Sign in to follow this  
shwasasin

OpenGL Wrong faces displaying gDebugger(FBO/CubeMap)

Recommended Posts

shwasasin    482

Hey Folks,

For the last few weeks I've been working on omni-directional shadow-mapping for my game. I've noticed that gDebugger is showing all six faces of my FBO CubeMap as the exact same texture data, even though I have verified that each camera direction is set up correctly and working normally. I use FBO's (2d) throughout my game for lighting, cartoon edging, as well as post-fx so I'm fairly confident it's implemented okay (though there could be something wrong), no framebuffer status errors have occurred and gDebugger hasn't tripped with any errors so I'm at a loss. I've even tried attaching each face as a separate color attachment then using glDrawBuffer to activate each one as I run through my 6 rendering passes and that has produced the same results.

 

I am targeting OpenGL 2.0, so I cannot use FBO Layering/GeoShaders, so I was wondering if anyone has any pointers on the subject? Is there any settings that if (not)set will copy/render the scene to all 6 faces? I'm more than happy to post some code (specifics would be appreciated only because the code is scattered through numerous files). I have to admit it's pretty much the same as every post I've seen on gd.net about fbo's/cube maps (although I seem to be missing the special sauce and cannot see it). I've tested this with an Intel HD Graphics 4000, NVidia 660M (Optimus technology) both of which produce this issue so it's definitely something I'm (not)doing.

 

Any suggestions are appreciated. Thanks!

Share this post


Link to post
Share on other sites
shwasasin    482

Well after spending all day looking at this issue and drinking wwaayy too much coffee, I solved the issue and wanted to share. As I added FBO CubeMap support to my game, I reduced the number of glBindFramebufferEXT calls by removing the call to 0 after completing each FBO render. So in the case of CubeMaps, I instead attached the CubeMap side, then rendered again. While I admit I haven't read the OGL Spec thoroughly enough with regards to FBO's, this makes a difference and the call to 0 somehow is the sauce making each side render correctly.

 

I wrote a quick example of my problem and solution in the hopes this helps others. Have a good one!

 

Bad:

 

glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fboID );
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_CUBE_MAP_POSITIVE_X, texDesc.nameID, 0);
// Render Scene Here
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_CUBE_MAP_NEGATIVE_X, texDesc.nameID, 0);
// Render Scene Here
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
 
Good:
// Face 0
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fboID );
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_CUBE_MAP_POSITIVE_X, texDesc.nameID, 0);
// Render Scene Here
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
 
// Face 1
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fboID );
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_CUBE_MAP_NEGATIVE_X, texDesc.nameID, 0);
// Render Scene Here
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

  • Similar Content

    • By markshaw001
      Hi i am new to this forum  i wanted to ask for help from all of you i want to generate real time terrain using a 32 bit heightmap i am good at c++ and have started learning Opengl as i am very interested in making landscapes in opengl i have looked around the internet for help about this topic but i am not getting the hang of the concepts and what they are doing can some here suggests me some good resources for making terrain engine please for example like tutorials,books etc so that i can understand the whole concept of terrain generation.
       
    • By KarimIO
      Hey guys. I'm trying to get my application to work on my Nvidia GTX 970 desktop. It currently works on my Intel HD 3000 laptop, but on the desktop, every bind textures specifically from framebuffers, I get half a second of lag. This is done 4 times as I have three RGBA textures and one depth 32F buffer. I tried to use debugging software for the first time - RenderDoc only shows SwapBuffers() and no OGL calls, while Nvidia Nsight crashes upon execution, so neither are helpful. Without binding it runs regularly. This does not happen with non-framebuffer binds.
      GLFramebuffer::GLFramebuffer(FramebufferCreateInfo createInfo) { glGenFramebuffers(1, &fbo); glBindFramebuffer(GL_FRAMEBUFFER, fbo); textures = new GLuint[createInfo.numColorTargets]; glGenTextures(createInfo.numColorTargets, textures); GLenum *DrawBuffers = new GLenum[createInfo.numColorTargets]; for (uint32_t i = 0; i < createInfo.numColorTargets; i++) { glBindTexture(GL_TEXTURE_2D, textures[i]); GLint internalFormat; GLenum format; TranslateFormats(createInfo.colorFormats[i], format, internalFormat); // returns GL_RGBA and GL_RGBA glTexImage2D(GL_TEXTURE_2D, 0, internalFormat, createInfo.width, createInfo.height, 0, format, GL_FLOAT, 0); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); DrawBuffers[i] = GL_COLOR_ATTACHMENT0 + i; glBindTexture(GL_TEXTURE_2D, 0); glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + i, textures[i], 0); } if (createInfo.depthFormat != FORMAT_DEPTH_NONE) { GLenum depthFormat; switch (createInfo.depthFormat) { case FORMAT_DEPTH_16: depthFormat = GL_DEPTH_COMPONENT16; break; case FORMAT_DEPTH_24: depthFormat = GL_DEPTH_COMPONENT24; break; case FORMAT_DEPTH_32: depthFormat = GL_DEPTH_COMPONENT32; break; case FORMAT_DEPTH_24_STENCIL_8: depthFormat = GL_DEPTH24_STENCIL8; break; case FORMAT_DEPTH_32_STENCIL_8: depthFormat = GL_DEPTH32F_STENCIL8; break; } glGenTextures(1, &depthrenderbuffer); glBindTexture(GL_TEXTURE_2D, depthrenderbuffer); glTexImage2D(GL_TEXTURE_2D, 0, depthFormat, createInfo.width, createInfo.height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glBindTexture(GL_TEXTURE_2D, 0); glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, depthrenderbuffer, 0); } if (createInfo.numColorTargets > 0) glDrawBuffers(createInfo.numColorTargets, DrawBuffers); else glDrawBuffer(GL_NONE); if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) std::cout << "Framebuffer Incomplete\n"; glBindFramebuffer(GL_FRAMEBUFFER, 0); width = createInfo.width; height = createInfo.height; } // ... // FBO Creation FramebufferCreateInfo gbufferCI; gbufferCI.colorFormats = gbufferCFs.data(); gbufferCI.depthFormat = FORMAT_DEPTH_32; gbufferCI.numColorTargets = gbufferCFs.size(); gbufferCI.width = engine.settings.resolutionX; gbufferCI.height = engine.settings.resolutionY; gbufferCI.renderPass = nullptr; gbuffer = graphicsWrapper->CreateFramebuffer(gbufferCI); // Bind glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo); // Draw here... // Bind to textures glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, textures[0]); glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_2D, textures[1]); glActiveTexture(GL_TEXTURE2); glBindTexture(GL_TEXTURE_2D, textures[2]); glActiveTexture(GL_TEXTURE3); glBindTexture(GL_TEXTURE_2D, depthrenderbuffer); Here is an extract of my code. I can't think of anything else to include. I've really been butting my head into a wall trying to think of a reason but I can think of none and all my research yields nothing. Thanks in advance!
    • By Adrianensis
      Hi everyone, I've shared my 2D Game Engine source code. It's the result of 4 years working on it (and I still continue improving features ) and I want to share with the community. You can see some videos on youtube and some demo gifs on my twitter account.
      This Engine has been developed as End-of-Degree Project and it is coded in Javascript, WebGL and GLSL. The engine is written from scratch.
      This is not a professional engine but it's for learning purposes, so anyone can review the code an learn basis about graphics, physics or game engine architecture. Source code on this GitHub repository.
      I'm available for a good conversation about Game Engine / Graphics Programming
    • By C0dR
      I would like to introduce the first version of my physically based camera rendering library, written in C++, called PhysiCam.
      Physicam is an open source OpenGL C++ library, which provides physically based camera rendering and parameters. It is based on OpenGL and designed to be used as either static library or dynamic library and can be integrated in existing applications.
       
      The following features are implemented:
      Physically based sensor and focal length calculation Autoexposure Manual exposure Lense distortion Bloom (influenced by ISO, Shutter Speed, Sensor type etc.) Bokeh (influenced by Aperture, Sensor type and focal length) Tonemapping  
      You can find the repository at https://github.com/0x2A/physicam
       
      I would be happy about feedback, suggestions or contributions.

    • By altay
      Hi folks,
      Imagine we have 8 different light sources in our scene and want dynamic shadow map for each of them. The question is how do we generate shadow maps? Do we render the scene for each to get the depth data? If so, how about performance? Do we deal with the performance issues just by applying general methods (e.g. frustum culling)?
      Thanks,
       
  • Popular Now