2016-11-24 8:12 GMT+01:00 Ronie Salgado <roniesalg@gmail.com>:

I am working on removing most of windowing code from the VM, and in trying to unify the platform specific code of the VM. In the MinimalistHeadless branch of https://github.com/ronsaldo/opensmalltalk-vm I made the following changes:

This is super cool. With Pavel we just tried open oswindow based world from headless image and it work almost perfect. No problems with keyboard and scrolling anymore. And it already provides very good approach for deploying desktop app.   

- Unified standard CMake building scripts for Unixes. I hate autoconf. I want to use them in Windows too.
- Refactoring the Unix entry points. I am trying to remove a lot of code for simplfying stuff.
- Null window driver for true headless.
- Optional SDL2 based traditional display backend for compatibility reasons, and because the extra Morphic worlds using OSWindow are a bit unstable.

Could you explain more what traditional display backend means? Because I am probably out of domain but want to know more.  

So far I managed to run a standard Pharo 6 image using this custom VM in Linux. Windows and Mac are coming next. Hopefully this is going to fix the problems with duplicated events when using OSWindow in Windows.

I am also planning on making a standard interface for embedding the VM in an application, at least as a static library. With this new building system, this seems to be easy to do.

BTW. When I tried the minimalistic Pharo image, in a completely headless VM, I got the following error:

[ "Ugh .... now this is a biggie - a system that does not support
        any of the display depths at all."
        'Fatal error: This system has no support for any display depth at all.'
    inContext: thisContext.
Smalltalk quitPrimitive    "There is no way to continue from here" ] in DisplayScreen>>findAnyDisplayDepth
DisplayScreen class>>startUp

As a workaround, I am doing the following for ioHasDisplayDepth with the null driver:

sqInt ioHasDisplayDepth(sqInt depth)
    return true;

I guess it is temp solution? Because no DisplayScreen should exist in headless mode.