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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.
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    • 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#?
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OpenGL problem with glGenVertexArrays

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I can't get basic triangle tutorial to work i have tried everything and nothing helps not even glewExperimental = GL_TRUE;

here is the code, can someone please help me with this, the program crashes on glGenVertexArrays no matter what

[source lang="cpp"]// preprocessor directives
#define DIRECTINPUT_VERSION 0x0800 // direct input version

//#pragma warning(disable : 4995) // #pragma deprecated warning
//#pragma warning(disable : 4996) // deprecated warning
//#pragma warning(disable : 4244) // possible loss of data warning

// included headers
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <string>
#include <vector>
#include <iostream>
#include <fstream>
#include <algorithm>

// opengl headers
#include "GL/glew.h"
#include "GL/freeglut.h"
#include "GL/glfw.h"
#include "GL/glm/glm.hpp"
#include <GL/gl.h>

// input device headers
#include <dinput.h>
#include <xinput.h>

// included libraries
#pragma comment(lib, "glew32.lib")
#pragma comment(lib, "freeglut.lib")
#pragma comment(lib, "glfw.lib")
#pragma comment(lib, "opengl32.lib")

#pragma comment(lib, "dinput8.lib")
#pragma comment(lib, "xinput.lib")

// namespace
using namespace glm;
using namespace std;

// function prototypes
GLuint LoadShaders(const char * vertex_file_path,const char * fragment_file_path);

// main
int main(int argc, char *argv[])
int running = GL_TRUE;
double time;

glewExperimental = GL_TRUE;

// Initialize GLFW

glfwOpenWindowHint(GLFW_FSAA_SAMPLES, 4);

// position window in the center of the screen
GLFWvidmode DesktopSize;
int width = 800;
int height = 600;

// Open an OpenGL window
if(!glfwOpenWindow(800, 600, 0, 0, 0, 0, 32, 8, GLFW_WINDOW))

// disable maximize button
HWND windowHandle = GetForegroundWindow();
long Style = GetWindowLong(windowHandle, GWL_STYLE);
Style &amp;= ~WS_MAXIMIZEBOX; //this makes it still work when WS_MAXIMIZEBOX is actually already toggled off
SetWindowLong(windowHandle, GWL_STYLE, Style);

glfwSetWindowPos((DesktopSize.Width - width) / 2, (DesktopSize.Height - height) / 4);

// setup viewport
glViewport(0, 0, width, height);

// setup projection matrix
float znear = 0.1f;
float zfar = 1000.0f;
glOrtho(0.0f, 1.0f, 1.0f, 0.0f, znear, zfar);

// setup aspect ratio according to screen resolution
// and set fov
float fov = 45.0f; // 90 degrees
gluPerspective(fov, width/height, znear, zfar);

// clear the screen to mid gray
glClearColor(0.5f, 0.5f, 0.5f, 0.0f);

// create vertex array object
GLuint VertexArrayID;
glGenVertexArrays(1, &amp;VertexArrayID);

// compile the shader
GLuint programID = LoadShaders("data/shaders/red.vert", "data/shaders/red.frag");

// vertex positions
static const GLfloat g_vertex_buffer_data[] = {
-1.0f, -1.0f, 0.0f,
1.0f, -1.0f, 0.0f,
0.0f, 1.0f, 0.0f,

// create vertex buffer
GLuint vertexbuffer;
glGenBuffers(1, &amp;vertexbuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(g_vertex_buffer_data), g_vertex_buffer_data, GL_STATIC_DRAW);

// Main loop
time = glfwGetTime();

// OpenGL rendering goes here

// use color shader

// Select and setup the projection matrix
gluPerspective(fov, width/height, znear, zfar);

// Select and setup the modelview matrix
glMatrixMode( GL_MODELVIEW );
gluLookAt(0.0f, 1.0f, 0.0f, // Eye-position
0.0f, 0.0f/*20.0f*/, 0.0f, // View-point
0.0f, 0.0f, 1.0f); // Up-vector

// Draw a rotating triangle

// 1rst attribute buffer : vertices
glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
0, // attribute 0. No particular reason for 0, but must match the layout in the shader.
3, // size
GL_FLOAT, // type
GL_FALSE, // normalized?
0, // stride
(void*)0 // array buffer offset

// Draw the triangle !
glDrawArrays(GL_TRIANGLES, 0, 3); // From index 0 to 3 -> 1 triangle


// Swap front and back rendering buffers

// use vsync based on refresh rate

// Check if ESC key was pressed or window was closed
running = !glfwGetKey(GLFW_KEY_ESC) &amp;&amp; glfwGetWindowParam(GLFW_OPENED);

// Close window and terminate GLFW

// clean up vertex buffer object
glDeleteBuffers(1, &amp;vertexbuffer);
glDeleteVertexArrays(1, &amp;VertexArrayID);

// Exit program

return 0;

GLuint LoadShaders(const char * vertex_file_path,const char * fragment_file_path)
// Create the shaders
GLuint VertexShaderID = glCreateShader(GL_VERTEX_SHADER);
GLuint FragmentShaderID = glCreateShader(GL_FRAGMENT_SHADER);

// Read the Vertex Shader code from the file
string VertexShaderCode;
ifstream VertexShaderStream(vertex_file_path, ios::in);
string Line = "";
while(getline(VertexShaderStream, Line))
VertexShaderCode += "\n" + Line;

// Read the Fragment Shader code from the file
string FragmentShaderCode;
ifstream FragmentShaderStream(fragment_file_path, ios::in);
string Line = "";
while(getline(FragmentShaderStream, Line))
FragmentShaderCode += "\n" + Line;

GLint Result = GL_FALSE;
int InfoLogLength;

// Compile Vertex Shader
printf("Compiling shader : %s\n", vertex_file_path);
char const * VertexSourcePointer = VertexShaderCode.c_str();
glShaderSource(VertexShaderID, 1, &amp;VertexSourcePointer , NULL);

// Check Vertex Shader
glGetShaderiv(VertexShaderID, GL_COMPILE_STATUS, &amp;Result);
glGetShaderiv(VertexShaderID, GL_INFO_LOG_LENGTH, &amp;InfoLogLength);
vector<char> VertexShaderErrorMessage(InfoLogLength);
glGetShaderInfoLog(VertexShaderID, InfoLogLength, NULL, &amp;VertexShaderErrorMessage[0]);
fprintf(stdout, "%s\n", &amp;VertexShaderErrorMessage[0]);

// Compile Fragment Shader
printf("Compiling shader : %s\n", fragment_file_path);
char const * FragmentSourcePointer = FragmentShaderCode.c_str();
glShaderSource(FragmentShaderID, 1, &amp;FragmentSourcePointer , NULL);

// Check Fragment Shader
glGetShaderiv(FragmentShaderID, GL_COMPILE_STATUS, &amp;Result);
glGetShaderiv(FragmentShaderID, GL_INFO_LOG_LENGTH, &amp;InfoLogLength);
vector<char> FragmentShaderErrorMessage(InfoLogLength);
glGetShaderInfoLog(FragmentShaderID, InfoLogLength, NULL, &amp;FragmentShaderErrorMessage[0]);
fprintf(stdout, "%s\n", &amp;FragmentShaderErrorMessage[0]);

// Link the program
fprintf(stdout, "Linking program\n");
GLuint ProgramID = glCreateProgram();
glAttachShader(ProgramID, VertexShaderID);
glAttachShader(ProgramID, FragmentShaderID);

// Check the program
glGetProgramiv(ProgramID, GL_LINK_STATUS, &amp;Result);
glGetProgramiv(ProgramID, GL_INFO_LOG_LENGTH, &amp;InfoLogLength);
//vector<char> ProgramErrorMessage(max(InfoLogLength, int(1)));
//glGetProgramInfoLog(ProgramID, InfoLogLength, NULL, &amp;ProgramErrorMessage[0]);
//fprintf(stdout, "%s\n", &amp;ProgramErrorMessage[0]);


return ProgramID;
}[/source] Edited by proanim

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You're not calling glewInit anywhere in your code; this needs to be called after you create the window but befre you do any GL stuff.

You've also got a lot of redundant projection matrix work there, but that's in addition to this problem.

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Ok that fixed the crash i had, but now i can't get triangle on the screen, i even tried to copy/paste entire main from tutorial to my project and it still doesnt show the triangle. I have absolutely no idea why is this. Can you help? I found tutorial here http://www.opengl-tutorial.org/beginners-tutorials/tutorial-2-the-first-triangle/

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