Get the coordinates of the corners of the viewport

Anton_S

Here is window procedure I'm using to monitor window events: [Window Procedure](https://msdn.microsoft.com/en-us/library/windows/desktop/ms633573(v)
Here is more info about window procedures and how to use them: https://msdn.microsoft.com/en-us/library/windows/desktop/ms632593(v=vs.85).aspx

Anton_S

My observers work by intersecting into SU window procedure and monitoring its messages. That is, too, possible with Windows API. No timers are needed. I have it all integrated in my C++ extension of AMS Library. You can read here about window procedure: https://msdn.microsoft.com/en-us/library/windows/desktop/ms633573(v=vs.85).aspx

dacastror

Anton thank you very much, I'll get to study this

Anton_S

Your welcome, dacastror. Window Procedure is a callback function. Win32API has no feature to create callbacks. You could use Ruby Fiddle (available as standard lib in SU2014+) or Win32-API (A more advanced win32 API by Daniel J Berger), but they could endup very performance consuming if you try to monitor SU WindowProc through Ruby. You might want to consider writing a C/C++ extension.

Hey, I will make a little C++ extension for you as you mentioned your not very familiar with C and how to use it in SU. All you'll need is Visual Studio (VS2010 preferred).

dacastror

Anton you're great, I will be attentive to what you show me to make a extension.

Anton_S

Okay, I finished it!

Extract dacastror.zip into your plugins folder, run SU, and see what happens.

This dacastror extension works under Ruby version 1.8.6 and up, which means it will work in SU8 and up. To make it work in SU6 and SU7, you'll need to update SU Ruby interpreter. Do that by copying msvcrt-ruby18.dll from SU8 or SU2013 path and pasting it in SU6/7 path (overwriting outdated ruby interpreter). Something else can be done with the C++ extension itself, to make it work under SU6/7, but I don't find it necessary as old SU versions are "deprecated" anyway.

The C++ extension works with visual studio (2010 preferred). I omitted several unused mac libraries and removed Swig, from original Github download, and just left the necessary parts. This reduced size significantly. Do the following to compile and use your c++ extension:

Extract SketchUp Ruby C++ Extensions.zip
Run SketchUp Ruby C++ Extensions/SketchUp Ruby C++ Extensions.sln
Select Solution Configurations box to preferred Ruby version, Release (2.0) is there by default.
Select Solution Platforms box to preferred platform, x64 is there by default.
Open Solution Explorer, right-click on dacastror project, and select Build.
Navigate to SketchUp Ruby C++ Extensions/Release x.y/... and get your .so library from there.
For you plugin, you will need 3 builds: Release 1.8 Win32, Release 2.0 Win32, and Release 2.0 x64.
Copy/Move dacastror.so to it desired folder in Plugins/dacastror/win[32/64]/[1.8/2.0]/

Your dacastror plugin already has all compiled so libraries. I added this as a guide so you could use it whenever you want to modify your C++ extension.

Oh and by the way, your dacastror.so contains the following functions:
`

Dacastror::Windows.get_main_handle
Dacastror::Windows.get_viewport_handle
Dacastror::Windows.get_viewport_rect
Dacastror::Windows.add_observer(object)
Dacastror::Windows.remove_observer(object)`
See Plugins/dacastror/main.rb for more info.
You can also generate documentation of your C++ extension. Read more about it in SketchUp Ruby C++ Extensions/Dacastror/src/How To Generate Doc.txt

Dacastror sample plugin. Place in plugins folder.

Dacastror C++ extension. You'll need visual studio to use it.

dacastror

Anton thank you very much, this is great, Christmas had never come so early for me, I am very happy. I am examining every part of this and I'm downloading "visual studio 2010," I'm trying to absorb all this.

dacastror

I just installed extesion and open sketchup, works great !!
these observers are perfectly suited to my need

Anton_S

Gurait! That c++ extension you have is my latest masterpiece. I'm pretty sure I'll have to improve my old AMS Library .

dacastror

where you learn to do these wonderful things?

Anton_S

By examining other extensions and stuff I learned how to use C++. Now, I take CS162 at college and C++ becomes an easy language to use. My knowledge of Windows API is all from my long experience using it. It took some effort developing useful methods and optimizing them over time. It was all worth it though .

tt_su

@anton_s said:

By examining other extensions and stuff I learned how to use C++. Now, I take CS162 at college and C++ becomes an easy language to use. My knowledge of Windows API is all from my long experience using it. It took some effort developing useful methods and optimizing them over time. It was all worth it though .

C++11 yum yum!

Anton_S

I'm not sure if I used any C++ 11 syntax in that C++ extension, but Ruby C++ extensions as a whole give so much opportunities to writing great plugins in SU. I'm amazed that SU team chose Ruby over all available programming languages. Back then, when SU was first released, Ruby wasn't even popular, but SU team bypassed popularity and chose Ruby because Ruby was both simple and powerful due to a feature in supporting C extensions. Today, Ruby is becoming popular and is improving in performance and in features. Something tells me that SU had and still has really great minds behind it because choosing Ruby was the best path SU team could ever take. Imagine if they chose python or any other high level, limited programming language. SU would have been a totally different story from what it is today. Huge thanks goes to SU team for making SU a very great software for writing powerful plugins.