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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17 views

Need ideas for a space game

I am Tyler and I am 17 years old. I have been learning C++ over the last few months and I am also working on creating a game that i hope will rival already established space MMOs one day such as ...
0
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1answer
68 views

What is the correct approach to implement multiplayer in a game? [duplicate]

I'm developing a game and it is intended to be a multiplayer game. I have experience in writing servers and clients in Java, but the game is written in C++. The server will be written in Java for ...
1
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0answers
15 views

Environment mapping - cube mapping using OpenGL

I'm trying to do cube mapping. Problem is that I'm getting this: This is what I get when I rotate it: But it should look like this Here is code for vertex shader varying vec2 tex_coord; void ...
2
votes
1answer
59 views

GLSL 330 Core Bug? - Uniform variable will not set to value if it is named a certain way

In the code below I have a uniform variable named "vw_matrix" used in the calculation for gl_Position. When I run my program, a rectangle gets printed to the screen. #version 330 core layout ...
0
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0answers
28 views

How to calculate per vertex normals? (OpenGL) [duplicate]

I am really confused and quite much thinking about how to do that? Cross product and then, normalizing is not working for me. Or perhaps, I take them all wrong. Well, please explain me that while ...
1
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1answer
31 views

LWJGL: loading textures of various types

I googled around a bit and nobody seems to have asked this question. I have images in multiple color formats (all of them are PNGs). Most of them are ARGB but my bitmap fonts are gray scale, and I ...
0
votes
0answers
29 views

Differences between OpenGL in OSX and PSX [closed]

Recently, Square Enix launched an OSX client for Final Fantasy Heavenward, and the performance is less than stellar. It was developed by Transgaming, and is essentially the Windows client wrapped in ...
1
vote
0answers
26 views

Certain random content rendering differently

On the main menu of my game there is (obviously) several buttons. 2 of which, in different positions on different screens, render a different colour to the rest. As you can see below, "New game" ...
0
votes
3answers
103 views

Loading models with opengl

I'm developing a video game using OpenGL as graphic API and C++ programming language, and I'm creating all models with blender. One question I have is how you deal with models (vertices), I mean, ...
1
vote
1answer
46 views

How to debug a GLSL shader? [duplicate]

I cannot find any tutorial in Google and Youtube. I have a C++ program that uses OpenGL ES 2.0 API to render something on the screen. How can I debug my shaders? Any step-by-step guide? What is the ...
1
vote
1answer
30 views

3D Studio MAX dxf model to OpenGL and DirectX

Main Question I saw this Loading and Animating MD5 Models with OpenGL an old post explaining .md5mesh .md5anim files. Is there any similar alternate mechanisms? Additional Questions 1.) Is there an ...
0
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1answer
27 views

Performance overhead on Non-POT Texture in POT Atlas

Using atlas, we can reduce memory and draw call. And the atlas is usally POT(Power of Two) Texture. And I know non-POT texture have a lot of GPU and memory performance overhead. (link) I have many ...
0
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0answers
18 views

What is the convention for column-major order matrix transformations?

According to this cheat sheet for CG, if I want to use column-major order for my matrix/vector math I have to multiply from the left applying transformations from right to left, i.e. v' = P * V * v I ...
0
votes
1answer
12 views

Open GL: How to map point inside frustrum to normal device coordinates (NDC)?

I read this article http://www.songho.ca/opengl/gl_projectionmatrix.html. It's explain how calculate projection matrix coefficients. But I completely can't understand how author perform mapping from ...
0
votes
1answer
50 views

How to put the “camera” inside a cube in OpenGL

I'm really new to OpenGL and can't seem to figure out how to put the "camera" inside the cube I've created so that I can move in an FPS-like style. I tried to use gluLookAt and gluPerspective but I'm ...
1
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0answers
9 views

CanDraw in large hierarchical scene with rotation

I've been assigned to write small simulation visualization, that contains thousands of cubes (I know you heard that before). Now I'm working on optimization of stuff that takes place there, but ...
0
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0answers
13 views

glColorPointer not working

I have this problem. The collection of triangle STL is rendered with some default color but the color that is stored in m_pDisplayedColors is not set. I would be thankful if someone points out the ...
2
votes
0answers
143 views

Texturing Objects in OpenGL

Using OpenGL tutorials found here, I constructed an .obj file loader as well as a texture file loader using SOIL. I have an issue with drawing a textured object. (Shown here) Assuming I created the ...
1
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1answer
41 views

How can I rotate a quad around it's center?

My code is: GL11.glPushMatrix(); // rotate around center GL11.glTranslatef(-200/2, -200/2, 0); GL11.glRotatef(30, 0.0f, 0.0f, 1); GL11.glTranslatef(200/2, 200/2, 0); // draw quad ...
0
votes
1answer
66 views

How can I blend up to 3 textures on a polygon without blend maps?

For my voxel game I need to blend up to 3 textures in the same polygon. It would be preferable if I could specify a texture id for each vertex, but other solutions are accepted as well. Here's an ...
0
votes
2answers
92 views

Game engine openGL operations scheduling

I'm making a custom engine and after much research, i realized that the state changes and the vertex or texture data loadings to VRAM are the most slow operations. So I want to optimize it making a ...
0
votes
2answers
40 views

“Render” unsigned integer values to texture without clamping to [0,1]

I am trying to render to an unsigned integer texture, with a blending function enable, so that in the end, the value in each texel will be the number of objects rendered on the texel. So I assume I ...
0
votes
1answer
36 views

Geometry Struct and glDrawElements

currently I re-write my codes and change them to make they are better. I have vertex struct like this: struct SVertex { float X, Y, Z; }; struct STexCoord { float U, V; }; And I re-wrote ...
0
votes
1answer
34 views

How can I render text using the new(ish) JOGL GPU curve rendering classes?

I'm fairly new to OpenGL/JOGL, working through various tutorials and books and making steady progress. Text, however, is an area where I'm stuck. I figured out one way using BufferedImage and ...
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votes
0answers
47 views

.obj file parser : how to render faces? [closed]

Okay so I managed to read a file contents , scan and store it's data into variable then push_back them into vectors for both vertex and faces however, I do not know how to use the faces and or if this ...
2
votes
0answers
38 views

Opengl Skybox Texturing Error

I'm using cubemaps to render a skybox in my game. Thinking this would be a simple task I threw some stuff together using the tutorials I found online, particularly this. Taking all of this together, ...
2
votes
1answer
57 views

Looking for specific “textured quad” openGL tutorial in c++ [on hold]

I'm new to openGL and I've been googling around for the old and simple textured quad tutorial in openGL but I haven't been able to find one that suits my needs. OpenGL3.X compatible OpenGL|ES 2.0 ...
1
vote
2answers
133 views

How to implement Index Buffer Object (IBOs) with texture coordinates in OpenGL?

I was using IBOs to render meshes (for example a cube) from wave-front files (.obj), without texture coordinates or normals, in OpenGL. Following this, I attempted to implemented texturing. The mesh ...
0
votes
0answers
18 views

AttachThreadInput and PeekMessage Threading

I have a problem with AttachThreadInput and PeekMessage from User32.dll while multithreading. PeekMessage is not returning true in any case. I am designing a Windows Form that uses OpenGL rendering ...
3
votes
1answer
73 views

Texturing in OpenGL, Should texture coordinates be assigned to vertices in the shader?

I attempting to texture 3D models (a cube for example) using ibo’s, with OpenGL in Java. Currently, my textures are distorted. I believe this is because only a single texture coordinate is being ...
0
votes
1answer
30 views

Cannot Get The Texture Showed Up Correctly glDrawElements

I still have this problem almost 1 month. Tried to search on Google but did not find any solution to this. I have loaded all the data correctly but don't know why the texture came up like this. Here ...
1
vote
1answer
58 views

Deferred rendering: camera inside point light's sphere of effect

I'm trying out deferred rendering and I'm using the tutorials at http://ogldev.atspace.co.uk. I've got the basics working and I'm currently trying to implement the final step from tutorial 37 ...
0
votes
0answers
30 views

Vertex Skinning OpenGex Incorrect Transformations

I'm following the formula here, I'm using LJWGL, OpenGl, OpenGex, and Blender: I implemented the code and it works but there is a few things. First, there is a gap between the two bones, or on each ...
1
vote
0answers
74 views

Implementing a Render queue [closed]

I am currently in the process of re-writing my 3d engine, and I am looking at improving the renderer. I have read that organizing objects into a "render queue" and sorting is the best method. The ...
0
votes
1answer
58 views

Error drawing two VAO, each one using different shader programs (vertex + fragment shader) in OpenGL Core 4.3 / GLSL 430 (SOLVED)

I am trying to draw over a GL_TRIANGLE_FAN one texture to render video frames, using shaderProgram1, and render above it some points (GL_POINTS) using shaderProgram2. By this way: (OpenGL Core 4.3) ...
5
votes
2answers
148 views

Low quality bilinear sampling in WebGL/OpenGL/DirectX

I'm seeing low quality bilinear texture sampling in WebGL, OpenGL and Directx, and was wondering if anyone knew how to make it higher quality? The picture below should help show what I mean. The ...
1
vote
0answers
48 views

Taking a 2D slice of a 3D volume

I have a regular 3D polygon and I'd like to display 2D slices of it. What is the best way to achieve this? (Preferrably in OpenGL, but a general algorithm/tecnique would be good as well). I've ...
0
votes
0answers
30 views

LWJGL OpenGL Spotlight half-showing

Problem: Only half of the light is showing. Lighting Inilization code: glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glEnable(GL_DEPTH_TEST); glEnable(GL_NORMALIZE); ...
36
votes
1answer
6k views

Why are all OpenGL function calls prefixed with “q” in the Doom 3 source code?

Why is every OpenGL call prefixed with a "q" in the Doom 3 source code? Are they custom functions or a different library, and if so, why use that over OpenGL? Any Google search comes up with the Qt ...
0
votes
0answers
26 views

How can I render several rectangles efficiently? (LWJGL)

I'm working with OpenGL3+ rendering and I am coming from OpenGL1.5. In GL1.5 I had rendered things like this: public class GraphicsDead { int vboVertexHandle; int vboColorHandle; public ...
1
vote
1answer
53 views

How can I manipulate a single pixel with LWJGL?

This is a very simple question. Is there a way to manipulate a single pixel? Here's an example of what I want in pseudo-code: while(gameIsOn) { renderAllObjects(); setPixel(x,y,r,g,b); } ...
0
votes
1answer
41 views

Using of opengl buffers

Newbie question, and sorry for my English. Suppose that we create a lot of GL_ARRAY_BUFFER buffers, fill them with some data. But only few of them we link with shader variables. During glDraw..., what ...
0
votes
1answer
32 views

LWJGL Lighting advice / fix

Problem: The spotlight I've set up with OpenGL won't light up anything behind it, no matter what values I set for GL_SPOT_DIRECTION float[] LightDir = new float[]{0,0,-1,0}; float[] ...
2
votes
1answer
311 views

Do I need to install any libraries or SDKs to use OpenGL?

I am wondering if I have to install libraries for openGL programming or if I can already use header files from the core library. I am asking this because I went to the SDK and there is no Core library ...
0
votes
2answers
61 views

Move towards view direction opengl?

I'm trying to get the basics of 3d with opengl 2.0(I know, I know, it's deprecated etc, etc. It's just for the sake of prototyping). I'm trying to get a cube on the screen which you can move around. I ...
0
votes
2answers
64 views

Is Global location using OpenGL bound by the shader?

I have recently started writing a game engine in C++ with OpenGL and using some tutorials online. So far from what I have seen, shaders are the way to manipulate an object's position in worldspace. Is ...
0
votes
1answer
62 views

glDrawElements and Texture Coordinate

I just move on from Immediate Mode and try Vertex Array method using glDrawElements and I got the texture is mess. How to draw the texture correctly? This is a piece of my render code ...
1
vote
0answers
60 views

Normal Mapping a Cubemap

I posted a question on Stackoverflow and it was suggested that it would be better asked here. I have a sphere. It was created via the icosphere method outlined here: ...
3
votes
2answers
504 views

How do I use graphics APIs to select the proper display device among multiple attached to a PC?

I have an LCD monitor display and Oculus Rift attached to my PC. I have an Nvidia 820M dedicated GPU. How does the GPU know to which display device it has to render (or to send rendered information)? ...
0
votes
1answer
74 views

Deferred Rendering with SFML

I've been looking to implement a deferred rendering system in SFML. I've read the tutorials on OGLdev for it, and I was wondering how to draw a scene built in SFML (sprites, text, etc) to the ...