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OpenGL GLSL confusion

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Edit: Rewrote this first post, since noone were interested. I will be trying to get a grip of GLSL in another way instead. So, the first thing I've got to ask is how this texturing thing works. I've got shader designer 1.6 at it's working with these shaders:
// vertex shader
varying vec3 lightDir, normal;

void main(){
	normal = normalize(gl_NormalMatrix * gl_Normal);
	lightDir = normalize(vec3(gl_LightSource[0].position));

	gl_TexCoord[0] = gl_MultiTexCoord0;
	
	gl_Position = ftransform();
}


// fragment shader
varying vec3 lightDir, normal;
uniform sampler2D tex;

void main(){
	vec3 ct, cf;
	vec4 texel;
	float intensity, at, af;
	
	intensity = max(dot(lightDir, normalize(normal)), 0.0);
	
	cf = intensity * (gl_FrontMaterial.diffuse).rgb + gl_FrontMaterial.ambient.rgb;
	af = gl_FrontMaterial.diffuse.a;
	
	texel = texture2D(tex, gl_TexCoord[0].st);
	ct = texel.rgb;
	at = texel.a;
	
	gl_FragColor = vec4(ct * cf, at * af) * 2;
}

But it doesn't work in my OpenGL application. I create my texture like this:
glGenTextures(1, &texture[0].texID);
glBindTexture(GL_TEXTURE_2D, texture[0].texID);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, 3,texture[0].width, texture[0].height,
		0, GL_RGB, GL_UNSIGNED_BYTE, texture[0].imageData);

Then I bind it where I create my globe, like this (and this is where I also create the uniform)
glTranslatef(potX, potY, 0.0f);

glActiveTexture(GL_TEXTURE0);
int tex_loc = glGetUniformLocation(shader.id(), "tex");
glUniform1i(tex_loc, 0);
glBindTexture(GL_TEXTURE_2D, texture[0].texID);

glRotatef(-65.0f, 0, 1, 0);
glCallList(globe);

I have to say, that it doesn't really seem to matter if I initialize my shaders or not. No errors in my program. It compiles and shows my globe and the text and the star field behind it. The light is there (can't really tell if I'm using fragment lighting or not). I also do not see the big deal with shaders if I have to do what I've allways done and then create a shader to do it again? I've been using the Lighthouse2D and Swiftless tutorials to get to this point. Here's to hoping someone might want to give a hand :) Thanks, Marcus Axelsson [Edited by - tre on December 9, 2009 10:52:22 AM]

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Sorry for bumping this. But the OP has been totally edited and the thread has a new direction :)

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I don't see that you even activated the shader program, that might be you're problem: glUseProgramObjectARB(ShaderProgram);

Are you using some sort of class to manage shaders? The problem could be with something associated to that. Did you forget to instantiate/configure anything?

Also, create a 'varying vec2 TexCoord' instead. Then in the vertex shader assign it: TexCoord = gl_MultiTexCoord0.st, in the fragment shader you then access TexCoord instead. I can't remember off the top of my head the reason for it, but that's the recommended approach in the OpenGL spec. I'll have to look it up later and ref.

Oh, don't forget to disable the shader afterwards, or use a new one.
glUseProgramObjectARB(0);

[Edited by - npeqp on December 9, 2009 11:07:10 AM]

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Quote:
Original post by npeqp
I don't see that you even activated the shader program, that might be you're problem: glUseProgramObjectARB(ShaderProgram);

Are you using some sort of class to manage shaders? The problem could be with something associated to that. Did you forget to instantiate/configure anything?

Also, create a 'varying vec2 TexCoord' instead. Then in the vertex shader assign it: TexCoord = gl_MultiTexCoord0.st, in the fragment shader you then access TexCoord instead. I can't remember off the top of my head the reason for it, but that's the recommended approach in the OpenGL spec. I'll have to look it up later and ref.

Oh, don't forget to disable the shader afterwards, or use a new one.
glUseProgramObjectARB(0);


I use a shader class:
// snippet from "shaderProcessor.h"
class Shader {
public:
Shader();
Shader(const char *vsFile, const char *fsFile);
~Shader();

void init(const char *vsFile, const char *fsFile);

void bind();
void unbind();

unsigned int id();
private:
unsigned int shader_id;
unsigned int shader_vp;
unsigned int shader_fp;
};


Which I use to create my shaders.
// snippet from "shaderProcessor.cpp"
...
void Shader::init(const char *vsFile, const char *fsFile){
shader_vp = glCreateShader(GL_VERTEX_SHADER);
shader_fp = glCreateShader(GL_FRAGMENT_SHADER);

const char *vsText = textFileRead(vsFile);
const char *fsText = textFileRead(fsFile);

if(vsText == NULL || fsText == NULL){
// felmeddelande
return;
}

glShaderSource(shader_vp, 1, &vsText, 0);
glShaderSource(shader_fp, 1, &fsText, 0);

glCompileShader(shader_vp);
glCompileShader(shader_fp);

shader_id = glCreateProgram();
glAttachShader(shader_id, shader_fp);
glAttachShader(shader_id, shader_vp);
glLinkProgram(shader_id);
}
...

I use glUseProgram(0) to unbind shaders.

Then to initialize a shader I call shader.init("test.vert", "test.frag");.

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How do you set up the display list? (what calls are in it etc)
I would suggest starting with a minimal triangle and no lighting or anything, to make it easier to troubleshoot. I don't really understand what the problem is, is it just that the texture isn't showing, but the rest seems fine?
You should also check the result of glCompileShader, as it can fail if there's a typo or something in the shader code.

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Quote:
Original post by Erik Rufelt
How do you set up the display list? (what calls are in it etc)
I would suggest starting with a minimal triangle and no lighting or anything, to make it easier to troubleshoot. I don't really understand what the problem is, is it just that the texture isn't showing, but the rest seems fine?
You should also check the result of glCompileShader, as it can fail if there's a typo or something in the shader code.


The problem is that no matter what I do in the shader I'm not seeing any results. This row in the vertex shader: texCoord = gl_MultiTexCoord0.st * 0; should result in me not having a texture at all (as in Shader Designer 1.6). But the texture shows anyway.
This makes me wonder if I'm using any shaders at all.

This is how I set up my display lists
void buildLists(void){
Vertices vGlobe, vStars;
vGlobe.vPos("models/globe2.obj");
vStars.vPos("models/starmodel.obj");

int i = 0;

globe = glGenLists(1);
glNewList(globe, GL_COMPILE);
glBegin(GL_TRIANGLES);
glColor3f(0.0f, 1.0f, 0.0f);
for(i = 0; i < (int)vGlobe.f_v1.size(); i++){
glNormal3f(vGlobe.vNx[vGlobe.f_n1], vGlobe.vNy[vGlobe.f_n1], vGlobe.vNz[vGlobe.f_n1]);
glTexCoord3f(vGlobe.vTu[vGlobe.f_vt1], vGlobe.vTv[vGlobe.f_vt1], vGlobe.vTw[vGlobe.f_vt1]);
glVertex3f(vGlobe.vX[vGlobe.f_v1], vGlobe.vY[vGlobe.f_v1], vGlobe.vZ[vGlobe.f_v1]);

glNormal3f(vGlobe.vNx[vGlobe.f_n2], vGlobe.vNy[vGlobe.f_n2], vGlobe.vNz[vGlobe.f_n2]);
glTexCoord3f(vGlobe.vTu[vGlobe.f_vt2], vGlobe.vTv[vGlobe.f_vt2], vGlobe.vTw[vGlobe.f_vt2]);
glVertex3f(vGlobe.vX[vGlobe.f_v2], vGlobe.vY[vGlobe.f_v2], vGlobe.vZ[vGlobe.f_v2]);

glNormal3f(vGlobe.vNx[vGlobe.f_n3], vGlobe.vNy[vGlobe.f_n3], vGlobe.vNz[vGlobe.f_n3]);
glTexCoord3f(vGlobe.vTu[vGlobe.f_vt3], vGlobe.vTv[vGlobe.f_vt3], vGlobe.vTw[vGlobe.f_vt3]);
glVertex3f(vGlobe.vX[vGlobe.f_v3], vGlobe.vY[vGlobe.f_v3], vGlobe.vZ[vGlobe.f_v3]);
}
glEnd();
glEndList();

stars = glGenLists(1);
glNewList(stars, GL_COMPILE);
glBegin(GL_TRIANGLES);
for(i = 0; i < (int)vStars.f_v1.size(); i++){
glNormal3f(vStars.vNx[vStars.f_n1], vStars.vNy[vStars.f_n1], vStars.vNz[vStars.f_n1]);
glTexCoord3f(vStars.vTu[vStars.f_vt1], vStars.vTv[vStars.f_vt1], vStars.vTw[vStars.f_vt1]);
glVertex3f(vStars.vX[vStars.f_v1], vStars.vY[vStars.f_v1], vStars.vZ[vStars.f_v1]);

glNormal3f(vStars.vNx[vStars.f_n2], vStars.vNy[vStars.f_n2], vStars.vNz[vStars.f_n2]);
glTexCoord3f(vStars.vTu[vStars.f_vt2], vStars.vTv[vStars.f_vt2], vStars.vTw[vStars.f_vt2]);
glVertex3f(vStars.vX[vStars.f_v2], vStars.vY[vStars.f_v2], vStars.vZ[vStars.f_v2]);

glNormal3f(vStars.vNx[vStars.f_n3], vStars.vNy[vStars.f_n3], vStars.vNz[vStars.f_n3]);
glTexCoord3f(vStars.vTu[vStars.f_vt3], vStars.vTv[vStars.f_vt3], vStars.vTw[vStars.f_vt3]);
glVertex3f(vStars.vX[vStars.f_v3], vStars.vY[vStars.f_v3], vStars.vZ[vStars.f_v3]);
}
glEnd();
glEndList();
}






EDIT:
Allright, this was me showing how blind and stupid a person can be :)
I had forgot that I had created a folder for my shaders and forgot to add that to the shader initialization. Sorry about that.

Now my next step would be to add one texture to the dark side of the globe and one to the light side.

[Edited by - tre on December 9, 2009 12:17:57 PM]

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Step two (blending two textures, one in light one in dark) is allmost done. I've got it working in ShaderDesigner.
The "day" texture won't work.

Here's my globe function:
void drawGlobe(float size, int slices){
glTranslatef(potX, potY, 0.0f);

glBindTexture(GL_TEXTURE_2D, texture[0].texID);
glActiveTexture(GL_TEXTURE0);
int tex_loc0 = glGetUniformLocation(shader.id(), "TextureUnit0");
glUniform1i(tex_loc0, 0);

glBindTexture(GL_TEXTURE_2D, texture[2].texID);
glActiveTexture(GL_TEXTURE0);
int tex_loc1 = glGetUniformLocation(shader.id(), "TextureUnit1");
glUniform1i(tex_loc1, 1);


glRotatef(-65.0f, 0, 1, 0);
glCallList(globe);
}


And the shaders:
// vertex shader
varying vec3 lightDir, normal;
varying vec2 texCoord;

void main(){
normal = normalize(gl_NormalMatrix * gl_Normal);
lightDir = normalize(vec3(gl_LightSource[0].position));

gl_TexCoord[0] = gl_MultiTexCoord0;
gl_TexCoord[1] = gl_MultiTexCoord0;

gl_Position = ftransform();
}

// fragment shader
varying vec3 lightDir, normal;
varying vec2 texCoord;
uniform sampler2D TextureUnit0;
uniform sampler2D TextureUnit1;

void main(){
vec3 ct, cf, c;
vec4 texel;
float intensity, at, af, a;

intensity = max(dot(lightDir, normalize(normal)), 0.0);

cf = intensity * (gl_FrontMaterial.diffuse).rgb +
gl_FrontMaterial.ambient.rgb;;
af = gl_FrontMaterial.diffuse.a;

texel = texture2D(TextureUnit0, vec2(gl_TexCoord[0].st));

ct = texel.rgb;
at = texel.a;

c = cf * ct;
a = af * at;

float coef = smoothstep(1.0, 0.0, intensity);
c += coef * vec3(texture2D(TextureUnit1, vec2(gl_TexCoord[0].st)));

gl_FragColor = vec4(c, a);
}


I'm using the Lighthouse3D Multitexture tutorial for this. I think the problem is in my globe function. I can't seem to be able to push the correct texture unit to the shader.
The shaders work great in ShaderDesigner.

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Allright. Since I'm done with this now I'm doing this new post instead of editing.

The day texture and the night texture blends nice together. It might need some tweaking to get it looking just right.

I just used the Lighthouse tutorial (Link) for those who want the same effect.
The problem was getting my OpenGL program connecting and passing information correctly to the shader and also excluding/reactivating the right texture for the star map.

glActiveTexture(GL_TEXTURE1); to activate the second texture unit and then reverting back to glActiveTexture(GL_TEXTURE0); before doing the star map. And everything works.


My next step is to create some sort of atmosphere for the globe. I'm thinking about creating a new shader for this. Is this the right way to go?
At the moment I'm just activating the fragment light + globe lights shader in initialization and then unbinding/binding where it's needed. So this time I thought I'd create a new shader in the same way and do a second set of unbind/bind.
Or should I try to squeeze this new shader information into the current shader?

And how do I go about creating an atmosphere? Should I create a new sphere around the globe and add the shader to that?
I'm not trying to make a physically correct atmosphere, though. Just something that can fool the user to believe in an atmosphere.

Later I'd like to add animating clouds. Can I create some sort of animated perlin noise shader? What would the most efficient way to create clouds be?

Hoping for some guidiance here :)

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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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