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Knuckler

OpenGL OpenGL AVI class

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I made an OpenGL AVI player and am sharing it with you guys and gals. This is one of the things that have always seemed elusive to OpenGL programmers; at the least being able to have audio and video in sync. It's based on the nehe playing and loading code. A major downside is that it has a lot of dependencies and requirements.

Its all within the bj namespace.

It uses for libraries:
VFW, vfw32.lib / vfw32.dll Already suppied by windows

FMOD, fmodex_vc.lib If you don't need audio, you can comment out the process_audio and init_fmod functions in the Movie constructor

GLEW, glew32.lib This is for OpenGL. You can replace this with GLEE.h or glext.h. Just make sure there is some OpenGL header that supplies you with the declarations, and that there is already a rendering context created. You also need to have a system capable of using PBOs; basically opengl 2.0

Timer.hpp/cpp - A personal timer class based on the QueryPerformance functions.

NOTE: The audio for the AVI must be in PCM16 format. I'm sorry. AVIStreamRead will not read non-pcm/wma audio. Nor is there any way to supply fmod with .wma formatted audio, that I can see.

Movie class methods

play() - plays video

stop() - stops video

bind_texture() - binds the texture of the current frame being displayed
is_playing() - returns true if movie is playing, false otherwise

update() - updates the texture, and audio system. This needs to be called at the beginning of every cycle.

seek_forward() - fast forwards in increments of seekMilliseconds. seekMilliseconds is the second parameter of the Movie constructor, after the file name. The default is 1000 ms or 1 second.

seek_reverse() - seeks backwards in increments of seekMilliseconds.

seek_to_position() - seeks to a position specified in milliseconds from the start of the video.

mute() - sets volume to 0%

unmute() - sets volume to 100%

Here are the classes
Movie.hpp

#ifndef MOVIE_HPP
#define MOVIE_HPP

#ifdef _MSC_VER // use this to include specific libraries with msvc
#pragma comment(lib, "vfw32.lib")
#pragma comment(lib, "fmodex_vc.lib")
#endif // _MSC_VER

#include <Windows.h>
#include <Vfw.h>
#include <fmod.hpp>
#include <string>
#include <vector>
#include "MyTimer.hpp"

namespace bj
{
enum PLAY_STATE
{
PLAYING,
STOPPED
};

class Movie
{
public:
Movie(const std::string fileName_, DWORD seekInMilliseconds = 1000);
~Movie();
void play(); // start updating the texture and audio
void stop(); // Stop and cycle to beginning
void bind_texture();
bool is_playing()const; // Check play state
void update(); // must be called for every cycle
void seek_forward();
void seek_reverse();
void seek_to_position(DWORD positionInMs);
void mute();
void unmute();

private:
static int movieCount; // For VFW AVI library initialization
PLAY_STATE playState;

// For AVI itself
std::string fileName;
PAVIFILE aviFile;
AVIFILEINFO aviFileInfo;
bool hasAudio; // Has audio and or video
bool hasVideo;

// audio
WAVEFORMATEX waveFormat;
LONG audioBufferSize;
FMOD::System *audioSystem; // audio system
FMOD::Sound *audio;
FMOD::Channel *channel;
PAVISTREAM audioStream;
AVISTREAMINFO audioStreamInfo;
std::vector<char> audioBuffer;
long samplesPerSecond;

// video
unsigned int pbo;
int dataSize;
unsigned int texture; // Assumes opengl context has already been created
double nextFrame;
DWORD currentFrame;
DWORD lastFrame;
PAVISTREAM videoStream;
AVISTREAMINFO videoStreamInfo;
PGETFRAME frameDecompressor;
DWORD width; // width and height of video
DWORD height;
DWORD bytesPerPixel;
double mpf; // length for each frame to be displayed in milliseconds

// For play back
bj::Timer timer;
DWORD seekMilliseconds; // Advance or reverse playback position in milliseconds

void process_avi();
void process_audio();
void init_fmod();
void process_video();
void init_opengl();
void grab_frame();
};
}
#endif





Movie.cpp

#include "Movie.hpp"
#include <stdexcept>
#include <string>
#include <fmod.hpp>
#include <sources/glew.h>

// Initialization of static member
int bj::Movie::movieCount = 0;

using namespace bj;

Movie::Movie(const std::string fileName_, DWORD seekInMilliseconds):
playState(STOPPED),
fileName(fileName_),
aviFile(nullptr),
aviFileInfo(),
hasAudio(false),
hasVideo(false),
waveFormat(),
audioBufferSize(0),
audioSystem(nullptr),
audio(nullptr),
audioStream(nullptr),
audioStreamInfo(),
audioBuffer(),
samplesPerSecond(0),
pbo(0),
dataSize(0),
texture(0),
nextFrame(0),
currentFrame(0),
lastFrame(0),
videoStream(nullptr),
videoStreamInfo(),
frameDecompressor(nullptr),
width(0),
height(0),
bytesPerPixel(0),
mpf(0.0),
seekMilliseconds(seekInMilliseconds)
{
// Increment the movieCount. If movieCount == 1, this is the first time it's been initialized
// for this program. Initialize the AVI library
movieCount++;

if(1 == movieCount)
AVIFileInit();

process_avi();
process_audio();
init_fmod();
process_video();
init_opengl();
}

Movie::~Movie()
{
if(aviFile)
AVIFileClose(aviFile);

if(audioStream)
AVIStreamRelease(audioStream);

if(videoStream)
AVIStreamRelease(videoStream);

if(frameDecompressor)
AVIStreamGetFrameClose(frameDecompressor);

if(audio)
audio->release();

if(audioSystem)
audioSystem->close();

if(pbo)
glDeleteBuffers(1, &pbo);

if(texture)
glDeleteTextures(1, &texture);

movieCount--;
// If movieCount == 0, we're finished with the library. Deintialize the library
if(0 == movieCount)
AVIFileExit();
}

void Movie::process_avi()
{
HRESULT error = AVIFileOpenA(&aviFile, fileName.c_str(), OF_READ, nullptr);

if(error)
{
if(AVIERR_FILEOPEN == error)
throw(std::logic_error("Could not open file " + fileName));
else
throw(std::logic_error("Problem with opening file"));
}

AVIFileInfo(aviFile, &aviFileInfo, sizeof(aviFileInfo));
}
void Movie::process_audio()
{
// Check if there is a stream
LONGLONG error = AVIFileGetStream(aviFile, &audioStream, streamtypeAUDIO, 0);

if(AVIERR_NODATA == error)
{
// No audio stream in this file
return;
}
else
{
if(0 != error)
{
// Problem loading audio stream
throw(std::logic_error("Problem loading audio stream"));
}
}

// everything went fine getting the stream
AVIStreamInfo(audioStream, &audioStreamInfo, sizeof(AVISTREAMINFO));

samplesPerSecond = audioStreamInfo.dwRate / audioStreamInfo.dwScale;
float lengthInSeconds = (float)audioStreamInfo.dwLength * audioStreamInfo.dwScale /
audioStreamInfo.dwRate;
float bufferSize = lengthInSeconds * samplesPerSecond;

// Read the stream format

error = AVIStreamReadFormat(audioStream, AVIStreamStart(audioStream), nullptr, &audioBufferSize);

if(error)
{
throw(std::runtime_error("Could not read audio stream format"));
}

std::vector<unsigned char> audioChunk;
audioChunk.resize(audioBufferSize);
AVIStreamReadFormat(audioStream, AVIStreamStart(audioStream), &audioChunk.front(), &audioBufferSize);

memcpy(&waveFormat, &audioChunk.front(), audioChunk.size());

// Read the audio data
audioBufferSize = 0;
error = AVIStreamRead(audioStream, AVIStreamStart(audioStream), (LONG)bufferSize, nullptr, 0, &audioBufferSize, nullptr);

if(AVIERR_FILEREAD == error)
{
throw(std::runtime_error("File error"));
}

if(AVIERR_BUFFERTOOSMALL == error)
{
throw(std::runtime_error("Buffer too small"));
}

if(AVIERR_MEMORY == error)
{
throw(std::runtime_error("Not enough memory to complete operation"));
}

if(error)
{
throw(std::runtime_error("Problem reading stream data"));
}

audioBuffer.resize(audioBufferSize, 0);
LONG bytesRead = 0;
LONG samplesRead = 0;
error = AVIStreamRead(audioStream, AVIStreamStart(audioStream), (LONG)bufferSize, &audioBuffer.front(), audioBufferSize, &bytesRead , &samplesRead);

if(error)
{
throw(std::runtime_error("Problem reading stream data"));
}

}

void Movie::init_fmod()
{
// Check to make sure that there is audio
if(audioBuffer.empty())
return; // No audio

FMOD_RESULT result = FMOD_OK;

result = FMOD::System_Create(&audioSystem);

if(FMOD_OK != result)
{
throw(std::runtime_error("Could not create FMOD system"));
}

result = audioSystem->init(1, FMOD_INIT_NORMAL, nullptr);

if(result != FMOD_OK)
{
throw(std::runtime_error("Could not initialize FMOD system"));
}

// For now, PCM 16 is only supported
FMOD_CREATESOUNDEXINFO exinfo;

memset(&exinfo, 0, sizeof(FMOD_CREATESOUNDEXINFO));
exinfo.cbsize = sizeof(FMOD_CREATESOUNDEXINFO);
exinfo.length = audioBufferSize;
exinfo.format = FMOD_SOUND_FORMAT_PCM16; // Must specify for FMOD_OPENRAW
exinfo.defaultfrequency = waveFormat.nSamplesPerSec; // Must specify for FMOD_OPENRAW
exinfo.numchannels = waveFormat.nChannels; // Must specify for FMOD_OPENRAW

result = audioSystem->createSound(&audioBuffer.front(), FMOD_OPENRAW | FMOD_OPENMEMORY,
&exinfo, &audio);

// Get rid of excess memory
audioBuffer.swap(std::vector<char>());

if(FMOD_OK != result)
{
throw(std::runtime_error("Could not load sound"));
}

// success
hasAudio = true;
}

void Movie::process_video()
{
HRESULT error = AVIFileGetStream(aviFile, &videoStream, streamtypeVIDEO, 0);

if(error)
{
throw(std::runtime_error("Error getting video stream"));
}

// Get the stream info
error = AVIStreamInfo(videoStream, &videoStreamInfo, sizeof(videoStreamInfo));

if(error)
{
throw(std::runtime_error("Error getting video stream information"));
}

// Final frame
lastFrame = AVIStreamLength(videoStream);

// Time to display each frame
mpf = (double)AVIStreamSampleToTime(videoStream, lastFrame) / (double)lastFrame;

// Get decompressor
frameDecompressor = AVIStreamGetFrameOpen(videoStream, nullptr);

if(nullptr == frameDecompressor)
{
throw (std::runtime_error("Could not get decompressor"));
}
}

void Movie::init_opengl()
{
// Get video properties

LPBITMAPINFOHEADER lpbi = (LPBITMAPINFOHEADER)AVIStreamGetFrame(frameDecompressor, 0);

// width, height, bit count
width = lpbi->biWidth;
height = lpbi->biHeight;
bytesPerPixel = lpbi->biBitCount / 8;
dataSize = width * height * bytesPerPixel;

glGenBuffers(1, &pbo);
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo);
glBufferData(GL_PIXEL_UNPACK_BUFFER, dataSize, nullptr, GL_STREAM_DRAW);

glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

GLint format = bytesPerPixel == 3 ? GL_RGB : GL_RGBA;
glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, GL_BGR, GL_UNSIGNED_BYTE, nullptr);

// unbind
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
hasVideo = true;
}

void Movie::grab_frame()
{
static DWORD previousFrame = 0;

if((previousFrame != currentFrame) || (0 == currentFrame))
{
// Update the texture only if the previous frame does not equal the current frame or
// it's the first frame (frame #0)
LPBITMAPINFOHEADER lpbi = (LPBITMAPINFOHEADER)AVIStreamGetFrame(frameDecompressor, currentFrame);
// Get pointer to the data
char *data = (char*)lpbi + lpbi->biSize + (lpbi->biClrUsed * sizeof(RGBQUAD));

// Update the pbo and texture
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo);
glBufferSubData(GL_PIXEL_UNPACK_BUFFER, 0, dataSize, data);

previousFrame = currentFrame;
}
}

void Movie::play()
{
if(STOPPED == playState)
{
// Start audio first
audioSystem->playSound(FMOD_CHANNEL_FREE, audio, false, &channel);
timer.start();
playState = PLAYING;
}
}

void Movie::stop()
{
if(PLAYING == playState)
{
if(hasAudio)
channel->stop();

playState = STOPPED;

currentFrame = 0;
nextFrame = 0;
}
}

void Movie::bind_texture()
{
// TODO previousFrame
static DWORD previousFrame = 0;

if((previousFrame != currentFrame) || (0 == currentFrame))
{
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo);
glBindTexture(GL_TEXTURE_2D, texture);
GLint format = bytesPerPixel == 3 ? GL_RGB : GL_RGBA;
glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, GL_BGR, GL_UNSIGNED_BYTE, nullptr);
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
previousFrame = currentFrame;
}
else
{
glBindTexture(GL_TEXTURE_2D, texture);
}
}

bool Movie::is_playing()const
{
return (PLAYING == playState);
}

void Movie::update()
{
if(hasAudio)
audioSystem->update();

if(hasVideo && (PLAYING == playState))
{
nextFrame += timer.milliseconds();
currentFrame = (DWORD)(nextFrame / mpf);

if(currentFrame >= lastFrame)
{
currentFrame = 0;
nextFrame = 0;
playState = STOPPED;
}

grab_frame();
}
}

void Movie::seek_forward()
{
if(PLAYING == playState)
{
long sample = AVIStreamTimeToSample(videoStream, (LONG)nextFrame + seekMilliseconds);

nextFrame = AVIStreamSampleToTime(videoStream, sample);


// reset
timer.milliseconds();

if(hasAudio)
channel->setPosition((unsigned int)nextFrame, FMOD_TIMEUNIT_MS);

currentFrame = DWORD(nextFrame / mpf);


if(currentFrame <= 0 || (currentFrame >= lastFrame))
{
channel->stop();
currentFrame = 0;
playState = STOPPED;
nextFrame = 0;
}
}
}

void Movie::seek_reverse()
{
if(PLAYING == playState)
{
long sample = AVIStreamTimeToSample(videoStream, (LONG)nextFrame - seekMilliseconds);

if(-1 == sample)
{
// probably seeked before initial position
nextFrame = 0;
if(hasAudio)
channel->setPosition(0, FMOD_TIMEUNIT_MS);
timer.milliseconds();
return;
}

nextFrame = AVIStreamSampleToTime(videoStream, sample);
if(hasAudio)
channel->setPosition((unsigned int)nextFrame, FMOD_TIMEUNIT_MS);
// reset
timer.milliseconds();

currentFrame = DWORD(nextFrame / mpf);
}
}

void Movie::seek_to_position(DWORD positionInMs)
{
if(PLAYING == playState)
{
long sample = AVIStreamTimeToSample(videoStream, positionInMs);

if(-1 == sample)
{
// Error, do nothing or throw something
return;
}

nextFrame = AVIStreamSampleToTime(videoStream, sample);

if(hasAudio)
channel->setPosition((unsigned int)nextFrame, FMOD_TIMEUNIT_MS);
//reset
timer.milliseconds();

currentFrame = DWORD(nextFrame / mpf);
}
}

void Movie::mute()
{
if(PLAYING == playState && hasAudio)
{
channel->setMute(true);
}
}

void Movie::unmute()
{
if(PLAYING == playState && hasAudio)
{
channel->setMute(false);
}
}





MyTimer.hpp

#ifndef MYTIMER_HPP
#define MYTIMER_HPP

#include <Windows.h>

namespace bj
{

class Timer
{
public:
Timer();


void start(); // start or reset timer
double seconds(); // returns seconds since last time seconds or milliseconds has be called
double milliseconds(); // returns seconds since last time seconds or milliseconds has be called
double delta_from_start()const; // Returns

enum MODE {STOPPED, RUNNING, PAUSED};

private:
void set_state(MODE m);
MODE get_state()const;
LARGE_INTEGER startTime;
LARGE_INTEGER currentTime;
LARGE_INTEGER frequency;
MODE mode;

};
}





Timer.cpp

#include "MyTimer.hpp"

using namespace bj;

Timer::Timer():
mode(STOPPED)
{
QueryPerformanceFrequency(&frequency);
}

void Timer::start()
{
QueryPerformanceCounter(&currentTime);
startTime = currentTime;
set_state(RUNNING);
}



double Timer::seconds()
{
LARGE_INTEGER newTime;
QueryPerformanceCounter(&newTime);

double seconds = ((double)(newTime.QuadPart - currentTime.QuadPart)) / frequency.QuadPart;
currentTime = newTime;
return (seconds);
}

double Timer::milliseconds()
{
LARGE_INTEGER newTime;
double milliseconds;

QueryPerformanceCounter(&newTime);
milliseconds = (((double)(newTime.QuadPart - currentTime.QuadPart) / frequency.QuadPart)) * 1000.0;
currentTime = newTime;
return (milliseconds);
}

double Timer::delta_from_start()const
{
LARGE_INTEGER newTime;
QueryPerformanceCounter(&newTime);

return (((double)(newTime.QuadPart - startTime.QuadPart)) / frequency.QuadPart);
}

void Timer::set_state(MODE m)
{
mode = m;
}

Timer::MODE Timer::get_state()const
{
return (mode);
}





I hope this serves you well.

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      #shader vertex #version 330 core layout(location = 0) in vec4 aPos; layout(location = 1) in vec2 aTexCoord; out vec2 t_TexCoord; uniform mat4 u_MVP; void main() { gl_Position = u_MVP * aPos; t_TexCoord = aTexCoord; } #shader fragment #version 330 core out vec4 aColor; in vec2 t_TexCoord; uniform sampler2D u_Texture; void main() { aColor = texture(u_Texture, t_TexCoord); } Also i'm pretty sure that every time i'm hitting the up, down, left and right arrows on the keyboard, i'm changing the model Matrix of the Player and not the others.
       
      Window Class:
      #include "Window.h" #include <GL/glew.h> #include <GLFW/glfw3.h> #include "Error.h" #include "Renderer.h" #include "Scene.h" #include "Input.h" //Global Variables. int screen_width, screen_height; //On Window Resize. void OnWindowResize(GLFWwindow *window, int width, int height); //Implementation Structure. struct Window::Implementation { //GLFW Window. GLFWwindow *GLFW_window; //Renderer. Renderer *renderer; //Delta Time. double delta_time; //Frames Per Second. int fps; //Scene. Scene *scnene; //Input. Input *input; //Deconstructor. ~Implementation(); }; //Window Constructor. Window::Window(std::string title, int width, int height) { //Initializing width and height. screen_width = width; screen_height = height; //Create Pointer To Implementation. m_Impl = new Implementation(); //Try initializing GLFW. if (!glfwInit()) { std::cout << "GLFW could not be initialized!" << std::endl; std::cout << "Press ENTER to exit..." << std::endl; std::cin.get(); exit(-1); } //Setting up OpenGL Version 3.3 Core Profile. glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3); glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3); glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); /* Create a windowed mode window and its OpenGL context */ m_Impl->GLFW_window = glfwCreateWindow(width, height, title.c_str(), NULL, NULL); if (!m_Impl->GLFW_window) { std::cout << "GLFW could not create a window!" << std::endl; std::cout << "Press ENTER to exit..." << std::endl; std::cin.get(); glfwTerminate(); exit(-1); } /* Make the window's context current */ glfwMakeContextCurrent(m_Impl->GLFW_window); //Initialize GLEW. if(glewInit() != GLEW_OK) { std::cout << "GLEW could not be initialized!" << std::endl; std::cout << "Press ENTER to exit..." << std::endl; std::cin.get(); glfwTerminate(); exit(-1); } //Enabling Blending. GLCall(glEnable(GL_BLEND)); GLCall(glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)); //Setting the ViewPort. GLCall(glViewport(0, 0, width, height)); //**********Initializing Implementation**********// m_Impl->renderer = new Renderer(); m_Impl->delta_time = 0.0; m_Impl->fps = 0; m_Impl->input = new Input(this); //**********Initializing Implementation**********// //Set Frame Buffer Size Callback. glfwSetFramebufferSizeCallback(m_Impl->GLFW_window, OnWindowResize); } //Window Deconstructor. Window::~Window() { delete m_Impl; } //Window Main Loop. void Window::MainLoop() { //Time Variables. double start_time = 0, end_time = 0, old_time = 0, total_time = 0; //Frames Counter. int frames = 0; /* Loop until the user closes the window */ while (!glfwWindowShouldClose(m_Impl->GLFW_window)) { old_time = start_time; //Total time of previous frame. start_time = glfwGetTime(); //Current frame start time. //Calculate the Delta Time. m_Impl->delta_time = start_time - old_time; //Get Frames Per Second. if (total_time >= 1) { m_Impl->fps = frames; total_time = 0; frames = 0; } //Clearing The Screen. m_Impl->renderer->Clear(0, 0, 0); //Render The Scene. if (m_Impl->scnene != NULL) m_Impl->scnene->Render(this); //Updating the Screen. m_Impl->renderer->Update(m_Impl->GLFW_window); //Increasing frames counter. frames++; //End Time. end_time = glfwGetTime(); //Total time after the frame completed. total_time += end_time - start_time; } //Terminate GLFW. glfwTerminate(); } //Load Scene. void Window::LoadScene(Scene * scene) { //Set the scene. m_Impl->scnene = scene; } //Get Delta Time. double Window::GetDeltaTime() { return m_Impl->delta_time; } //Get FPS. int Window::GetFPS() { return m_Impl->fps; } //Get Width. int Window::GetWidth() { return screen_width; } //Get Height. int Window::GetHeight() { return screen_height; } //Get Input. Input * Window::GetInput() { return m_Impl->input; } Renderer * Window::GetRenderer() { return m_Impl->renderer; } GLFWwindow * Window::GetGLFWindow() { return m_Impl->GLFW_window; } //Implementation Deconstructor. Window::Implementation::~Implementation() { delete renderer; delete input; } //OnWindowResize void OnWindowResize(GLFWwindow *window, int width, int height) { screen_width = width; screen_height = height; //Updating the ViewPort. GLCall(glViewport(0, 0, width, height)); }  
      Brain Class
      #include "Brain.h" #include "Sprite.h" #include "Window.h" struct Brain::Implementation { //Just A Flag. bool started; //Window Pointer. Window *window; //Sprite Pointer. Sprite *sprite; }; Brain::Brain(Window *window, Sprite *sprite) { //Create Pointer To Implementation. m_Impl = new Implementation(); //Initialize Implementation. m_Impl->started = true; m_Impl->window = window; m_Impl->sprite = sprite; } Brain::~Brain() { //Delete Pointer To Implementation. delete m_Impl; } void Brain::Start() { } void Brain::Update() { } Window * Brain::GetWindow() { return m_Impl->window; } Sprite * Brain::GetSprite() { return m_Impl->sprite; } bool Brain::GetStart() { return m_Impl->started; } void Brain::SetStart(bool value) { m_Impl->started = value; } Script Class (Its a Brain Subclass!!!)
      #include "Script.h" Script::Script(Window *window, Sprite *sprite) : Brain(window, sprite) { } Script::~Script() { } void Script::Start() { std::cout << "Game Started!" << std::endl; } void Script::Update() { Input *input = this->GetWindow()->GetInput(); Sprite *sp = this->GetSprite(); //Move this sprite. this->GetSprite()->Move(200 * this->GetWindow()->GetDeltaTime(), input->GetKeyDown("left"), input->GetKeyDown("right"), input->GetKeyDown("up"), input->GetKeyDown("down")); std::cout << sp->GetTag().c_str() << ".x = " << sp->GetPos()->x << ", " << sp->GetTag().c_str() << ".y = " << sp->GetPos()->y << std::endl; }  
      Main:
      #include "SpaceShooterEngine.h" #include "Script.h" int main() { Window w("title", 600,600); Scene *scene = new Scene(); Sprite *player = new Sprite("Resources/Images/player.png", "Player", 100,100); Sprite *other = new Sprite("Resources/Images/cherno.png", "Other", 400, 100); Sprite *other2 = new Sprite("Resources/Images/cherno.png", "Other", 300, 400); Brain *brain = new Script(&w, player); player->AddBrain(brain); scene->AddSprite(player); scene->AddSprite(other); scene->AddSprite(other2); w.LoadScene(scene); w.MainLoop(); return 0; }  
       
      I literally can't find what is wrong. If you need more code, ask me to post it. I will also attach all the source files.
      Brain.cpp
      Error.cpp
      IndexBuffer.cpp
      Input.cpp
      Renderer.cpp
      Scene.cpp
      Shader.cpp
      Sprite.cpp
      Texture.cpp
      VertexArray.cpp
      VertexBuffer.cpp
      VertexBufferLayout.cpp
      Window.cpp
      Brain.h
      Error.h
      IndexBuffer.h
      Input.h
      Renderer.h
      Scene.h
      Shader.h
      SpaceShooterEngine.h
      Sprite.h
      Texture.h
      VertexArray.h
      VertexBuffer.h
      VertexBufferLayout.h
      Window.h
    • By Cristian Decu
      Hello fellow programmers,
      For a couple of days now i've decided to build my own planet renderer just to see how floating point precision issues
      can be tackled. As you probably imagine, i've quickly faced FPP issues when trying to render absurdly large planets.
       
      I have used the classical quadtree LOD approach;
      I've generated my grids with 33 vertices, (x: -1 to 1, y: -1 to 1, z = 0).
      Each grid is managed by a TerrainNode class that, depending on the side it represents (top, bottom, left right, front, back),
      creates a special rotation-translation matrix that moves and rotates the grid away from the origin so that when i finally
      normalize all the vertices on my vertex shader i can get a perfect sphere.
      T = glm::translate(glm::dmat4(1.0), glm::dvec3(0.0, 0.0, 1.0)); R = glm::rotate(glm::dmat4(1.0), glm::radians(180.0), glm::dvec3(1.0, 0.0, 0.0)); sides[0] = new TerrainNode(1.0, radius, T * R, glm::dvec2(0.0, 0.0), new TerrainTile(1.0, SIDE_FRONT)); T = glm::translate(glm::dmat4(1.0), glm::dvec3(0.0, 0.0, -1.0)); R = glm::rotate(glm::dmat4(1.0), glm::radians(0.0), glm::dvec3(1.0, 0.0, 0.0)); sides[1] = new TerrainNode(1.0, radius, R * T, glm::dvec2(0.0, 0.0), new TerrainTile(1.0, SIDE_BACK)); // So on and so forth for the rest of the sides As you can see, for the front side grid, i rotate it 180 degrees to make it face the camera and push it towards the eye;
      the back side is handled almost the same way only that i don't need to rotate it but simply push it away from the eye.
      The same technique is applied for the rest of the faces (obviously, with the proper rotations / translations).
      The matrix that result from the multiplication of R and T (in that particular order) is send to my vertex shader as `r_Grid'.
      // spherify vec3 V = normalize((r_Grid * vec4(r_Vertex, 1.0)).xyz); gl_Position = r_ModelViewProjection * vec4(V, 1.0); The `r_ModelViewProjection' matrix is generated on the CPU in this manner.
      // No the most efficient way, but it works. glm::dmat4 Camera::getMatrix() { // Create the view matrix // Roll, Yaw and Pitch are all quaternions. glm::dmat4 View = glm::toMat4(Roll) * glm::toMat4(Pitch) * glm::toMat4(Yaw); // The model matrix is generated by translating in the oposite direction of the camera. glm::dmat4 Model = glm::translate(glm::dmat4(1.0), -Position); // Projection = glm::perspective(fovY, aspect, zNear, zFar); // zNear = 0.1, zFar = 1.0995116e12 return Projection * View * Model; } I managed to get rid of z-fighting by using a technique called Logarithmic Depth Buffer described in this article; it works amazingly well, no z-fighting at all, at least not visible.
      Each frame i'm rendering each node by sending the generated matrices this way.
      // set the r_ModelViewProjection uniform // Sneak in the mRadiusMatrix which is a matrix that contains the radius of my planet. Shader::setUniform(0, Camera::getInstance()->getMatrix() * mRadiusMatrix); // set the r_Grid matrix uniform i created earlier. Shader::setUniform(1, r_Grid); grid->render(); My planet's radius is around 6400000.0 units, absurdly large, but that's what i really want to achieve;
      Everything works well, the node's split and merge as you'd expect, however whenever i get close to the surface
      of the planet the rounding errors start to kick in giving me that lovely stairs effect.
      I've read that if i could render each grid relative to the camera i could get better precision on the surface, effectively
      getting rid of those rounding errors.
       
      My question is how can i achieve this relative to camera rendering in my scenario here?
      I know that i have to do most of the work on the CPU with double, and that's exactly what i'm doing.
      I only use double on the CPU side where i also do most of the matrix multiplications.
      As you can see from my vertex shader i only do the usual r_ModelViewProjection * (some vertex coords).
       
      Thank you for your suggestions!
       
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