OpenGL library

[agraham]

Here is a first stab at implementing an OpenGL library. The implementation is a subset of the full Android API but the actual functionality is pretty complete (I think!) as the omitted functions are mainly those that used scaled integer working, I have only implemented the equivalents that use floats.

However it is almost totally untested. I have got it to the point where it can draw a triangle on the screen but my total ignorance of OpenGL makes further progress challenging and I'm not really interested in doing graphics. As it can now draw on-screen most of the further functionality should be OK as it is a very thin wrapper of the OpenGL API. The hard part of integrating the GLSurfaceView with Basic4android and drawing on it is done.

The reason for posting it therefore is to see if there is any interest in it before I waste more time on it, and to see if there is an OpenGL expert out there who would collaborate on testing and debugging it - assuming anyone wants to use it at all!

As an aside I believe that the GLSurfaceView, being based on a standard View, can also be drawn on using the same methods as other Views as well as by the OpenGL renderer but I haven't tried that.

Note that the "demo" needs my Threading library.

EDIT :- Version 1.1 posted. See post #5 for details.

EDIT :- Version 1.2 posted. See post #10 for details.

EDIT :- Version 1.3 posted. See post #16 for details.

EDIT :- Version 1.4 posted. See post #21 for details.

EDIT :- Version 1.5 posted. See post #25 for details.

EDIT :- Version 1.6 posted. See post #35 for details.
EDIT :- Version 1.6 reposted with correct version number. See post #38 for details.

EDIT :- Version 1.7 posted. See post #39 for details.

[Steven Sparrow]

We use openGL extensively in a number of projects and as we are migrating code to the Android and iPhone platforms, one of the biggest stumbling blocks was the lack of a 3D engine in basic4android.

We had already starting an openGL implementation of our own, but after seeing your past contributions to basic4andoid I'm sure your implementaiton is likely to be cleaner and more functional.

Will give it a try and get back to you with our findings.

Keep up the great work !
Steve

[Erel]

Thank you Andy. The documentation is available here: Basic4android - OpenGL

[JogiDroid]

Wow, that's nice, one big feature/lib I have been missing in B4A... I have some experience with OpenGL and lot of intrest for 3d gfx so I'm going to test this feature soon... (week or so..)
Thanks!!!

[agraham]

Version 1.1 now posted has support for all the Android OpenGL Interfaces, namely GL10, GL10Ext, GL11, GL11Ext and GL11ExtensionPack. The constants and functions supported may be found in the Android documentation GL10 - Android SDK | Android Developers. Note the clickable list of Interfaces in the lower left panel.

Many functions have equivalents taking either an array or an Android native Buffer. As Basic4android doesn handle Buffers I have omitted those functions using them. However there are a few functions that exist that only accept a Buffer parameter, for example GL10.glVertexPointer. For those functions I have synthesised an alternative using a float array. Alternatives using int or other types of array are possible if required.

Some functions exist in two forms using the same name but different parameter lists. Basic4android does not suppport this so the figure "2" has been appended to the later version name to allow Basic4android to distinguish them. I think I've found them all but if a particular expected version is not visible that is probably the reason for it.

There may be stupid mistakes and typos but I am pretty sure we can overcome those as they arise and hopefully end up with a working OpenGL implementation for Basic4android.

[Cor]

Thanks agraham,

for your nice and hard work

[gorelshv]

hey Andrew, could you post a sample code? just something basic like making a cube and putting a texture on it. thanks.

[agraham]

Originally Posted by gorelshv

could you post a sample code?

No. I'm a Systems Engineer, not a graphics programmer and I know nothing about actually using OpenGL for graphics work. That is why I asked for collaboration to test the library. I knew some people wanted OpenGL so I have done the work to expose it to Basic4android. I now need feedback and examples of failure from people who know what they are doing so that we can debug the library.

[geocomputing]

Andrew,

In answer to your question of whether anyone wants a gl library I can personally say that I definitely do and I've got lots of uses for it. Having gl is something I've been hoping for and makes b4a an amazing product. Thank you very much for providing it, I'll post any bugs I find.

Many thanks,

Andrew.

[agraham]

Hmm! I didn't think this library would grow like this

Version 1.2 now posted.

GL10 Object name changed to GL1 to reflect that it might support either OpenGL ES 1.0 or 1.1.

Various GL1.xxxPointer functions refined as I now better appreciate what they do.

Added Int as well as Float versions of many functions to improve the orthogonality of what's available. This may need revisiting when someone who really knows what they are doing plays with this library.

Added Matrix and Visibility support objects.

Added GLSurfaceView.RunOnGuiThread so that rendering code can run stuff on the GUI thread.

Improved the demo, not in the graphics but in the structure to show error handling on the rendering thread which would otherwise force close the application as exceptions not on the main thread are not trapped and reported by Basic4android.