• Advertisement
  • Popular Tags

  • Popular Now

  • Advertisement
  • Similar Content

    • By racarate
      Hey everybody!
      I am trying to replicate all these cool on-screen debug visuals I see in all the SIGGRAPH and GDC talks, but I really don't know where to start.  The only resource I know of is almost 16 years old:
      http://number-none.com/product/Interactive Profiling, Part 1/index.html
      Does anybody have a more up-to-date reference?  Do people use minimal UI libraries like Dear ImgGui?  Also, If I am profiling OpenGL ES 3.0 (which doesn't have timer queries) is there really anything I can do to measure performance GPU-wise?  Or should I just chart CPU-side frame time?  I feel like this is something people re-invent for every game there has gotta be a tutorial out there... right?
    • By Achivai
      Hey, I am semi-new to 3d-programming and I've hit a snag. I have one object, let's call it Object A. This object has a long int array of 3d xyz-positions stored in it's vbo as an instanced attribute. I am using these numbers to instance object A a couple of thousand times. So far so good. 
      Now I've hit a point where I want to remove one of these instances of object A while the game is running, but I'm not quite sure how to go about it. At first my thought was to update the instanced attribute of Object A and change the positions to some dummy number that I could catch in the vertex shader and then decide there whether to draw the instance of Object A or not, but I think that would be expensive to do while the game is running, considering that it might have to be done several times every frame in some cases. 
      I'm not sure how to proceed, anyone have any tips?
    • 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!
  • Advertisement
  • Advertisement


This topic is now archived and is closed to further replies.

OpenGL OpenGL and DirectX??

This topic is 6078 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

I''d like to know which of the 2 API is either better, easier to learn, better documented....and your personal opinion about them. I know that OpenGL can be used with any language, and DirectX is neither portable like OpenGL is nor can you use any language. But OpenGL only has the 3D graphics and stuff like DirectSound is missing. Is it right that you can implement DirectSound into OpenGL?? and is it still portable as without i.e DirectSound?? And again: which of the 2 API is either better, easier to learn, better documented...?

Share this post

Link to post
Share on other sites
Guest Anonymous Poster
I started developing games about two years ago using Direct x 6.0
,simply because most of the professional software houses use the MS API
It is a matter of fact, useless to deny the evidence !.
A nightmare, I was about to quit with game programming.
Afterwards I shifted to Opengl .
In about 3 monthes time I was able to grasp the basic of 3D graphic programming.
Ok, my previous experience was not probably completely useless but no doubt that the Opengl architecture is much easier ( I do not mean better) than direct x.
The lack of sound and input support as well as of a custom 3d file format , same as .x file, are definitly drawbacks but you
can purchase a book such as "Opengl game programming " which integrate direct sound , direct input and md2 file format in the opengl based game engine.
I am concern about one point, only.
will the graphic cards manufacturers still support opengl in the future ? ( what about GeForce 3.0 and X box ?, for example)
I would appreciate to receive comments of other readers.

Share this post

Link to post
Share on other sites
I can't make it any clearer that this is my personal opinion, and I am not trying to start a flame war here. So for those of you who want to accuse me, know it was you who is wrong.

I find Direct X messy, and alot like windows code. It seems to be in sentence structure rather than programming strucutre, and it doesn't stand out as much as OpenGL. Also, the Direct X code itself looks like a error, so its hard to find an error inside of it(my opinions). I like OpenGL because it is to the point, clean, and usually is easy to spot in code. Not to mention, i dont like MicroSoft, so using Direct X would be aginst my moral code and princpals . That is my opnion, but I suggest you go tke a simple tutorial on both(the basics) and see whihc one suits you better.

PS: Just because I say it is messy, doesnt mean it really is, it is just that I look at it, and it seems messy. Once again, you should check both out.

"I've sparred with creatures from the nine hells themselves... I barely plan on breaking a sweat here, today."~Drizzt Do'Urden

Edited by - Drizzt DoUrden on September 4, 2001 2:57:23 PM

Share this post

Link to post
Share on other sites
>>I find Direct X messy, and alot like windows code<<

i remember years ago when i started on opengl my first thought was, why cant the win16/win32 api''s be designed like this ( i was doing a lot of windows programming at the time )

Share this post

Link to post
Share on other sites
OpenGL is better, it doesn''t need all these SDK downloading of several hundred mbs.

Just one tiny little header called glext.h needs to be downloaded for each new update.

Good luck M$, hehe.

The Game Industry

Share this post

Link to post
Share on other sites
Question: I see openNL/hawkNL and openAL listed here. But what open library can do input like DirectInput?

Now to my input. I have used both directX (D3D and DDraw) and openGL (a little) and I personally perfer OpenGL. It is probably because I do not like microsoft and I personally think openGL is a tiny bit eaiser to use, and also because I could get it to work with Dev-C++ while I could not (after much effort) get DirectX (7 and 8) to work with it.

Now the facts. OpenGL is cross platform DirectX is not. Meaning if you want to write for linux and windows use OGL but if you are just going for windows use OGL and DX.
OpenGL gets the newest features first. Through extentions you can use the newest features on video cards before you can with DX but your code may not work unless people have that card (correct me if i''m wrong). With DX pretty much all your code will work.

Well I could go on but I will advise along with these other people to try both out even thought we are making it sound like OGL is 10 times better. Still try both (unless you are pressed for time).
Oh one more thing OGL can be used with DirectInput, DirectPlay, DirectSound, and the like (only on windows of course).

Hope I helped.


Share this post

Link to post
Share on other sites
I''ve personally found Open GL to be a much better API to work with. It has is flaws. No input support and such but a person can use the good aspects of direct x for those things. Direct 3D gave me a headache when coding. I always came up with errors and had to rewrite a lot of code to get it to do what I wanted. I switched to Open GL a few months ago and have written a lot more code that actually works in a shorter period of time.

As for Anonymous''s concern. As far as I know every major video card manufacturer still plans on supporting Open GL. Nvidia has even released an OpenGL SDK specific for the GeForce 3 cards. And with version 1.3 of OpenGL coming out the future looks good.

As far as X-Box? I would give that a big thumbs down. Microsoft has pretty much based the whole system around programming with Direct X. At least that is what I''ve heard and someone may be able to enlighten me more. Personally why would I want to buy what is basically another PC modified to just play games. When I have an even better one right in front of me now.

Talk to everyone later.

Share this post

Link to post
Share on other sites
I can't say it better.

When I used VB, I used DirectX. Simply because it's the first language I crossed, and because it has all the features needed for games. Later I saw some OpenGL, but it was really a pain with VB.

When I moved to C++ for more speed and control, I started with DirectX too, and bought a book. Although I had a lot of experience with it using VB (it's almost the same, code's just a bit bigger now ) I still found it hard. Then I found NeHe. I immediatly started using OpenGL when I heard impressive games where made with it (Quake III, Half-Life) and I found it's much easier to use than DirectX. (only the setup code in the first lesson was hard, the rest of code is really self-explaining)

I'm creating an engine with it now, and it goes pretty well. The engine is better than all my VB / DirectX engines and everything I created with C++ / DirectX. I'm going to buy the OpenGL superbible 2nd edition, OpenGL game programming and a C++ book soon, to become an OpenGL master because this language is really powerfull and has a future (though it's much easier to use than DirectX)

Oh, and for Input and Sound, you can integrate it with DirectX easily, and the input code is not so hard (I don't know about sound really)

Good luck with it. I really advise you to use OpenGL

Edited by - Everquest on September 5, 2001 1:46:39 AM

Share this post

Link to post
Share on other sites

  • Advertisement