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OpenGL configrations of OPENGL on LINUX_

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Hi all. from what i see linux doesn't wahe directly opengl support. so i read somewhere sdl does this work. some questions about linux. i installed sdl by hoping to use it for opengl but g++ doesn't see it. is there some command line options to getting info about configrations. i tryed to open some binaries but they shows empty forms. Or is there any other choice for using opengl on linux.

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OpenGL is absolutely possible on Linux

[google] = "OpenGL Linux"

It depends what you mean by "supported". Windows doesn't directly support OpenGL either, it's the graphics card drivers and hardware that support OpenGL, not the operating system.

As for "doesn't see it" it's probably because you didn't set up your include and lib paths properly. For that either do a "man g++" or look online for how to set up g++ and makefiles and whatnot.

-me

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Linux is just the kernel, you need supporting progs for everything else. For example X for the windowing system. X also provides OpenGL support. Many vendor drivers tie into X to provide great hardware accelerated OpenGL support for example the NVidia drivers (gives full access to what you would have on Windows).

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thanks .
so some notes on web says mesa using software rendering if this is correct how can i able to use direct/indirect hardware access on opengl like windows's opengl library.

isn't there any man who can cower how to use device op codes.?
or isn nwidia like wendowrs making it like a secret?
because like you guys says this is hardware.
but why big part of linux developers are forced to use software rendering
instead of direct accees of vga's options .?
or am i missed dont know something about this..?

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Hardware OpenGL works fine in Linux in any modern version of Linux with any modern video card. No software rendering necessary or vendor specific code necessary. Do you have the right drivers for your card? Try typing glxinfo into the command line and post the result. It should tell you if you have direct (hardware) rendering capability. Next thing you want to try is to cruise over to nehe.gamedev.net and download one of their opengl lessons for linux.

This one is for Linux + SDL:
http://nehe.gamedev.net/data/lessons/linuxsdl/lesson05.tar.gz

This one is for Linux + GLX:
http://nehe.gamedev.net/data/lessons/linuxglx/lesson05.tar.gz

SDL is easier to work with and its cross platform, so I recommend it for dev work. However, it requires that you have the SDL libraries installed. (SDL-dev package I believe in Ubuntu). The GLX version should run without SDL or anything other than the normal X windows system (which I'm sure you have).

Try running make in the directories that you extract them to. This should build the binary executable you need to run them. They should build without any issues if things are set up properly.

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Quote:
Original post by Erkokite
Do you have the right drivers for your card? Try typing glxinfo into the command line and post the result. It should tell you if you have direct (hardware) rendering capability.

it looks like this supports some opengl extensions.
but i tryed executebles from codesamples.com for GLX and sdl GLX
one of them works but its realy slow like 4~fps/sec.[teapot sample]
driver says its mesa so is this mean my system uses software rendering
or isnt there any way to turn to harware based rendering system.?
thanks...
also is someone knows where can i find GLX libraries/headers


name of display: :0.0
display: :0 screen: 0
direct rendering: No
server glx vendor string: SGI
server glx version string: 1.2
server glx extensions:
GLX_ARB_multisample, GLX_EXT_visual_info, GLX_EXT_visual_rating,
GLX_EXT_import_context, GLX_EXT_texture_from_pixmap, GLX_OML_swap_method,
GLX_SGI_make_current_read, GLX_SGIS_multisample, GLX_SGIX_hyperpipe,
GLX_SGIX_swap_barrier, GLX_SGIX_fbconfig, GLX_MESA_copy_sub_buffer
client glx vendor string: SGI
client glx version string: 1.4
client glx extensions:
GLX_ARB_get_proc_address, GLX_ARB_multisample, GLX_EXT_import_context,
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_MESA_allocate_memory,
GLX_MESA_copy_sub_buffer, GLX_MESA_swap_control,
GLX_MESA_swap_frame_usage, GLX_OML_swap_method, GLX_OML_sync_control,
GLX_SGI_make_current_read, GLX_SGI_swap_control, GLX_SGI_video_sync,
GLX_SGIS_multisample, GLX_SGIX_fbconfig, GLX_SGIX_pbuffer,
GLX_SGIX_visual_select_group, GLX_EXT_texture_from_pixmap
GLX version: 1.2
GLX extensions:
GLX_ARB_get_proc_address, GLX_ARB_multisample, GLX_EXT_import_context,
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_MESA_copy_sub_buffer,
GLX_OML_swap_method, GLX_SGI_make_current_read, GLX_SGIS_multisample,
GLX_SGIX_fbconfig, GLX_EXT_texture_from_pixmap
OpenGL vendor string: Mesa project: www.mesa3d.org
OpenGL renderer string: Mesa GLX Indirect
OpenGL version string: 1.2 (1.5 Mesa 6.5.1)
OpenGL extensions:
GL_ARB_depth_texture, GL_ARB_imaging, GL_ARB_multitexture,
GL_ARB_point_parameters, GL_ARB_point_sprite, GL_ARB_shadow,
GL_ARB_shadow_ambient, GL_ARB_texture_border_clamp,
GL_ARB_texture_cube_map, GL_ARB_texture_env_add,
GL_ARB_texture_env_combine, GL_ARB_texture_env_crossbar,
GL_ARB_texture_env_dot3, GL_ARB_texture_mirrored_repeat,
GL_ARB_texture_non_power_of_two, GL_ARB_texture_rectangle,
GL_ARB_transpose_matrix, GL_ARB_window_pos, GL_EXT_abgr, GL_EXT_bgra,
GL_EXT_blend_color, GL_EXT_blend_func_separate, GL_EXT_blend_logic_op,
GL_EXT_blend_minmax, GL_EXT_blend_subtract, GL_EXT_clip_volume_hint,
GL_EXT_copy_texture, GL_EXT_draw_range_elements, GL_EXT_fog_coord,
GL_EXT_framebuffer_object, GL_EXT_multi_draw_arrays, GL_EXT_packed_pixels,
GL_EXT_point_parameters, GL_EXT_polygon_offset, GL_EXT_rescale_normal,
GL_EXT_secondary_color, GL_EXT_separate_specular_color,
GL_EXT_shadow_funcs, GL_EXT_stencil_wrap, GL_EXT_subtexture,
GL_EXT_texture, GL_EXT_texture3D, GL_EXT_texture_edge_clamp,
GL_EXT_texture_env_add, GL_EXT_texture_env_combine,
GL_EXT_texture_env_dot3, GL_EXT_texture_lod_bias, GL_EXT_texture_object,
GL_EXT_texture_rectangle, GL_EXT_vertex_array, GL_APPLE_packed_pixels,
GL_ATI_texture_env_combine3, GL_ATI_texture_mirror_once,
GL_ATIX_texture_env_combine3, GL_IBM_texture_mirrored_repeat,
GL_INGR_blend_func_separate, GL_MESA_pack_invert, GL_MESA_ycbcr_texture,
GL_NV_blend_square, GL_NV_point_sprite, GL_NV_texgen_reflection,
GL_NV_texture_rectangle, GL_SGIS_generate_mipmap,
GL_SGIS_texture_border_clamp, GL_SGIS_texture_edge_clamp,
GL_SGIS_texture_lod, GL_SGIX_depth_texture, GL_SGIX_shadow,
GL_SGIX_shadow_ambient, GL_SUN_multi_draw_arrays
glu version: 1.3
glu extensions:
GLU_EXT_nurbs_tessellator, GLU_EXT_object_space_tess

visual x bf lv rg d st colorbuffer ax dp st accumbuffer ms cav
id dep cl sp sz l ci b ro r g b a bf th cl r g b a ns b eat
----------------------------------------------------------------------
0x23 16 tc 0 16 0 r y . 5 6 5 0 0 16 0 0 0 0 0 0 0 None
0x24 16 tc 0 16 0 r y . 5 6 5 0 0 16 8 16 16 16 0 0 0 None
0x25 16 tc 0 24 0 r y . 5 6 5 8 0 16 8 16 16 16 16 0 0 None
0x26 16 tc 0 24 0 r . . 5 6 5 8 0 16 8 16 16 16 16 0 0 None
0x27 16 dc 0 16 0 r y . 5 6 5 0 0 16 0 0 0 0 0 0 0 None
0x28 16 dc 0 16 0 r y . 5 6 5 0 0 16 8 16 16 16 0 0 0 None
0x29 16 dc 0 24 0 r y . 5 6 5 8 0 16 8 16 16 16 16 0 0 None
0x2a 16 dc 0 24 0 r . . 5 6 5 8 0 16 8 16 16 16 16 0 0 None

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Quote:
Original post by RSC_x
Quote:
Original post by Erkokite
Do you have the right drivers for your card? Try typing glxinfo into the command line and post the result. It should tell you if you have direct (hardware) rendering capability.

it looks like this supports some opengl extensions.
but i tryed executebles from codesamples.com for GLX and sdl GLX
one of them works but its realy slow like 4~fps/sec.[teapot sample]
driver says its mesa so is this mean my system uses software rendering
or isnt there any way to turn to harware based rendering system.?

Mesa3D _is_ the OpenGL implementation on X11, so it doesn't mean that Mesa3D only does software rendering. All you need to do to enable hardware acceleration is use the appropriate driver for your card and tell X11 to use that driver, which by looking at the output of glxinfo, I think you're already doing.
So, I don't see why it should be slow.
I develop OpenGL programs on Linux and they work rather well.

You may have issues with certain drivers depending upon how you've built the kernel, but that is rare and usually don't cause OpenGL to work slowly.

Quote:
Original post by RSC_xalso is someone knows where can i find GLX libraries/headers
Depends upon what distribution you're using. You'll find gl and xorg headers in the repositories of most distributions.
For example, I use Gentoo Linux, so the headers are installed when I install xorg.
On Debian, you'll probably need to install the package called libmesa-dev and some package which contains the headers for xorg.

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RSC_x,
X Window system allows 3D acceleration through DRI (Direct Rendering Infrastructure), but your glxinfo reports the direct rendering is not enabled yet.

I don't know what video card you have, but you can enable DRI by editing xorg.conf. (I am guessing you are also using X.Org.) You need to load the DRI module and to set usage permission in the config file.

Section "Module"
Load "glx"
Load "dri"
...
EndSection

Section "DRI"
Mode 0666
EndSection


Restart X (init 3; then, init 5), then run glxinfo again. If "direct rendering" shows Yes, then the hardware acceleration is enabled on your system.

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Quote:
Original post by songho
RSC_x,
X Window system allows 3D acceleration through DRI (Direct Rendering Infrastructure), but your glxinfo reports the direct rendering is not enabled yet.

I don't know what video card you have, but you can enable DRI by editing xorg.conf. (I am guessing you are also using X.Org.) You need to load the DRI module and to set usage permission in the config file.
*** Source Snippet Removed ***
Restart X (init 3; then, init 5), then run glxinfo again. If "direct rendering" shows Yes, then the hardware acceleration is enabled on your system.


this is part of xorg.conf.ini and some other similar files.
so is this means my nvidia card does not hawe support for DRI.?
is this just nvidia/debain spesific.?
bacause above bug report means its not available for nvidia.?
or is there any linux wersion which supports DRI on nvidia.?
sorry for long questions.
and thanks for information.
//---------------
Section "Module"
# Comments: see http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=346408
Load "dbe" # Double Buffering Extension, very important.
Load "dri" # This shouldn't be available choice if user has selected driver vga, vesa or nv.
Load "glx" # GLX Extension.
Load "freetype" # Freetype fonts.
Load "type1" # Type 1 fonts
//-----------------

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Quote:
Original post by RSC_x
this is part of xorg.conf.ini and some other similar files.
so is this means my nvidia card does not hawe support for DRI.?

Nvidia's proprietary drivers, which you need to get 3D support on Nvidia cards, don't use DRI - they have their own way of accessing the hardware.

The module section of my xorg.conf is:

Section "Module"
Load "dbe"
Load "extmod"
Load "type1"
Load "freetype"
Load "glx"
EndSection

If you haven't already, go to www.nvidia.com and download the latest version of the linux drivers and install them using the instructions in provided. Note: there is a good chance it will want to compile a kernel module so you'll need the kernel development headers (the kernel-devel package) installed on your system. The installation utility will tell you if you haven't got that package installed, do the compilation and take care of changing your config files as necessary.

For reference, the output from glxinfo on my system starts with:

name of display: :0.0
display: :0 screen: 0
direct rendering: Yes
server glx vendor string: NVIDIA Corporation
server glx version string: 1.4
server glx extensions:
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_SGIX_fbconfig,
GLX_SGIX_pbuffer, GLX_SGI_video_sync, GLX_SGI_swap_control,
GLX_EXT_texture_from_pixmap, GLX_ARB_multisample, GLX_NV_float_buffer,
GLX_ARB_fbconfig_float, GLX_EXT_framebuffer_sRGB
client glx vendor string: NVIDIA Corporation
client glx version string: 1.4
client glx extensions:
GLX_ARB_get_proc_address, GLX_ARB_multisample, GLX_EXT_visual_info,
GLX_EXT_visual_rating, GLX_EXT_import_context, GLX_SGI_video_sync,
GLX_NV_swap_group, GLX_NV_video_out, GLX_SGIX_fbconfig, GLX_SGIX_pbuffer,
GLX_SGI_swap_control, GLX_NV_float_buffer, GLX_ARB_fbconfig_float,
GLX_EXT_fbconfig_packed_float, GLX_EXT_texture_from_pixmap,
GLX_EXT_framebuffer_sRGB
GLX version: 1.3
GLX extensions:
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_SGIX_fbconfig,
GLX_SGIX_pbuffer, GLX_SGI_video_sync, GLX_SGI_swap_control,
GLX_EXT_texture_from_pixmap, GLX_ARB_multisample, GLX_NV_float_buffer,
GLX_ARB_fbconfig_float, GLX_EXT_framebuffer_sRGB,
GLX_ARB_get_proc_address
OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: GeForce 8600 GTS/PCI/SSE2
OpenGL version string: 2.1.1 NVIDIA 100.14.03
OpenGL extensions:
GL_ARB_color_buffer_float, GL_ARB_depth_texture, GL_ARB_draw_buffers,
GL_ARB_fragment_program, GL_ARB_fragment_program_shadow,
GL_ARB_fragment_shader, GL_ARB_half_float_pixel, GL_ARB_imaging,
GL_ARB_multisample, GL_ARB_multitexture, GL_ARB_occlusion_query,
GL_ARB_pixel_buffer_object, GL_ARB_point_parameters, GL_ARB_point_sprite,
GL_ARB_shadow, GL_ARB_shader_objects, GL_ARB_shading_language_100,

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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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