History

Noel Grandin 08f757c32f clang-tidy modernize-pass-by-value in canvas Change-Id: Ib6e1b6182d83b09dbf5e2aeb9cf3e4ca11d9f48b Reviewed-on: https://gerrit.libreoffice.org/c/core/+/134712 Tested-by: Jenkins Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>		2022-05-21 21:55:31 +02:00
..
inc	clang-tidy modernize-pass-by-value in canvas	2022-05-21 21:55:31 +02:00
opengl
qa/cppunit	Recheck modules [a-c]* with IWYU	2022-01-13 08:26:15 +01:00
source	clang-tidy modernize-pass-by-value in canvas	2022-05-21 21:55:31 +02:00
workben	clang-tidy modernize-pass-by-value in canvas	2022-05-21 21:55:31 +02:00
CppunitTest_canvas_test.mk	make it possible to write canvas unittests	2021-05-06 11:22:47 +02:00
Executable_canvasdemo.mk	Drop support for OpenGL denylist on X11	2022-03-28 14:31:07 +02:00
IwyuFilter_canvas.yaml	Recheck modules [a-c]* with IWYU	2022-01-13 08:26:15 +01:00
Library_cairocanvas.mk	Generally determine Rdb content from gb_*_set_componentfile calls	2021-12-10 08:14:24 +01:00
Library_canvasfactory.mk	Generally determine Rdb content from gb_*_set_componentfile calls	2021-12-10 08:14:24 +01:00
Library_canvastools.mk	add PCHs for canvas/	2020-10-02 20:39:36 +02:00
Library_directx9canvas.mk	Generally determine Rdb content from gb_*_set_componentfile calls	2021-12-10 08:14:24 +01:00
Library_gdipluscanvas.mk	Generally determine Rdb content from gb_*_set_componentfile calls	2021-12-10 08:14:24 +01:00
Library_oglcanvas.mk	Generally determine Rdb content from gb_*_set_componentfile calls	2021-12-10 08:14:24 +01:00
Library_simplecanvas.mk	Generally determine Rdb content from gb_*_set_componentfile calls	2021-12-10 08:14:24 +01:00
Library_vclcanvas.mk	Generally determine Rdb content from gb_*_set_componentfile calls	2021-12-10 08:14:24 +01:00
Makefile
Module_canvas.mk	gbuild: build static LO / link static executables	2022-01-12 11:12:46 +01:00
Package_opengl.mk
README.md	Updated README.md files to represent current code / use Markdown format	2021-04-07 17:47:16 +02:00
README.vars
StaticLibrary_directxcanvas.mk	messing with UNOMINMAX no longer seems to be necessary	2021-05-04 20:02:28 +02:00

README.md

UNO-based Graphics Backend

UNO-based graphics backend, lesser impedance to modern graphics APIs than vcl.

The canvas Framework

The canvas framework is the successor of the system GUI and graphics backend VCL. Basic functionality is available, supplying just as much features as necessary to provide a VCL-equivalent feature set (except proper BiDi/CTL support).

The canvas framework consists of the following two modules, canvas and cppcanvas. Additionally, a new generic graphics tooling is used (but not exclusively by the canvas, Armin's drawinglayer module also make use of it), which resides in basegfx.

The UNO API used by the canvas is primarily under css::rendering, with css::rendering::XCanvas being the central interface.

The slideshow Engine

The slideshow engine has replaced the former Impress-embedded presentation framework with a fully independent UNO component, and it is based on the canvas. Some features used there are only available from canvas, like double-buffering, and hardware-accelerated alpha-blending (currently not on all platforms).

Cairo canvas

Cairo canvas is one of backends of canvas component. canvas is mostly used for slideshow rendering and also for emf+ rendering. we hoped it will even be used by drawing layer, but it didn't happen (yet?) for API look at offapi/com/sun/star/rendering/, the implementation is in canvas and cppcanvas modules.

Cairo canvas backend uses Cairo library for rendering. Main advantage is support of alpha transparency and in some cases accelerated rendering.

The backend itself is quite old and stable, not many changes in that area lately, mostly changes for emf+ rendering, communication with vcl and bugfixes

Future Works

Look at Cairo canvas and situation when it is used (mostly slideshow).

TODO

There still might be more cases when we can save some roundtrips when exchanging data with vcl.