This CL adds client.toDataURL which gets the contents

of the client area as a data url (which is a base64
encoded string of a png file)

data urls are part of the HTML5 standard and supported
by firefox, safari and chrome.
http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#dom-canvas-todataurl

That means you can now do this

var dataURL = client.toDataURL();
// make an IMG tag display the screenshot
someImgTag.src = dataURL;  
// use the IMG tag to draw into a canvas
someCanvasContext.drawImage(someImageTag, ...);

It also means there is no need for the test builds
anymore "test-dbg-d3d", "test-opt-d3d" etc as
toDataURL is part of the public API and can
therefore always be used to take screenshots
in any build.

I updated the selenium code to use it.

There are a few issues:

1) The GL version has the same limitations as taking
a screenshot before. Namely that the client area
must be on screen. We need to fix this.

2) We need to add support for origin-clean. See
https://tracker.corp.google.com/story/show/180334

Review URL: http://codereview.chromium.org/164130

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@22869 0039d316-1c4b-4281-b951-d872f2087c98

18 files changed, 111 insertions, 100 deletions

diff --git a/o3d/core/cross/bitmap.cc b/o3d/core/cross/bitmap.cc
index 8069451..cdccc66 100644
--- a/o3d/core/cross/bitmap.cc
+++ b/o3d/core/cross/bitmap.cc
@@ -146,8 +146,8 @@ void Bitmap::SetRect(
 
   uint8* dst =
       GetMipData(level) +
-      image::ComputeMipChainSize(mip_width, dst_top, format(), 1) +
-      image::ComputeMipChainSize(dst_left, 1, format(), 1);
+      image::ComputePitch(format(), mip_width) * dst_top +
+      image::ComputePitch(format(), dst_left);
 
   const uint8* src = static_cast<const uint8*>(src_data);
   if (!compressed) {
diff --git a/o3d/core/cross/bitmap.h b/o3d/core/cross/bitmap.h
index 5bd3687..a86b76a 100644
--- a/o3d/core/cross/bitmap.h
+++ b/o3d/core/cross/bitmap.h
@@ -242,13 +242,10 @@ class Bitmap : public ParamObject {
   // from a flippable format back to a DXT format.

   void FlipVertically();

 

-  // Saves to a PNG file. The image must be of the ARGB8 format, be a 2D image

-  // with no mip-maps (only the base level).

-  // Parameters:

-  //   filename: the name of the file to into.

+  // Returns the contents of the bitmap as a data URL

   // Returns:

-  //   true if successful.

-  bool SaveToPNGFile(const char* filename);

+  //   A data url that represents the content of the bitmap.

+  String ToDataURL();

 

   // Checks that the alpha channel for the entire bitmap is 1.0

   bool CheckAlphaIsOne() const;

diff --git a/o3d/core/cross/bitmap_png.cc b/o3d/core/cross/bitmap_png.cc
index 770ced0..047f585 100644
--- a/o3d/core/cross/bitmap_png.cc
+++ b/o3d/core/cross/bitmap_png.cc
@@ -37,6 +37,7 @@
 
 #include <fstream>
 #include "core/cross/bitmap.h"
+#include "core/cross/error.h"
 #include "core/cross/types.h"
 #include "utils/cross/file_path_utils.h"
 #include "base/file_path.h"
@@ -44,22 +45,38 @@
 #include "import/cross/memory_buffer.h"
 #include "import/cross/memory_stream.h"
 #include "png.h"
+#include "utils/cross/dataurl.h"
 
 using file_util::OpenFile;
 using file_util::CloseFile;
 
 namespace o3d {
 
+namespace {
+
 // Helper function for LoadFromPNGFile that converts a stream into the
 // necessary abstract byte reading function.
-static void stream_read_data(png_structp png_ptr,
-                             png_bytep data,
-                             png_size_t length) {
+void StreamReadData(png_structp png_ptr, png_bytep data, png_size_t length) {
   MemoryReadStream *stream =
     static_cast<MemoryReadStream*>(png_get_io_ptr(png_ptr));
   stream->Read(data, length);
 }
 
+// Helper function for ToDataURL that converts a stream into the necessary
+// abstract byte writing function.
+void StreamWriteData(png_structp png_ptr, png_bytep data, png_size_t length) {
+  std::vector<uint8>* stream =
+     static_cast<std::vector<uint8>*>(png_get_io_ptr(png_ptr));
+  stream->insert(stream->end(),
+                 static_cast<uint8*>(data),
+                 static_cast<uint8*>(data) + length);
+}
+
+// Because libpng requires a flush function according to the docs.
+void StreamFlush(png_structp png_ptr) {
+}
+
+}  // anonymous namespace
 
 // Loads the raw RGB data from a compressed PNG file.
 bool Bitmap::LoadFromPNGStream(MemoryReadStream *stream,
@@ -117,7 +134,7 @@ bool Bitmap::LoadFromPNGStream(MemoryReadStream *stream,
   }
 
   // Set up our STL stream input control
-  png_set_read_fn(png_ptr, stream, &stream_read_data);
+  png_set_read_fn(png_ptr, stream, &StreamReadData);
 
   // We have already read some of the signature, advance the pointer.
   png_set_sig_bytes(png_ptr, sizeof(magic));
@@ -263,27 +280,17 @@ bool Bitmap::LoadFromPNGStream(MemoryReadStream *stream,
   return true;
 }
 
-// Saves the BGRA data from a compressed PNG file.
-bool Bitmap::SaveToPNGFile(const char* filename) {
-  if (format_ != Texture::ARGB8) {
-    DLOG(ERROR) << "Can only save ARGB8 images.";
-    return false;
-  }
-  if (num_mipmaps_ != 1 || is_cubemap_) {
-    DLOG(ERROR) << "Only 2D images with only the base level can be saved.";
-    return false;
-  }
-  FILE *fp = fopen(filename, "wb");
-  if (!fp) {
-    DLOG(ERROR) << "Could not open file " << filename << " for writing.";
-    return false;
-  }
+namespace {
+
+bool CreatePNGInUInt8Vector(const Bitmap& bitmap, std::vector<uint8>* buffer) {
+  DCHECK(bitmap.format() == Texture::ARGB8);
+  DCHECK(bitmap.num_mipmaps() == 1);
+  DCHECK(!bitmap.is_cubemap());
 
   png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL,
                                                 NULL, NULL);
   if (!png_ptr) {
     DLOG(ERROR) << "Could not create PNG structure.";
-    fclose(fp);
     return false;
   }
 
@@ -291,26 +298,27 @@ bool Bitmap::SaveToPNGFile(const char* filename) {
   if (!info_ptr) {
     DLOG(ERROR) << "Could not create PNG info structure.";
     png_destroy_write_struct(&png_ptr,  png_infopp_NULL);
-    fclose(fp);
     return false;
   }
 
-  scoped_array<png_bytep> row_pointers(new png_bytep[height_]);
-  for (int i = 0; i < height_; ++i) {
-    row_pointers[height_-1-i] = image_data_.get() + i * width_ * 4;
+  unsigned width = bitmap.width();
+  unsigned height = bitmap.height();
+  scoped_array<png_bytep> row_pointers(new png_bytep[height]);
+  for (int i = 0; i < height; ++i) {
+    row_pointers[height - 1 - i] = bitmap.GetMipData(0) + i * width * 4;
   }
 
   if (setjmp(png_jmpbuf(png_ptr))) {
     // If we get here, we had a problem reading the file.
-    DLOG(ERROR) << "Error while writing file " << filename << ".";
+    DLOG(ERROR) << "Error while getting dataURL.";
     png_destroy_write_struct(&png_ptr, &info_ptr);
-    fclose(fp);
     return false;
   }
 
-  png_init_io(png_ptr, fp);
+  // Set up our STL stream output.
+  png_set_write_fn(png_ptr, buffer, &StreamWriteData, &StreamFlush);
 
-  png_set_IHDR(png_ptr, info_ptr, width_, height_, 8,
+  png_set_IHDR(png_ptr, info_ptr, width, height, 8,
                PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE,
                PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
   png_set_bgr(png_ptr);
@@ -318,8 +326,27 @@ bool Bitmap::SaveToPNGFile(const char* filename) {
   png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, png_voidp_NULL);
 
   png_destroy_write_struct(&png_ptr, &info_ptr);
-  fclose(fp);
-  return true;
+}
+
+}  // anonymous namespace
+
+String Bitmap::ToDataURL() {
+  if (format_ != Texture::ARGB8) {
+    O3D_ERROR(service_locator()) << "Can only get data URL from ARGB8 images.";
+    return dataurl::kEmptyDataURL;
+  }
+  if (num_mipmaps_ != 1 || is_cubemap_) {
+    O3D_ERROR(service_locator()) <<
+        "Can only get data URL from 2d images with no mips.";
+    return dataurl::kEmptyDataURL;
+  }
+
+  std::vector<uint8> stream;
+  if (!CreatePNGInUInt8Vector(*this, &stream)) {
+    return dataurl::kEmptyDataURL;
+  }
+
+  return dataurl::ToDataURL("image/png", &stream[0], stream.size());
 }
 
 }  // namespace o3d
diff --git a/o3d/core/cross/client.cc b/o3d/core/cross/client.cc
index 7b70496..cfbce23 100644
--- a/o3d/core/cross/client.cc
+++ b/o3d/core/cross/client.cc
@@ -55,6 +55,7 @@
 #include "core/cross/profiler.h"
 #include "utils/cross/string_writer.h"
 #include "utils/cross/json_writer.h"
+#include "utils/cross/dataurl.h"
 
 #ifdef OS_WIN
 #include "core/cross/core_metrics.h"
@@ -401,12 +402,17 @@ void Client::InvalidateAllParameters() {
   evaluation_counter_->InvalidateAllParameters();
 }
 
-bool Client::SaveScreen(const String& file_name) {
+String Client::ToDataURL() {
   if (!renderer_.IsAvailable()) {
     O3D_ERROR(service_locator_) << "No Render Device Available";
-    return false;
+    return dataurl::kEmptyDataURL;
   } else {
-    return renderer_->SaveScreen(file_name);
+    Bitmap::Ref bitmap(renderer_->TakeScreenshot());
+    if (bitmap.IsNull()) {
+      return dataurl::kEmptyDataURL;
+    } else {
+      return bitmap->ToDataURL();
+    }
   }
 }
 
diff --git a/o3d/core/cross/client.h b/o3d/core/cross/client.h
index b7de85c..153e354 100644
--- a/o3d/core/cross/client.h
+++ b/o3d/core/cross/client.h
@@ -395,9 +395,8 @@ class Client {
   // Dumps all profiler state to a string.
   String ProfileToString();
 
-  // Saves a png screenshot of the display buffer.
-  // Returns true on success and false on failure.
-  bool SaveScreen(const String& file_name);
+  // Reutrns a data: URL of the client area in png format.
+  String ToDataURL();
 
   // This class is intended to be used on the stack, such that the variable gets
   // incremented on scope entry and decremented on scope exit.  It's currently
diff --git a/o3d/core/cross/command_buffer/renderer_cb.cc b/o3d/core/cross/command_buffer/renderer_cb.cc
index 493da78..9de0617 100644
--- a/o3d/core/cross/command_buffer/renderer_cb.cc
+++ b/o3d/core/cross/command_buffer/renderer_cb.cc
@@ -368,9 +368,8 @@ void RendererCB::SetViewportInPixels(int left,
   helper_->AddCommand(command_buffer::SET_VIEWPORT, 6, args);
 }
 
-bool RendererCB::SaveScreen(const String& file_name) {
-  // TODO
-  return false;
+Bitmap::Ref RendererCB::TakeScreenshot() {
+  return Bitmap::Ref();
 }
 
 const int* RendererCB::GetRGBAUByteNSwizzleTable() {
diff --git a/o3d/core/cross/command_buffer/renderer_cb.h b/o3d/core/cross/command_buffer/renderer_cb.h
index df13f9b..e7f8963 100644
--- a/o3d/core/cross/command_buffer/renderer_cb.h
+++ b/o3d/core/cross/command_buffer/renderer_cb.h
@@ -141,9 +141,8 @@ class RendererCB : public Renderer {
     return RenderDepthStencilSurface::Ref();
   }
 
-  // Saves a png screenshot.
-  // Returns true on success and false on failure.
-  virtual bool SaveScreen(const String& file_name);
+  // Overridden from Renderer.
+  virtual Bitmap::Ref TakeScreenshot();
 
   // Gets the allocator for vertex buffer IDs.
   IdAllocator &vertex_buffer_ids() { return vertex_buffer_ids_; }
diff --git a/o3d/core/cross/command_buffer/texture_cb.h b/o3d/core/cross/command_buffer/texture_cb.h
index e000a8e..c08cfcd 100644
--- a/o3d/core/cross/command_buffer/texture_cb.h
+++ b/o3d/core/cross/command_buffer/texture_cb.h
@@ -32,8 +32,8 @@
 
 // This file contains the declarations for Texture2DCB and TextureCUBECB.
 
-#ifndef O3D_CORE_CROSS_COMMAND_BUFFER_TEXTURE_CB_H__
-#define O3D_CORE_CROSS_COMMAND_BUFFER_TEXTURE_CB_H__
+#ifndef O3D_CORE_CROSS_COMMAND_BUFFER_TEXTURE_CB_H_
+#define O3D_CORE_CROSS_COMMAND_BUFFER_TEXTURE_CB_H_
 
 // Precompiled header comes before everything else.
 #include "core/cross/precompile.h"
@@ -212,4 +212,4 @@ class TextureCUBECB : public TextureCUBE {
 
 }  // namespace o3d
 
-#endif  // O3D_CORE_CROSS_COMMAND_BUFFER_TEXTURE_CB_H__
+#endif  // O3D_CORE_CROSS_COMMAND_BUFFER_TEXTURE_CB_H_
diff --git a/o3d/core/cross/gl/renderer_gl.cc b/o3d/core/cross/gl/renderer_gl.cc
index c22cda3..4a8b215 100644
--- a/o3d/core/cross/gl/renderer_gl.cc
+++ b/o3d/core/cross/gl/renderer_gl.cc
@@ -1560,10 +1560,7 @@ RenderDepthStencilSurface::Ref RendererGL::CreateDepthStencilSurface(
                                       height));
 }
 
-// Saves a png screenshot 'file_name.png'.
-// Returns true on success and false on failure.
-bool RendererGL::SaveScreen(const String& file_name) {
-#ifdef TESTING
+Bitmap::Ref RendererGL::TakeScreenshot() {;
   MakeCurrentLazy();
   Bitmap::Ref bitmap = Bitmap::Ref(new Bitmap(service_locator()));
   bitmap->Allocate(Texture::ARGB8, width(), height(), 1, false);
@@ -1574,16 +1571,7 @@ bool RendererGL::SaveScreen(const String& file_name) {
   // might exhibit suprise translucency.
   ::glReadPixels(0, 0, width(), height(), GL_BGRA, GL_UNSIGNED_BYTE,
                  bitmap->image_data());
-  bool result = bitmap->SaveToPNGFile((file_name + ".png").c_str());
-  if (!result) {
-    O3D_ERROR(service_locator())
-        << "Failed to save screen into " << file_name;
-  }
-  return result;
-#else
-  // Not a test build, always return false.
-  return false;
-#endif
+  return bitmap;
 }
 
 const int* RendererGL::GetRGBAUByteNSwizzleTable() {
diff --git a/o3d/core/cross/gl/renderer_gl.h b/o3d/core/cross/gl/renderer_gl.h
index 24d8d01..534ea9c 100644
--- a/o3d/core/cross/gl/renderer_gl.h
+++ b/o3d/core/cross/gl/renderer_gl.h
@@ -144,9 +144,8 @@ class RendererGL : public Renderer {
       int width,
       int height);
 
-  // Saves a png screenshot 'file_name.png'.
-  // Returns true on success and false on failure.
-  virtual bool SaveScreen(const String& file_name);
+  // Overridden from Renderer.
+  virtual Bitmap::Ref TakeScreenshot();
 
   // Overridden from Renderer.
   virtual const int* GetRGBAUByteNSwizzleTable();
diff --git a/o3d/core/cross/gl/texture_gl.h b/o3d/core/cross/gl/texture_gl.h
index 6b97b7f..567bf2b 100644
--- a/o3d/core/cross/gl/texture_gl.h
+++ b/o3d/core/cross/gl/texture_gl.h
@@ -32,8 +32,8 @@
 
 // This file contains the declarations for Texture2DGL and TextureCUBEGL.
 
-#ifndef O3D_CORE_CROSS_GL_TEXTURE_GL_H__
-#define O3D_CORE_CROSS_GL_TEXTURE_GL_H__
+#ifndef O3D_CORE_CROSS_GL_TEXTURE_GL_H_
+#define O3D_CORE_CROSS_GL_TEXTURE_GL_H_
 
 // Precompiled header comes before everything else.
 #include "core/cross/precompile.h"
@@ -235,4 +235,4 @@ class TextureCUBEGL : public TextureCUBE {
 
 }  // namespace o3d
 
-#endif  // O3D_CORE_CROSS_GL_TEXTURE_GL_H__
+#endif  // O3D_CORE_CROSS_GL_TEXTURE_GL_H_
diff --git a/o3d/core/cross/gl/utils_gl.h b/o3d/core/cross/gl/utils_gl.h
index b6b87ff..a7af934 100644
--- a/o3d/core/cross/gl/utils_gl.h
+++ b/o3d/core/cross/gl/utils_gl.h
@@ -30,8 +30,8 @@
  */
 
 
-#ifndef O3D_CORE_CROSS_GL_UTILS_GL_H__
-#define O3D_CORE_CROSS_GL_UTILS_GL_H__
+#ifndef O3D_CORE_CROSS_GL_UTILS_GL_H_
+#define O3D_CORE_CROSS_GL_UTILS_GL_H_
 
 #include "base/basictypes.h"
 #include "core/cross/stream.h"
@@ -44,4 +44,4 @@ Stream::Semantic GLVertexAttributeToStream(const unsigned int attr, int *index);
 
 }  // namespace o3d
 
-#endif  // O3D_CORE_CROSS_GL_UTILS_GL_H__
+#endif  // O3D_CORE_CROSS_GL_UTILS_GL_H_
diff --git a/o3d/core/cross/image_utils.h b/o3d/core/cross/image_utils.h
index 12f29b8..2b6212e 100644
--- a/o3d/core/cross/image_utils.h
+++ b/o3d/core/cross/image_utils.h
@@ -59,8 +59,7 @@ enum ImageFileType {
 unsigned int GetNumComponentsForFormat(Texture::Format format);

 

 inline bool CheckImageDimensions(unsigned int width, unsigned int height) {

-  return width > 0 && height > 0 &&

-      width <= kMaxImageDimension && height <= kMaxImageDimension;

+  return width <= kMaxImageDimension && height <= kMaxImageDimension;

 }

 

 // Gets the number of mip-maps required for a full chain starting at

diff --git a/o3d/core/cross/image_utils_test.cc b/o3d/core/cross/image_utils_test.cc
index 99edc489..4f6a1c3 100644
--- a/o3d/core/cross/image_utils_test.cc
+++ b/o3d/core/cross/image_utils_test.cc
@@ -41,16 +41,14 @@ namespace o3d {
 class ImageTest : public testing::Test {
 };
 
-TEST_F(ImageTest, CheckImageDimensions) {
-  EXPECT_TRUE(image::CheckImageDimensions(1u, 1u));
-  EXPECT_FALSE(image::CheckImageDimensions(0u, 1u));
-  EXPECT_FALSE(image::CheckImageDimensions(1u, 0u));
-  EXPECT_TRUE(image::CheckImageDimensions(image::kMaxImageDimension,
-                                          image::kMaxImageDimension));
-  EXPECT_FALSE(image::CheckImageDimensions(0u, image::kMaxImageDimension));
-  EXPECT_FALSE(image::CheckImageDimensions(image::kMaxImageDimension, 0u));
-}
-
+TEST_F(ImageTest, CheckImageDimensions) {

+  EXPECT_TRUE(image::CheckImageDimensions(1u, 1u));

+  EXPECT_TRUE(image::CheckImageDimensions(image::kMaxImageDimension,

+                                          image::kMaxImageDimension));

+  EXPECT_FALSE(image::CheckImageDimensions(0u, image::kMaxImageDimension + 1));

+  EXPECT_FALSE(image::CheckImageDimensions(image::kMaxImageDimension + 1, 0u));

+}

+

 TEST_F(ImageTest, ComputeMipMapCount) {
   EXPECT_EQ(image::ComputeMipMapCount(1, 1), 1u);
   EXPECT_EQ(image::ComputeMipMapCount(2, 2), 2u);
@@ -301,3 +299,4 @@ TEST_F(ImageTest, GetFileTypeFromMimeType) {
 
 }  // namespace
 
+

diff --git a/o3d/core/cross/object_base.h b/o3d/core/cross/object_base.h
index 9a174c0..b4939c1 100644
--- a/o3d/core/cross/object_base.h
+++ b/o3d/core/cross/object_base.h
@@ -33,8 +33,8 @@
 // This file contains the declaration of the ObjectBase class and definitions
 // for the macros used to define the O3D object classes.
 
-#ifndef O3D_CORE_CROSS_OBJECT_BASE_H__
-#define O3D_CORE_CROSS_OBJECT_BASE_H__
+#ifndef O3D_CORE_CROSS_OBJECT_BASE_H_
+#define O3D_CORE_CROSS_OBJECT_BASE_H_
 
 #include <vector>
 
@@ -240,4 +240,4 @@ typedef std::vector<ObjectBase*> ObjectBaseArray;
 
 }  // namespace o3d
 
-#endif  // O3D_CORE_CROSS_OBJECT_BASE_H__
+#endif  // O3D_CORE_CROSS_OBJECT_BASE_H_
diff --git a/o3d/core/cross/precompile.h b/o3d/core/cross/precompile.h
index bc9ba64..3e11e99 100644
--- a/o3d/core/cross/precompile.h
+++ b/o3d/core/cross/precompile.h
@@ -33,8 +33,8 @@
 // This file contains includes for common headers used by O3D files.  It
 // is used for pre-compiled header support.
 
-#ifndef O3D_CORE_CROSS_PRECOMPILE_H__
-#define O3D_CORE_CROSS_PRECOMPILE_H__
+#ifndef O3D_CORE_CROSS_PRECOMPILE_H_
+#define O3D_CORE_CROSS_PRECOMPILE_H_
 
 #include <build/build_config.h>
 
@@ -63,4 +63,4 @@
 #include <map>
 #include <vector>
 
-#endif  // O3D_CORE_CROSS_PRECOMPILE_H__
+#endif  // O3D_CORE_CROSS_PRECOMPILE_H_
diff --git a/o3d/core/cross/renderer.h b/o3d/core/cross/renderer.h
index 15717ed..d766b24 100644
--- a/o3d/core/cross/renderer.h
+++ b/o3d/core/cross/renderer.h
@@ -364,9 +364,8 @@ class Renderer {
       int width,
       int height) = 0;
 
-  // Saves a png screenshot.
-  // Returns true on success and false on failure.
-  virtual bool SaveScreen(const String& file_name) = 0;
+  // Returns the screen as a Bitmap. Will return a null reference on error.
+  virtual Bitmap::Ref TakeScreenshot() = 0;
 
   ServiceLocator* service_locator() const { return service_locator_; }
 
diff --git a/o3d/core/cross/sampler.h b/o3d/core/cross/sampler.h
index 20ead52..c6dcf54 100644
--- a/o3d/core/cross/sampler.h
+++ b/o3d/core/cross/sampler.h
@@ -32,8 +32,8 @@
 
 // This file contains the declaration for the Sampler class.
 
-#ifndef O3D_CORE_CROSS_SAMPLER_H__
-#define O3D_CORE_CROSS_SAMPLER_H__
+#ifndef O3D_CORE_CROSS_SAMPLER_H_
+#define O3D_CORE_CROSS_SAMPLER_H_
 
 #include "core/cross/param_object.h"
 #include "core/cross/param.h"
@@ -204,4 +204,4 @@ class ParamSampler : public TypedRefParam<Sampler> {
 
 }  // namespace o3d
 
-#endif  // O3D_CORE_CROSS_SAMPLER_H__
+#endif  // O3D_CORE_CROSS_SAMPLER_H_