OpenGL is a graphics standard and API which targets the desktop and workstation markets. It is designed to be easy to accelerate with dedicated computer hardware, and hence most implementations give greatly improved performance over traditional software rendering. Currently, OpenGL is used for ...

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Most efficient way to draw vertex with OpenGL

I am writing an OpenGL 3D game. There will be tons of triangles for terrain and objects in use. I am studying from the OpenGL official guide and the first presented method is to call a function ...
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856 views

Does one need normals for a strictly 2d Game?

I'm starting to learn OpenGL by creating a pure 2D game. I have to decide on the format of the Vertices. Do I need a normal component? Or is this for a 2d component not needed? My gut feeling says I ...
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4answers
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glsl demo suggestions?

In a lot of places I interviewed recently, I have been asked many a times if I have worked with shaders. Even though, I have read and understand the pipeline, the answer to that question has been no. ...
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474 views

How wise is this multithreading architecture?

I'm rewriting a game engine I wrote in an attempt to parallelize as much as possible. I'm considering making properties which may be accessed from multiple threads all use accessors which use boost ...
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2answers
298 views

Must I worry about quad-based rendering in real world scenarios?

Most of the time in the first chapters of a random book about rasterization and rendering techniques, I find some phrases about a triangle-based rendering system and a quad-based one. I have never ...
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Missing features from WebGL and OpenGL ES

I've started using WebGL and am pleased with how easy it is to leverage my OpenGL (and by extension OpenGL ES) experience. However, my understanding is as follows: OpenGL ES is a subset of OpenGL ...
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3answers
847 views

What is the contents of the buffer *after* a call to glSwapBuffers()?

(SDL_GL_SwapBuffers() in particular) When you have drawn a scene, and you call swap-buffers, it is routine to then glClear() the scene before drawing anything; if you don't clear, what is the ...
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First time shadow mapping problems

I have implemented basic shadow mapping for the first time in OpenGL using shaders and I'm facing some problems. Below you can see an example of my rendered scene: The process of the shadow mapping ...
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How can I orbit a camera about it's target point?

I'm drawing a scene where the camera freely moves about the universe. The camera class keeps track of the view (or look at) point, the position of the camera, and the up vector. These vectors/points ...
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How do I change a sprite's color?

In my rhythm game, I have a note object which can be of a different color depending on the note chart. I could use a sprite sheet with all the different color variations I use, but I would prefer to ...
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Is there a way to blur objects in a 2d game with OpenGL without using shaders?

Is there a nice way in OpenGL to blur objects without using shaders? Currently, I'm accomplishing blur by rendering the object slightly up, down, left, right, and the four diagonals from its original ...
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Most efficient way to draw large number of the same objects, but with different transforms

I'd like to draw a large number (multiple thousands) of simple meshes (each maybe... a maximum of 50 triangles, but even that is a very large upper bound), all of which are exactly the same. As a ...
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481 views

Best practices with Vertices in Open GL

What is the best practice in regards to storing vertex data in Open GL? I.e: struct VertexColored { public: GLfloat position[]; GLfloat normal[]; byte colours[]; } ...
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615 views

Large vertex buffer vs multiple draw calls

I'm just getting started with OpenGL, and I'm attempting to use it to create a 2D game. In this game, I have a hexagonal grid made up of a very large variety of differently-colored hexagons. As a ...
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1answer
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Should I give each character its own VBO or should I batch them into a single VBO?

I'm making a 3D first person game. Should I give each character its own VBO or should I batch all characters into a single VBO? What are the pros/cons?
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Why should I not use glTools/glut when developing complete applications?

I've started learning how to use OpenGL a while back, using the OpenGL SuperBible, Fifth Edition, and I've had people arguing about the fact that the book doesn't really teach how to use OpenGL but ...
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3answers
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OpenGL - Stack overflow if I do, Stack underflow if I don't!

I'm in a multimedia class in college, and we're "learning" OpenGL as part of the class. I'm trying to figure out how the OpenGL camera vs. modelview works, and so I found this example. I'm trying to ...
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GLSL Shader - Change Hue/Saturation/Brightness

I'm trying to change the hue of an image using a GLSL fragment shader. I want to achieve something similar to Photoshop's Hue/Saturation Adjustment layer. In the following image you can see what I've ...
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Fastest way to draw small particles in opengl?

Quick question : Which is the fastest method to render a large array of 4x4/8x8 particles in opengl ? Currently i spend 2triangles for each one but i think that its slow so i would really like to know ...
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462 views

What types of effects or shaders would you teach in a rendering class? [closed]

I am looking for a list of topics that would be fun to learn and not too complicated to implement with a prototyping tool like FX Composer or Rendermonkey for an intermediate class of real-time ...
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3answers
2k views

Optimizing Octree Rendering

Say I have an octree and at a certain level I store VBOs in that octree. I know the dimensions of of the nodes that own the vbo so I can do basic frustum culling. That works nicely because everything ...
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1answer
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Interleaving Arrays in OpenGL

In my pursuit to write code that matches todays OpenGL standards I have found that I am completely clueless about interleaving arrays. I've tried and debugged just about everywhere I can think of but ...
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699 views

Do I really have to write my own optimized model format?

So I'm a brand new noob to the world of game dev and I'm starting off by trying to write my own game using C++ and openGL. I'm getting into loading models etc and while searching around for "the best ...
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SDL2 with OpenGL — weird results, what's wrong?

I'm porting an app to iOS, and therefore need to upgrade it to SDL2 from SDL1.2 (so far I'm testing it as an on OS X desktop app only). However, when running the code with SDL2, I'm getting weird ...
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208 views

Can applications using old versions of Opengl still run on newer cards?

OpenGl 3.0 and up has a quite big difference from the older versions like OpenGl 2.x and opengl 1.x in terms of implementation, does that mean applications which are written with the old versions of ...
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How do I apply skeletal animation from a .x (Direct X) file?

Using the .x format to export a model from Blender, I can load a mesh, armature and animation. I have no problems generating the mesh and viewing models in game. Additionally, I have animations and ...
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What causes some computers to have no or slow OpenGL, and how to fix it?

I am using Java with JOGL to create OpenGL enhanced 2D graphics. The graphics operations I use are nothing fancy, and should be supported by almost any recent graphics card. For example, my game ...
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1answer
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GLSL, all in one or many shader programs?

I am doing some 3D demos using OpenGL and I noticed that GLSL is somewhat "limited" (or is it just me?). Anyway I have many different types of materials. Some materials have ambient and diffuse color, ...
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2answers
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Sorting objects before rendering

I'm trying to implement a scene graph and in all the articles i've come across there is talk about object sorting. So you'd sort your objects by "material" for example. Now untill i sat down and ...
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1answer
904 views

How can I organize render and transformation data in a scalable fashion?

I am writing for OpenGL 2.0 and in the future porting to OpenGL ES 2.0. I only use VBOs and shaders (no immediate mode, no vertex arrays). I already have working solutions, they just... feel wrong. ...
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2answers
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Frustum Culling with VBOs

I have terrain being rendered in my project using VBOs in OpenGL. I would like to apply some Frustum Culling but have no idea how to access each polygon as its drawn to check if it is in view. I think ...
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3answers
193 views

Terrain & Multi-Texturing

I'm using OpenGL (Version 4.4) (and C++ if that matters). I've created a terrain renderer, the terrain is stored as a 3D scalar field (isosurface/voxels). It uses a slightly modified version of ...
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2answers
409 views

Deferred tiled shading, tile frusta calculation in OpenGL

I'm trying to do deferred tiled shading in OpenGL using the compute shader but I have hit a snag when trying to create the frustum for each tile. I'm using AMD's Forward+ demo (written in D3D) as a ...
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2answers
819 views

How would I setup fog to follow a players coordinates?

I'm wondering if its possible to setup a fog to a player's coordinates (where there is fog around the player to make it more third-person) the main reason I ask this is because I have my player more ...
7
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4answers
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OpenGL 2D Rasterization Sub-Pixel Translations

I have a tile based 2D engine where the projection matrix is an orthographic view of the world without any scaling applied. Thus: one pixel texture is drawn on the screen in the same size. That all ...
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5answers
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OpenGL vs OGRE : Which is the best for beginner? [closed]

I am interested in getting into game development and posses good C/C++ programming skills. I have tried OGRE before, and I am curious whether I should learn either OGRE or OpenGL as a starting point. ...
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3answers
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What features does D3D have that OpenGL does not (and vice versa)?

Are there any feature comparisons on Direct3D 11 and the newest OpenGL versions? Well, simply put, Direct3D 11 introduced three main features (taken from Wikipedia): Tessellation Multithreaded ...
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4answers
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What is the purpose of glScissor?

I know that it is more efficient than stencil test, but am I right assuming that the same functionality could be achieved using projection transformations with viewport?
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4answers
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2D Platformer Collision Handling

I am trying to create a 2D platformer (Mario-type) game and I am some having some issues with handling collisions properly. I am writing this game in C++, using SDL for input, image loading, font ...
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3answers
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Draw contour around object in Opengl

I need to draw contour around 2d objects in 3d space. I tried drawing lines around object(+points to fill the gap), but due to line width, some part of it(~50%) was covering object. I tried to use ...
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3answers
860 views

Understanding how to create/use textures for games when limited by power of two sizes

I have some questions about the creating graphics for a game. As an example. I want to create a motorbike. (1pixel = 1centimeter) So my motorbike will have 200 width and 150 height. (200x150) But the ...
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2answers
3k views

OpenGL ES 2.0: Using VBOs?

OpenGL VBOs (vertex buffer objects) have been developed to improve performance of OpenGL (OpenGL ES 2.0 in my case). The logic is that with the help of VBOs, the data does not need to be copied from ...
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1answer
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Why is Minecraft's default resolution (seemingly) non-standard?

Background: I'm writing some articles on Minecraft in an attempt to introduce 10-year olds to development through modding. I know very little about the game itself, though :) I'm trying to understand ...
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3answers
459 views

shadowing billboards

I have a lot of billboarded 3D spheres (they have a heightmap so work properly with depth and penetration; although each is made of just a quad (with slight distortion), they look and feel and are ...
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4answers
2k views

Order independent transparency in particle system

I'm writing a particle system and would like to find a trick to achieve proper alpha blending without sorting particles because: Each particle is a point sprite in a single mesh and I can't use ...
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3answers
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How do I implement occluded lighting in a block-based 2D game?

I want to have 2D lighting that can be blocked by in-game objects. My game has a top-down view and all game objects are described by rectangles. Let's say I have a 10x10 world and I place a light at ...
6
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1answer
229 views

GLSL vertex shaders with movements vs vertex off the screen

If i have a vertex shader that manage some movements and variations about the position of some vertex in my OpenGL context, OpenGL is smart enough to just run this shader on only the vertex visible on ...
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4answers
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Spell Effects/Shaders

I want to be able to achieve spell effects that cause a fragmenting/discoloring effect on the sprite. The first couple seconds of this video http://www.youtube.com/watch?v=HNCFh7mkvuc shows what I ...
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2answers
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How do you determine which object/surface the user's pointing at with lwjgl?

Title pretty much says it all. I'm working on a simple 'lets get used to lwjgl' project involving manipulation of a rubik's cube, and I can't figure out how to tell which side/square the user's ...
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2answers
613 views

OpenGL or OpenGL ES

What should I learn? OpenGL 4.1 or OpenGL ES 2.0? I will be developing desktop applications using Qt but I may start developing mobile applications in a few months, too. I don't know anything about ...