Jump to content
  • Advertisement

Archived

This topic is now archived and is closed to further replies.

Crypthor

OpenGL OpenGL vs DirectX

This topic is 6646 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

Just interesting there is a reason to support OpenGL? As war is follow, i headr many people that''s like OGL or DX. Some people says that OGL slowly dying, and DX is the future of 3D. How do you people think, OGL ( exactly OGL ) will be supported for a long time ( 5-10 years for example ) The hardware providers will support acceleration on their 3D cards for OGL in future ? Or, again Micro$oft with his DX win a "battle" ?

Share this post


Link to post
Share on other sites
Advertisement
It''s going to be OpenGL in the future, and not Direct3D, as far as I''m concerned.
Microsoft has just ripped the OpenGL interface anyway, for their stuff, if I remember the discussions correctly.

Share this post


Link to post
Share on other sites
I think you can''t say anything for sure about that right now. MS more or less controls it both (that is because OpenGL drivers for Windows comes from MS themselves).

Keep in mind though that you can''t compare OpenGL with DirectX since DX is a whole suit of gamedev components and OpenGL is only graphics. A more valid question would be the fight between Direct3D and OpenGL.

============================
Daniel Netz, Sentinel Design
"I'm not stupid, I'm from Sweden" - Unknown

Share this post


Link to post
Share on other sites
If you don''t want to support M$ (for the reason you want) or if you are planning multi-platform strategy, then OpenGL is the API to support.
Linux is coming, BeOS is free, there''s no reason why you shouldn''t use OpenGL to choose a windows only not very well design API (DirectX).
OpenGL has been thought and proved very usefull, Direct3D is a copy and is windows specific, need I say more ?

OpenGL means : "Open Graphioc Library", so I defintely prefer an open architecture rather than a M$ controlled one.
(Or anyone controlled.)
If you look around, every card as OpenGL miniGL and more and more comes with an OpenGL ICD.
nVidia works much with OpenGL, PowerVR are faster with OpenGL...

OpenGL is the most interesting API out there.
Direct3D had become more interesting, since Dreamcast use it, but it''s not enough to use it.


-* Sounds, music and story makes the difference between good and great games *-

Share this post


Link to post
Share on other sites
D3D is Windows only, OpenGL is portable. That in itself is reason enough to -know- OpenGL, even if you don''t use it that much. As leading companies like Corel and iD are saying, you have to consider Linux. Not to mention Macs, BeOS or any other new platform that may gain popularity.

Share this post


Link to post
Share on other sites
No offense. But I''m tired of hearing people say DirectX sucks because it''s MS. That''s a bad reason to say anything sucks. Just cause of the company that makes it.

Share this post


Link to post
Share on other sites
Guest Anonymous Poster
I am partial to OpenGL. I started to learn DirectX and it just wasn''t my thing. Learned OpenGL and love it. You usually want a 3d accelerator if you are going to code opengl though.

Share this post


Link to post
Share on other sites
Directx has all components in there, graphics, input, network sound, and programming interface for all of them is very similar, so basically you''ll learn it only once. All that you need, whereas opengl has only graphics (there''s that OpenAL thing, but its nonexistent at this stage). And for some reason, i dont have big hopes on Linux becoming wildly popular all of a sudden. Im not a windows fan (8bit 80 machines like Z80 are the BEST!), but its gonna remain the biggest audience forcouple of years at least, and theres that X-Box announced as well, which is going to use Directx as its API.
So if you have any plans of showing the world your accomplishments in the future, go with DX.

-kertropp

Share this post


Link to post
Share on other sites
don''t choose either... one can''t tell where anything will be in 5 years, so if you want to be prepared for anything, learn both API''s

OGL is easy to learn. Direct3d is significantly more difficult, but both are easy to use once you know them.

*oof*

Share this post


Link to post
Share on other sites
Sorry, using Direct3D is risky, since Microsoft may be broken by antitrust law. Confusion and inability of management may suddenly kill usability of Direct3D.

Moreover, Microsoft does not seem to learn from the past. It continues its monopoly-like illegal strategy: using its monopoly advantage for other markets. I wonder if Microsoft even recognize this strategy is illegal. This keeps the risk higher and higher,,,.

OpenGL is safer.

Kate

Edited by - kate on 3/14/00 9:41:46 AM

Share this post


Link to post
Share on other sites

  • Advertisement
  • Advertisement
  • Popular Tags

  • Popular Now

  • Advertisement
  • Similar Content

    • By mmmax3d
      Hi everyone,
      I would need some assistance from anyone who has a similar experience
      or a nice idea!
      I have created a skybox (as cube) and now I need to add a floor/ground.
      The skybox is created from cubemap and initially it was infinite.
      Now it is finite with a specific size. The floor is a quad in the middle
      of the skybox, like a horizon.
      I have two problems:
      When moving the skybox upwards or downwards, I need to
      sample from points even above the horizon while sampling
      from the botton at the same time.  I am trying to create a seamless blending of the texture
      at the points of the horizon, when the quad is connected
      to the skybox. However, I get skew effects. Does anybody has done sth similar?
      Is there any good practice?
      Thanks everyone!
    • By mmmax3d
      Hi everyone,
      I would need some assistance from anyone who has a similar experience
      or a nice idea!
      I have created a skybox (as cube) and now I need to add a floor/ground.
      The skybox is created from cubemap and initially it was infinite.
      Now it is finite with a specific size. The floor is a quad in the middle
      of the skybox, like a horizon.
      I have two problems:
      When moving the skybox upwards or downwards, I need to
      sample from points even above the horizon while sampling
      from the botton at the same time.  I am trying to create a seamless blending of the texture
      at the points of the horizon, when the quad is connected
      to the skybox. However, I get skew effects. Does anybody has done sth similar?
      Is there any good practice?
      Thanks everyone!
    • By iArtist93
      I'm trying to implement PBR into my simple OpenGL renderer and trying to use multiple lighting passes, I'm using one pass per light for rendering as follow:
      1- First pass = depth
      2- Second pass = ambient
      3- [3 .. n] for all the lights in the scene.
      I'm using the blending function glBlendFunc(GL_ONE, GL_ONE) for passes [3..n], and i'm doing a Gamma Correction at the end of each fragment shader.
      But i still have a problem with the output image it just looks noisy specially when i'm using texture maps.
      Is there anything wrong with those steps or is there any improvement to this process?
    • By babaliaris
      Hello Everyone!
      I'm learning openGL, and currently i'm making a simple 2D game engine to test what I've learn so far.  In order to not say to much, i made a video in which i'm showing you the behavior of the rendering.
      Video: 
       
      What i was expecting to happen, was the player moving around. When i render only the player, he moves as i would expect. When i add a second Sprite object, instead of the Player, this new sprite object is moving and finally if i add a third Sprite object the third one is moving. And the weird think is that i'm transforming the Vertices of the Player so why the transformation is being applied somewhere else?
       
      Take a look at my code:
      Sprite Class
      (You mostly need to see the Constructor, the Render Method and the Move Method)
      #include "Brain.h" #include <glm/gtc/matrix_transform.hpp> #include <vector> struct Sprite::Implementation { //Position. struct pos pos; //Tag. std::string tag; //Texture. Texture *texture; //Model matrix. glm::mat4 model; //Vertex Array Object. VertexArray *vao; //Vertex Buffer Object. VertexBuffer *vbo; //Layout. VertexBufferLayout *layout; //Index Buffer Object. IndexBuffer *ibo; //Shader. Shader *program; //Brains. std::vector<Brain *> brains; //Deconstructor. ~Implementation(); }; Sprite::Sprite(std::string image_path, std::string tag, float x, float y) { //Create Pointer To Implementaion. m_Impl = new Implementation(); //Set the Position of the Sprite object. m_Impl->pos.x = x; m_Impl->pos.y = y; //Set the tag. m_Impl->tag = tag; //Create The Texture. m_Impl->texture = new Texture(image_path); //Initialize the model Matrix. m_Impl->model = glm::mat4(1.0f); //Get the Width and the Height of the Texture. int width = m_Impl->texture->GetWidth(); int height = m_Impl->texture->GetHeight(); //Create the Verticies. float verticies[] = { //Positions //Texture Coordinates. x, y, 0.0f, 0.0f, x + width, y, 1.0f, 0.0f, x + width, y + height, 1.0f, 1.0f, x, y + height, 0.0f, 1.0f }; //Create the Indicies. unsigned int indicies[] = { 0, 1, 2, 2, 3, 0 }; //Create Vertex Array. m_Impl->vao = new VertexArray(); //Create the Vertex Buffer. m_Impl->vbo = new VertexBuffer((void *)verticies, sizeof(verticies)); //Create The Layout. m_Impl->layout = new VertexBufferLayout(); m_Impl->layout->PushFloat(2); m_Impl->layout->PushFloat(2); m_Impl->vao->AddBuffer(m_Impl->vbo, m_Impl->layout); //Create the Index Buffer. m_Impl->ibo = new IndexBuffer(indicies, 6); //Create the new shader. m_Impl->program = new Shader("Shaders/SpriteShader.shader"); } //Render. void Sprite::Render(Window * window) { //Create the projection Matrix based on the current window width and height. glm::mat4 proj = glm::ortho(0.0f, (float)window->GetWidth(), 0.0f, (float)window->GetHeight(), -1.0f, 1.0f); //Set the MVP Uniform. m_Impl->program->setUniformMat4f("u_MVP", proj * m_Impl->model); //Run All The Brains (Scripts) of this game object (sprite). for (unsigned int i = 0; i < m_Impl->brains.size(); i++) { //Get Current Brain. Brain *brain = m_Impl->brains[i]; //Call the start function only once! if (brain->GetStart()) { brain->SetStart(false); brain->Start(); } //Call the update function every frame. brain->Update(); } //Render. window->GetRenderer()->Draw(m_Impl->vao, m_Impl->ibo, m_Impl->texture, m_Impl->program); } void Sprite::Move(float speed, bool left, bool right, bool up, bool down) { if (left) { m_Impl->pos.x -= speed; m_Impl->model = glm::translate(m_Impl->model, glm::vec3(-speed, 0, 0)); } if (right) { m_Impl->pos.x += speed; m_Impl->model = glm::translate(m_Impl->model, glm::vec3(speed, 0, 0)); } if (up) { m_Impl->pos.y += speed; m_Impl->model = glm::translate(m_Impl->model, glm::vec3(0, speed, 0)); } if (down) { m_Impl->pos.y -= speed; m_Impl->model = glm::translate(m_Impl->model, glm::vec3(0, -speed, 0)); } } void Sprite::AddBrain(Brain * brain) { //Push back the brain object. m_Impl->brains.push_back(brain); } pos *Sprite::GetPos() { return &m_Impl->pos; } std::string Sprite::GetTag() { return m_Impl->tag; } int Sprite::GetWidth() { return m_Impl->texture->GetWidth(); } int Sprite::GetHeight() { return m_Impl->texture->GetHeight(); } Sprite::~Sprite() { delete m_Impl; } //Implementation Deconstructor. Sprite::Implementation::~Implementation() { delete texture; delete vao; delete vbo; delete layout; delete ibo; delete program; }  
      Renderer Class
      #include "Renderer.h" #include "Error.h" Renderer::Renderer() { } Renderer::~Renderer() { } void Renderer::Draw(VertexArray * vao, IndexBuffer * ibo, Texture *texture, Shader * program) { vao->Bind(); ibo->Bind(); program->Bind(); if (texture != NULL) texture->Bind(); GLCall(glDrawElements(GL_TRIANGLES, ibo->GetCount(), GL_UNSIGNED_INT, NULL)); } void Renderer::Clear(float r, float g, float b) { GLCall(glClearColor(r, g, b, 1.0)); GLCall(glClear(GL_COLOR_BUFFER_BIT)); } void Renderer::Update(GLFWwindow *window) { /* Swap front and back buffers */ glfwSwapBuffers(window); /* Poll for and process events */ glfwPollEvents(); }  
      Shader Code
      #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!
       
  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

Participate in the game development conversation and more when you create an account on GameDev.net!

Sign me up!