• Advertisement
  • Popular Tags

  • Popular Now

  • Advertisement
  • Similar Content

    • By lxjk
      Hi guys,
      There are many ways to do light culling in tile-based shading. I've been playing with this idea for a while, and just want to throw it out there.
      Because tile frustums are general small compared to light radius, I tried using cone test to reduce false positives introduced by commonly used sphere-frustum test.
      On top of that, I use distance to camera rather than depth for near/far test (aka. sliced by spheres).
      This method can be naturally extended to clustered light culling as well.
      The following image shows the general ideas

      Performance-wise I get around 15% improvement over sphere-frustum test. You can also see how a single light performs as the following: from left to right (1) standard rendering of a point light; then tiles passed the test of (2) sphere-frustum test; (3) cone test; (4) spherical-sliced cone test

      I put the details in my blog post (https://lxjk.github.io/2018/03/25/Improve-Tile-based-Light-Culling-with-Spherical-sliced-Cone.html), GLSL source code included!
    • 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();
  • Advertisement
  • Advertisement
Sign in to follow this  

OpenGL Question about multiple Vertex Buffer...

This topic is 3830 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

Hi, in opengl, when i load my models using vertex buffer, it's very easy to use only the buffers that i need for a particular model(ex. one model with texture and lighting, the other whithout lighting, the other one with fog, ect...), but in DX, i ran into the problem that you must define you're FVF yourself, so that make thing a little more complicated... How can i use multiple vertex buffer for one object efficietly? Thx for any help!

Share this post

Link to post
Share on other sites
When I need something like that I just have one model with all things I might possibly need(position, normals etc...) and then in vertex I use only things I need now.

Share this post

Link to post
Share on other sites
ok, but do you create multiple vertex buffers or use one big "interleaved"
buffer? I need to be able to use one or more of of the 6 following:

-Vertex positon
-Texture coord 1
-Texture coord 2

Im a beginner in dx but know opengl very well so i just need a simple example or something like that... Thx for ur time.

Share this post

Link to post
Share on other sites
hmm, I would use vertex declarations here. read about it in directX SDK documentation and here . I`m sure you can find more if you search on gamedev. and I use one big buffer. and even if I could have multiple small ones I don`t see any benefit. you just make vertex shader like

struct VS_OUTPUT
float4 pos :POSITION;
float2 tex :TEXCOORD0;

VS_OUTPUT basicVs(float4 pos :POSITION, float2 tex :TEXCOORD0)
float4x4 projView = mul(view, projection);
Output.pos = mul(pos, projView);
Output.tex = tex;
return Output;

if you need only position and tex coords 1. if you needed normals, you would just add :NORMAL etc... notice that what you marked as position in vertex declaration is used as position here.

and for fog. you don`t need it in vertices(unless you are doing something special). in SDK there are several articles about it.

Share this post

Link to post
Share on other sites
Ok, seem to work perfectly for vertex position, color, and normals now,
i used vertex declaration and this time it work, some code was incomplete...

(In fact, im building the dx version of my opengl engine, so im trying
to make both version work in similar maners, then i'll merge them togeter when
the dx version will be more stable)

Share this post

Link to post
Share on other sites
I also want to know, is there is a way to tell dx to use white for example
on all mesh without passing a color buffer each time? I also noticed that
i might not need it when i use lighting, cause the color buffer seem to
have no effect in this case. So im not sure what to do...

Share this post

Link to post
Share on other sites
yeah, color on vertices is pretty useless when rendering textured meshes. or at least I can`t see any use for it. if you don`t want to, or can`t, leave them completely from mesh, you can just leave them uninitialized. I guess default value is 0x000000, but that doesn`t matter. I don`t know what do you do with colors in your shaders, but if you need the same color on every vertex, you can simply add constant to vertex shader or hard-code it.

btw, what are you working on?

Share this post

Link to post
Share on other sites
Hi again, im currently working on building a 3d engine library that now work
very well on OpenGL. It can load models, assign texture to them, and
render them with very little line of code. The class CModels handle all the
loading of the model data and the texture, as well as most of the renderaing part.
I also use my own model format, so that why i needed to keep my array separately.

For example, here is the .h and .cpp file of a simple project rendering one lit and textured model:


#pragma comment(lib, "Vortez3DEngine.lib")

#include "Vortez3DEngine.h"
#include "Common.h"
#include "SafeKill.h"

class CEngine : public CVortez3DEngine {
void InitEngineExt();
void ShutdownEngineExt();
void RenderScene();
void UpdateScene(float ElapsedTime);


#include "MyProject.h"

CEngine *pEngine;
CModel MyModel;

int APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
pEngine = new CEngine;

if(pEngine->InitEngine(&hInstance, 0,0,800,600,1)){


return 0;

void CEngine::InitEngineExt()
pEngine->Camera.SetDefaultValue(1.0f,2500.0f, 0.0f,60.0f, 0.0f,0.0f,0.0f, 100.0f, 1.0f,250.0f, 0.0f,360.0f,-90.0f,90.0f);

MyModel.LoadPrimaryTextureID("MyTexture.bmp", 0, 0);

void CEngine::ShutdownEngineExt()

void CEngine::RenderScene()

// Set OpenGL for 3D Drawing
pEngine->Set3DMode(1, 2500);


// Set the color to pure white
glColor3f(1.0f, 1.0f, 1.0f);

// Begin 3d drawing


//Draw the model with all the availlaible vertex buffer loaded with the model(position, tex1, tex2, normals, fog)


// Set OpenGL for 2D Drawing

glDisable (GL_TEXTURE_2D);
glDisable (GL_DEPTH_TEST);

//Draw the FPS

// Swap the back buffer, drawing the current scene on // the screen

void CEngine::UpdateScene(float ElapsedTime)
// This function is called just before RenderScene(), // so you can update some render related data before //renderain the scene

The engine suppost keyboard and mouse input as well, that can be accessed by using one of the virtuals functions of the engine, and a couple of usefull function too, but i try to keep it to a minimum, making it the most versatile possible, so it's not a "true" engine(cause u have to write OpenGL/DX code...), but close enought...

Check the docs here if u want to know more:

[Edited by - Vortez on October 27, 2007 2:21:55 PM]

Share this post

Link to post
Share on other sites
oh, almost forget to ask, did dx take care of deleting textures, vertex and index buffers automatically or should i call some function to free them???

Share this post

Link to post
Share on other sites
DirectX is COM based, so you need to manually release (ie call ->Release) on any object you let DirectX create for you.

Try turning DirectX debug libraries, they will be slower but you'll also get a list of memory leaks (and other useful debug info).

Share this post

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

  • Advertisement