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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1answer
349 views

Getting started to OpenGL - little question

Im starting to learn opengl, and after 2 days, searching and trying hard, i finally installed all the libraries i need (lol). So, I'm following this tutorial, and it says to use glfwOpenWindowHint ...
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votes
3answers
985 views

Started game development no idea of computer graphics. Should I learn tools or concepts? [closed]

I am in 6th semester of my Computer science bachelor degree program, Working as Intern in a start up company. I started game development using AndEngine, things are going good because I have good hold ...
5
votes
3answers
5k views

Should I use Game Engines to learn to make 3D games? [closed]

HI i am a software engineering student in his second-last year. I am proficient with C,C++,C# and java programming languages, and being a student of engineering I have studied calculus, vectors etc ...
5
votes
4answers
8k views

GLM: Euler Angles to Quaternion

I hope you know GL Mathematics (GLM) because I've got a problem, I can not break: I have a set of Eular Angles and I need to perform smooth interpolation between them. The best way is converting them ...
5
votes
2answers
2k views

What is the order-less rendering technique that allows partial transparency?

I've seen somewhere rendering technique that allows order-less rendering of partially transparent sprites/objects. Though I can't remember what the technique is called, so I'm having trouble Googling ...
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votes
3answers
740 views

game models that stand in grass

The open source game Glest has models that feel detached from the ground that they sit on because of the hard edges. In real life, grass is not flat! What are the options and recommendations for ...
5
votes
3answers
914 views

What is the purpose of indices in 3D rendering?

Suppose you were creating a 3D cube in OpenGL. You implement the necessary vertex data for the object (cube). What would be the point of using indices? void CreateCube() { ...
5
votes
2answers
442 views

How to use OpenGL functions from multiples thread?

I'm writing a small game using OpenGL. I'm implementing basic networking in this game and I'm facing a problem. I have a thread in my client socket class that check for available data, when there ...
5
votes
1answer
17k views

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 ...
5
votes
3answers
929 views

How portable are OpenGL versions, really? [closed]

If I write a game engine that uses OpenGL 1.5 (not assuming what else I do), is it portable now and is it still portable five years from now or are/will support for OpenGL by hardware and drivers (be) ...
5
votes
2answers
1k views

Is the “impossible object” possible in computer graphics?

This may be a silly question but I want to know the answer to it. I saw this thing called the "impossible object", while they're many different images of this online, it's suppost to be impossible ...
5
votes
2answers
2k views

Sprite batching in OpenGL

I've got a JAVA based game with an OpenGL rendering front that is drawing a large amount of sprites every frame (during testing it peaked at 700). Now this game is completely unoptimized. There is no ...
5
votes
3answers
1k views

How do I find out which functions are deprecated for specific OpenGL profiles?

I would like to get the list of functions that are part of a certain OpenGL profile and the list of the ones that are deprecated so that I can avoid those.
5
votes
5answers
822 views

What are some low-level performance tweaks for iPhone games written in c?

I'm interested in some performance tweaks for a relatively simple OpenGL ES based 2D iPhone game. What performance tweaks have you found? The performance of the game is pretty good on most devices ...
5
votes
1answer
2k views

Normal transformation and homogeneous coordinates

I'm very confused about the math behind the model/affine transformation expressed in homogeneous coordinates. Reading this article, I understood that a generic vector is transformed by multiplying it ...
5
votes
3answers
6k views

How can I get started programming OpenGL on Mac OS X?

I'm trying to start OpenGL programming on a Mac, which brings me into unknown territory on a lot of things. During the day, I'm a Web Developer, working in C# and before that in PHP and Delphi, all ...
5
votes
2answers
5k views

Constant game speed independent of variable FPS in OpenGL with GLUT?

I've been reading Koen Witters detailed article about different game loop solutions but I'm having some problems implementing the last one with GLUT, which is the recommended one. After reading a ...
5
votes
2answers
1k views

3D models on 2D tilemap perspective when scrolling

I am creating a small top-down game, where the player traverses a 2D tilemap, with an illusion of depth provided by 3D models for things like buildings or trees. Having gotten to the point where I ...
5
votes
3answers
14k views

How to draw 2D images using OpenGL, in SDL?

After everything, I managed to find a simple piece of code that shows how to draw a 2D image with openGL: #include "SDL/SDL.h" #include "SDL/SDL_opengl.h" #include "SDL/SDL_image.h" ...
5
votes
2answers
3k views

Updating texture memory via shader?

What the title says.Is it possible to update a texture via a glsl shader ? Something like : //Read vec4 Pixel = texture2D(TextureID,gl_TexCoord[TextureIndex].st); //Write to texture memory ? vec4 ...
5
votes
3answers
18k views

glTranslate, how exactly does it work?

I have some trouble understanding how does glTranslate work. At first I thought it would just simply add values to axis to do the transformation. However then I have created two objects that would ...
5
votes
2answers
785 views

Atmospheric Scattering

I want to add some nice atmospheric scattering to my 3D game engine but I am very concerned with conserving resources. I am not very familiar with how its done but can someone please give me some ...
5
votes
4answers
380 views

OpenGL lighting appears to be clamping

I'm experiencing an odd problem where everything placed in front of my light appears black in my scene. This happens on multiple axes. I've searched the depths of the internet to find a solution, but ...
5
votes
1answer
529 views

What is the maximum number of shaders I can have in OpenGL 4?

What is the maximum limit of shaders I can have on the GPU? With 1000 different objects, I might have 1000 * 5 shaders (vertex, tcs, tes, geo, frag) on the GPU at a time. Though only one will be ...
5
votes
4answers
742 views

Creating a voxel world with 3D arrays using threads

I am making a voxel game (a bit like Minecraft) in C++(11), and I've come across an issue with creating a world efficiently. In my program, I have a World class, which holds a 3D array of Region ...
5
votes
1answer
1k views

deferred rendering and point light radius

I use a common attenuation equation for point lights: attenuation = 1 / kc + kl * d + kq * d^2. I use deferred rendering so I need to know a light radius. An example light has following intensity: ...
5
votes
3answers
2k views

Can you dynamically set which texture to use in-shader?

I'm working on a user interface system, and I want to be able to mix textured polies with frag-coloured polies. Here's my shader code, that doesn't work: attribute vec2 vertex_coords; attribute float ...
5
votes
2answers
1k views

Disadvantages of using multiple versions of OpenGL in LWJGL?

So, I'm trying to figure out LWJGL, and my goal is to use OpenGL 3.2 (because pretty shaders are pretty). But in every tutorial I can find for LWJGL, they import a bunch of different OpenGL versions ...
5
votes
2answers
2k views

Integrate LibRocket With SDL And OpenGL

I been currently involved in a game project and we reach the point we're want to added the GUI for menus and other stuff but the time that we maybe spent developing our own system could cost us a bit ...
5
votes
2answers
766 views

Which are the most futureproof languages for graphics (shader) programming?

I have written some GLSL and Cg shaders a couple years back. I am starting another graphics engine project and I want to choose my technologies carefully so that my code will be accessible years down ...
5
votes
2answers
1k views

What is causing these texture edge artifacts on some video cards?

I have a 2d heightfield converted into a very simple mesh and textured with tiles from a texture atlas. The tiles texture is drawn with: glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP); ...
5
votes
1answer
801 views

How do particle systems work?

I want to implement a particle system in my game, but I've never programmed a particle system and don't know where to start. I only want to display pixels (GL_POINTs) with different sizes in ...
5
votes
3answers
6k views

Open Source Engine for RTS [closed]

I must write a cross-platform real-time-strategy game within 2-3 months. I want use C++ and OpenGL and am looking for an engine. The engine must be open source and work under both Linux and Windows. ...
5
votes
4answers
4k views

Can't understand these UV texture coordinates (range is NOT 0.0 to 1.0)

I am trying to draw a simple 3D object generated by Google SketchUp 8 Pro onto my WebGL app, the model is a simple cylinder. I opened the exported file and copied the vertices positions, indices, ...
5
votes
1answer
643 views

Is a 10 meg 2048x2048 bitmap too big a size texture to use in an OpenGL game?

This is a speed question, I have a texture, which is 2048 per 2048, the texture is designed to run in big resolutions (1920x1080 for example). The problem is, that the texture have a size of 10MB in ...
5
votes
2answers
222 views

Game has noticeable frame drops but when through a profiler it always runs smooth

I'm trying to optimize my PC game but I can find the bottleneck since every time I run it through a profiler (gDEBugger) it runs smooths. When running outside gDEBugger I get these annoying hiccups. ...
5
votes
2answers
2k views

Should the modelview and projection matrices be calculated in the shader or on the CPU?

At minimum I would have a camera with rotation and world position; projections parameters such as angle of view and perspective vs. orthographic; and meshes with scale, angle, and world position. ...
5
votes
1answer
2k views

Bones Animation - Matrices and calculations

We are 'on final' when it comes to finishing the project, but just before implementing the animation system. Our Client decided to choose "Bones Animation" - which is that I should export each ...
5
votes
3answers
632 views

Should I implement anti-aliasing by rendering large and scaling down?

Having read about anti-aliasing, I came to realise that I could render my scene 8× the original size of the screen, then shrink it to render it on my original screen to improve the effect that I have ...
5
votes
2answers
1k views

Generating geometry when using VBO

Currently I am working on a project in which I generate geometry based on the players movement. A glorified very long trail, composed of quads. I am doing this by storing a STD::Vector, and removing ...
5
votes
2answers
1k views

3D primitive rendering library

I am looking for a library which would easily allow me to render shapes (cubes, spheres, lines, circles, etc.) in 3D3 and OpenGL if possible. I want to be able to rapidly design visual debugging tools ...
5
votes
1answer
221 views

Why bother with a separate normal matrix, if there is never non-uniform scaling on the view matrix?

I am updating one of my shaders to a version of OpenGL/GLSL that doesn't automatically provide gl_NormalMatrix (for educational purposes; I'm not ripping out working code for the sake of it). ...
5
votes
2answers
371 views

Include deprecated OpenGl “immediate mode” context in OpenGl 4?

I'm working on an app that uses immediate mode in all of it's draw routines and I'd like to keep those functions intact when updating our graphics drivers to OpenGl 4. My intention is to get the app ...
5
votes
3answers
9k views

Importing and Displaying .fbx files

I have a little problem with importing/displaying .fbx files. I checked the examples but the ones which I am intrested the most (animation and texture) are badly documented for understanding by ...
5
votes
1answer
868 views

Batching dynamic sprites in OpenGL

I'm trying to wrap my head around how batching is done in a 2D sprite-based game. My understanding is I'd get the vertices that represent each sprite I want to draw and stuff them all into a single ...
5
votes
1answer
646 views

Cheap ways to do scaling ops in shader?

I've got an extensive world terrain that uses vec3 for the vertex position attribute. That's good, because the terrain has endless gradations due to the use of floating point. But I'm thinking about ...
5
votes
1answer
2k views

How do engines like Unreal relate to OpenGL or D3D?

Well I'm completely completely new to computer graphics and even more to game development. I am searching info and all that stuff to have the basics quickly. But there's a big question mark in my ...
5
votes
2answers
1k views

How can I make the switch from immediate mode to VBOs?

I've been using OpenGL for a short time now- and I'd like some clarification on VBOs. As I understand it, a VBO is an object stored on VRAM. In immediate mode, to apply a texture we simply bind it and ...
5
votes
1answer
573 views

How to insert and remove blocks quickly in a Minecraftian world?

I currently have volume data for the world stored as an array of booleans. I then check each empty block and if it has non-empty neighbors the faces get drawn. This prevents me from sending a bunch ...
5
votes
3answers
5k views

how to add water effect to an image

This is what I am trying to achieve: A given image would occupy say 3/4th height of the screen. The remaining 1/4th area would be a reflection of it with some waves (water effect) on it. I'm not sure ...