Help with shader storage buffers, UAVs, texture buffers, etc.

Recommended Posts

Hi all,

First time poster here, although I've been reading posts here for quite a while. This place has been invaluable for learning graphics programming -- thanks for a great resource!

Right now, I'm working on a graphics abstraction layer for .NET which supports D3D11, Vulkan, and OpenGL at the moment. I have implemented most of my planned features already, and things are working well. Some remaining features that I am planning are Compute Shaders, and some flavor of read-write shader resources. At the moment, my shaders can just get simple read-only access to a uniform (or constant) buffer, a texture, or a sampler. Unfortunately, I'm having a tough time grasping the distinctions between all of the different kinds of read-write resources that are available. In D3D alone, there seem to be 5 or 6 different kinds of resources with similar but different characteristics. On top of that, I get the impression that some of them are more or less "obsoleted" by the newer kinds, and don't have much of a place in modern code. There seem to be a few pivots:

  • The data source/destination (buffer or texture)
  • Read-write or read-only
  • Structured or unstructured (?)
  • Ordered vs unordered (?)

These are just my observations based on a lot of MSDN and OpenGL doc reading. For my library, I'm not interested in exposing every possibility to the user -- just trying to find a good "middle-ground" that can be represented cleanly across API's which is good enough for common scenarios.

Can anyone give a sort of "overview" of the different options, and perhaps compare/contrast the concepts between Direct3D, OpenGL, and Vulkan? I'd also be very interested in hearing how other folks have abstracted these concepts in their libraries.

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


  • Forum Statistics

    • Total Topics
      628736
    • Total Posts
      2984456
  • Similar Content

    • By GreenGodDiary
      Having some issues with a geometry shader in a very basic DX app.
      We have an assignment where we are supposed to render a rotating textured quad, and in the geometry shader duplicate this quad and offset it by its normal. Very basic stuff essentially.
      My issue is that the duplicated quad, when rendered in front of the original quad, seems to fail the Z test and thus the original quad is rendered on top of it.
      Whats even weirder is that this only happens for one of the triangles in the duplicated quad, against one of the original quads triangles.

      Here's a video to show you what happens: Video (ignore the stretched textures)

      Here's my GS: (VS is simple passthrough shader and PS is just as basic)
      struct VS_OUT { float4 Pos : SV_POSITION; float2 UV : TEXCOORD; }; struct VS_IN { float4 Pos : POSITION; float2 UV : TEXCOORD; }; cbuffer cbPerObject : register(b0) { float4x4 WVP; }; [maxvertexcount(6)] void main( triangle VS_IN input[3], inout TriangleStream< VS_OUT > output ) { //Calculate normal float4 faceEdgeA = input[1].Pos - input[0].Pos; float4 faceEdgeB = input[2].Pos - input[0].Pos; float3 faceNormal = normalize(cross(faceEdgeA.xyz, faceEdgeB.xyz)); //Input triangle, transformed for (uint i = 0; i < 3; i++) { VS_OUT element; VS_IN vert = input[i]; element.Pos = mul(vert.Pos, WVP); element.UV = vert.UV; output.Append(element); } output.RestartStrip(); for (uint j = 0; j < 3; j++) { VS_OUT element; VS_IN vert = input[j]; element.Pos = mul(vert.Pos + float4(faceNormal, 0.0f), WVP); element.Pos.xyz; element.UV = vert.UV; output.Append(element); } }  
      I havent used geometry shaders much so im not 100% on what happens behind the scenes.
      Any tips appreciated! 
    • By mister345
      Hi, I'm building a game engine using DirectX11 in c++.
      I need a basic physics engine to handle collisions and motion, and no time to write my own.
      What is the easiest solution for this? Bullet and PhysX both seem too complicated and would still require writing my own wrapper classes, it seems. 
      I found this thing called PAL - physics abstraction layer that can support bullet, physx, etc, but it's so old and no info on how to download or install it.
      The simpler the better. Please let me know, thanks!
    • By Hexaa
      I try to draw lines with different thicknesses using the geometry shader approach from here:
      https://forum.libcinder.org/topic/smooth-thick-lines-using-geometry-shader
      It seems to work great on my development machine (some Intel HD). However, if I try it on my target (Nvidia NVS 300, yes it's old) I get different results. See the attached images. There
      seem to be gaps in my sine signal that the NVS 300 device creates, the intel does what I want and expect in the other picture.
      It's a shame, because I just can't figure out why. I expect it to be the same. I get no Error in the debug output, with enabled native debugging. I disabled culling with CullMode.None. Could it be some z-fighting? I have little clue about it but I tested to play around with the RasterizerStateDescription and DepthBias properties with no success, no change at all. Maybe I miss something there?
      I develop the application with SharpDX btw.
      Any clues or help is very welcome
       


    • By alex1997
      I'm looking to render multiple objects (rectangles) with different shaders. So far I've managed to render one rectangle made out of 2 triangles and apply shader to it, but when it comes to render another I get stucked. Searched for documentations or stuffs that could help me, but everything shows how to render only 1 object. Any tips or help is highly appreciated, thanks!
      Here's my code for rendering one object with shader!
       
      #define GLEW_STATIC #include <stdio.h> #include <GL/glew.h> #include <GLFW/glfw3.h> #include "window.h" #define GLSL(src) "#version 330 core\n" #src // #define ASSERT(expression, msg) if(expression) {fprintf(stderr, "Error on line %d: %s\n", __LINE__, msg);return -1;} int main() { // Init GLFW if (glfwInit() != GL_TRUE) { std::cerr << "Failed to initialize GLFW\n" << std::endl; exit(EXIT_FAILURE); } // Create a rendering window with OpenGL 3.2 context glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3); glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2); glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); glfwWindowHint(GLFW_RESIZABLE, GL_FALSE); // assing window pointer GLFWwindow *window = glfwCreateWindow(800, 600, "OpenGL", NULL, NULL); glfwMakeContextCurrent(window); // Init GLEW glewExperimental = GL_TRUE; if (glewInit() != GLEW_OK) { std::cerr << "Failed to initialize GLEW\n" << std::endl; exit(EXIT_FAILURE); } // ----------------------------- RESOURCES ----------------------------- // // create gl data const GLfloat positions[8] = { -0.5f, -0.5f, 0.5f, -0.5f, 0.5f, 0.5f, -0.5f, 0.5f, }; const GLuint elements[6] = { 0, 1, 2, 2, 3, 0 }; // Create Vertex Array Object GLuint vao; glGenVertexArrays(1, &vao); glBindVertexArray(vao); // Create a Vertex Buffer Object and copy the vertex data to it GLuint vbo; glGenBuffers(1, &vbo); glBindBuffer(GL_ARRAY_BUFFER, vbo); glBufferData(GL_ARRAY_BUFFER, sizeof(positions), positions, GL_STATIC_DRAW); // Specify the layout of the vertex data glEnableVertexAttribArray(0); // layout(location = 0) glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0); // Create a Elements Buffer Object and copy the elements data to it GLuint ebo; glGenBuffers(1, &ebo); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo); glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(elements), elements, GL_STATIC_DRAW); // Create and compile the vertex shader const GLchar *vertexSource = GLSL( layout(location = 0) in vec2 position; void main() { gl_Position = vec4(position, 0.0, 1.0); } ); GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER); glShaderSource(vertexShader, 1, &vertexSource, NULL); glCompileShader(vertexShader); // Create and compile the fragment shader const char* fragmentSource = GLSL( out vec4 gl_FragColor; uniform vec2 u_resolution; void main() { vec2 pos = gl_FragCoord.xy / u_resolution; gl_FragColor = vec4(1.0); } ); GLuint fragmentShader = glCreateShader(GL_FRAGMENT_SHADER); glShaderSource(fragmentShader, 1, &fragmentSource, NULL); glCompileShader(fragmentShader); // Link the vertex and fragment shader into a shader program GLuint shaderProgram = glCreateProgram(); glAttachShader(shaderProgram, vertexShader); glAttachShader(shaderProgram, fragmentShader); glLinkProgram(shaderProgram); glUseProgram(shaderProgram); // get uniform's id by name and set value GLint uRes = glGetUniformLocation(shaderProgram, "u_Resolution"); glUniform2f(uRes, 800.0f, 600.0f); // ---------------------------- RENDERING ------------------------------ // while(!glfwWindowShouldClose(window)) { // Clear the screen to black glClear(GL_COLOR_BUFFER_BIT); glClearColor(0.0f, 0.5f, 1.0f, 1.0f); // Draw a rectangle made of 2 triangles -> 6 vertices glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, NULL); // Swap buffers and poll window events glfwSwapBuffers(window); glfwPollEvents(); } // ---------------------------- CLEARING ------------------------------ // // Delete allocated resources glDeleteProgram(shaderProgram); glDeleteShader(fragmentShader); glDeleteShader(vertexShader); glDeleteBuffers(1, &vbo); glDeleteVertexArrays(1, &vao); return 0; }  
    • By L. Spiro
      Home: https://www.khronos.org/vulkan/
      SDK: http://lunarg.com/vulkan-sdk/
       
      AMD drivers: http://gpuopen.com/gaming-product/vulkan/ (Note that Vulkan support is now part of AMD’s official drivers, so simply getting the latest drivers for your card should give you Vulkan support.)
      NVIDIA drivers: https://developer.nvidia.com/vulkan-driver (Note that Vulkan support is now part of NVIDIA’s official drivers, so simply getting the latest drivers for your card should give you Vulkan support.)
      Intel drivers: http://blogs.intel.com/evangelists/2016/02/16/intel-open-source-graphics-drivers-now-support-vulkan/
       
      Quick reference: https://www.khronos.org/registry/vulkan/specs/1.0/refguide/Vulkan-1.0-web.pdf
      References: https://www.khronos.org/registry/vulkan/specs/1.0/apispec.html
      https://matthewwellings.com/blog/the-new-vulkan-coordinate-system/
       
      GLSL-to-SPIR-V: https://github.com/KhronosGroup/glslang

      Sample code: https://github.com/LunarG/VulkanSamples
      https://github.com/SaschaWillems/Vulkan
      https://github.com/nvpro-samples
      https://github.com/nvpro-samples/gl_vk_chopper
      https://github.com/nvpro-samples/gl_vk_threaded_cadscene
      https://github.com/nvpro-samples/gl_vk_bk3dthreaded
      https://github.com/nvpro-samples/gl_vk_supersampled
      https://github.com/McNopper/Vulkan
      https://github.com/GPUOpen-LibrariesAndSDKs/HelloVulkan
       
      C++: https://github.com/nvpro-pipeline/vkcpp
      https://developer.nvidia.com/open-source-vulkan-c-api

      Getting started: https://vulkan-tutorial.com/
      https://renderdoc.org/vulkan-in-30-minutes.html
      https://www.khronos.org/news/events/vulkan-webinar
      https://developer.nvidia.com/engaging-voyage-vulkan
      https://developer.nvidia.com/vulkan-shader-resource-binding
      https://developer.nvidia.com/vulkan-memory-management
      https://developer.nvidia.com/opengl-vulkan
      https://github.com/vinjn/awesome-vulkan

      Videos: https://www.youtube.com/playlist?list=PLYO7XTAX41FPg08uM_bgPE9HLgDAyzDaZ

      Utilities: https://github.com/GPUOpen-LibrariesAndSDKs/VulkanMemoryAllocator (AMD Memory allocator.)
      https://github.com/GPUOpen-LibrariesAndSDKs/Anvil (AMD Miniature Vulkan engine/framework.)

       
      L. Spiro
  • Popular Now