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OpenGL Textures

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Hey, I am pretty new to OpenGL, but not Graphics Programming in general. Anyway, I have been making my way to OpenGL from SDL. I have been following some tutorials on OpenGL and I have been doing great I think. Anyway, I have gotten to the texture mapping tutorial. Well, the problem is my texture will not show up. I can not figure out what is wrong. It should display an error message if it can not load up the texture. It never does, so I am not sure. Here is my code. It uses GLut also.
#include <iostream>
//include glut
#include <gl/glut.h>
#include <il\il.h>
#include <il\ilu.h>	
#include <il\ilut.h>

//render function
void RenderScene();
//resize function
void Resize(int w, int h);
//init function
void Init();
//get normal keys function
void GetNormalKeys(unsigned char key, int x, int y);
//get the special keys now
void GetSpecialKeys(int key, int x, int y);
//load up the textures
int LoadGLTextures();

//Create enough storage space for one texture
GLuint texture[1];	

void main(int argc, char **argv) 
{
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
	glutInitWindowPosition(100,100);
	glutInitWindowSize(320,320);
	glutCreateWindow("GLut");
	glutDisplayFunc(RenderScene);
	glutReshapeFunc(Resize);
	glutIdleFunc(RenderScene);
	glutKeyboardFunc(GetNormalKeys);
	glutSpecialFunc(GetSpecialKeys);
	glutMainLoop();
}

void RenderScene()
{
	glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
	glLoadIdentity();
	glTranslatef(-1.f, 0.0f, -6.0f);
	glBindTexture(GL_TEXTURE_2D, texture[0]);
	
	glBegin(GL_QUADS);
		// Front Face
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
		// Back Face
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
		// Top Face
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
		// Bottom Face
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
		// Right face
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);
		// Left Face
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);
	glEnd();
	glutSwapBuffers();
}

void Resize(int w, int h)
{
	// Prevent a divide by zero, when window is too short
	// (you cant make a window of zero width).
	if(h == 0)
		h = 1;

	float ratio = 1.0* w / h;

	// Reset the coordinate system before modifying
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	
	// Set the viewport to be the entire window
	glViewport(0, 0, w, h);

	// Set the correct perspective.
	gluPerspective(45,ratio,1,1000);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	gluLookAt(0.0, 0.0, 5.0, 0.0, 0.0, -1.0, 0.0f, 1.0f, 0.0f);
}


void Init()
{
	//enable depth testing
	glEnable(GL_DEPTH_TEST);
	//smooth for the shade model
	glShadeModel(GL_SMOOTH);
	//clear background
	glClearColor(0.0f, 0.0f, 0.0f, 0.5f);
	glClearDepth(1.0f);	
	glEnable(GL_DEPTH_TEST);
	glDepthFunc(GL_LEQUAL);	
	glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
	if(!LoadGLTextures())
	{
		std::cout<<"could not load the textures"<<std::endl;
	}
	glEnable(GL_TEXTURE_2D);
}


void GetNormalKeys(unsigned char key, int x, int y)
{
	if(key==27)
	{
		exit(0);
	}
}

void GetSpecialKeys(int key, int x, int y)
{
	switch(key)
	{
	case GLUT_KEY_F1: glutFullScreen(); break;
	}
}

int LoadGLTextures()
{
	ILuint ImgId;										// The Image Name

	ilGenImages(1, &ImgId);								// Generate Image Name
	ilBindImage(ImgId);									// Bind Image Name to Be Current
	if (!ilLoadImage((ILstring)"texture.bmp")) {				// Load the Bitmap and Check for Errors
		ilDeleteImages(1, &ImgId);						// If Could Not Load, Delete Image
		return FALSE;									//  and Return False
	}

	texture[0] = ilutGLBindTexImage();					// Send the Image to OpenGL
	ilDeleteImages(1, &ImgId);							// Delete the Image Name, As GL Has a Copy
	
	return true;	
}

So, can someone please help me figure this out? Thanks to all who help! Chad.

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Are you sure that your texture is power of 2 (64, 128, 256)?

And if it is that you are saving it as rgb, a couple days ago I couldn't get my height map to load, I found out I was saving it as greyscale :b

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yes, it is a power of 2. The image size is 128X128. I will check on how I am saving it. I did have to save something as a grayscale the other day, although I don't think I am now. Let me open photoshop up and check.


Yep, saving it as a RGB. I also just converted it to a jpeg, to see if that worked and it didn't. Still didn't show up.


Anyone else? This is making no since to me.

Thanks to all who help!!


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Two things try using this


glFrontFace(GL_CCW);

//or
glFrontFace(GL_CW);

//and try this

gluLookAt(0.0, 0.0, -10.0, 0.0, 0.0, 0.0, 0.0f, 1.0f, 0.0f);





Off the top of my head I am betting its the gluLookAt() try that first. But I am assuming you left the default winding order to CCW so try CW your order for your vertices maybe backwards...

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I tried everything you said, and still nothing. I am beginning to think that my error checking is wrong, and it's not loading it up period. Ever since I posted my source, I have even added DevIL error checking and still no errors have been outputted.

While I still look at some things, can someone maybe compile my source, to see if it is the source or if I am just being stupid with the texture? Any help is appreciated!


Thanks,
Chad!

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First of all, sorry for the double post. I have done more thinking on this, and reading more and more things, and I have finally gotten it closer now. First of all...now the application gets a runtime error. Yes, I said I was closer. I am closer because the application breaks at the ilLoadImage function. When it breaks, I get this as the run time error (not sure if it's runtime or not, but it does it at runtime, so yeah...):


First-chance exception at 0x00000000 in OpenGL.exe: 0xC0000005: Access violation reading location 0x00000000.
Unhandled exception at 0x00000000 in OpenGL.exe: 0xC0000005: Access violation reading location 0x00000000.



It is giving me that, and it is breaking in this function:


void LoadGLTexture()
{
ILuint ImgId; // The Image Name

ilGenImages(1, &ImgId); // Generate Image Name
ilBindImage(ImgId); // Bind Image Name to Be Current
ilLoadImage("texture.jpg");
std::cout<<Error<<std::endl;
texture= ilutGLBindTexImage(); // Send the Image to OpenGL
ilDeleteImages(1, &ImgId); // Delete the Image Name, As GL Has a Copy
}




Anyone see anything wrong?

Here is my new code. I have changed some stuff from the first one. So, here is the new code:


#include <iostream>
//include glut
#include <gl/glut.h>
#include <il\il.h>
#include <il\ilu.h>
#include <il\ilut.h>

//render function
void RenderScene();
//resize function
void Resize(int w, int h);
//init function
void Init();
//get normal keys function
void GetNormalKeys(unsigned char key, int x, int y);
//get the special keys now
void GetSpecialKeys(int key, int x, int y);
//load up the textures
void LoadGLTexture();

//Create enough storage space for one texture
GLuint texture;

ILenum Error;

//rotation variables
float xR=.12;
float yR=.12;
float zR=.12;

void main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
Init();
glutInitWindowPosition(100,100);
glutInitWindowSize(320,320);
glutCreateWindow("GLut");
glutDisplayFunc(RenderScene);
glutReshapeFunc(Resize);
glutIdleFunc(RenderScene);
glutKeyboardFunc(GetNormalKeys);
glutSpecialFunc(GetSpecialKeys);
glutMainLoop();
}

void RenderScene()
{
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
gluLookAt(0.0, 0.0, -10.0, 0.0, 0.0, 0.0, 0.0f, 1.0f, 0.0f);
glFrontFace(GL_CW);
glRotatef(xR,1.0f,0.0f,0.0f);
glRotatef(yR,0.0f,1.0f,0.0f);
glRotatef(zR,0.0f,0.0f,1.0f);
glBindTexture(GL_TEXTURE_2D, texture);

glBegin(GL_QUADS);
// Front Face
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
// Back Face
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
// Top Face
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, 1.0f, 1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f);
// Bottom Face
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
// Right face
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f);
// Left Face
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
glEnd();
xR+=0.1f;
yR+=0.1f;
zR+=0.1f;
glutSwapBuffers();
}

void Resize(int w, int h)
{
// Prevent a divide by zero, when window is too short
// (you cant make a window of zero width).
if(h == 0)
h = 1;

float ratio = 1.0* w / h;

// Reset the coordinate system before modifying
glMatrixMode(GL_PROJECTION);
glLoadIdentity();

// Set the viewport to be the entire window
glViewport(0, 0, w, h);

// Set the correct perspective.
gluPerspective(45,ratio,1,1000);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(0.0, 0.0, 5.0, 0.0, 0.0, -1.0, 0.0f, 1.0f, 0.0f);
}


void Init()
{
glEnable(GL_TEXTURE_2D);
ilutRenderer(ILUT_OPENGL);
Error = ilGetError();
LoadGLTexture();
//enable depth testing
glEnable(GL_DEPTH_TEST);
//smooth for the shade model
glShadeModel(GL_SMOOTH);
//clear background
glClearColor(0.0f, 0.0f, 0.0f, 0.5f);
glClearDepth(1.0f);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
}


void GetNormalKeys(unsigned char key, int x, int y)
{
if(key==27)
{
exit(0);
}
}

void GetSpecialKeys(int key, int x, int y)
{
switch(key)
{
case GLUT_KEY_F1: glutFullScreen(); break;
}
}

void LoadGLTexture()
{
ILuint ImgId; // The Image Name

ilGenImages(1, &ImgId); // Generate Image Name
ilBindImage(ImgId); // Bind Image Name to Be Current
ilLoadImage("texture.jpg");
std::cout<<Error<<std::endl;
texture= ilutGLBindTexImage(); // Send the Image to OpenGL
ilDeleteImages(1, &ImgId); // Delete the Image Name, As GL Has a Copy
}




Anyone have any ideas? This is really confusing me.

Thanks to all who help!

Chad.

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      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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