Siwin

Cross-platform window creation and event handling library.

Can be used as an alternative to GLFW/GLUT/windy

Features

• works with: OpenGL, Vulkan, software rendering
• works on: Linux(X11 and Wayland), Windows
• handles events from: mouse, keyboard
• and also supports: clipboard, offscreen rendering, interactive move/resize, etc.

Examples

simple window

import siwin, vmath

const color = [32'u8, 32, 32, 255]

run newSoftwareRenderingWindow(), WindowEventsHandler(
  onRender: proc(e: RenderEvent) =
    let pixelBuffer = e.window.pixelBuffer
    
    for y in 0..<pixelBuffer.size.y:
      for x in 0..<pixelBuffer.size.x:
        cast[ptr UncheckedArray[array[4, uint8]]](pixelBuffer.pixels)[y * pixelBuffer.size.x + x] = color

    convertPixelsInplace(pixelBuffer.data, pixelBuffer.size, PixelBufferFormat.bgrx_32bit, pixelBuffer.format)
  ,
  onKey: proc(e: KeyEvent) =
    if (not e.pressed) and e.key == Key.escape:
      close e.window
)

OpenGL

import siwin, opengl, vmath

var window = newOpenglWindow(
  title="OpenGL example",
  preferedPlatform = (when defined(linux): x11 else: defaultPreferedPlatform)
  # note: glBegin and other non- OpenGL ES functions don't work on Wayland
  # see tests/t_opengl_es.nim for more complex, wayland-compatible opengl example
)
loadExtensions()  # init opengl

run window, WindowEventsHandler(
  onResize: proc(e: ResizeEvent) =
    glViewport 0, 0, e.size.x.GLsizei, e.size.y.GLsizei
    glMatrixMode GlProjection
    glLoadIdentity()
    glOrtho -30, 30, -30, 30, -30, 30
    glMatrixMode(GlModelView)
  ,
  onRender: proc(e: RenderEvent) =
    glClearColor 0.3, 0.3, 0.3, 0
    glClear GlColorBufferBit or GlDepthBufferBit

    glShadeModel GlSmooth

    glLoadIdentity()
    glTranslatef -15, -15, 0

    glBegin GlTriangles
    glColor3f 1, 0, 0
    glVertex2f 0, 0
    glColor3f 0, 1, 0
    glVertex2f 30, 0
    glColor3f 0, 0, 1
    glVertex2f 0, 30
    glEnd()
)

note: call redraw(window) every time you want window.render to be called. siwin will automatically call window.render only when window resizes.
note: opengl 1.x and 2.x functions (like glBegin), is not supported on Wayland, due to Wayland only beeng able to initialize with EGL

Vulkan

see t_vulkan.nim

import siwin, nimgl/vulkan, sequtils

doassert vkInit()

let exts = getRequiredVulkanExtensions()
var cexts = exts.mapit(it[0].addr)

var appInfo = newVkApplicationInfo(
  pApplicationName = "siwin Vulkan example",
  applicationVersion = vkMakeVersion(1, 0, 0),
  pEngineName = "No Engine",
  engineVersion = vkMakeVersion(1, 0, 0),
  apiVersion = vkApiVersion1_1
)

var instanceCreateInfo = newVkInstanceCreateInfo(
  pApplicationInfo = appInfo.addr,
  enabledExtensionCount = exts.len,
  ppEnabledExtensionNames = cast[cstringArray](cexts[0].addr),
  enabledLayerCount = 0,
  ppEnabledLayerNames = nil,
)

var instance: VkInstance
doassert vkCreateInstance(instanceCreateInfo.addr, nil, result.addr) == VKSuccess

let window = newVulkanWindow(cast[pointer](instance), title="Vulkan example")
let surface = cast[VkSurfaceKHR](window.vulkanSurface)

# do other initialization using instance and surface...

run window, WindowEventsHandler(
  onRender: proc(e: RenderEvent) =
    ## do rendering...
  ,
  onClose: proc(e: CloseEvent) =
    ## uninitialize before surface destruction
)

# surface already destroyed, continue uninitializing...

pixie

note: very slow, but useful if opengl not needed and if window is used to just display one single image

import siwin, pixie

var image: Image

run newSoftwareRenderingWindow(title="pixie example"), WindowEventsHandler(
  onResize: proc(e: ResizeEvent) =
    if e.size.x * e.size.y <= 0: return
    image = newImage(e.size.x, e.size.y)
  ,
  onRender: proc(e: RenderEvent) =
    if e.window.size.x * e.window.size.y <= 0: return
    image.fill(rgba(255, 255, 255, 255))

    let ctx = image.newContext
    ctx.fillStyle = rgba(0, 255, 0, 255)

    let
      wh = vec2(250, 250)
      pos = vec2(image.width.float, image.height.float) / 2 - wh / 2
    
    ctx.fillRoundedRect(rect(pos, wh), 25.0)

    let pixelBuffer = e.window.pixelBuffer
    copyMem(pixelBuffer.data, image.data[0].addr, pixelBuffer.size.x * pixelBuffer.size.y * Color32bit.sizeof)
    convertPixelsInplace(pixelBuffer.data, pixelBuffer.size, PixelBufferFormat.rgbx_32bit, pixelBuffer.format)
  ,
  onKey: proc(e: KeyEvent) =
    if (not e.pressed) and e.key == Key.escape:
      close e.window
)

clipboard

import siwin

let clipboard = clipboard()

echo clipboard.text
clipboard.text = "some text"

note: on x11 setting cliboard text requires creating window

offscreen rendering

note: this will create invisible window. ctx mustn't be discarded as its destructor will close the window.
If you have multiple contexts, use makeCurrent to select.

import siwin/offscreen, opengl

let ctx {.used.} = newOpenglContext()
loadExtensions()

# do any opengl computing

manual main cycle

import siwin

let window = newOenglWindow()
loadExtensions()

let eventsHandler = WindowEventsHandler(
  # ...
)

window.firstStep(eventsHandler, makeVisible=true)
while window.opened:
  window.step(eventsHandler)

running multiple windows

import siwin

let win1 = newOpenglWindow()
let win2 = newOpenglWindow()
loadExtensions()

let win1_eventsHandler = WindowEventsHandler(
  onResize: proc(e: ResizeEvent) =
    makeCurrent e.window
    #...
  ,
  onRender: proc(e: RenderEvent) =
    makeCurrent e.window
    #...
)
let win2_eventsHandler = WindowEventsHandler(
  onResize: proc(e: ResizeEvent) =
    makeCurrent e.window
    #...
  ,
  onRender: proc(e: RenderEvent) =
    makeCurrent e.window
    #...
)

runMultiple(
  (window: win1, eventsHandler: win1_eventsHandler, makeVisible: true),
  (window: win2, eventsHandler: win2_eventsHandler, makeVisible: true),
)

client-side decorations

import siwin

let window = newOpenglWindow(transparent=true, frameless=true)
loadExtensions()

run window, WindowEventsHandler(
  onMouseMove: proc(e: MouseMoveEvent) =
    if MouseButton.left in e.window.mouse.pressed:
      window.startInteractiveMove()
      # see also: startInteractiveResize
)

all methods and events

see siwin/platforms/any/window

I want to get system handle of window and do some magic, but it is private?

import std/importutils
import siwin/platforms/x11/window
privateAccess WindowX11Obj
# ...
window.handle

Contributions

If you want to support this project, here is some tasks to do:

• See issues
• Any bugfixes is always accepted, just describe somewhere what you fixed
• Refactoring (my code is bad, i know it)
  • if you doing very big refactoring, first create issue to ask is all your changes needed, and if it is, refactor
• Documentation
• Optimization
• MacOS support
• Android/IOS support
• Web support
• copy/paste images
• Make cool site that adverts siwin

Just fork levovix0/siwin to your account, make changes and submit a pull request.
Or if it requires new repository to be created, create it and add an "change dependency" issue.