How does this handles accelerated graphics?

Nice question :) There are 3 ways to create a canvas: 1) canvas for offscreen rendering. In this case it must be rasterized in order to be displayed on the screen. (requres pixel copying) 2) canvas for existing pixel buffer. In this case every draw operation directly manipulates pixels. For example there is a way to get a pointer to pixel buffer of SDL Window and create sparta canvas that would wrap it (no pixel copying required, very fast). 3) canvas for GL context. For example we could create an SDL window with OpenGL support, get GLContext and create canvas that would operate on it. (fast but a bit complicated). First way can result in either software or hardware rendering. For example on Mac users can choose one of the following backends: CoreGraphics CPU or CoreGraphics GPU, Skia CPU or Skia GPU and even Cairo. Second way does not allow to use GPU Accelerated backends, since canvas is created for pixel buffer. On Mac it is CoreGraphics CPU, Skia CPU or Cairo. Third way actually allows to create GPU accelerated canvas. For example Skia GPU renders everything using OpenGL. It is supported on all platforms: windows, linux, mac, android, iOS. The most simple way to create a new canvas is:

canvas := MozCanvas extent: 500@400.

Behind the scenes it chooses the best backend for current platform: D2D1 on Windows, CoreGraphics on Mac and Skia+X11 mixture on Linux. Important to mention that Sparta allows developers to manually select which backend to use. Cheers, Alex On 5 September 2016 at 14:51, philippe.back@highoctane.be < philippe.back@gmail.com> wrote:

Sweet.

How does this handles accelerated graphics?

Phil

Le 5 sept. 2016 11:52, "Aliaksei Syrel" <alex.syrel@gmail.com> a écrit :

...

Hi

I am happy to announce the release of Sparta v1.0 for Pharo 5 and Pharo 6. https://github.com/syrel/Sparta/tree/v1.0 For a moment only Linux and Mac are supported.

It can be bootstrapped with the following script:

Metacello new baseline: 'Sparta'; repository: 'github://syrel/sparta:v1.0/src'; load: #file:core

(on linux install 32bit libgtk-2, lingtk-3 and libstdc++) (script for ubuntu http://ws.stfx.eu/IEAWCUC18BH)

Sparta is an almost stateless vector graphics API for Pharo that provides bindings to the Moz2D rendering backend. Moz2D is the extracted graphical engine from Mozilla Firefox compiled as standalone shared library together with the extern C bindings required to call the engine from Pharo.

- developed with the help of Iceberg <https://github.com/npasserini/iceberg> (thanks!) on Github. - integrated into travis-ci <https://travis-ci.org/syrel/Sparta> using smalltalkCI <https://github.com/hpi-swa/smalltalkCI> (great job!). - documented using Pillar <https://github.com/pillar-markup/pillar> (so better!) syntax.

Cheers, Alex

Moz2D is used in Firefox to render webpages. For us it means that it supports all latest web features (concerning graphics) and allows us to finally implement the whole SVG standard.

"Why would one use it rather than the other existing Pharo libraries/wrappers?"

As far as I know there are two 2D libraries in Pharo: BitBlt and Athens (backend Cairo). Obviously BitBlt does not fit all our needs :) Athens is nice vector graphics abstraction. However, it does not support shadows, filters, clipping by arbitrary path, only works in global coordinates and has primitive text rendering. All those features were not necessary at the time it was developed. Another problem is statefullness of Athens (state is shared between draw operation) which does not fit so good when it comes to the rendering of an element tree. There is a modern trend to move from statefull to stateless frameworks. It is almost impossible to extend Athens without breaking user applications that use it. So, Sparta is Athens2 that adds support of all mentioned features. It is inspired and based on amazing work of Igor Stasenko. In Pharo we have bindings to Cairo. Which is old, lacks on features and no more maintained so good as it was before. To be performant we need to use native backends on every platform: D2D1 on Windows, X11 on Linux, CoreGraphics on Mac. Just imagine how much work is needed to implement bindings for every mentioned backend :) And do not forget that CoreGraphics is Object-C and can not be directly called through FFI, it has to be wrapped in C first... With Moz2D we get them all out of box for fee :) Cheers Alex On Sep 5, 2016 16:28, "Sean P. DeNigris" <sean@clipperadams.com> wrote:

Aliaksei Syrel wrote

...

bindings to the Moz2D rendering backend.

Great! What is the use case for Moz2D? Why would one use it rather than the other existing Pharo libraries/wrappers?

----- Cheers, Sean -- View this message in context: http://forum.world.st/ANN- Sparta-v1-0-tp4914154p4914184.html Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com.