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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 Some issues from trying to develop a small engine

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Hello I'm trying to develop a small 3D engine in C# using OpenGL. The issues I write here are not API specific but I just tough it would be good to say what I use. First of all I developed the engine around the Entity ideea. A mesh is a entity, a Pivot is a entity and Camera is a Entity. These are all I have up till now. They have 3 vectors: Position, Rotation and Scale(used only on meshes). I managed to rotate the camera using the mouse and it works well. I'm trying to now to make a Move method that takes a vector as a parameter that will move the entity in the direction it's facing. For instance I'd like to use Move(new GVec3(1,0,0)) to move the camera forward. Right now if I call this it moves my camera but not twards were it's facing. I tried using some matrix transformations but I took those from an example that inverted the z parameter and I'm not sure where in the function should I modify the sign. I think it would be better to talk with someone here and clarify this before I continue. Next issue is that I'm trying to do some raycast picking ( I need more informations such as x,y,z of the interersection, the triangle, the normal of the triangle, the surface etc so that's why I'm not using GL_SELECT). I drew some lines to show me visually how the projected line is positioned. It works well when the camera is at 0,0,0 but after that when I move it backwards the point I click on the screen is no longer the point it shows me. The point it shows me is more and more closer to the center of the screen. Not sure where I go wrong here. Also if I'm going to test everything with raycast then I guess I'll have to use each objects position and rotation and even scale when doing the test. However I have no ideea on how to modify the data to use these informations. I tried looking at some 3D engine's source code but they are very complex and I don't understand a lot from what they do. Could anyone be so nice to help me with these things? Thank you! EDIT: Oh I also know C++ VB and BlitzMax so you can basically write code in any language and I'll understand.

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public void Move(GVec3 p)
//Pos = Pos + p;
GMatrix m = new GMatrix();
Pos.x += m.grid[3, 0];
Pos.y += m.grid[3, 1];
Pos.z += m.grid[3, 2];

This should in theory do the trick right?
Somehow it doesn't. It only works when the rotation is 0,0,0

public void Translate(GVec3 v)
grid[3, 0] = grid[0, 0] * v.x + grid[1, 0] * v.y + grid[2, 0] * v.z + grid[3, 0];
grid[3, 1] = grid[0, 1] * v.x + grid[1, 1] * v.y + grid[2, 1] * v.z + grid[3, 1];
grid[3, 2] = grid[0, 2] * v.x + grid[1, 2] * v.y + grid[2, 2] * v.z + grid[3, 2];
public void Scale(GVec3 v)
grid[0, 0] = grid[0, 0] * v.x;
grid[0, 1] = grid[0, 1] * v.x;
grid[0, 2] = grid[0, 2] * v.x;

grid[1, 0] = grid[1, 0] * v.y;
grid[1, 1] = grid[1, 1] * v.y;
grid[1, 2] = grid[1, 2] * v.y;

grid[2, 0] = grid[2, 0] * v.z;
grid[2, 1] = grid[2, 1] * v.z;
grid[2, 2] = grid[2, 2] * v.z;
public void Rotate(GVec3 v)
float cos_ang,sin_ang;

sin_ang = (float)Math.Sin(v.y);

float m00 = grid[0,0]*cos_ang + grid[2,0]*-sin_ang;
float m01 = grid[0,1]*cos_ang + grid[2,1]*-sin_ang;
float m02 = grid[0,2]*cos_ang + grid[2,2]*-sin_ang;

grid[2,0] = grid[0,0]*sin_ang + grid[2,0]*cos_ang;
grid[2,1] = grid[0,1]*sin_ang + grid[2,1]*cos_ang;
grid[2,2] = grid[0,2]*sin_ang + grid[2,2]*cos_ang;


cos_ang = (float)Math.Cos(v.x);
sin_ang = (float)Math.Sin(v.x);

float m10 = grid[1,0]*cos_ang + grid[2,0]*sin_ang;
float m11 = grid[1,1]*cos_ang + grid[2,1]*sin_ang;
float m12 = grid[1,2]*cos_ang + grid[2,2]*sin_ang;

grid[2,0] = grid[1,0]*-sin_ang + grid[2,0]*cos_ang;
grid[2,1] = grid[1,1]*-sin_ang + grid[2,1]*cos_ang;
grid[2,2] = grid[1,2]*-sin_ang + grid[2,2]*cos_ang;


cos_ang = (float)Math.Cos(v.z);
sin_ang = (float)Math.Sin(v.z);

m00 = grid[0,0]*cos_ang + grid[1,0]*sin_ang;
m01 = grid[0,1]*cos_ang + grid[1,1]*sin_ang;
m02 = grid[0,2]*cos_ang + grid[1,2]*sin_ang;

grid[1,0] = grid[0,0]*-sin_ang + grid[1,0]*cos_ang;
grid[1,1] = grid[0,1]*-sin_ang + grid[1,1]*cos_ang;
grid[1,2] = grid[0,2]*-sin_ang + grid[1,2]*cos_ang;

grid[0, 2] = m02;

This might explain my methods

[Edited by - LorinAtzberger on March 17, 2009 9:42:17 AM]

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Usually you store the axis (orientation) along with the position of each entity. The x axis (right vector) as (1,0,0), the y axis (up vector) as (0,1,0) and the z axis (direction) as (0,0,1). Then, to move an entity about a scalar s you simply add s * entity.direction to entity.position.

Each time you rotate your entity simply update the entity's orientation.

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Yes this should work. But what if I want to use the z of the movement (for let's say strafing). How should I do that?
And by the way if the directions is 0 then it won't move.

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Your direction shouldn't be zero since it's a vector and not a position.

To strafe, you want to move along the right vector.

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I solved that problem. I translated the matrix from a language that uses degrees for sin/cos. C# uses radians. Now that I fixed that I have this set of functions that work perfectly:

public void PositionEntity(GVec3 p)
this.Pos.x = p.x;
this.Pos.y = p.y;
this.Pos.z = -p.z;

public void Move(GVec3 p)
GVec3 np = new GVec3();
np.x = p.x;
np.y = p.y;
np.z = -p.z;
GMatrix mat = new GMatrix();

Pos.x += mat.grid[3, 0];
Pos.y += mat.grid[3, 1];
Pos.z += mat.grid[3, 2];
public void Turn(GVec3 p)
Rot.x += p.x;
Rot.y += p.y;
Rot.z += p.z;

public void ScaleEntity(GVec3 p)
Scale = Scale * p;

Also now that this is working I'm thinking of keeping the object I'm testing the raycast on in the center and rotating then translating the line by - the objects rotation and position. This should work and so I won't have to move each vertext to test it :)

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