• Advertisement
Sign in to follow this  

OpenGL Stutter / Micro Stutter Even w/ VSync

This topic is 1514 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

I had stuttering issues myself, but it only happened on windowed linux and windowed AND fullscreen windows

My imperfect solution was to interpolate player camera rotation and movement (separately)

I didn't interpolate movement or rotation before, so when i did with rotation it became really smooth.

After that I just added weight to player position (very stupid 'fix',) but it actually works ok

 

like

player.xyz = oldPlayer.xyz * weight  +  newPlayer.xyz * (1.0 - weight);

 

where old and new are only updated each time the physics thread is updated

I'ts not a solution, but if it makes things smooth for you, like it did for me, at least we both know the reason smile.png

the physics thread just didn't update regularly enough because of the variable amount of background work it does and the irregularities in the update frequency

 

Also, for rotation i just interpolated pitch/yaw/roll, because that made things simpler (no need for slerp)

I'm not sure I understand this one completely, but the way I interpret it is having the player's movement depend on the delta between frames? If that is so, then it does do that already. Same for the scrolling of the background and everything else. The whole environment runs off a delta (which made me think of taking that out and seeing what happens when it doesn't - which is why I made the sample program I put on Github to take out all the variables I could).

 

 

Do you have a virus scanner active?

 

No sir, I do not. In fact I killed all running processes that were not critical in both Windows and Linux - and even reformatted Linux (and also upgraded it to Ubuntu 13.10 and installed only the SDL2 libs), AND reinstalled my video drivers in both Linux and Windows.

Share this post


Link to post
Share on other sites
Advertisement

Not sure why I didn't think of this before, but is it possible that your stuttering is caused by the fact that you're writing to the console window every frame? I just tested the sample code on Windows... The regular size for the console window buffer is 80x300 characters, and with that setting, I get no/low stuttering. When I changed the buffer size to 3000x3000, it started stuttering the way you describe, and it was worse when I maximized the console window. The Linux console window probably also has this issue.

 

Another way I can think of to reproduce this would be to pipe the output of your program's stdout to a file.

 

IF you comment out the code that prints to the console, do you still get the stuttering?

Share this post


Link to post
Share on other sites

Not sure why I didn't think of this before, but is it possible that your stuttering is caused by the fact that you're writing to the console window every frame? I just tested the sample code on Windows... The regular size for the console window buffer is 80x300 characters, and with that setting, I get no/low stuttering. When I changed the buffer size to 3000x3000, it started stuttering the way you describe, and it was worse when I maximized the console window. The Linux console window probably also has this issue.

 

Another way I can think of to reproduce this would be to pipe the output of your program's stdout to a file.

 

IF you comment out the code that prints to the console, do you still get the stuttering?

 

Sorry for the very delayed response - been out of the country the past couple weeks. I did try removing all the output statements, piping them to a file, limiting them, etc. and the problem still persists.

Share this post


Link to post
Share on other sites

I'm out of ideas, sorry.

 

 

Haha, it's okay. I am too, and I'm baffled. If I ever figure it out I'll be sure to post. Thank you very much for the help though everybody!!! :)

Share this post


Link to post
Share on other sites

Some quick questions..

 

For how long does a frame stay when it stutters? Are we talking 2-3 frames or more?

 

Can you give some more detailed specs on your test systems?

 

Windows (and most likely Linux) parks unused CPUs and unparks them when needed. This is supposed to be transparent, but it's not. Maybe other games just use more cpu and therefore keep them unparked while you end up just on the line causing it to toggle them all the time?

 

What energy setting are you using? In Windows, make sure you are using High Performance or vendor-specific equivalent.

Share this post


Link to post
Share on other sites

Hello, and thanks for participating!

 

I would say 2-3 frames, if I had to guess. You should be able to replicate it via the sample program I posted on github 

https://github.com/martinisshaken/Sample-SDL2-OpenGL-Program

 

As for system specs, this is the info for my laptop:

 

/proc/cpuinfo:

processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 42
model name : Intel(R) Core(TM) i3-2310M CPU @ 2.10GHz
stepping : 7
microcode : 0x1a
cpu MHz : 2093.189
cache size : 3072 KB
physical id : 0
siblings : 4
core id : 1
cpu cores : 2
 
/proc/meminfo:
MemTotal:        6099052 kB
MemFree:         3653744 kB
Buffers:          119444 kB
Cached:          1361440 kB
 
NOTE: I run ubuntu 32-bit, even though I've 6gigs of ram, hence the mem free being so low. All I have open when running this is 14 chrome tabs.
 
lspci:
00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04)
 

 

Regarding the parked CPU, would this still be an issue if I don't limit frames and just let it run full boar at 700fps? Because the same stuttering issue occurs with or without Vsync enabled.

 

As for energy settings in Linux I have tried using cpu management tools to set the power to performance or else maxing out the CPU. Same for windows with high performance setting.

 

I have also tried setting task priority to very high in Linux and real time in Windows to no avail. Exact same stuttering in the exact same way.

Edited by martinis_shaken

Share this post


Link to post
Share on other sites

Hmm, on Linux, have you ever tried LTTng? It basically creates a recording of your system activity which you can then view using tools like LTTv or an Eclipse plugin. Using that, you might be able to get a better understanding of what actually happens. You can see stuff like interrupts, syscalls and more. Maybe some high-prio process/task comes in, maybe there is some other driver doing something funky, etc.

 

I personally don't have a non-virtual Linux system which I can run it on and I also don't have stuff setup for SDL and or OpenGL on my development machines, so I can't really try to reproduce it at the moment.

 

About CPU parking, I don't really know honestly. All I know is that it has been known to cause hickups in games etc, so I disabled it early on and haven't looked back since. LTTng _might_ show you if cpu parking is related.

Share this post


Link to post
Share on other sites


All I have open when running this is 14 chrome tabs.

And you still wonder about a little stuttering? Probably the browser/some flash thingy needs a little CPU shortly.

Share this post


Link to post
Share on other sites

Hmm, on Linux, have you ever tried LTTng? It basically creates a recording of your system activity which you can then view using tools like LTTv or an Eclipse plugin. Using that, you might be able to get a better understanding of what actually happens. You can see stuff like interrupts, syscalls and more. Maybe some high-prio process/task comes in, maybe there is some other driver doing something funky, etc.

 

I personally don't have a non-virtual Linux system which I can run it on and I also don't have stuff setup for SDL and or OpenGL on my development machines, so I can't really try to reproduce it at the moment.

 

About CPU parking, I don't really know honestly. All I know is that it has been known to cause hickups in games etc, so I disabled it early on and haven't looked back since. LTTng _might_ show you if cpu parking is related.

 

Just tried out LTTng and it dumped 60MB of data (which babeltrace spits out to my stdout) for only 10 second of gameplay. Wow. May install Eclipse to try and interpret the trace data. Tried plugging it all into an IDE when I set it up with visual studio, but trace data there didn't seem to help. The most valuable trace information so far is what I've posted in some other posts where I've screens that show how long each frame takes using c++11 chrono. I can't imagine system calls and other processes really interfering with the code, given that it happens the same way across multiple systems at the same times. I tried recording it to post a video, but it seems my computer can't handle that. Will try fraps or something in Windows and see if I can record with that.

Share this post


Link to post
Share on other sites

LTTng can indeed create alot of data if there's alot of things going on. :) You will most likely want to use some visualizer in order to make sense of it. The Eclipse plugin can apparently also be run standalone. Tracing is one of the best ways to debug these sorts of issues since you get history and in this case also a wider perspective (full OS).

Share this post


Link to post
Share on other sites
Sign in to follow this  

  • Advertisement
  • Advertisement
  • Popular Tags

  • Advertisement
  • Popular Now

  • Similar Content

    • By reenigne
      For those that don't know me. I am the individual who's two videos are listed here under setup for https://wiki.libsdl.org/Tutorials
      I also run grhmedia.com where I host the projects and code for the tutorials I have online.
      Recently, I received a notice from youtube they will be implementing their new policy in protecting video content as of which I won't be monetized till I meat there required number of viewers and views each month.

      Frankly, I'm pretty sick of youtube. I put up a video and someone else learns from it and puts up another video and because of the way youtube does their placement they end up with more views.
      Even guys that clearly post false information such as one individual who said GLEW 2.0 was broken because he didn't know how to compile it. He in short didn't know how to modify the script he used because he didn't understand make files and how the requirements of the compiler and library changes needed some different flags.

      At the end of the month when they implement this I will take down the content and host on my own server purely and it will be a paid system and or patreon. 

      I get my videos may be a bit dry, I generally figure people are there to learn how to do something and I rather not waste their time. 
      I used to also help people for free even those coming from the other videos. That won't be the case any more. I used to just take anyone emails and work with them my email is posted on the site.

      I don't expect to get the required number of subscribers in that time or increased views. Even if I did well it wouldn't take care of each reoccurring month.
      I figure this is simpler and I don't plan on putting some sort of exorbitant fee for a monthly subscription or the like.
      I was thinking on the lines of a few dollars 1,2, and 3 and the larger subscription gets you assistance with the content in the tutorials if needed that month.
      Maybe another fee if it is related but not directly in the content. 
      The fees would serve to cut down on the number of people who ask for help and maybe encourage some of the people to actually pay attention to what is said rather than do their own thing. That actually turns out to be 90% of the issues. I spent 6 hours helping one individual last week I must have asked him 20 times did you do exactly like I said in the video even pointed directly to the section. When he finally sent me a copy of the what he entered I knew then and there he had not. I circled it and I pointed out that wasn't what I said to do in the video. I didn't tell him what was wrong and how I knew that way he would go back and actually follow what it said to do. He then reported it worked. Yea, no kidding following directions works. But hey isn't alone and well its part of the learning process.

      So the point of this isn't to be a gripe session. I'm just looking for a bit of feed back. Do you think the fees are unreasonable?
      Should I keep the youtube channel and do just the fees with patreon or do you think locking the content to my site and require a subscription is an idea.

      I'm just looking at the fact it is unrealistic to think youtube/google will actually get stuff right or that youtube viewers will actually bother to start looking for more accurate videos. 
    • By Balma Alparisi
      i got error 1282 in my code.
      sf::ContextSettings settings; settings.majorVersion = 4; settings.minorVersion = 5; settings.attributeFlags = settings.Core; sf::Window window; window.create(sf::VideoMode(1600, 900), "Texture Unit Rectangle", sf::Style::Close, settings); window.setActive(true); window.setVerticalSyncEnabled(true); glewInit(); GLuint shaderProgram = createShaderProgram("FX/Rectangle.vss", "FX/Rectangle.fss"); float vertex[] = { -0.5f,0.5f,0.0f, 0.0f,0.0f, -0.5f,-0.5f,0.0f, 0.0f,1.0f, 0.5f,0.5f,0.0f, 1.0f,0.0f, 0.5,-0.5f,0.0f, 1.0f,1.0f, }; GLuint indices[] = { 0,1,2, 1,2,3, }; GLuint vao; glGenVertexArrays(1, &vao); glBindVertexArray(vao); GLuint vbo; glGenBuffers(1, &vbo); glBindBuffer(GL_ARRAY_BUFFER, vbo); glBufferData(GL_ARRAY_BUFFER, sizeof(vertex), vertex, GL_STATIC_DRAW); GLuint ebo; glGenBuffers(1, &ebo); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo); glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices,GL_STATIC_DRAW); glVertexAttribPointer(0, 3, GL_FLOAT, false, sizeof(float) * 5, (void*)0); glEnableVertexAttribArray(0); glVertexAttribPointer(1, 2, GL_FLOAT, false, sizeof(float) * 5, (void*)(sizeof(float) * 3)); glEnableVertexAttribArray(1); GLuint texture[2]; glGenTextures(2, texture); glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, texture[0]); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); sf::Image* imageOne = new sf::Image; bool isImageOneLoaded = imageOne->loadFromFile("Texture/container.jpg"); if (isImageOneLoaded) { glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, imageOne->getSize().x, imageOne->getSize().y, 0, GL_RGBA, GL_UNSIGNED_BYTE, imageOne->getPixelsPtr()); glGenerateMipmap(GL_TEXTURE_2D); } delete imageOne; glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_2D, texture[1]); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); sf::Image* imageTwo = new sf::Image; bool isImageTwoLoaded = imageTwo->loadFromFile("Texture/awesomeface.png"); if (isImageTwoLoaded) { glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, imageTwo->getSize().x, imageTwo->getSize().y, 0, GL_RGBA, GL_UNSIGNED_BYTE, imageTwo->getPixelsPtr()); glGenerateMipmap(GL_TEXTURE_2D); } delete imageTwo; glUniform1i(glGetUniformLocation(shaderProgram, "inTextureOne"), 0); glUniform1i(glGetUniformLocation(shaderProgram, "inTextureTwo"), 1); GLenum error = glGetError(); std::cout << error << std::endl; sf::Event event; bool isRunning = true; while (isRunning) { while (window.pollEvent(event)) { if (event.type == event.Closed) { isRunning = false; } } glClear(GL_COLOR_BUFFER_BIT); if (isImageOneLoaded && isImageTwoLoaded) { glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, texture[0]); glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_2D, texture[1]); glUseProgram(shaderProgram); } glBindVertexArray(vao); glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, nullptr); glBindVertexArray(0); window.display(); } glDeleteVertexArrays(1, &vao); glDeleteBuffers(1, &vbo); glDeleteBuffers(1, &ebo); glDeleteProgram(shaderProgram); glDeleteTextures(2,texture); return 0; } and this is the vertex shader
      #version 450 core layout(location=0) in vec3 inPos; layout(location=1) in vec2 inTexCoord; out vec2 TexCoord; void main() { gl_Position=vec4(inPos,1.0); TexCoord=inTexCoord; } and the fragment shader
      #version 450 core in vec2 TexCoord; uniform sampler2D inTextureOne; uniform sampler2D inTextureTwo; out vec4 FragmentColor; void main() { FragmentColor=mix(texture(inTextureOne,TexCoord),texture(inTextureTwo,TexCoord),0.2); } I was expecting awesomeface.png on top of container.jpg

    • By khawk
      We've just released all of the source code for the NeHe OpenGL lessons on our Github page at https://github.com/gamedev-net/nehe-opengl. code - 43 total platforms, configurations, and languages are included.
      Now operated by GameDev.net, NeHe is located at http://nehe.gamedev.net where it has been a valuable resource for developers wanting to learn OpenGL and graphics programming.

      View full story
    • By TheChubu
      The Khronos™ Group, an open consortium of leading hardware and software companies, announces from the SIGGRAPH 2017 Conference the immediate public availability of the OpenGL® 4.6 specification. OpenGL 4.6 integrates the functionality of numerous ARB and EXT extensions created by Khronos members AMD, Intel, and NVIDIA into core, including the capability to ingest SPIR-V™ shaders.
      SPIR-V is a Khronos-defined standard intermediate language for parallel compute and graphics, which enables content creators to simplify their shader authoring and management pipelines while providing significant source shading language flexibility. OpenGL 4.6 adds support for ingesting SPIR-V shaders to the core specification, guaranteeing that SPIR-V shaders will be widely supported by OpenGL implementations.
      OpenGL 4.6 adds the functionality of these ARB extensions to OpenGL’s core specification:
      GL_ARB_gl_spirv and GL_ARB_spirv_extensions to standardize SPIR-V support for OpenGL GL_ARB_indirect_parameters and GL_ARB_shader_draw_parameters for reducing the CPU overhead associated with rendering batches of geometry GL_ARB_pipeline_statistics_query and GL_ARB_transform_feedback_overflow_querystandardize OpenGL support for features available in Direct3D GL_ARB_texture_filter_anisotropic (based on GL_EXT_texture_filter_anisotropic) brings previously IP encumbered functionality into OpenGL to improve the visual quality of textured scenes GL_ARB_polygon_offset_clamp (based on GL_EXT_polygon_offset_clamp) suppresses a common visual artifact known as a “light leak” associated with rendering shadows GL_ARB_shader_atomic_counter_ops and GL_ARB_shader_group_vote add shader intrinsics supported by all desktop vendors to improve functionality and performance GL_KHR_no_error reduces driver overhead by allowing the application to indicate that it expects error-free operation so errors need not be generated In addition to the above features being added to OpenGL 4.6, the following are being released as extensions:
      GL_KHR_parallel_shader_compile allows applications to launch multiple shader compile threads to improve shader compile throughput WGL_ARB_create_context_no_error and GXL_ARB_create_context_no_error allow no error contexts to be created with WGL or GLX that support the GL_KHR_no_error extension “I’m proud to announce OpenGL 4.6 as the most feature-rich version of OpenGL yet. We've brought together the most popular, widely-supported extensions into a new core specification to give OpenGL developers and end users an improved baseline feature set. This includes resolving previous intellectual property roadblocks to bringing anisotropic texture filtering and polygon offset clamping into the core specification to enable widespread implementation and usage,” said Piers Daniell, chair of the OpenGL Working Group at Khronos. “The OpenGL working group will continue to respond to market needs and work with GPU vendors to ensure OpenGL remains a viable and evolving graphics API for all its customers and users across many vital industries.“
      The OpenGL 4.6 specification can be found at https://khronos.org/registry/OpenGL/index_gl.php. The GLSL to SPIR-V compiler glslang has been updated with GLSL 4.60 support, and can be found at https://github.com/KhronosGroup/glslang.
      Sophisticated graphics applications will also benefit from a set of newly released extensions for both OpenGL and OpenGL ES to enable interoperability with Vulkan and Direct3D. These extensions are named:
      GL_EXT_memory_object GL_EXT_memory_object_fd GL_EXT_memory_object_win32 GL_EXT_semaphore GL_EXT_semaphore_fd GL_EXT_semaphore_win32 GL_EXT_win32_keyed_mutex They can be found at: https://khronos.org/registry/OpenGL/index_gl.php
      Industry Support for OpenGL 4.6
      “With OpenGL 4.6 our customers have an improved set of core features available on our full range of OpenGL 4.x capable GPUs. These features provide improved rendering quality, performance and functionality. As the graphics industry’s most popular API, we fully support OpenGL and will continue to work closely with the Khronos Group on the development of new OpenGL specifications and extensions for our customers. NVIDIA has released beta OpenGL 4.6 drivers today at https://developer.nvidia.com/opengl-driver so developers can use these new features right away,” said Bob Pette, vice president, Professional Graphics at NVIDIA.
      "OpenGL 4.6 will be the first OpenGL release where conformant open source implementations based on the Mesa project will be deliverable in a reasonable timeframe after release. The open sourcing of the OpenGL conformance test suite and ongoing work between Khronos and X.org will also allow for non-vendor led open source implementations to achieve conformance in the near future," said David Airlie, senior principal engineer at Red Hat, and developer on Mesa/X.org projects.

      View full story
    • By _OskaR
      Hi,
      I have an OpenGL application but without possibility to wite own shaders.
      I need to perform small VS modification - is possible to do it in an alternative way? Do we have apps or driver modifictions which will catch the shader sent to GPU and override it?
  • Advertisement