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    • By fleissi
      Hey guys!

      I'm new here and I recently started developing my own rendering engine. It's open source, based on OpenGL/DirectX and C++.
      The full source code is hosted on github:

      I would appreciate if people with experience in game development / engine desgin could take a look at my source code. I'm looking for honest, constructive criticism on how to improve the engine.
      I'm currently writing my master's thesis in computer science and in the recent year I've gone through all the basics about graphics programming, learned DirectX and OpenGL, read some articles on Nvidia GPU Gems, read books and integrated some of this stuff step by step into the engine.

      I know about the basics, but I feel like there is some missing link that I didn't get yet to merge all those little pieces together.

      Features I have so far:
      - Dynamic shader generation based on material properties
      - Dynamic sorting of meshes to be renderd based on shader and material
      - Rendering large amounts of static meshes
      - Hierarchical culling (detail + view frustum)
      - Limited support for dynamic (i.e. moving) meshes
      - Normal, Parallax and Relief Mapping implementations
      - Wind animations based on vertex displacement
      - A very basic integration of the Bullet physics engine
      - Procedural Grass generation
      - Some post processing effects (Depth of Field, Light Volumes, Screen Space Reflections, God Rays)
      - Caching mechanisms for textures, shaders, materials and meshes

      Features I would like to have:
      - Global illumination methods
      - Scalable physics
      - Occlusion culling
      - A nice procedural terrain generator
      - Scripting
      - Level Editing
      - Sound system
      - Optimization techniques

      Books I have so far:
      - Real-Time Rendering Third Edition
      - 3D Game Programming with DirectX 11
      - Vulkan Cookbook (not started yet)

      I hope you guys can take a look at my source code and if you're really motivated, feel free to contribute :-)
      There are some videos on youtube that demonstrate some of the features:
      Procedural grass on the GPU
      Procedural Terrain Engine
      Quadtree detail and view frustum culling

      The long term goal is to turn this into a commercial game engine. I'm aware that this is a very ambitious goal, but I'm sure it's possible if you work hard for it.


    • By tj8146
      I have attached my project in a .zip file if you wish to run it for yourself.
      I am making a simple 2d top-down game and I am trying to run my code to see if my window creation is working and to see if my timer is also working with it. Every time I run it though I get errors. And when I fix those errors, more come, then the same errors keep appearing. I end up just going round in circles.  Is there anyone who could help with this? 
      Errors when I build my code:
      1>Renderer.cpp 1>c:\users\documents\opengl\game\game\renderer.h(15): error C2039: 'string': is not a member of 'std' 1>c:\program files (x86)\windows kits\10\include\10.0.16299.0\ucrt\stddef.h(18): note: see declaration of 'std' 1>c:\users\documents\opengl\game\game\renderer.h(15): error C2061: syntax error: identifier 'string' 1>c:\users\documents\opengl\game\game\renderer.cpp(28): error C2511: 'bool Game::Rendering::initialize(int,int,bool,std::string)': overloaded member function not found in 'Game::Rendering' 1>c:\users\documents\opengl\game\game\renderer.h(9): note: see declaration of 'Game::Rendering' 1>c:\users\documents\opengl\game\game\renderer.cpp(35): error C2597: illegal reference to non-static member 'Game::Rendering::window' 1>c:\users\documents\opengl\game\game\renderer.cpp(36): error C2597: illegal reference to non-static member 'Game::Rendering::window' 1>c:\users\documents\opengl\game\game\renderer.cpp(43): error C2597: illegal reference to non-static member 'Game::Rendering::window' 1>Done building project "Game.vcxproj" -- FAILED. ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========  
      #include <GL/glew.h> #include <GLFW/glfw3.h> #include "Renderer.h" #include "Timer.h" #include <iostream> namespace Game { GLFWwindow* window; /* Initialize the library */ Rendering::Rendering() { mClock = new Clock; } Rendering::~Rendering() { shutdown(); } bool Rendering::initialize(uint width, uint height, bool fullscreen, std::string window_title) { if (!glfwInit()) { return -1; } /* Create a windowed mode window and its OpenGL context */ window = glfwCreateWindow(640, 480, "Hello World", NULL, NULL); if (!window) { glfwTerminate(); return -1; } /* Make the window's context current */ glfwMakeContextCurrent(window); glViewport(0, 0, (GLsizei)width, (GLsizei)height); glOrtho(0, (GLsizei)width, (GLsizei)height, 0, 1, -1); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glfwSwapInterval(1); glEnable(GL_SMOOTH); glEnable(GL_DEPTH_TEST); glEnable(GL_BLEND); glDepthFunc(GL_LEQUAL); glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); glEnable(GL_TEXTURE_2D); glLoadIdentity(); return true; } bool Rendering::render() { /* Loop until the user closes the window */ if (!glfwWindowShouldClose(window)) return false; /* Render here */ mClock->reset(); glfwPollEvents(); if (mClock->step()) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glfwSwapBuffers(window); mClock->update(); } return true; } void Rendering::shutdown() { glfwDestroyWindow(window); glfwTerminate(); } GLFWwindow* Rendering::getCurrentWindow() { return window; } } Renderer.h
      #pragma once namespace Game { class Clock; class Rendering { public: Rendering(); ~Rendering(); bool initialize(uint width, uint height, bool fullscreen, std::string window_title = "Rendering window"); void shutdown(); bool render(); GLFWwindow* getCurrentWindow(); private: GLFWwindow * window; Clock* mClock; }; } Timer.cpp
      #include <GL/glew.h> #include <GLFW/glfw3.h> #include <time.h> #include "Timer.h" namespace Game { Clock::Clock() : mTicksPerSecond(50), mSkipTics(1000 / mTicksPerSecond), mMaxFrameSkip(10), mLoops(0) { mLastTick = tick(); } Clock::~Clock() { } bool Clock::step() { if (tick() > mLastTick && mLoops < mMaxFrameSkip) return true; return false; } void Clock::reset() { mLoops = 0; } void Clock::update() { mLastTick += mSkipTics; mLoops++; } clock_t Clock::tick() { return clock(); } } TImer.h
      #pragma once #include "Common.h" namespace Game { class Clock { public: Clock(); ~Clock(); void update(); bool step(); void reset(); clock_t tick(); private: uint mTicksPerSecond; ufloat mSkipTics; uint mMaxFrameSkip; uint mLoops; uint mLastTick; }; } Common.h
      #pragma once #include <cstdio> #include <cstdlib> #include <ctime> #include <cstring> #include <cmath> #include <iostream> namespace Game { typedef unsigned char uchar; typedef unsigned short ushort; typedef unsigned int uint; typedef unsigned long ulong; typedef float ufloat; }  
    • 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 !
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OpenGL Is OpenGL for me?

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I''ve never used OpenGL, but I''ve heard a lot of good things about it. My question is, should I learn it? What are the benefits of it over DirectX? Currently a lot of my programming is done in Delphi. Will that make a difference? Should I be using C to get the most out of OpenGL? My gaming interests are mainly in 2D, but even today many 2D games use a lot of 3D effects and enviroments to enhance their overall appearance. Any advice and or information would be greatly appreciated. P.S. What would be a good book to pick up for a OpenGL newbie like myself.

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OpenGL''s main advantage over DirectX is its portability. It runs on just about any platform, whereas DirectX is exclusively a Windows grapihcs API.

OpenGL is much easier to learn than DirectX because OGL itself isn''t an object oriented API (though you can write your own wrapper for it).

I think you''ll like it a lot if you give it a try. A good book is the "OpenGL Superbible 2nd Ed."... plus the NeHe tutorials are really good too. Between those two you should be up and running in no time.

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Two quick questions...

#1 Is it possible to create a totally 2D game using OpenGL? I've done some looking around but everything I come across seems to be 3D. I'm just worried everything is optimized for 3D and the 2D performance might be lacking. On that note, does OpenGL require 3D hardware or will any standard video card work?

#2 Does it work with "windowed" applications or will everything need to be fullscreen. I've done some fullscreen stuff before and I've found it much harder to debug, I like having the option to run a windowed mode if for nothing else than to debug.

P.S. I like the fact OpenGL is portable. It's one of the things I've been looking for. I am seriously considering moving away from Windows and over to Linux. Of course that transition will take time, but better prepared than not.

P.P.S. "OpenGL Superbible 2nd Ed." looks great, it should be just the reference I need. Does anyone know if the "Delphi Developer's Guide to OpenGL" is any good? The Amazon reviews were at best, mixed.

{Thanks again everyone.}

Edited by - Xorcist on July 17, 2001 3:00:35 AM

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1- Yes you can. OpenGL is not for 3D only but is more used for that. You need OpenGL drivers to use OpenGL.

2- Both works.

If you want to support several platform, have a look @ upcoming OpenML (www.khronos.org using OpenGL) or SDL (libsdl.org).

I suggest you use C or C++ instead of Delphi since delphi is mmmhh.... windows only. (well Linux two now)
But it''s definately not crossplatform.

-* So many things to do, so little time to spend. *-

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Guest Anonymous Poster
Yes, OpenGL works in windowed mode. I remember that if you initialize it by hand, there''s only one flag that you need to set to either make it full screen or windowed. If you use GLUT, i''m not sure.

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theres a lot of very good opengl sites for delphi out there a couple are


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Syntax speaking, OGL is far simpler to set up.
As for features, I think DX has more features.
I slammed my head against DX for a while, and now am learning OGL. Much simpler.
I dont know how Delphi works, so I cant advise you on that.
However, C++ would probably the way to go.
I like the way C++ works...some people don''t...
I would personally learn OGL in C++, if I were you.

I came, I saw, I got programmers block.

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GLUT will do any windowing for you. You can run fullscreen or in a window. If you are in a window, you can switch to fullscreen by calling glutFullscreen(); . GLUT will handle mouse input, keyboard input, or just about any other kind of input. It even has built-in support for spaceballs (little motion-capture type devices... like if you wanted to make a boxing game where you can actually throw punches in real life--as far as I can gather anyway). You can create multiple windows with a couple of lines of code. It will handle menus for you, and overlays, and all kinds of stuff.

Most importantly, it's EASY... it's a good way to learn OpenGL without having to deal with windows in the early stages. Here is a little GLUT "skeleton" prog that just draws a quad.


void RenderScene( void );
void SetupRC( void );
void ChangeSize( GLsizei w, GLsizei h );
void DoKeyboard( unsigned char key_asc, int mX, int mY );
void SpecialKeys(int key, int x, int y);
void Timer(int value);

void main( void )
glutInitDisplayMode( GLUT_RGBA | GLUT_DOUBLE );
glutCreateWindow("My Open GL Program");

//Callback functions
glutTimerFunc(100, Timer, 1);

void SetupRC( void )
glClearColor(0.0f, 0.0f, 0.0f, 0.0f);

void RenderScene( void )

glTranslatef(0.0, 0.0, -100.0);
glColor3f(1.0, 0.0, 0.0);
glVertex2f( -20.0, 1.0);
glVertex2f( -20.0, -1.0);
glVertex2f( -20.0+x, -1.0);
glVertex2f( -20.0+x, 1.0);


// Called by GLUT library when the window has changed size
void ChangeSize(GLsizei w, GLsizei h)
// Prevent a divide by zero
if(h == 0) h = 1;
if(w == 0) w = 1;
// Set Viewport to window dimensions
glViewport(0, 0, w, h);
// Reset coordinate system

if (w <= h)
{ h = h*(h/w); w = w;}
{ w = w*(w/h); h = h;}

GLfloat fAspect = (GLfloat)w/(GLfloat)h;
gluPerspective(70.0f, fAspect, 0.1, 500.0f);


void Timer( int value )
glutTimerFunc(100, Timer, 1);


void DoKeyboard( unsigned char key_asc, int mX, int mY )

void SpecialKeys(int key, int x, int y)
// Refresh the Window

Edited by - smitty1276 on July 22, 2001 1:07:34 AM

Edited by - smitty1276 on July 22, 2001 1:08:53 AM

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OpenGL is probably the best 3D API you can find. I was able to write a small engine which loads and renders a Milkshape3D model in just under 1000 lines of code.

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