Hi Keerthivasan, Answers below.
Em ter., 26 de dez. de 2023 às 15:32, Keerthivasan Raghavan < mail2akas...@gmail.com> escreveu: > Hi All, > > I am a newbie to the desktop/embedded linux graphics and widget toolkit. > > The following is a list of questions about how OpenJFX is > architected/designed/implemented: > > * How does openjfx manage the lifecycle of > windows/surfaces/graphics-context(EGL/OpenGL) to draw into? > What is the (design and implementation)/architecture of the window system > abstraction used by OpenJFX? > Any links to code snippets inside OpenJFX showing the > creation/management of an X11-Window/Wayland-Surface would help. > References: > * GTK uses GDK(https://docs.gtk.org/gtk4/drawing-model.html) for managing > windowing abstraction. > * GLFW, a cross platform (window + graphics context + input) management: > https://www.glfw.org/ > * Microsoft Windows win32 API: > https://learn.microsoft.com/en-us/windows/win32/learnwin32/creating-a-window, > > > https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-createwindowexa > > Each platform has its implementation.The abstraction layer is called "glass". In the case of linux, gtk is used. Pure wayland (without XWayland) is not supported yet - and, from my experience, gtk will probably not be used. Look for glass_window.cpp for the Gtk backend. > * How are frames created using drawing operations? > What is the abstraction used to express the content of the frame? > Any code/design links please. > References: > * GTK uses GSK(https://docs.gtk.org/gsk4/) for building the scene graph > that can be rendered as a frame. > * Windows reference: > https://learn.microsoft.com/en-us/windows/win32/learnwin32/your-first-direct2d-program > > The rendering abstraction layer is called "prism". I'm not sure how the scene graph is translated into rendering artifacts. On Linux, GLX is used to glue to OpenGL on a sublayer of prism called "es2". If Wayland is implemented, it will have to use EGL. Windows uses direct3d Mac will use Metal (I think it's under development). > > * How is event management done in OpenGFX ? > Any code/design links please. > Reference: > * GTK uses an main eventloop https://docs.gtk.org/glib/main-loop.html . > Desktop events originate from glass and it's platform dependent. Those events are translated into JavaFX event system. In the case of Linux it also uses GTK eventloop. > > * How are widgets drawn ? How are events dispatched to widgets and how do > widgets react to events ? > How is the application widget UI state stored and what is the > corresponding memory management for storing the UI/widget state ? > Does the UI state get modeled as a scene graph ? > Any code/design links please. > Reference: > * > https://learn.microsoft.com/en-us/windows/win32/learnwin32/retained-mode-versus-immediate-mode > > Widgets are drawn using the scene graph. I think a Node is the basic element (on the public API). In the case of Linux, javafx draws directly into the window/surface (that is passed by glass). This is the case of hardware accelerated rendering. If software is used, it generates a bitmap buffer that is passed to glass. In the case of linux, cairo is used. > Please feel free to reply with code links, design docs, wikis or articles > of the web. > > Thank you, > Keerthivasan Raghavan >
