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    • By Fadey Duh
      Good evening everyone!

      I was wondering if there is something equivalent of  GL_NV_blend_equation_advanced for AMD?
      Basically I'm trying to find more compatible version of it.

      Thank you!
    • By Jens Eckervogt
      Hello guys, 
       
      Please tell me! 
      How do I know? Why does wavefront not show for me?
      I already checked I have non errors yet.
      using OpenTK; using System.Collections.Generic; using System.IO; using System.Text; namespace Tutorial_08.net.sourceskyboxer { public class WaveFrontLoader { private static List<Vector3> inPositions; private static List<Vector2> inTexcoords; private static List<Vector3> inNormals; private static List<float> positions; private static List<float> texcoords; private static List<int> indices; public static RawModel LoadObjModel(string filename, Loader loader) { inPositions = new List<Vector3>(); inTexcoords = new List<Vector2>(); inNormals = new List<Vector3>(); positions = new List<float>(); texcoords = new List<float>(); indices = new List<int>(); int nextIdx = 0; using (var reader = new StreamReader(File.Open("Contents/" + filename + ".obj", FileMode.Open), Encoding.UTF8)) { string line = reader.ReadLine(); int i = reader.Read(); while (true) { string[] currentLine = line.Split(); if (currentLine[0] == "v") { Vector3 pos = new Vector3(float.Parse(currentLine[1]), float.Parse(currentLine[2]), float.Parse(currentLine[3])); inPositions.Add(pos); if (currentLine[1] == "t") { Vector2 tex = new Vector2(float.Parse(currentLine[1]), float.Parse(currentLine[2])); inTexcoords.Add(tex); } if (currentLine[1] == "n") { Vector3 nom = new Vector3(float.Parse(currentLine[1]), float.Parse(currentLine[2]), float.Parse(currentLine[3])); inNormals.Add(nom); } } if (currentLine[0] == "f") { Vector3 pos = inPositions[0]; positions.Add(pos.X); positions.Add(pos.Y); positions.Add(pos.Z); Vector2 tc = inTexcoords[0]; texcoords.Add(tc.X); texcoords.Add(tc.Y); indices.Add(nextIdx); ++nextIdx; } reader.Close(); return loader.loadToVAO(positions.ToArray(), texcoords.ToArray(), indices.ToArray()); } } } } } And It have tried other method but it can't show for me.  I am mad now. Because any OpenTK developers won't help me.
      Please help me how do I fix.

      And my download (mega.nz) should it is original but I tried no success...
      - Add blend source and png file here I have tried tried,.....  
       
      PS: Why is our community not active? I wait very longer. Stop to lie me!
      Thanks !
    • By codelyoko373
      I wasn't sure if this would be the right place for a topic like this so sorry if it isn't.
      I'm currently working on a project for Uni using FreeGLUT to make a simple solar system simulation. I've got to the point where I've implemented all the planets and have used a Scene Graph to link them all together. The issue I'm having with now though is basically the planets and moons orbit correctly at their own orbit speeds.
      I'm not really experienced with using matrices for stuff like this so It's likely why I can't figure out how exactly to get it working. This is where I'm applying the transformation matrices, as well as pushing and popping them. This is within the Render function that every planet including the sun and moons will have and run.
      if (tag != "Sun") { glRotatef(orbitAngle, orbitRotation.X, orbitRotation.Y, orbitRotation.Z); } glPushMatrix(); glTranslatef(position.X, position.Y, position.Z); glRotatef(rotationAngle, rotation.X, rotation.Y, rotation.Z); glScalef(scale.X, scale.Y, scale.Z); glDrawElements(GL_TRIANGLES, mesh->indiceCount, GL_UNSIGNED_SHORT, mesh->indices); if (tag != "Sun") { glPopMatrix(); } The "If(tag != "Sun")" parts are my attempts are getting the planets to orbit correctly though it likely isn't the way I'm meant to be doing it. So I was wondering if someone would be able to help me? As I really don't have an idea on what I would do to get it working. Using the if statement is truthfully the closest I've got to it working but there are still weird effects like the planets orbiting faster then they should depending on the number of planets actually be updated/rendered.
    • By Jens Eckervogt
      Hello everyone, 
      I have problem with texture
      using System; using OpenTK; using OpenTK.Input; using OpenTK.Graphics; using OpenTK.Graphics.OpenGL4; using System.Drawing; using System.Reflection; namespace Tutorial_05 { class Game : GameWindow { private static int WIDTH = 1200; private static int HEIGHT = 720; private static KeyboardState keyState; private int vaoID; private int vboID; private int iboID; private Vector3[] vertices = { new Vector3(-0.5f, 0.5f, 0.0f), // V0 new Vector3(-0.5f, -0.5f, 0.0f), // V1 new Vector3(0.5f, -0.5f, 0.0f), // V2 new Vector3(0.5f, 0.5f, 0.0f) // V3 }; private Vector2[] texcoords = { new Vector2(0, 0), new Vector2(0, 1), new Vector2(1, 1), new Vector2(1, 0) }; private int[] indices = { 0, 1, 3, 3, 1, 2 }; private string vertsrc = @"#version 450 core in vec3 position; in vec2 textureCoords; out vec2 pass_textureCoords; void main(void) { gl_Position = vec4(position, 1.0); pass_textureCoords = textureCoords; }"; private string fragsrc = @"#version 450 core in vec2 pass_textureCoords; out vec4 out_color; uniform sampler2D textureSampler; void main(void) { out_color = texture(textureSampler, pass_textureCoords); }"; private int programID; private int vertexShaderID; private int fragmentShaderID; private int textureID; private Bitmap texsrc; public Game() : base(WIDTH, HEIGHT, GraphicsMode.Default, "Tutorial 05 - Texturing", GameWindowFlags.Default, DisplayDevice.Default, 4, 5, GraphicsContextFlags.Default) { } protected override void OnLoad(EventArgs e) { base.OnLoad(e); CursorVisible = true; GL.GenVertexArrays(1, out vaoID); GL.BindVertexArray(vaoID); GL.GenBuffers(1, out vboID); GL.BindBuffer(BufferTarget.ArrayBuffer, vboID); GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)(vertices.Length * Vector3.SizeInBytes), vertices, BufferUsageHint.StaticDraw); GL.GenBuffers(1, out iboID); GL.BindBuffer(BufferTarget.ElementArrayBuffer, iboID); GL.BufferData(BufferTarget.ElementArrayBuffer, (IntPtr)(indices.Length * sizeof(int)), indices, BufferUsageHint.StaticDraw); vertexShaderID = GL.CreateShader(ShaderType.VertexShader); GL.ShaderSource(vertexShaderID, vertsrc); GL.CompileShader(vertexShaderID); fragmentShaderID = GL.CreateShader(ShaderType.FragmentShader); GL.ShaderSource(fragmentShaderID, fragsrc); GL.CompileShader(fragmentShaderID); programID = GL.CreateProgram(); GL.AttachShader(programID, vertexShaderID); GL.AttachShader(programID, fragmentShaderID); GL.LinkProgram(programID); // Loading texture from embedded resource texsrc = new Bitmap(Assembly.GetEntryAssembly().GetManifestResourceStream("Tutorial_05.example.png")); textureID = GL.GenTexture(); GL.BindTexture(TextureTarget.Texture2D, textureID); GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)All.Linear); GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)All.Linear); GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, texsrc.Width, texsrc.Height, 0, PixelFormat.Bgra, PixelType.UnsignedByte, IntPtr.Zero); System.Drawing.Imaging.BitmapData bitmap_data = texsrc.LockBits(new Rectangle(0, 0, texsrc.Width, texsrc.Height), System.Drawing.Imaging.ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format32bppRgb); GL.TexSubImage2D(TextureTarget.Texture2D, 0, 0, 0, texsrc.Width, texsrc.Height, PixelFormat.Bgra, PixelType.UnsignedByte, bitmap_data.Scan0); texsrc.UnlockBits(bitmap_data); GL.Enable(EnableCap.Texture2D); GL.BufferData(BufferTarget.TextureBuffer, (IntPtr)(texcoords.Length * Vector2.SizeInBytes), texcoords, BufferUsageHint.StaticDraw); GL.BindAttribLocation(programID, 0, "position"); GL.BindAttribLocation(programID, 1, "textureCoords"); } protected override void OnResize(EventArgs e) { base.OnResize(e); GL.Viewport(0, 0, ClientRectangle.Width, ClientRectangle.Height); } protected override void OnUpdateFrame(FrameEventArgs e) { base.OnUpdateFrame(e); keyState = Keyboard.GetState(); if (keyState.IsKeyDown(Key.Escape)) { Exit(); } } protected override void OnRenderFrame(FrameEventArgs e) { base.OnRenderFrame(e); // Prepare for background GL.Clear(ClearBufferMask.ColorBufferBit); GL.ClearColor(Color4.Red); // Draw traingles GL.EnableVertexAttribArray(0); GL.EnableVertexAttribArray(1); GL.BindVertexArray(vaoID); GL.UseProgram(programID); GL.BindBuffer(BufferTarget.ArrayBuffer, vboID); GL.VertexAttribPointer(0, 3, VertexAttribPointerType.Float, false, 0, IntPtr.Zero); GL.ActiveTexture(TextureUnit.Texture0); GL.BindTexture(TextureTarget.Texture3D, textureID); GL.BindBuffer(BufferTarget.ElementArrayBuffer, iboID); GL.DrawElements(BeginMode.Triangles, indices.Length, DrawElementsType.UnsignedInt, 0); GL.DisableVertexAttribArray(0); GL.DisableVertexAttribArray(1); SwapBuffers(); } protected override void OnClosed(EventArgs e) { base.OnClosed(e); GL.DeleteVertexArray(vaoID); GL.DeleteBuffer(vboID); } } } I can not remember where do I add GL.Uniform2();
    • By Jens Eckervogt
      Hello everyone
      For @80bserver8 nice job - I have found Google search. How did you port from Javascript WebGL to C# OpenTK.?
      I have been searched Google but it shows f***ing Unity 3D. I really want know how do I understand I want start with OpenTK But I want know where is porting of Javascript and C#?
       
      Thanks!
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OpenGL Design advice for a front-end for modern graphics APIs

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I am looking to replace my current DX11-only renderer with something better and to make it easier to support many graphics APIs I am writing a common "front-end" API for the graphics APIs I want to support. The renderer is layered and looks a bit like this (I assume this is a farily common way to organize things):

  1. First there is the high-level renderer, ie. the API that the rest of the game communicates with. It contains concepts such as scene-graphs, meshes, materials, cameras, lights etc.
  2. Below the high-level renderer sits the front-end API for the actual graphics APIs we want to target. This is an API that contains (or can emulate) all important features of the graphics APIs, such as devices, textures, shaders, buffers (vb, ib, cb), pipeline state etc.
  3. Below the front-end API are the actual graphics APIs (DX11, DX12, OpenGL, Vulkan, Metal, libGCM etc). These are loaded in as plugins an can be switched during runtime.

I started writing the front-end API with the mindset that I'll target DX11 first and perhaps add DX12 and Vulkan support later. However, this seems to be a very bad idea especially since I have the rare opportunity to rewrite my whole renderer without having to worry about shipping a game right now. Most people seem to agree that it is better to write the front-end to look like the modern APIs and the emulate (or in some cases simply ignore) the modern-only features for the older APIs.

My question is this: What features of the modern APIs should I expose through the front-end API? I would like to make somewhat good use of DX12 and Vulkan so consider those as the main back-ends for now. In my current version of the API I already moved all state into a PSO-like object which will be the only way to set state, even on older APIs. However, after looking into DX12/Vulkan a bit more (note that I still only have a few hours worth of experience with either) it seems that there are other new object types that ideally should be exposed through the front-end, such as command lists, queues, fences, barriers, semaphores, descriptors and descriptor sets + various pools. What about these? Anything else? Does it make sense to try to wrap them up as they are and can DX12's concepts be mapped to Vulkan's concepts or do I have to abstract some of these into completely new concepts?

Thanks for your time!

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Thanks Hodgman for the detailed response! Incidentally I found an interesting video on Vulkan yesterday at: 

Especially the first and last talks are very interesting. Around the four minute mark there is a slide on what Xenko's renderer exposes. Seems like they went with exposing descriptor sets too, but don't really explain why, just "you can't get around it", and that they went with the Vulkan approach of descriptor sets rather than the DX12 approach (which I cannot comment on at all yet). I also very much like the PSO approach even on older hardware so I think I am going to make them first class objects in the front-end too.

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Seems like they went with exposing descriptor sets too, but don't really explain why, just "you can't get around it",
Yeah, "we can't get around [exposing these as first class concepts]" is an interesting throw-away... I guess it's in the context of wanting to redesign as a "next gen" API.

I mentioned above a way to get the benefits of PSO's without making them first class -- a stateless API built around "draw items" is analogous to PSO's, but doesn't have to expose a PSO-like interface. You can expose a D3D11 or even D3D9 style interface to the draw-item compiler.

To implement a D3D11 style resource binding model, you can create a non-shader visible descriptor heap, and pre-create all your resource-view objects on it (similar to pre-creating D3D11 resource-view objects). Then at draw-submission time (or draw-item creation time), you can copy the sparse collection of views from that non-shader-visible heap into a contiguous table in a shader-visible heap. You manage those tables with a ring-buffer so that you can dynamically create them every frame. Doing it this way won't get you to full benefits of letting the user create static/reusable descriptor tables, but will still be faster than D3D11/GL :)

I actually support both -- my "resource lists" are a simpler abstraction than the entire descriptor model (which is quite low-level and exposes many tricky details, such as CPU<->GPU data synchronisation to its users...), and at creation time my users can specify whether they want an immutable one or a mutable one. Immutable ones can be mapped to pre-created/reusable descriptor tables, while mutable ones can use something closer to the D3D11 emulation system described above, where the tables are dynamically constructed at draw submission time.

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I wonder how hard to would be to just use Vulkan, and then make a Vulkan -> D3D12, or Vulkan -> D3D11, etc... implementation.  I wonder if anyone's working on that...

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I wonder how hard to would be to just use Vulkan, and then make a Vulkan -> D3D12, or Vulkan -> D3D11, etc... implementation.  I wonder if anyone's working on that...

If your interface is well designed it would be trivial.  In the engines I've written it would require writing either a plugin or a new set of .h and .cpp files to implement the new API in wrappers and away you go.

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I wonder how hard to would be to just use Vulkan, and then make a Vulkan -> D3D12, or Vulkan -> D3D11, etc... implementation.  I wonder if anyone's working on that...

If your interface is well designed it would be trivial.  In the engines I've written it would require writing either a plugin or a new set of .h and .cpp files to implement the new API in wrappers and away you go.
I think he means emulating the Vulkan API as is, on top of other APIs.
Sure, it's possible, but performance would not be great. Real ports to each API are best for performance.

Looking into the future, implementing old APIs on top of Vulkan is totally feasible though, and would be a cheap way to port say, D3D11 games to a new platform.

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