Hi Sebastian,
Thanks for the reply.
________________________________
From: osg-users [osg-users-boun...@lists.openscenegraph.org] on behalf of
Sebastian Messerschmidt [sebastian.messerschm...@gmx.de]
Sent: Sunday, March 13, 2016 4:03 AM
To: OpenSceneGraph Users
Subject: Re: [osg-users] Running OSG models on OpenGLES2.0
Hi Hyun,
Hi Chris,
I tried most of examples. Now I'm focusing on glsl_simple.osgt as it looks
simple, but only the second row of shapes shows. If I modify the vertex shader
a little, I get to see both first/second row.
Can you tell us which platform you are using? You usually don't have to add
precision qualifiers to make shaders work.
I have Xilinx ZynqMP SoC with MALI 400MP, and I'm running Ubuntu on it. I also
have Yocto built rootfs. I've integrated the MALI OpenGLES2 library/driver
there, and I'm building OSG manually. It fails to compile if I don't add the
precision for float & int in shaders. The OSG build configuration is more or
less as below (it's for 3.4.0), with some addition to point to EGL/OPENGLES2
libraries and headers:
cmake \
-DCMAKE_BUILD_TYPE=Release \
-DBUILD_OSG_EXAMPLES=ON \
-DOPENGL_PROFILE=GLES2 \
-DOPENGL_glu_LIBRARY= \
-DGL_HEADER_HAS_GLINT64:INTERNAL=0 \
-DGL_HEADER_HAS_GLUINT64:INTERNAL=0 \
-DOSG_GLU_AVAILABLE=OFF \
-DOSG_GL1_AVAILABLE=OFF \
-DOSG_GL2_AVAILABLE=OFF \
-DOSG_GL3_AVAILABLE=OFF \
-DOSG_GLES1_AVAILABLE=OFF \
-DOSG_GLES2_AVAILABLE=ON \
-DOPENGL_egl_LIBRARY='-lEGL' \
-DOPENGL_LIBRARY='-lGLESv2' \
-DOSG_GL_DISPLAYLISTS_AVAILABLE=OFF \
-DOSG_GL_MATRICES_AVAILABLE=OFF \
-DOSG_GL_VERTEX_FUNCS_AVAILABLE=OFF \
-DOSG_GL_VERTEX_ARRAY_FUNCS_AVAILABLE=OFF \
-DOSG_GL_FIXED_FUNCTION_AVAILABLE=OFF \
-DOSG_CPP_EXCEPTIONS_AVAILABLE=OFF \
-DPOPPLER_HAS_CAIRO_EXITCODE=0 \
I've received some OSG model (file.osg) from someone, and I was able to run it
on the desktop (OpenGL). I was told the OSG model runs on OpenGLES2.0. For me
to run it on OpenGLES2, I added the precision qualifiers to build, but the
result still doesn't look correct. I'm not sure if more / what modification is
needed. For example, I modified the OSG shader generator, but it didn't help.
Does OSG layers completely abstract underlying APIs (OpenGL, OpenGLES,,,),
meaning the OSG models are API independent? or does each OSG model have some
API specific code? For example, I don't see any precision qualifiers in OSG
examples, and does that mean those models are not for OpenGLES2.0?
OSG doesn't completely abstract the APIs, but it can be built specifically to
work with OpenGL ES, by using the compiler flags you used. You will however
have to put some work into it, since you will have to write shaders. Since you
are not telling us which "shader generator" you are using, it is hard to guess
what you are trying to achieve.
There is not something like "models for OpenGLES2.0". You will have to write
appropriate shaders and might have to run some visitors to change fixed
function pipeline functions in to uniforms/attributes of the model.
For instance osg::Material is not working outside the compatibility -profiles,
so might have to run a visitor, that parses osg::Material instances and
replaces them with uniforms or per-vertex attributes which you will have to
evaluate in the shader.
I'm trying to figure out where the issue comes from: OSG model, OSG layers,
OpenGLES library.
Chris asked you for an example model that is not working. You mentioned the
glsl-simple model, which from a glance doesn't have ES-compatible code. The
easiest thing to do is to start with a model(preferably not containing shaders)
and a simple ES-Shader.
Unfortunately the examples here are relatively rare. Might be a great
opportunity to create some minimalistic core/ES-based shader example and to
extend the OpenGL-ES pseudo loader.
If there are already OSG models confirmed to work with OpenGLES2, I'd use those
to validate my platform. But, none of examples in OpenSceneGraph-Data shows
correct results on my platform (nothing displayed except the glsl_simple.osgt)
comparing to results from desktop with OpenGL. Once my platform is confirmed to
work, I will be able to focus on debugging the model. With lack of OSG / shader
experience, I can't easily tell where the issue comes from, and I'm looking for
references for validation.
Thanks,
-hyun
Thanks,
-hyun
Cheers
Sebastian
________________________________
From: osg-users
[osg-users-boun...@lists.openscenegraph.org<mailto:osg-users-boun...@lists.openscenegraph.org>]
on behalf of Chris Hanson [xe...@alphapixel.com<mailto:xe...@alphapixel.com>]
Sent: Friday, March 11, 2016 5:27 PM
To: OpenSceneGraph Users
Subject: Re: [osg-users] Running OSG models on OpenGLES2.0
OGL ES requires a shader.
Many of the OSG-Data models don't have shaders built into them, and will not
transform and rasterize as a result.
Which OSG model did you try that had most surfaces transparent?
This email and any attachments are intended for the sole use of the named
recipient(s) and contain(s) confidential information that may be proprietary,
privileged or copyrighted under applicable law. If you are not the intended
recipient, do not read, copy, or forward this email message or any attachments.
Delete this email message and any attachments immediately.
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org<mailto:osg-users@lists.openscenegraph.org>
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
This email and any attachments are intended for the sole use of the named
recipient(s) and contain(s) confidential information that may be proprietary,
privileged or copyrighted under applicable law. If you are not the intended
recipient, do not read, copy, or forward this email message or any attachments.
Delete this email message and any attachments immediately.
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
