Christian
Hi Sebastian,
Thanks for the reply.
------------------------------------------------------------------------
*From:* osg-users [osg-users-boun...@lists.openscenegraph.org
<mailto:osg-users-boun...@lists.openscenegraph.org>] on behalf of
Sebastian Messerschmidt [sebastian.messerschm...@gmx.de
<mailto: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:
...
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.
Can't you try some other GLES applications(plain OpenGL-ES without
OSG) and check their shader code? I believe there is a problem with
your system/driver, as there is no need to explicitly issuing the
precision in normal cases.
All models should work in theory if you have some minimal shader
for it.
Out of my head a minimal shader should look like the following. It
will display a red-colored version of your geometry.
Vertex:
#version 100
attribute vec4 osg_Vertex;
uniform mat4 osg_ModelViewProjectionMatrix;
void main()
{
gl_Position = osg_ModelViewProjectionMatrix * osg_Vertex;
}
Fragment:
#version 100
void main()
{
gl_FragColor = vec4(1,0,0,1);
}
Setting this shader to you scene should display everything
correct. If my code is valid, it should compile without any
precision qualifiers.
Cheers
Sebastian
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
<mailto:osg-users@lists.openscenegraph.org>
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
_______________________________________________
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
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
