Setting (toplevel) window coordinates (relative to the screen) is not available on Wayland.
Setting window pos often used to let user move window when it is client-side decorated, and this behavior is available on Wayland.
So add function to start interactive window moving and remove or mark as not cross-platform pos=

It would be really cool if Windy was modular so you only imported the things you really use.

import windy/clipboard

I just discovered windy and it looks like a promising library.
And I'd really like to use windy instead of GLFW for ImGui but I haven't got it working.

import nimgl/[opengl, glfw]
import nimgl/imgui, nimgl/imgui/[impl_opengl, impl_glfw]

proc main() =
  doAssert glfwInit()

  glfwWindowHint(GLFWContextVersionMajor, 3)
  glfwWindowHint(GLFWContextVersionMinor, 3)
  glfwWindowHint(GLFWOpenglForwardCompat, GLFW_TRUE)
  glfwWindowHint(GLFWOpenglProfile, GLFW_OPENGL_CORE_PROFILE)
  glfwWindowHint(GLFWResizable, GLFW_TRUE)

  var win: GLFWWindow = glfwCreateWindow(600, 400, "Example")
  if win == nil:
    quit(-1)

  win.makeContextCurrent()

  doAssert glInit()

  let context = igCreateContext()
  #let io = igGetIO()

  doAssert igGlfwInitForOpenGL(win, true)
  doAssert igOpenGL3Init()

  igStyleColorsCherry()

  var somefloat: float32 = 0.0f
  var counter: int32 = 0

  while not win.windowShouldClose:
    glfwPollEvents()

    igOpenGL3NewFrame()
    igGlfwNewFrame()
    igNewFrame()

    # Simple window
    igBegin("Hello, world!")

    igText("This is some useful text.")

    igSliderFloat("float", somefloat.addr, 0.0f, 1.0f)

    if igButton("Button", ImVec2(x: 0, y: 0)):
      counter.inc
    igSameLine()
    igText("counter = %d", counter)

    igText("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / igGetIO().framerate, igGetIO().framerate)
    igEnd()
    # End simple window

    igRender()

    glClearColor(0.45f, 0.55f, 0.60f, 1.00f)
    glClear(GL_COLOR_BUFFER_BIT)

    igOpenGL3RenderDrawData(igGetDrawData())

    win.swapBuffers()

  igOpenGL3Shutdown()
  igGlfwShutdown()
  context.igDestroyContext()

  win.destroyWindow()
  glfwTerminate()

when isMainModule:
  main()

I really like windy's support of keyboard/mouse, but for making a game-engine I want to support gamepads, primarily.

I made a light wrapper for libstem_gamepad, which is made in C, and works on Windows, Linux, and OSX. I could make it feel a bit more like windy's state-helpers (like buttonPressed / buttonDown / buttonReleased / buttonToggle) and make a PR to include this, if there is interest. Is there a more nim-ish way to do this? Is this outside the scope of what windy is trying to do?

Usage currently looks like this:

let windowSize = ivec2(320, 240)
let window = newWindow("null0", windowSize)
makeContextCurrent(window)
loadExtensions()

proc onGamepadAttached(device: ptr Gamepad_device; context: pointer) =
  var js = device[]
  echo "attached: " & $js.deviceID

proc onGamepadRemoved(device: ptr Gamepad_device; context: pointer) =
  var js = device[]
  echo "removed: " & $js.deviceID

proc onButtonDown (device: ptr Gamepad_device; buttonID: cuint; timestamp: cdouble; context: pointer) =
  var js = device[]
  echo "buttonDown(" & $js.deviceID & "): " & $buttonID

proc onButtonUp (device: ptr Gamepad_device; buttonID: cuint; timestamp: cdouble; context: pointer) =
  var js = device[]
  echo "buttonUp(" & $js.deviceID & "): " & $buttonID

proc onAxisMoved (device: ptr Gamepad_device; axisID: cuint; value: cfloat; lastValue: cfloat; timestamp: cdouble; context: pointer) =
  var js = device[]
  echo "axis(" & $js.deviceID & "): " & $axisID & " : " & $value

const GAMEPAD_POLL_ITERATION_INTERVAL=30
gamepad.deviceAttachFunc(onGamepadAttached)
gamepad.deviceRemoveFunc(onGamepadRemoved)
gamepad.buttonDownFunc(onButtonDown)
gamepad.buttonUpFunc(onButtonUp)
gamepad.axisMoveFunc(onAxisMoved)
gamepad.init()

var iterationsToNextPoll = GAMEPAD_POLL_ITERATION_INTERVAL
while not window.closeRequested:
  pollEvents()
  dec iterationsToNextPoll
  if iterationsToNextPoll == 0:
    gamepad.detectDevices()
    iterationsToNextPoll = GAMEPAD_POLL_ITERATION_INTERVAL
  gamepad.processEvents()

Hi,

I'm just curious why does Windy provide HTTP functionality?

It seems that Windy is about making and managing windows on different
platforms and HTTP seems like different topic. Is there a reason
why does Windy also include HTTP support?

.nimble\pkgs\windy-0.0.0\windy\platforms\win32\platform.nim(872, 17) Error: cannot convert 513 to range 0..255(int)

Works fine with ver. 1.6.10

I want to render text file, encounter this error, I don't know how to set the text pos, with translate(vec2(100, 100)) I get this error.

import std/[os]
import boxy, opengl, windy

const ProjectDir = currentSourcePath.parentDir
let window = newWindow("textee", ivec2(1280, 800))
window.size = (window.size.vec2 * window.contentScale).ivec2

makeContextCurrent(window)

loadExtensions()

let bxy = newBoxy()

var frame: int

let typeface = readTypeface( ProjectDir / "assets/DejaVuSansMono.ttf")
# let source = readFile(currentSourcePath)

proc drawText(
  bxy: Boxy,
  imageKey: string,
  transform: Mat3,
  typeface: Typeface,
  text: string,
  size: float32,
  color: Color
) =
  var font = newFont(typeface)
  font.size = size
  font.paint = color
  let
    arrangement = typeset(@[newSpan(text, font)], bounds = vec2(1280, 800))
    globalBounds = arrangement.computeBounds(transform).snapToPixels()
  echo globalBounds
  let
    textImage = newImage(globalBounds.w.int, globalBounds.h.int)
    imageSpace = translate(-globalBounds.xy) * transform
  textImage.fillText(arrangement, imageSpace)

  bxy.addImage(imageKey, textImage)
  bxy.drawImage(imageKey, globalBounds.xy)

const BackgroundColor = color(1, 1, 1, 1)
const TextColor = color(0, 0, 0)
const FontSize = 28
# Called when it is time to draw a new frame.
window.onFrame = proc() =
  # Clear the screen and begin a new frame.
  bxy.beginFrame(window.size)

  bxy.drawRect(rect(vec2(0, 0), window.size.vec2), BackgroundColor)
  var i = 0
  for line in currentSourcePath.lines:
    bxy.drawText(
      $i,
      translate(vec2(100, 100)),
      typeface,
      line,
      FontSize,
      TextColor
    )
    inc i

  # End this frame, flushing the draw commands.
  bxy.endFrame()
  # Swap buffers displaying the new Boxy frame.
  window.swapBuffers()
  inc frame

while not window.closeRequested:
  pollEvents()

Hi,

I've been hacking away on the wayland backend part of windy. I'm working on adding support for hardware graphics buffers as well as supporting some of the wayland protocol extensions used in modern wayland desktops, like:

• https://wayland.app/protocols/xdg-shell
  Standard shell surface (window) management

• https://wayland.app/protocols/idle-inhibit-unstable-v1
  Apps can tell the compositor not go to sleep/dpms if they are "active". This is basically "prevent screensaver" for wayland.
  It's needed for apps/games using input methods not handled by the compositor's idle system.
  This can even be regular gamepads if the compositor doesn't let the inputs of such a device "reset the idle timer"

• https://wayland.app/protocols/linux-dmabuf-unstable-v1
  Use graphics buffers coming from anywhere, e.g. from a camera, but in general it brings much flexibility to the table.
  Also needed or very useful for certain embedded systems (and accursed (nvidia) drivers).
  Also useful in order to do single-buffering on wayland, if one wants that.

• https://wayland.app/protocols/presentation-time
  Needed for video/audio synchronization

• https://wayland.app/protocols/wlr-layer-shell-unstable-v1
  So windy can be used to build bars/menus/launchers for wayland based desktops 😀

Are you open for contributions/PRs/discussions? :)

/.nimble/bin/nim c --usenimcache --nimcache=/.cache/nim/jb_windy/triangle.nim_d /windy/examples/triangle.nim
Hint: used config file '/.choosenim/toolchains/nim-1.6.12/config/nim.cfg' [Conf]
Hint: used config file '/.choosenim/toolchains/nim-1.6.12/config/config.nims' [Conf]
.......................................................................................................................................................................................................................
/.nimble/pkgs/windy-0.0.0/windy/http.nim(68, 3) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(79, 5) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(82, 54) template/generic instantiation of async from here
/.nimble/pkgs/windy-0.0.0/windy/http.nim(91, 70) template/generic instantiation of async from here
/.nimble/pkgs/windy-0.0.0/windy/http.nim(96, 7) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(82, 54) template/generic instantiation of async from here
/.nimble/pkgs/windy-0.0.0/windy/http.nim(91, 70) template/generic instantiation of async from here
/.choosenim/toolchains/nim-1.6.12/lib/pure/asyncmacro.nim(42, 5) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(82, 54) template/generic instantiation of async from here
/.nimble/pkgs/windy-0.0.0/windy/http.nim(112, 38) template/generic instantiation of request from here
/.choosenim/toolchains/nim-1.6.12/lib/pure/httpclient.nim(1086, 14) Warning: Deprecated since v1.5; use HttpMethod enum instead; string parameter httpMethod is deprecated [User]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(82, 54) template/generic instantiation of async from here
/.nimble/pkgs/windy-0.0.0/windy/http.nim(112, 38) template/generic instantiation of request from here
/.choosenim/toolchains/nim-1.6.12/lib/pure/asyncmacro.nim(42, 5) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(82, 54) template/generic instantiation of async from here
/.nimble/pkgs/windy-0.0.0/windy/http.nim(138, 3) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(82, 54) template/generic instantiation of async from here
/.choosenim/toolchains/nim-1.6.12/lib/pure/asyncmacro.nim(42, 5) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(143, 50) template/generic instantiation of async from here
/.nimble/pkgs/windy-0.0.0/windy/http.nim(177, 3) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(143, 50) template/generic instantiation of async from here
/.nimble/pkgs/windy-0.0.0/windy/http.nim(187, 5) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(143, 50) template/generic instantiation of async from here
/.choosenim/toolchains/nim-1.6.12/lib/pure/asyncmacro.nim(42, 5) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(197, 3) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
/.nimble/pkgs/windy-0.0.0/windy/http.nim(204, 3) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
...
/.nimble/pkgs/windy-0.0.0/windy/platforms/macos/objc.nim(156, 14) Hint: 'addProtocol' is declared but not used [XDeclaredButNotUsed]
/.nimble/pkgs/windy-0.0.0/windy/platforms/macos/objc.nim(156, 14) Hint: 'addProtocol' is declared but not used [XDeclaredButNotUsed]
/.nimble/pkgs/windy-0.0.0/windy/platforms/macos/platform.nim(936, 3) template/generic instantiation of autoreleasepool from here
/.nimble/pkgs/windy-0.0.0/windy/platforms/macos/platform.nim(964, 5) Warning: The bare except clause is deprecated; use except CatchableError: instead [BareExcept]
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/std/private/digitsutils.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/system/assertions.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/system/formatfloat.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/system/dollars.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/system/io.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/system.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/pure/bitops.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/pure/math.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/pure/strutils.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/posix/posix.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/pure/dynlib.nim
CC: ../../../../../../../.nimble/pkgs/opengl-1.2.6/opengl.nim
CC: ../../../../../../../.nimble/pkgs/vmath-1.2.0/vmath.nim
CC: ../../../../../../../.nimble/pkgs/chroma-0.2.7/chroma/colortypes.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/pure/collections/tables.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/pure/options.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/pure/times.nim
CC: ../../../../../../../.choosenim/toolchains/nim-1.6.12/lib/pure/os.nim
CC: ../../../../../../../.nimble/pkgs/pixie-5.0.6/pixie/common.nim
CC: ../../../../../../../.nimble/pkgs/nimsimd-1.2.5/nimsimd/runtimecheck.nim
CC: ../../../../../../../.nimble/pkgs/pixie-5.0.6/pixie/simd.nim
CC: ../../../../../../../.nimble/pkgs/pixie-5.0.6/pixie/internal.nim
CC: ../../../../../../../.nimble/pkgs/pixie-5.0.6/pixie/paths.nim
CC: ../../../../../../../.nimble/pkgs/pixie-5.0.6/pixie/fonts.nim
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/common.nim
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/internal.nim
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/bitstreams.nim
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/adler32_simd.nim
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/adler32.nim
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/crc32_simd.nim
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/crc.nim
/.cache/nim/jb_windy/triangle.nim_d/@m..@s..@s..@s..@s..@s..@s..@susers@[email protected]@[email protected]@[email protected]:131:10: error: invalid output constraint '=a' in asm
:"=a"(eaxr), "=b"(ebxr), "=c"(ecxr), "=d"(edxr)
^
1 error generated.
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/lz77.nim
CC: ../../../../../../../.nimble/pkgs/zippy-0.10.7/zippy/snappy.nim
Error: execution of an external compiler program 'clang -c -w -ferror-limit=3 -I~/.choosenim/toolchains/nim-1.6.12/lib -I/windy/examples -o ~/.cache/nim/jb_windy/triangle.nim_d/@m..@s..@s..@s..@s..@s..@s..@susers@[email protected]@[email protected]@[email protected] ~/.cache/nim/jb_windy/triangle.nim_d/@m..@s..@s..@s..@s..@s..@s..@susers@[email protected]@[email protected]@[email protected]' failed with exit code: 1

~/.cache/nim/jb_windy/triangle.nim_d/@m..@s..@s..@s..@s..@s..@s..@susers@[email protected]@[email protected]@[email protected]:826:10: error: invalid output constraint '=a' in asm
:"=a"(eaxr), "=b"(ebxr), "=c"(ecxr), "=d"(edxr)
^
1 error generated.

I tried figure out how to center window, then I found windy position window to left and top default internally, the macOS default behavior is center window.

In src/windy/platforms/x11.nim the Window is missing the onFrame field. Here's a diff of my fix:

--- a/src/windy/platforms/linux/x11.nim
+++ b/src/windy/platforms/linux/x11.nim
@@ -5,6 +5,7 @@ type
 
   Window* = ref object
     onCloseRequest*: Callback
+    onFrame*: Callback
     onMove*: Callback
     onResize*: Callback
     onFocusChange*: Callback
@@ -782,6 +783,8 @@ proc pollEvents(window: Window) =
         window.prevSize = ev.configure.size
         if window.onResize != nil:
           window.onResize()
+        if window.onFrame != nil:
+          window.onFrame()
 
     of xeMotion:
       window.mousePrevPos = window.mousePos

• Win32
• Linux (X11)
• Mac OS

Due to how the context is acquired. See baldurk/renderdoc#809

The problem is in platforms\win32\platform.nim(680)

Possibly with sdl2?

I've seen that there are several nice utilities to compose objc classes and bootstrap delegates in the windy internals for macOS. Is it possible to make a separate library in order to use those in other projects ? I'm currently trying to work with Metal directly from nim and some of those classes / methods would come in handy (and don't want to duplicate them in my project).

Btw suggestion for the name: objetty 😄

Not sure if this exists on other platforms

import opengl, windy

let window = newWindow("Windy Basic", ivec2(1280, 800))

window.makeContextCurrent()
loadExtensions()

var offset = ivec2(0, 0)

proc display() =
  glClear(GL_COLOR_BUFFER_BIT)
  # Your OpenGL display code here
  window.swapBuffers()

while not window.closeRequested:
  display()
  pollEvents()
  if window.buttonDown[MouseLeft]:
    offset += window.mouseDelta
  echo offset

Run this, then click and drag the mouse starting in the upper left corner and move it around for ~20 seconds, when you bring the mouse back to the starting point (while still dragging) the offset will be wrong by a magnitude of about 100

Video demonstration:

I don't understand the logic here - why tightly couple this project with another dependency like vmath? IMO users shouldn't have to buy into your linear algebra library to use your windowing library. This is the same type of issue I have with fidget but even more egregious...

win32\platform.nim(1348, 12) Error: startHttpRequest requires --threads:on option

Not sure if this can be configured per nimble library that it needs this feature to be used?

import opengl, os, windy

when isMainModule:

  let window = newWindow(
    "Windy",
    ivec2(1280, 800),
    openglMajorVersion = 2,
    openglMinorVersion = 0,
  )

  window.makeContextCurrent()
  loadExtensions()

  echo "GL_VERSION: ", cast[cstring](glGetString(GL_VERSION))
  echo "GL_VENDOR: ", cast[cstring](glGetString(GL_VENDOR))
  echo "GL_RENDERER: ", cast[cstring](glGetString(GL_RENDERER))

  while not window.closeRequested:
    pollEvents()
    sleep(10)

Error:

C:\Users\Cameron\Documents\Authored\nimzoom\src\nimzoom.nim(5) nimzoom
C:\Users\Cameron\.nimble\pkgs\windy-0.0.0\windy\platforms\win32\platform.nim(895) newWindow
[[reraised from:
C:\Users\Cameron\Documents\Authored\nimzoom\src\nimzoom.nim(5) nimzoom
C:\Users\Cameron\.nimble\pkgs\windy-0.0.0\windy\platforms\win32\platform.nim(911) newWindow
]]
Error: unhandled exception: Error creating OpenGL context [WindyError]

Almost all other example compile and run perfectly except examples/triangle.nim. which produce this error at runtime.

sk@sk-pc:~/myfolder/nim/windy/examples$ ./triangle 
0:1(10): error: GLSL 4.10 is not supported. Supported versions are: 1.10, 1.20, 1.30, 1.00 ES, 3.00 ES, and 3.10 ES

0:1(10): error: GLSL 4.10 is not supported. Supported versions are: 1.10, 1.20, 1.30, 1.00 ES, 3.00 ES, and 3.10 ES

error: linking with uncompiled/unspecialized shadererror: linking with uncompiled/unspecialized shader
/home/sk/myfolder/nim/windy/examples/triangle.nim(104) triangle
/home/sk/myfolder/nim/windy/examples/triangle.nim(96) display
/home/sk/.nimble/pkgs/opengl-1.2.6/opengl/private/errors.nim(44) glUseProgram
/home/sk/.nimble/pkgs/opengl-1.2.6/opengl/private/errors.nim(99) checkGLerror
Error: unhandled exception: OpenGL error: invalid operation [GLerror]

Other Information

Nim version: 1.6.6 [amd64]
OS: Linux Mint 20.3
To test if there is anything wrong with OpenGL driver, I run some demo code with

• NimGL, runs without any issue.
• PyOpenGL, runs without any Issue.

Compile error:

nimble build -d:mingw
/home/username/.nimble/pkgs2/windy-0.0.0-e0506a1d00e0daf1ffa44f00959853bbae29b01f/windy/platforms/win32/platform.nim(872, 17) Error: cannot convert 513 to range 0..255(int)

Nim version:

Nim Compiler Version 1.9.3 [Linux: amd64]
Compiled at 2023-04-19                                                                                                                                                                        Copyright (c) 2006-2023 by Andreas Rumpf                                                                                                                                                                                                                                                                                                                                                    git hash: 24b6378382f4bcde3b354f0a8137604192c7570f
active boot switches: -d:release

windy version:
windy [(version: 0.0.0, checksum: e0506a1d00e0daf1ffa44f00959853bbae29b01f)]

I see windy use a lot in function declaration as argument. it's CT error in nim devel

nim version: Nim Compiler Version 1.9.5 [MacOSX: amd64]

I thought I had this working, but started getting this on new projects:

Users/konsumer/.cache/nim/null0_d/@m..@s..@[email protected]@[email protected]@swindy@splatforms@[email protected]:820:10: error: incompatible function pointer types assigning to 'tyProc__ELDcQK9cgdUyzj5KMs6i3sA' (aka 'long long (*)(long long, long long)') from 'tyProc__ln4kdL5W9bbX4a1xl8nnVXQ' (aka 'void (*)(void)') [-Wincompatible-function-pointer-types]
        msgSend = Dl_3472883728_;
                ^ ~~~~~~~~~~~~~~

Here is my simple demo code:

import opengl, windy

let window = newWindow("Windy Basic", ivec2(1280, 800))

window.makeContextCurrent()
loadExtensions()

proc display() =
  glClear(GL_COLOR_BUFFER_BIT)
  # Your OpenGL display code here
  window.swapBuffers()

while not window.closeRequested:
  display()
  pollEvents()

OS: MacOSX Ventura 13.3.1 (22E261)
Arch: x86_64
Nim: 1.6.12

requires "opengl >= 1.2.6"
requires "windy >= 0.0.0"
requires "boxy >= 0.4.1"

From this program:

import opengl, windy

let window = newWindow("Windy Basic", ivec2(1280, 800))

window.makeContextCurrent()
loadExtensions()

proc display() =
  glClear(GL_COLOR_BUFFER_BIT)
  # Your OpenGL display code here
  window.swapBuffers()

while not window.closeRequested:
  display()
  pollEvents()
  echo window.mousePrevPos