I just started to use OpenNI and Ogre3D for an animation application. I found the below sample for this integration: OpenNI Ogre Integration Sample. But I noticed that it is developed using DirectX which I am not familiar with. Are there other samples which are using OpenGL?
Ogre actually abstracts away all the rendering code - it can use both DirectX and OpenGL (I've used it with both OpenGL and OpenGLES in the past). You usually have a dialog on start-up that lets you choose between OpenGL and DirectX on windows, and if there's no log file, there usually is some config file which specifies which renderer to use.
Also, all the other samples provided with OpenNI with draw to the screen use OpenGL with GLUT.
This is the linux version of OpenNI Sinbad: https://github.com/ttair/TuxSinbad
Related
I'm attempting to make a video game in Unreal Engine 4.9. I'm building it for Windows, but I'd like to have it use opengl instead of directx in the executable. However, I've found no options that let you do this. Unreal Engine uses OpenGL when it creates executables for Linux and Mac, but there seems to be no way to use OpenGL with Windows.
Am I missing something? Is there some way to force Unreal Engine to use OpenGL in Windows executables?
EDIT: The reason I want to use OpenGL is because I want this game to run without having to install anything on the end user's computer (DirectX has to be installed to work)
Microsoft doesn't really support OpenGL, they typically go out of their way to make it very difficult to use OpenGL on Windows and strongly encourage people to use DirectX instead.
The simplest way to get a working OpenGL context in windows is sometimes to use ANGLE which is a compatibility layer which translates OpenGL calls to DirectX calls. This is what Chrome and Firefox use to support WebGL on windows. I doubt that Unreal Engine is integrated with this, so you might have a hard time.
Edit:
EDIT: The reason I want to use OpenGL is because I want this game to run without having to install anything on the end user's computer (DirectX has to be installed to work)
One thing you could do is cross-compile the Mesa3D drivers, as described here: https://wiki.qt.io/Cross_compiling_Mesa_for_Windows
But then you won't get hardware acceleration.
I am trying to use Cairo library in a C++ application utilizing its GL acceleration in Mac. (I made same tests with its Quartz backend but the performance was disappointing.) It says it supports EGL and GLX. Use of GLX requires (externally installed) XQuartz and opens an XWindow so I lean towards EGL:
Apple's programming guide pages tell to use NSOpenGL*, which this page and others say it uses CGL.
This (2012) page says Mac has EAGL and it is only similar to EGL (I suppose it refers to IOS, not MAC as its EAGL reference links to IOS help pages).
Angle says it supports EGL but it is for Direct3D in windows, as I understand(?)
GLFW v3 is also said to support (in future releases?) but via GLX, it is said (?).
Mali says it has a simulator for Mac but I don't know if it is accelerated or is only for its hardware (it also says it only supports a subset of EGL on different platforms).
Most of the links refer to mobile when EGL is used. I am using Mac OS 10.8 and XCode 4.6. What is the current situation / How can I (if I can) use EGL in Mac (now)?
Here it is
https://github.com/SRA-SiliconValley/cairogles/
clone cairo, checkout branch nsgl. This cairo is our fork of cairo 1.12.14 that has the following enhancement vs the upstream cairo
support OpenGL ES 3.0, and support OpenGL ES 2.0 angle MSAA extension
new convex tessellator for fill circle for msaa compositor
new cairo API - cairo_rounded_rectangle() - it is optimized for MSAA compositor
support gaussian blur for four backends: GL/GLES, quartz, xcb and image
support drop shadow and inset for four backends: GL/GLES, quartz, xcv and image with shaow cache
support faster stroke when stroke width = 1 - we call hairline stroke
add integration for NSOpenGL
various bug fixes and optimization.
On Mac OSX, you have two choices: GLX or NSOpenGL - they are mutually exclusive. You can get mesa glx from macport.
1. To compile for NSOpenGL - ./configure --prefix=your_install_location --enable-gl=yes --enable-nsgl=yes --enable-glx=no --enable-egl=no
To compile for GLX - ./configure --prefix=your_install_location --enable-gl=yes --enable-glx=yes --enable-nsgl=no --enable-egl=no.
If you are interested in egl (no available on mac, but mesa 9.1+ on linux and various embedded platform form has egl) do
./configure --prefix=your_install_location --enable-gl=no --enable-egl=yes --enable-glesv2=yes --enable-glesv3= no ===== this compiles for gles2 drivers.
./confgure --prefix=your_install_location --enable-gl=no --enable-egl=yes --enable-glesv2=no --enable-glesv3=yes ==== this compiles for glesv3 driver (mesa 9.1+ has glesv3)
you can have CFLAGS="-g" for debug or CFLAGS="-O2" for optimization.
cairo gl/gles has 3 GL compositors (rendering paths for GL/GLES backend). The default one is span compositor which is software simulation of AA and is slow. If your driver supports MSAA, use msaa compositor. To use MSAA compositor, you can export CAIRO_GL_COMPOSITOR=msaa in terminal, or you can setenv() in your program.
I have sample code to show cairo for quartz, xcv, image, glx, gel or nsgl. If you are interested, I can send you.
Any bug reports/patches are welcome. I have not have time to get wgl (MS windows) to work yet. Additional, it would be nice to have a d3d backend for cairo, I just don't have time to do that - on the todo list.
Enjoy
yes. cairo has been ported to use nsopengl. I will show you howto. amd sample code if you are interested. performance is much faster than quaetz gl.
You definitely can use angle:
#define GL_GLEXT_PROTOTYPES
#include <GLES2/gl2.h>
#include <EGL/egl.h>
I am trying to experiment with the Qt library on Windows. On their downloads page, I notice that the binaries built using VS2012 are available in two forms, with and without OpenGL. What exactly is the difference between the two? In the OpenGL version, do they have some special API implemented using OpenGL or does all of Qt rendering depend on OpenGL? Also, is there a version of Qt that uses DirectX?
#Raman: The opengl variant is using the desktop opengl version just like with Qt4.
The non-opengl variant is using angle, and you need to have that installed alongside the DirectX SDK to get it working. Angle is an adapter between the directx and the opengles API. Only the latter is support directly by Qt, but unfortunately directx drivers tend to work better on Windows than the opengl(es) ones. There are no plans to support a directx backend inside Qt, so we leave with Google's Angle work in that regard.
As for providing some extra bit, there was a discussion about it recently on the mailing list, that this decision should not be build time, but more like run time. However, no one has stood up just yet to make that work. Hopefully, that will change soon. It is causing confusion for the end users just like, so do not feel alone. ;-)
Hope this explanation helps.
DirectX is supported via the ANGLE based library.
Note that this has changed and as of Qt 5.5 the prebuilt binaries you can download from the Qt website are configured with the -opengl dynamic option. This is what #lpapp above was talking about. Qt defaults to choosing either native OpenGL drivers or ANGLE at run time now.
Qt internally uses OpenGL to render unless you specify otherwise now. You can also render custom OpenGL content using Qt's QOpenGLxxx functions and classes.
For a simple introduction to Qt and OpenGL that covers this and more click here.
I tried to build sample projects in cocos2d-x. When I run the exe files, there's a pop window that tells me that OpenGL 1.5 or higher is needed and I should update my drivers. Unfortunately my PC currently don't have video card. Can I upgrade the OpenGL version in my PC without buying a video card?
My PC currently uses Intel® G33/G31 Express Chipset Family.
Install the Mesa 3D Graphics Library. From the mesa3d (dot) org website, "Mesa includes a special off-screen rendering interface called OSMesa. It's unique in that the interface has no dependencies on any operating system or window system. Mesa's off-screen rendering interface is quite simple. Documentation for it may be found in the Mesa README file and there is an example program in the Mesa distribution (demos/osdemo.c)."
I found out here that Intel® G33/G31 Express Chipset Family can support of up to OpenGL 1.4 only. And the only solution to my problem is to buy a video card.
what is the 3d Graphics Library in source engine for macos?(directx of opengl in half-life2)
DirectX is a proprietary API by Microsoft, it is available on MS Windows and XBox only. OpenGL is crossplatform and it is available on almost every platform.
Edit: Thanks #erjot for your input.