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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 texture mapping really slow

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Hi, I'm working on an opengl engine and for some reason, on my system, it seems that texture mapping is horribly slow.

I'm using ubuntu 64-bit, with ati's own drivers across two monitors.

I've modified a nehe example tutorial to make it as basic as I could to illustrate my problem.

(when I disable double buffering in my main app, I can see the texture rendering line-by-line (it draws maybe 5 lines per second)).

The modified tutorial prints out

Got Doublebuffer Visual!
glX-Version 1.4
Depth 24
Congrats, you have Direct Rendering!

Possibly the problem is that I'm driving 2 different monitors with one video card, causing texture mapping to happen on the cpu side of things?

Anyhow, here is the modified tutorial (stripped down as much as I could). It takes about 30 seconds to texture map a 512x512 texture to a simple QUAD.

* This code was created by Jeff Molofee '99
* (ported to Linux/GLX by Mihael Vrbanec '00)
* [edited for brevity]
* (modified by me to illustrate a test case)

#include <memory.h>

#include <stdio.h>
#include <GL/glx.h>
#include <GL/gl.h>

/* stuff about our window grouped together */
typedef struct {
Display *dpy;
int screen;
Window win;
GLXContext ctx;
XSetWindowAttributes attr;
int x, y;
unsigned int width, height;
unsigned int depth;
} GLWindow;

static int attrListDbl[] = { GLX_RGBA, GLX_DOUBLEBUFFER,
None };

GLWindow GLWin;

/* function called when our window is resized (should only happen in window mode) */
void resizeGLScene(unsigned int width, unsigned int height)
glViewport(0, 0, width, height);

// <added by me, this is the generated texture I am rendering>
int tex;

/* general OpenGL initialization function */
int initGL(GLvoid)
glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
/* we use resizeGLScene once to set up our initial perspective */
resizeGLScene(GLWin.width, GLWin.height);

// <my additions for texture mapping setup>

// initial buffer to copy to texture
int size = 512;
unsigned zeros[size * size];
memset(zeros, 0, size * size * 4);

// make a red square
int xct, yct;
for (yct = 50; yct < 100; ++yct)
for (xct = 50; xct < 100; ++xct)
zeros[yct * size + xct] = 0x000000ff;

glGenTextures(1, &tex);
glBindTexture(GL_TEXTURE_2D, tex);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, size, size, 1,


return True;

/* Here goes our drawing code */
int drawGLScene(GLvoid)

glFrustum(-1.0f, 1.0f, -1.0f, 1.0f, 1.0f, 5.0f);


glBindTexture(GL_TEXTURE_2D, tex);
glColor3f(0.5f, 0.5f, 1.0f);
glTexCoord2f(0.0f, 0.0f);
glVertex3f(-1.0f, 1.0f, -2.0f);
glTexCoord2f(1.0f, 0.0f);
glVertex3f(1.0f, 1.0f, -2.0f);
glTexCoord2f(1.0f, 1.0f);
glVertex3f(1.0f, -1.0f, -2.0f);
glTexCoord2f(0.0f, 1.0f);
glVertex3f(-1.0f, -1.0f, -2.0f);
glXSwapBuffers(GLWin.dpy, GLWin.win);
return True;

/* this function creates our window and sets it up properly */
/* FIXME: bits is currently unused */
Bool createGLWindow(char* title, int width, int height, int bits)
XVisualInfo *vi;
Colormap cmap;
int dpyWidth, dpyHeight;
int i;
int glxMajorVersion, glxMinorVersion;
Window winDummy;
unsigned int borderDummy;

/* set best mode to current */
/* get a connection */
GLWin.dpy = XOpenDisplay(0);
GLWin.screen = DefaultScreen(GLWin.dpy);

vi = glXChooseVisual(GLWin.dpy, GLWin.screen, attrListDbl);
if (vi == NULL)
return 0;
printf("Got Doublebuffered Visual!\n");
glXQueryVersion(GLWin.dpy, &glxMajorVersion, &glxMinorVersion);
printf("glX-Version %d.%d\n", glxMajorVersion, glxMinorVersion);
/* create a GLX context */
GLWin.ctx = glXCreateContext(GLWin.dpy, vi, 0, GL_TRUE);
/* create a color map */
cmap = XCreateColormap(GLWin.dpy, RootWindow(GLWin.dpy, vi->screen),
vi->visual, AllocNone);
GLWin.attr.colormap = cmap;
GLWin.attr.border_pixel = 0;

/* create a window in window mode*/
GLWin.attr.event_mask = ExposureMask | KeyPressMask | ButtonPressMask |
GLWin.win = XCreateWindow(GLWin.dpy, RootWindow(GLWin.dpy, vi->screen),
0, 0, width, height, 0, vi->depth, InputOutput, vi->visual,
CWBorderPixel | CWColormap | CWEventMask, &GLWin.attr);
XMapRaised(GLWin.dpy, GLWin.win);
/* connect the glx-context to the window */
glXMakeCurrent(GLWin.dpy, GLWin.win, GLWin.ctx);
XGetGeometry(GLWin.dpy, GLWin.win, &winDummy, &GLWin.x, &GLWin.y,
&GLWin.width, &GLWin.height, &borderDummy, &GLWin.depth);
printf("Depth %d\n", GLWin.depth);
if (glXIsDirect(GLWin.dpy, GLWin.ctx))
printf("Congrats, you have Direct Rendering!\n");
printf("Sorry, no Direct Rendering possible!\n");
return True;

int main(int argc, char **argv)
XEvent event;

createGLWindow("NeHe's Color Tutorial", 640, 480, 24);

for (;;)

return 0;

Any help will be appreciated.

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first of all disable in every rendering instead set it after resizing window (resize gl window procedure)

glFrustum(-1.0f, 1.0f, -1.0f, 1.0f, 1.0f, 5.0f);

rest of code seems to be fine

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first of all disable in every rendering instead set it after resizing window (resize gl window procedure)[/quote]

Setting projection matrices in every frame is peanuts for the GPU.
I usually do so, because there can be a lot of post processes, HUDs etc.

Things that can hurt performance:
1. No graphics driver installed. Sounds trivial, but I run into the problem. I was disappointed how slow openGL is. Then i realized something is wrong with the driver, i updated it and bam! at least 200 times faster rendering (it was really about 200).

2. You use non power-of-too textures.

3. Other stuff... Maybe for some reason, your openGL switches to "software rendering" instead of hardware rendering. Try to google that, I don't know specifics about why this can happen. Edited by szecs

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aa and one other thing with doublebuffered make sure you ste opengl window to doublebuffered i don't know how you initialize opengl window so there could be the problem

i create ogl window by this:

void __fastcall TFCOpenGL::TWORZ_GL()
angle = 0;
ppp = 0;
int pf;

dc = GetDC( FCOpenGL->Handle );
ZeroMemory( &pfd, sizeof( pfd));
pfd.nSize = sizeof( pfd);
pfd.nVersion = 1;
pfd.iPixelType = PFD_TYPE_RGBA;
pfd.cColorBits = 32;
pfd.cDepthBits = 32; pfd.cStencilBits = 8;
pfd.iLayerType = PFD_MAIN_PLANE;

pf = ChoosePixelFormat(dc, &pfd); /
SetPixelFormat(dc, pf, &pfd);
rc = wglCreateContext(dc);




and make sure that control on what you are displaying is doublebuffered too (*TWinControl)NAME->DoubleBuffered = true; ;] Edited by ___

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Well I've uninstalled the proprietary ati drivers and went to the open source ones and everything is working fine. Thanks for the replys.

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Well I've uninstalled the proprietary ati drivers and went to the open source ones and everything is working fine. Thanks for the replys.

A word on that, ATI drivers generally suck especially on Linux based system, and especially for OpenGL. This high resolution pack for a game uses OpenGL, and half of what was rendered when using ATI drivers, was white rectangles. The way to get it to work was go back to an old driver, 10.5 I believe. That's just in my experience anyway. I was actually doing some texture mapping on a sphere in OpenGL and it worked fine on my computer with a NVIDIA GPU, but when I went to two other computers that used ATI, I noticed a slowdown, and this is on Windows. I've just had really bad experiences with ATI, there really should be another company out there that makes GPUs

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