OpenGL ES 2.0 games possibility

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I've been hankering to start porting a game I've been working on(originally was going to be for Zune HD but they haven't released the damn 3D SDK. Video of it running in windows is available on youtube, where my username is marcusmaximus04) to android but was hesitant due to the lack of OpenGL ES2.0 support in the Android SDK. However, looking through the file system on my nexus one, I spotted the file libGLESv2.so, which appears to be the shared object file for exactly this!

Obviously, I still can't use the normal SDK to use this, but in theory, one could use the NDK to use OpenGL ES 2.0 features(shaders, etc) through that shared object file.

The purpose of this post is three-fold. One I want to know if anyone has any background with using OpenGL through the NDK or knows of any tutorials for doing so(I'm not entirely sure how that would work...). Two, I wanted to bring this to the attention of all the devs out there who might be holding off from using ES 2.0 features. And three, I wanted to let everyone else know that such a thing is possible, just 'cause it's exciting.

At any rate, even if I can't find any tutorials I'll probably start plugging away at getting this to work and this should make for an exciting couple weeks/months.

Since we have this pretty well working(even on non-rooted phones) I'll post a sample apk. It doesn't look like much, but it does prove that we're using OpenGL ES 2.0(this will only work on the Nexus One). I'll also post the libGLESv2_adreno.so shared library in the same zip file. Enjoy .

From http://developer.android.com/guide/t...cs/opengl.html:

note that though Android does include some basic support for OpenGL ES 1.1, the support is not complete, and should not be relied upon at this time.

so official 2.0 support might be a bit off :/

Originally Posted by kozm0naut

From http://developer.android.com/guide/t...cs/opengl.html:



so official 2.0 support might be a bit off :/

Possibly, but it does still support it in the NDK(really, this hardcore graphics stuff should be done in the NDK anyway). Even there it's not really official, but they aren't likely to change the API calls since those are already set in stone by khronos.

Hi Marcus,

to get started, grab the OpenGL ES 2.0 headers from www DOT khronos.org/registry/gles/ and copy the library file from your phone to the NDK installation dir (build/platforms/android-4/arch-arm/usr/lib/). Next you might inspect the libGLESv2.so with objdump to see what functions it provides:
build/prebuilt/linux-x86/arm-eabi-4.2.1/bin/arm-eabi-objdump -t libGLESv2.so

It should have the 2.0 functions like glCompileShader(), glCreateProgram(), etc.

Finally, add the following line to the Android.mk file in the jni/ directory of your Android project:
LOCAL_LDLIBS += -Lbuild/platforms/android-4/arch-arm/usr/lib -lGLESv2

If you're lucky, that should allow you to compile and link OpenGL ES 2.0 code. I cannot try this right now but will as soon as I get my Nexus One on monday

I haven't done any OpenGL ES coding with the NDK, but it should be straightforward if you've written OpenGL (ES) code before. This might be of use: code DOT google.com/p/glesquake/

Originally Posted by robert-qfh

Hi Marcus,

to get started, grab the OpenGL ES 2.0 headers from www DOT khronos.org/registry/gles/ and copy the library file from your phone to the NDK installation dir (build/platforms/android-4/arch-arm/usr/lib/). Next you might inspect the libGLESv2.so with objdump to see what functions it provides:
build/prebuilt/linux-x86/arm-eabi-4.2.1/bin/arm-eabi-objdump -t libGLESv2.so

It should have the 2.0 functions like glCompileShader(), glCreateProgram(), etc.

Finally, add the following line to the Android.mk file in the jni/ directory of your Android project:
LOCAL_LDLIBS += -Lbuild/platforms/android-4/arch-arm/usr/lib -lGLESv2

If you're lucky, that should allow you to compile and link OpenGL ES 2.0 code. I cannot try this right now but will as soon as I get my Nexus One on monday

I haven't done any OpenGL ES coding with the NDK, but it should be straightforward if you've written OpenGL (ES) code before. This might be of use: code DOT google.com/p/glesquake/

Alright! Thanks for the help. I've done a lot of opengl work before and a little bit of opengl es when i had my g1 but haven't ever used the ndk, so that'll get me started.

EDIT: Sweet, I've dumped the list of functions available and it looks like all the appropriate shader functions are there. I'm attaching the full list output from my computer. I actually had to use arm-eabi-strings, since the objs one showed no objects. Regardless, it's looking good on the OpenGL ES2.0 front, and I've already looked into running opengl code from the NDK which is perfectly possible and ok.

ANOTHER EDIT: Haven't quite gotten it to build yet, but I got it to load gl2.h without any complaints. Now I just have a crapload of errors because the sample project I was using(from the ndk samples, san-angeles) was written for OpenGL ES 1.0 and all the things now done in shaders no longer exist(GL_LIGHTING, GL_MATERIAL, etc). Regardless, I'm considering this a success so far, since all that is expected.

YET ANOTHER EDIT: It runs! I'm not displaying anything yet(so it's not really a good test), but I got the shared library to build using OpenGL ES 2.0 and it runs on my phone. Gonna implement a simple program to display a triangle or something just to prove it works and will provide source code/binaries here(also, if anyone has a Droid or knows someone who does, it'd be great if we could test out to make sure this works on the Droid as well)

I just wanted to drop in and say I'm very interested in what y'all are doing I'm of very good at coding. All I know is Java but ill definantly be following yall and keep up the good work

Decided to post a reply, rather than just adding to that one post.

Well, I encountered a fairly large roadblock:

E/libEGL  ( 3366): called unimplemented OpenGL ES API

That's what I see now every time I call one of the functions dealing with ES 2.0. I'm hoping there's another library I can use that'll make that go away, but we might not be as easy as I thought to do this.

That's bad news indeed. I was hoping that everything is in place and Google just didn't release a new NDK with ES 2.0 support yet, but if the libGLESv20.so is merely a stub, we're pretty much out of luck. I'd probably disassemble the file to see if there's actually some code besides "return unimplemented" in there, but even if there was, I'd have no idea on how to continue...

I'm wondering how they render the fancy rain drop effect on the wallpaper. Looks like a perfect fit for a 2.0 fragment shader, however there are a lot of other ways to create that effect.

Originally Posted by robert-qfh

That's bad news indeed. I was hoping that everything is in place and Google just didn't release a new NDK with ES 2.0 support yet, but if the libGLESv20.so is merely a stub, we're pretty much out of luck. I'd probably disassemble the file to see if there's actually some code besides "return unimplemented" in there, but even if there was, I'd have no idea on how to continue...

I'm wondering how they render the fancy rain drop effect on the wallpaper. Looks like a perfect fit for a 2.0 fragment shader, however there are a lot of other ways to create that effect.

Well I managed to view the assembly code, but can't get it into any form that I can/want to read(I know how to read assembly but unless you spend hours with it, it's damn near impossible to decode anything. Plus, I haven't looked at ARM assembly before). Know of a good program to convert it into C?

At any rate, I'll attach the disassembler dump(ran it using arm-eabi-objdump with flags -DS). From looking at it briefly, all the implemented functions look like they might be stubs since they're pretty bare bones and have almost all the same instructions(with a slight modification to one single instruction). But it's hard to tell with assembly. Let me know if you can make anything of it. I had to attach the file in a .zip by the way because it was too big.

SUCCESS!!!! So, it looks like those functions were stubs. Google seems to have done it intentionally for whatever reason. They took the .so that actually worked(libGLESv2_adreno200.so) and shoved it under /system/lib/egl, which the ndk doesn't seem able to access(gives you a runtime error if you linked against it). However, If you just copy that file to /system/lib (yes, this requires root unfortunately) then you can use it. I successfully drew a triangle using shaders .

I'll try to get it to attach that xxx_adreno200.so file to the .apk so it can be used without messing around with such things(and work without root). If I can, then I'll throw it on here so everyone can see. Right now it's just a triangle, but tomorrow: the world.

EDIT: Alright, I attached the .apk(it's in the zip file, xda still doesn't allow posting .apks). I tried to attach the libGLESv2_adreno200.so library to it, so it wouldn't require moving the local one but it just wouldn't accept it. So, at least for the mean time, if you want to actually run that app without having it crash you'll have to do an adb remount and then the following in the terminal(or adb shell) as root:

cd /system/lib/egl
cp libGLESv2_adreno200.so ../

Once you do that, when you run the app it should display a yellowish triangle on a blue background(it was from the second tutorial from the OpenGL ES 2.0 sdk for PowerVX). Like I said, it's not much right now, but it is using custom shaders to display that triangle.

ANOTHER EDIT: I decided to change the test program a little. All I changed was the fragment and vertex shaders, which I made to change the color of the pixels based on where they are on the triangle. This should show(to those of you who know OpenGL) that it really is using custom shaders, since it's one triangle and it's clearly not using fixed-function pipeline shading .