Huge progress

- Move context to an explicit gl_context module
- Move surface context to a dedicated swapchain abstraction
- Allow headless creation of OpenGL contexts, this is what will be used
  by default when creating buffers and stuff like that in devices when
  no surface/swapchain is present, and new created contexts will inherit
  from this context.

Next thing to be done is a render pass needs to be created which
explicitly sets the vertex/index buffers and creates the VAO for you
internally (and caches it).

Because I currently cant use this headless mode without it breaking
stuff due to the vao not being shared.

Author: codebycruz

packages/arisu-app/plugin/render.lua

@@ -13,15 +13,15 @@ local Instance = require("arisu-gfx.instance")
 
 ---@class arisu.plugin.Render.Context
 ---@field window winit.Window
----@field surface gfx.gl.Surface
+---@field swapchain gfx.gl.Swapchain
 ---@field quadVAO VAO
 ---@field quadPipeline Pipeline
----@field quadVertex gfx.Buffer
----@field quadIndex gfx.Buffer
+---@field quadVertex gfx.gl.Buffer
+---@field quadIndex gfx.gl.Buffer
 ---@field overlayVAO VAO
 ---@field overlayPipeline Pipeline
----@field overlayVertex gfx.Buffer
----@field overlayIndex gfx.Buffer
+---@field overlayVertex gfx.gl.Buffer
+---@field overlayIndex gfx.gl.Buffer
 ---@field ui? arisu.Element
 ---@field layoutTree? arisu.Layout
 ---@field computedLayout? arisu.ComputedLayout
@@ -70,7 +70,8 @@ function RenderPlugin:register(window)
 	local ctx = self.windowPlugin:getContext(window)
 	assert(ctx, "Window context not found for render plugin")
 
-	ctx.surface.context:makeCurrent()
+	local swapchain = ctx.surface:configure(self.device, {}) --[[@as gfx.gl.Swapchain]]
+	swapchain.ctx:makeCurrent()
 
 	local vertexDescriptor = VertexLayout.new()
 		:withAttribute({ type = "f32", size = 3, offset = 0 }) -- position (vec3)
@@ -139,7 +140,7 @@ function RenderPlugin:register(window)
 	---@type arisu.plugin.Render.Context
 	local ctx = {
 		window = window,
-		surface = ctx.surface,
+		swapchain = swapchain,
 		quadVAO = quadVAO,
 		quadPipeline = quadPipeline,
 		quadVertex = quadVertex,
@@ -162,7 +163,7 @@ end
 
 ---@param ctx arisu.plugin.Render.Context
 function RenderPlugin:draw(ctx)
-	ctx.surface.context:makeCurrent()
+	ctx.swapchain.ctx:makeCurrent()
 
 	gl.enable(gl.BLEND)
 	gl.blendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
@@ -184,7 +185,7 @@ end
 function RenderPlugin:event(event, handler)
 	if event.name == "resize" then
 		local ctx = self:getContext(event.window)
-		ctx.surface.context:makeCurrent()
+		ctx.swapchain.ctx:makeCurrent()
 		gl.viewport(0, 0, ctx.window.width, ctx.window.height)
 
 		if util.isWindows() then

packages/arisu-app/plugin/window.lua

@@ -2,7 +2,7 @@ local Surface = require("arisu-gfx.surface")
 
 ---@class arisu.plugin.Window.Context
 ---@field window winit.Window
----@field surface gfx.gl.Surface
+---@field surface gfx.Surface
 
 ---@class arisu.plugin.Window<Message>: { onWindowCreate: Message }
 ---@field mainCtx arisu.plugin.Window.Context?

packages/arisu-gfx/device/gl.lua

@@ -1,16 +1,21 @@
 local GLBuffer = require("arisu-gfx.buffer.gl")
 local GLEncoder = require("arisu-gfx.encoder.gl")
+local GLContext = require("arisu-gfx.gl_context")
 
 ---@class gfx.gl.Device
+---@field globalContext gfx.gl.Context
 local GLDevice = {}
 GLDevice.__index = GLDevice
 
 function GLDevice.new()
-	return setmetatable({}, GLDevice)
+	local context = GLContext.fromHeadless()
+	return setmetatable({ globalContext = context }, GLDevice)
 end
 
 ---@param descriptor gfx.BufferDescriptor
 function GLDevice:createBuffer(descriptor)
+	-- todo: enable this when vaos dont exist
+	-- self.globalContext:makeCurrent()
 	return GLBuffer.new(descriptor)
 end
 

packages/arisu-gfx/gl_context.lua

@@ -0,0 +1,13 @@
+local util = require("arisu-util")
+
+---@class gfx.gl.Context
+---@field fromHeadless fun(sharedCtx: gfx.gl.Context?): gfx.gl.Context
+---@field fromWindow fun(window: winit.Window, sharedCtx: gfx.gl.Context?): gfx.gl.Context
+---@field makeCurrent fun(self: gfx.gl.Context): boolean
+---@field swapBuffers fun(self: gfx.gl.Context)
+---@field destroy fun(self: gfx.gl.Context)
+local Context = util.isWindows()
+	and require("arisu-gfx.gl_context.win32")
+	or require("arisu-gfx.gl_context.x11") --[[@as gfx.gl.Context]]
+
+return Context

packages/arisu-gfx/surface/gl/win32.lua packages/arisu-gfx/gl_context/win32.luapackages/arisu-gfx/surface/gl/win32.lua renamed to packages/arisu-gfx/gl_context/win32.lua

@@ -11,7 +11,7 @@ Win32Context.__index = Win32Context
 
 ---@param window winit.win32.Window
 ---@param sharedCtx Win32Context?
-function Win32Context.new(window, sharedCtx)
+function Win32Context.fromWindow(window, sharedCtx)
 	local hdc = user32.getDC(window.hwnd)
 
 	local pfDescriptor = gdi.newPFD()

packages/arisu-gfx/surface/gl/x11.lua packages/arisu-gfx/gl_context/x11.luapackages/arisu-gfx/surface/gl/x11.lua renamed to packages/arisu-gfx/gl_context/x11.lua

@@ -1,6 +1,5 @@
 local glx = require("arisu-x11.glx")
 local x11 = require("arisu-x11.x11")
-local gl = require("arisu-opengl")
 
 --- @class X11Context
 --- @field display XDisplay
@@ -9,10 +8,10 @@ local gl = require("arisu-opengl")
 local X11Context = {}
 X11Context.__index = X11Context
 
----@param window winit.x11.Window
+---@param display XDisplay
 ---@param sharedCtx X11Context?
-function X11Context.new(window, sharedCtx)
-	local display = window.display
+---@param window winit.x11.Window?
+function X11Context.new(display, sharedCtx, window)
 	local screen = x11.defaultScreen(display)
 
 	local fbConfig = glx.chooseFBConfig(display, screen, {
@@ -42,13 +41,31 @@ function X11Context.new(window, sharedCtx)
 	return setmetatable({ ctx = ctx, display = display, window = window }, X11Context)
 end
 
+---@param sharedCtx X11Context?
+function X11Context.fromHeadless(sharedCtx)
+	local display = x11.openDisplay(nil)
+	return X11Context.new(display, sharedCtx)
+end
+
+---@param window winit.x11.Window
+---@param sharedCtx X11Context?
+function X11Context.fromWindow(window, sharedCtx)
+	return X11Context.new(window.display, sharedCtx, window)
+end
+
 ---@return boolean # true on success, false on failure
 function X11Context:makeCurrent()
-	return glx.makeCurrent(self.display, self.window.id, self.ctx) ~= 0
+	if self.window then
+		return glx.makeCurrent(self.display, self.window.id, self.ctx) ~= 0
+	end
+
+	return glx.makeContextCurrent(self.display, 0, 0, self.ctx) ~= 0
 end
 
 function X11Context:swapBuffers()
-	glx.swapBuffers(self.display, self.window.id)
+	if self.window then
+		glx.swapBuffers(self.display, self.window.id)
+	end
 end
 
 function X11Context:destroy()

packages/arisu-gfx/surface.lua

@@ -1,5 +1,8 @@
+---@class gfx.SurfaceConfig
+
 ---@class gfx.Surface
 ---@field new fun(window: winit.Window): gfx.Surface
+---@field configure fun(self: gfx.Surface, device: gfx.Device, config: gfx.SurfaceConfig): gfx.Swapchain
 local Surface = require("arisu-gfx.surface.gl") --[[@as gfx.Surface]]
 
 return Surface

packages/arisu-gfx/surface/gl.lua

@@ -1,23 +1,23 @@
 local util = require("arisu-util")
 
+local GLContext = require("arisu-gfx.gl_context")
+local GLSwapchain = require("arisu-gfx.swapchain.gl")
+
 ---@class gfx.gl.Surface
----@field context gfx.Context
+---@field window winit.Window
 local GLSurface = {}
 GLSurface.__index = GLSurface
 
----@class gfx.Context
----@field new fun(window: winit.Window, sharedCtx: gfx.Context?): gfx.Context
----@field makeCurrent fun(self: gfx.Context): boolean
----@field swapBuffers fun(self: gfx.Context)
----@field destroy fun(self: gfx.Context)
-local Context = util.isWindows()
-	and require("arisu-gfx.surface.gl.win32")
-	or require("arisu-gfx.surface.gl.x11") --[[@as gfx.Context]]
-
 ---@param window winit.win32.Window
 function GLSurface.new(window)
-	local context = Context.new(window, nil)
-	return setmetatable({ context = context, window = window }, GLSurface)
+	return setmetatable({ window = window }, GLSurface)
+end
+
+---@param device gfx.gl.Device
+---@param config gfx.SurfaceConfig
+function GLSurface:configure(device, config)
+	local context = GLContext.fromWindow(self.window, device.globalContext)
+	return GLSwapchain.new(context)
 end
 
 return GLSurface

packages/arisu-gfx/swapchain.lua

@@ -0,0 +1,5 @@
+---@class gfx.Swapchain
+---@field present fun(self: gfx.Swapchain)
+local Swapchain = require("arisu-gfx.swapchain.gl") --[[@as gfx.Swapchain]]
+
+return Swapchain

packages/arisu-gfx/swapchain/gl.lua

@@ -0,0 +1,16 @@
+local gl = require("arisu-opengl")
+
+---@class gfx.gl.Swapchain
+---@field ctx gfx.gl.Context
+local GLSwapchain = {}
+
+---@param ctx gfx.gl.Context
+function GLSwapchain.new(ctx)
+	return setmetatable({ ctx = ctx }, GLSwapchain)
+end
+
+function GLSwapchain:present()
+	self.ctx:swapBuffers()
+end
+
+return GLSwapchain