问题
I am trying to get an OpenGL-based rendering engine that relies on OpenGL 3.3 and GLSL 3.3 to run on Ubuntu 13.10 using an AMD Radeon 6950. I want to use the open source drivers (radeon), which rely on Mesa for their OpenGL implementation. Ubuntu 13.10 only provides Mesa 9.2 (implementing OpenGL 3.1) "out of the box". It is however possible to install Mesa 10.1 (implementing OpenGL 3.3) from this PPA as explained in this thread:
StackOverflow: OpenGL & GLSL 3.3 on an HD Graphics 4000 under Ubuntu 12.04
I used the exact same steps as explained there:
1.) Add the PPA Repository
$ sudo add-apt-repository ppa:oibaf/graphics-drivers
2.) Update sources
$ sudo apt-get update
3.) Dist-upgrade (rebuilds many packages)
$ sudo apt-get dist-upgrade
4.) Then I rebooted.
Mesa 10.1 was successfully installed. However, glxinfo, while it now reports that Mesa 10.1 is in use, still reports only OpenGL 3.0 (compat profile) and OpenGL 3.1 (core profile):
$ glxinfo | grep OpenGL
OpenGL vendor string: X.Org
OpenGL renderer string: Gallium 0.4 on AMD CAYMAN
OpenGL core profile version string: 3.1 (Core Profile) Mesa 10.1.0-devel (git-7f57408 saucy-oibaf-ppa+curaga)
OpenGL core profile shading language version string: 1.40
OpenGL core profile context flags: (none)
OpenGL core profile extensions:
OpenGL version string: 3.0 Mesa 10.1.0-devel (git-7f57408 saucy-oibaf-ppa+curaga)
OpenGL shading language version string: 1.30
OpenGL context flags: (none)
OpenGL extensions:
Why is that? How can I enable OpenGL 3.3? As can be seen by comparison in the StackOverflow thread that I mentioned, it is possible to have glxinfo report OpenGL 3.3. I am aware that glxinfo may report the wrong version numbers as per the Mesa 10.1 Release Notes, however the rendering engine I'm trying to run fails because of this.
I use the following code to spawn a window:
glfwOpenWindowHint(GLFW_OPENGL_VERSION_MAJOR, 3);
glfwOpenWindowHint(GLFW_OPENGL_VERSION_MINOR, 3);
glfwOpenWindowHint(GLFW_OPENGL_PROFILE, 0);
if(GL_TRUE != glfwOpenWindow(
_windowDimensions.x, _windowDimensions.y,
0, 0, 0, 0, 32, 0, GLFW_WINDOW))
{
THROW("GLFW error: failed to create window.");
}
When I try to run the rendering engine using this setup, the above exception gets thrown as OpenGL 3.3 is not supported. I can set GLFW_OPENGL_VERSION_MINOR to 0 and then the window opens fine, but an exception will be thrown later as GLSL 3.3 shaders are required.
Also note that the rendering engine runs fine when I use the proprietary fglrx drivers (and then glxinfo reports OpenGL version 4.2), so the application itself really is not the problem, but the supported OpenGL is.
So what am I doing wrong? Why doesn't Mesa 10.1 support OpenGL 3.3 for me? My graphics card certainly supports it.
Here's some additional information that may be useful.
$ apt-cache policy libgl1-mesa-glx
libgl1-mesa-glx:
Installed: 10.1~git1402041945.7f5740+curaga~gd~s
Candidate: 10.1~git1402041945.7f5740+curaga~gd~s
Version table:
*** 10.1~git1402041945.7f5740+curaga~gd~s 0
500 http://ppa.launchpad.net/oibaf/graphics-drivers/ubuntu/ saucy/main amd64 Packages
100 /var/lib/dpkg/status
9.2.1-1ubuntu3 0
500 http://archive.ubuntu.com/ubuntu/ saucy/main amd64 Packages
$ lspci -vv
...snip...
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Cayman PRO [Radeon HD 6950] (prog-if 00 [VGA controller])
Subsystem: Hightech Information System Ltd. Device 2307
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 53
Region 0: Memory at c0000000 (64-bit, prefetchable) [size=256M]
Region 2: Memory at fe620000 (64-bit, non-prefetchable) [size=128K]
Region 4: I/O ports at e000 [size=256]
Expansion ROM at fe600000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel driver in use: radeon
...snip...
$ lsmod | egrep 'radeon|fglrx'
radeon 1402995 3
i2c_algo_bit 13413 1 radeon
ttm 84169 1 radeon
drm_kms_helper 52710 1 radeon
drm 297056 5 ttm,drm_kms_helper,radeon
$ modinfo radeon
filename: /lib/modules/3.11.0-15-generic/kernel/drivers/gpu/drm/radeon/radeon.ko
license: GPL and additional rights
description: ATI Radeon
author: Gareth Hughes, Keith Whitwell, others.
...snip...
firmware: radeon/CAYMAN_smc.bin
firmware: radeon/CAYMAN_rlc.bin
firmware: radeon/CAYMAN_mc.bin
firmware: radeon/CAYMAN_me.bin
firmware: radeon/CAYMAN_pfp.bin
...snip...
srcversion: D174B1E4686391B33437915
alias: pci:v00001002d000099A4sv*sd*bc*sc*i*
alias: pci:v00001002d000099A2sv*sd*bc*sc*i*
...snip...
depends: drm,drm_kms_helper,ttm,i2c-algo-bit
intree: Y
vermagic: 3.11.0-15-generic SMP mod_unload modversions
parm: no_wb:Disable AGP writeback for scratch registers (int)
parm: modeset:Disable/Enable modesetting (int)
parm: dynclks:Disable/Enable dynamic clocks (int)
parm: r4xx_atom:Enable ATOMBIOS modesetting for R4xx (int)
parm: vramlimit:Restrict VRAM for testing (int)
parm: agpmode:AGP Mode (-1 == PCI) (int)
parm: gartsize:Size of PCIE/IGP gart to setup in megabytes (32, 64, etc) (int)
parm: benchmark:Run benchmark (int)
parm: test:Run tests (int)
parm: connector_table:Force connector table (int)
parm: tv:TV enable (0 = disable) (int)
parm: audio:Audio enable (1 = enable) (int)
parm: disp_priority:Display Priority (0 = auto, 1 = normal, 2 = high) (int)
parm: hw_i2c:hw i2c engine enable (0 = disable) (int)
parm: pcie_gen2:PCIE Gen2 mode (-1 = auto, 0 = disable, 1 = enable) (int)
parm: msi:MSI support (1 = enable, 0 = disable, -1 = auto) (int)
parm: lockup_timeout:GPU lockup timeout in ms (defaul 10000 = 10 seconds, 0 = disable) (int)
parm: fastfb:Direct FB access for IGP chips (0 = disable, 1 = enable) (int)
parm: dpm:DPM support (1 = enable, 0 = disable, -1 = auto) (int)
parm: aspm:ASPM support (1 = enable, 0 = disable, -1 = auto) (int)
$ dpkg -S /lib/modules/3.11.0-15-generic/kernel/drivers/gpu/drm/radeon/radeon.ko
linux-image-extra-3.11.0-15-generic: /lib/modules/3.11.0-15-generic/kernel/drivers/gpu/drm/radeon/radeon.ko
$ apt-cache policy linux-image-extra-3.11.0-15-generic
linux-image-extra-3.11.0-15-generic:
Installed: 3.11.0-15.25
Candidate: 3.11.0-15.25
Version table:
*** 3.11.0-15.25 0
500 http://archive.ubuntu.com/ubuntu/ saucy-updates/main amd64 Packages
500 http://archive.ubuntu.com/ubuntu/ saucy-security/main amd64 Packages
100 /var/lib/dpkg/status
回答1:
What they do not tell you, but indirectly imply ("Some drivers don't support all the features required in OpenGL 3.3."), is that in the last official release of Mesa (10.0), GL 3.3 only works on Intel hardware. This is one of the joys of Intel's close involvement with the Mesa project. If you want reliable GL 3.3 support in any form on AMD hardware, you should use fglrx (the proprietary AMD driver) for the time being.
The development release of Mesa 10.1 may implement GL 3.3 on radeon drivers, but you need to request a 3.3 core profile. You are not doing this currently.
This:
glfwOpenWindowHint(GLFW_OPENGL_PROFILE, 0);
Actually needs to be this:
glfwOpenWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
Also, there is no such thing as a GL 3.0 compatibility profile or 3.1 core profile. Profiles were not introduced into OpenGL until 3.2. There is a concept of GL_ARB_compatibility in GL 3.1, but that is not the same thing as a profile; glxinfo is giving misleading information.
回答2:
I answered the thread OP mentions regarding "OpenGL & GLSL 3.3 on an HD Graphics 4000 under Ubuntu 12.04" but I thought I would give the same answer here too considering info seems so scarce. This works for those using freeglut and glew:
so Ive seen a lot of threads surrounding this and I thought here would be a good place to respond. Im running Ubuntu 15.04 with intel ivybridge. After using the "Intel Graphics installer for linux" application, glxinfo gives the following info regarding openGl:
OpenGL core profile version string: 3.3 (Core Profile) Mesa 10.6.0
OpenGL core profile shading language version string: 3.30
OpenGL version string: 3.0 Mesa 10.6.0
OpenGL shading language version string: 1.30
Now from this you can see that the core profile and glsl version are 3.3,but compatible openGl is only 3.0 thus if you want your code to run with 3.3 you need to specify both an opengl core profile and a glsl core profile. The following steps should work if youre using freeglut and glew:
-the glsl #version should specify that you want the core profile:
#version 330 core
-specify you want opengl 3.3:
glutInitContextVersion (3, 3);
-and finally set glewExperimental to true before glewInit():
glewExperimental = GL_TRUE;
hope this helps some people get started :)
来源：https://stackoverflow.com/questions/21565680/how-to-enable-opengl-3-3-using-mesa-10-1-on-ubuntu