NullWStream buffer;
+            page->serialize(&buffer);
+            offset += buffer.bytesWritten();
+        }
+        for (const auto& page : fPages) {
+            page->serialize(wStream);
+        }
+        SkASSERT(wStream->bytesWritten() == offset);
+        good &= wStream->writeText("\nEndOfMultiPicture\n");
+        fPages.reset();
+        return good;
+    }
+    void onAbort() override { fPages.reset(); }
+};
+}
+
+sk_sp<SkDocument> SkMakeMultiPictureDocument(SkWStream* wStream) {
+    return sk_make_sp<MultiPictureDocument>(wStream, nullptr);
+}
diff --git a/src/utils/SkMultiPictureDocument.h b/src/utils/SkMultiPictureDocument.h
new file mode 100644
index 0000000000..1da105e1b6
--- /dev/null
+++ b/src/utils/SkMultiPictureDocument.h
@@ -0,0 +1,16 @@
+/*
+ * 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 SkMultiPictureDocument_DEFINED
+#define SkMultiPictureDocument_DEFINED
+
+#include "SkDocument.h"
+
+/** Writes into an experimental, undocumented file format that is
+    useful for debugging documents printed via Skia. */
+SK_API sk_sp<SkDocument> SkMakeMultiPictureDocument(SkWStream* dst);
+
+#endif  // SkMultiPictureDocument_DEFINED
diff --git a/src/utils/SkMultiPictureDocumentPriv.h b/src/utils/SkMultiPictureDocumentPriv.h
new file mode 100644
index 0000000000..124dad7c6b
--- /dev/null
+++ b/src/utils/SkMultiPictureDocumentPriv.h
@@ -0,0 +1,23 @@
+/*
+ * 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 SkMultiPictureDocumentPriv_DEFINED
+#define SkMultiPictureDocumentPriv_DEFINED
+
+#include "stdint.h"
+
+namespace SkMultiPictureDocumentProtocol {
+static constexpr char kMagic[] = "Skia Multi-Picture Doc\n\n";
+
+struct Entry {
+    uint64_t offset;
+    float sizeX;
+    float sizeY;
+};
+}
+
+#endif  // SkMultiPictureDocumentPriv_DEFINED
diff --git a/src/utils/SkMultiPictureDocumentReader.cpp b/src/utils/SkMultiPictureDocumentReader.cpp
new file mode 100644
index 0000000000..6bc77bfc76
--- /dev/null
+++ b/src/utils/SkMultiPictureDocumentReader.cpp
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkMultiPictureDocumentPriv.h"
+#include "SkMultiPictureDocumentReader.h"
+#include "SkPicture.h"
+#include "SkStream.h"
+
+bool SkMultiPictureDocumentReader::init(SkStreamSeekable* stream) {
+    if (!stream) {
+        return false;
+    }
+    stream->seek(0);
+    const size_t size = sizeof(SkMultiPictureDocumentProtocol::kMagic) - 1;
+    char buffer[size];
+    if (size != stream->read(buffer, size) ||
+        0 != memcmp(SkMultiPictureDocumentProtocol::kMagic, buffer, size)) {
+        stream = nullptr;
+        return false;
+    }
+    bool good = true;
+    uint32_t versionNumber = stream->readU32();
+    if (versionNumber != 1) {
+        return false;
+    }
+    uint32_t pageCount = stream->readU32();
+    fSizes.reset(pageCount);
+    fOffsets.reset(pageCount);
+    for (uint32_t i = 0; i < pageCount; ++i) {
+        SkMultiPictureDocumentProtocol::Entry entry;
+        good &= sizeof(entry) == stream->read(&entry, sizeof(entry));
+        fSizes[i] = SkSize::Make(entry.sizeX, entry.sizeY);
+        good &= SkTFitsIn<size_t>(entry.offset);
+        fOffsets[i] = static_cast<size_t>(entry.offset);
+    }
+    return good;
+}
+
+sk_sp<SkPicture> SkMultiPictureDocumentReader::readPage(SkStreamSeekable* stream,
+                                                        int pageNumber) const {
+    SkASSERT(pageNumber >= 0);
+    SkASSERT(pageNumber < fOffsets.count());
+    SkAssertResult(stream->seek(fOffsets[pageNumber]));
+    return SkPicture::MakeFromStream(stream);
+}
diff --git a/src/utils/SkMultiPictureDocumentReader.h b/src/utils/SkMultiPictureDocumentReader.h
new file mode 100644
index 0000000000..8e0a630e52
--- /dev/null
+++ b/src/utils/SkMultiPictureDocumentReader.h
@@ -0,0 +1,45 @@
+/*
+ * 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 SkMultiPictureDocumentReader_DEFINED
+#define SkMultiPictureDocumentReader_DEFINED
+
+#include "../private/SkTArray.h"
+#include "SkPicture.h"
+#include "SkSize.h"
+#include "SkStream.h"
+
+/** A lightweight helper class for reading a Skia MultiPictureDocument. */
+class SkMultiPictureDocumentReader {
+public:
+    /** Initialize the MultiPictureDocument.  Does not take ownership
+        of the SkStreamSeekable. */
+    bool init(SkStreamSeekable*);
+
+    /** Return to factory settings. */
+    void reset() {
+        fSizes.reset();
+        fOffsets.reset();
+    }
+
+    /** Call this after calling init() */
+    int pageCount() const { return fSizes.count(); }
+
+    /** Deserialize a page from the stream.  Call init() first.  The
+        SkStreamSeekable doesn't need to be the same object, but
+        should point to the same information as before. */
+    sk_sp<SkPicture> readPage(SkStreamSeekable*, int) const;
+
+    /** Fetch the size of the given page, without deserializing the
+        entire page. */
+    SkSize pageSize(int i) const { return fSizes[i]; }
+
+private:
+    SkTArray<SkSize> fSizes;
+    SkTArray<size_t> fOffsets;
+};
+
+#endif  // SkMultiPictureDocumentReader_DEFINED