WebGraphicsContext3D* Canvas2DLayerBridge::context()
{
// Check on m_layer is necessary because context() may be called during
// the destruction of m_layer
if (m_layer && !m_destructionInProgress)
checkSurfaceValid(); // To ensure rate limiter is disabled if context is lost.
return m_contextProvider ? m_contextProvider->context3d() : 0;
}
PassRefPtr<SkImage> Canvas2DLayerBridge::newImageSnapshot()
{
if (!checkSurfaceValid())
return nullptr;
flush();
// A readback operation may alter the texture parameters, which may affect
// the compositor's behavior. Therefore, we must trigger copy-on-write
// even though we are not technically writing to the texture, only to its
// parameters.
m_surface->notifyContentWillChange(SkSurface::kRetain_ContentChangeMode);
return adoptRef(m_surface->newImageSnapshot());
}
void Canvas2DLayerBridge::prepareForDraw()
{
ASSERT(!m_destructionInProgress);
ASSERT(m_layer);
if (!checkSurfaceValid()) {
if (m_canvas) {
// drop pending commands because there is no surface to draw to
m_canvas->silentFlush();
}
return;
}
}
Platform3DObject Canvas2DLayerBridge::getBackingTexture()
{
ASSERT(!m_destructionInProgress);
if (!checkSurfaceValid())
return 0;
m_canvas->flush();
context()->flush();
GrRenderTarget* renderTarget = m_canvas->getTopDevice()->accessRenderTarget();
if (renderTarget) {
return renderTarget->asTexture()->getTextureHandle();
}
return 0;
}
bool Canvas2DLayerBridge::prepareMailbox(WebExternalTextureMailbox* outMailbox, WebExternalBitmap* bitmap)
{
ASSERT(isAccelerated());
if (m_destructionInProgress) {
// It can be hit in the following sequence.
// 1. Canvas draws something.
// 2. The compositor begins the frame.
// 3. Javascript makes a context be lost.
// 4. Here.
return false;
}
if (bitmap) {
// Using accelerated 2d canvas with software renderer, which
// should only happen in tests that use fake graphics contexts
// or in Android WebView in software mode. In this case, we do
// not care about producing any results for this canvas.
skipQueuedDrawCommands();
m_lastImageId = 0;
return false;
}
if (!checkSurfaceValid())
return false;
WebGraphicsContext3D* webContext = context();
RefPtr<SkImage> image = newImageSnapshot(PreferAcceleration);
// Early exit if canvas was not drawn to since last prepareMailbox
GLenum filter = m_filterQuality == kNone_SkFilterQuality ? GL_NEAREST : GL_LINEAR;
if (image->uniqueID() == m_lastImageId && filter == m_lastFilter)
return false;
m_lastImageId = image->uniqueID();
m_lastFilter = filter;
{
MailboxInfo tmp;
tmp.m_image = image;
tmp.m_parentLayerBridge = this;
m_mailboxes.prepend(tmp);
}
MailboxInfo& mailboxInfo = m_mailboxes.first();
mailboxInfo.m_mailbox.nearestNeighbor = filter == GL_NEAREST;
GrContext* grContext = m_contextProvider->grContext();
if (!grContext)
return true; // for testing: skip gl stuff when using a mock graphics context.
// Need to flush skia's internal queue because texture is about to be accessed directly
grContext->flush();
ASSERT(image->getTexture());
// Because of texture sharing with the compositor, we must invalidate
// the state cached in skia so that the deferred copy on write
// in SkSurface_Gpu does not make any false assumptions.
mailboxInfo.m_image->getTexture()->textureParamsModified();
webContext->bindTexture(GL_TEXTURE_2D, mailboxInfo.m_image->getTexture()->getTextureHandle());
webContext->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filter);
webContext->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filter);
webContext->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
webContext->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
// Re-use the texture's existing mailbox, if there is one.
if (image->getTexture()->getCustomData()) {
ASSERT(image->getTexture()->getCustomData()->size() == sizeof(mailboxInfo.m_mailbox.name));
memcpy(&mailboxInfo.m_mailbox.name[0], image->getTexture()->getCustomData()->data(), sizeof(mailboxInfo.m_mailbox.name));
} else {
context()->genMailboxCHROMIUM(mailboxInfo.m_mailbox.name);
RefPtr<SkData> mailboxNameData = adoptRef(SkData::NewWithCopy(&mailboxInfo.m_mailbox.name[0], sizeof(mailboxInfo.m_mailbox.name)));
image->getTexture()->setCustomData(mailboxNameData.get());
webContext->produceTextureCHROMIUM(GL_TEXTURE_2D, mailboxInfo.m_mailbox.name);
}
if (isHidden()) {
// With hidden canvases, we release the SkImage immediately because
// there is no need for animations to be double buffered.
mailboxInfo.m_image.clear();
} else {
// FIXME: We'd rather insert a syncpoint than perform a flush here,
// but currentlythe canvas will flicker if we don't flush here.
webContext->flush();
// mailboxInfo.m_mailbox.syncPoint = webContext->insertSyncPoint();
}
webContext->bindTexture(GL_TEXTURE_2D, 0);
// Because we are changing the texture binding without going through skia,
// we must dirty the context.
grContext->resetContext(kTextureBinding_GrGLBackendState);
*outMailbox = mailboxInfo.m_mailbox;
return true;
}
PassRefPtr<SkImage> Canvas2DLayerBridge::newImageSnapshot()
{
if (!checkSurfaceValid())
return nullptr;
return adoptRef(m_canvas->newImageSnapshot());
}
