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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2
votes
1answer
122 views

Drawing fonts with LWJGL3 with OpenGL

I'm very sorry if this question has already been answered, but since I've been struggling with this for many days I thought I'd give it a shot here. My goal is to somehow render some text on the ...
2
votes
1answer
96 views

Proper normal vector transformations in normal mapping

Hello! This question is about transforming normal vectors from normal maps properly. I have tried methods from over five sources, still can't get it to work, and I'm really desperate. Included are ...
2
votes
1answer
106 views

How to handle the birth and death of particle without reading from the buffer

I've implemented a simple particle system where each particle has a position, velocity, age and lifespan stored in different SSBOs. Most of the data including all the position, velocity and age is ...
2
votes
0answers
51 views

OpenGL enabled Java game not detected by Fraps

Recently I found out that I could enable OpenGL hardware acceleration in my java game with the line System.setProperty("sun.java2d.opengl", "True"); Initial tests showed a big boost in performance. ...
2
votes
0answers
84 views

OpenGL Planet Generation - Simple Matrix Issue (Planet “Spins” With Mouse)

I originally asked this question on StackOverflow & was directed here by a commenter. Im currently working on a OpenGL planet rendering. I'm using the Tessellation pipeline. So far things are ...
2
votes
0answers
113 views

How much is atomicAdd slower than an atomic counter?

I am considering replacing an atomic counter in my shader code with a SSBO an atomicAdd operation. What I need to know is the difference in performance of these two. I know the atomic counter executes ...
2
votes
2answers
55 views

How do find the right GLxx object for a given function in LWJGL?

I'm just starting to learn the fundamentals of OpenGL via LWJGL. Every OpenGL function is implemented as a method on a GLxx class. The xx corresponds to the version of the spec when that function was ...
2
votes
0answers
59 views

Tangents face the same direction on opposite sides of mesh

I have noticed that the tangent vectors that I am calculating are not always facing the correct direction. The tangents on the left and right of the mesh both face the same direction. Here is a ...
2
votes
1answer
270 views

What is the correct multiplication order for a 2D matrix?

I'm currently trying to create a camera and entity/model matrix for my 2D game similar to that of Unity3D. I've already tried to find answers to this question on stackoverflow/gamedev but i couldn't ...
2
votes
1answer
180 views

Selection with region (when rendering with shaders and VAO)

I am currently render my geometry using "Modern OpenGL" approach (with shaders and buffers). I have already implemented picking of single primitives using glReadPixels. Now I am faced with problem how ...
2
votes
1answer
75 views

Render on texture with alpha 0 for the background colour

Sorry if the question is stupid but I am very new to opengl. I render on a target a scene with a couple of object on a background that is nothing more than the clear colour (which is ...
2
votes
0answers
77 views

SDL_AddTimer + SDL_GL_MakeCurrent not working on Windows [closed]

I'm messing around with C++, OpenGL and SDL doing a game that should be able to run in Windows and Mac OS X. I have a problem that only happens on Windows. Let me describe the scenario. First I ...
2
votes
1answer
294 views

How I reuse the same vertex data, but have different colors, for my sphere objects?

I'm using OpenGL to display a 3D network, with nodes represented as spheres (I haven't gotten to edges yet). I'm a total novice, and having a bit of trouble wrapping my head around OpenGL. These ...
2
votes
1answer
133 views

OpenGL: missing GL_SPECULAR light on the texture

I'am missing specular lighting on the texture. I have #include <GL/glext.h> in the project, so basically I used glLightModeli(GL_LIGHT_MODEL_COLOR_CONTROL_EXT, GL_SEPARATE_SPECULAR_COLOR_EXT); ...
2
votes
0answers
461 views

C++ FPS game collision detection with partitioning system or physics engine? [closed]

I'm working on a small FPS game (as a hobby and for learning purposes, nothing else) built with C++ in OpenGL (from scratch). Documenting online on the kind of strategy someone would approach with ...
2
votes
0answers
414 views

OpenGL drawing 500k triangles [closed]

I want to render big, izometric 2d map (using ortho projection). I am using OpenTK and aiming for OpenGL 3.3. Perfect option would be to draw 512x512 map of tiles, which is 262144 blocks -> 524288 ...
2
votes
0answers
1k views

Normal mapping does not work correctly using GLSL and OpenGL [closed]

Hello I wrote a simple OpenGl program using GLSL to render a simple uv mapped plane using the normal mapping technics. Here's the display with a simple phong shading (without normal mapping) : Now ...
2
votes
1answer
267 views

How to work with smaller intermediate textures in OpenGL and GLSL?

I'm working on a project rendering water simulated through smoothed-particle hydrodynamics (SPH) with a non-photorealistic look to use in games. In the actual stage of the project everything about ...
2
votes
2answers
286 views

What is the correct way to draw layered Sprites in modern OpenGL?

So what do I mean by layered sprites? Layered Sprites are Sprites that consist of multiple layers, e.g. you have sprite sheets for the basic Body, the Head, Clothes, Weapons, etc. Well now I wanted ...
2
votes
0answers
478 views

Help with 2D sprite instancing [closed]

Alright, so I'm pretty new to OpenGL programming. I've been writing my own engine, initially using the fixed function pipeline. I then did a 1:1 replacement of the fixed-function methods with shaders ...
2
votes
1answer
671 views

glDrawArrays (layered rendering using geometry shader) only draws one point

I have been debugging this for a while but I can't seem to find the issue. I created a framebuffer for layered rendering like this GLuint buffer; glGenFramebuffers(1,&buffer); ...
2
votes
0answers
1k views

Arcball 3D camera

I have checked multiple threads before posting, but i havent been able to figure this one out. Ok so i have been following this tutorial, but im not using glm, ive been implementing everything up ...
2
votes
0answers
278 views

VBO = glGenBuffers() IllegalStateException [closed]

i'm kinda noob in OpenGL but I have this problem: I get an IllegalStateException at this code: int vboVertex = glGenBuffers(); In-detail exception: Exception in thread "main" ...
2
votes
0answers
113 views

How do I calculate the points of a brush from a Source engine VMF? [closed]

I'm trying to render the brushes from a Source engine .vmf file in C++, using OpenGL. The .vmf stores solid brushes as a series of planes which I would like to use to calculate the points for each ...
2
votes
1answer
1k views

Problem using glm::lookat

I am trying to rotate a sprite so it is always facing a 3D camera. Object GLfloat vertexData[] = { // X Y Z U V 0.0f, 0.8f, 0.0f, 0.5f, 1.0f, -0.8f,-0.8f, 0.0f, ...
2
votes
0answers
374 views

OpenGL: Attempt to allocate a texture too big for the current hardware [closed]

I'm getting the following error: java.io.IOException: Attempt to allocate a texture to big for the current hardware at ...
2
votes
1answer
196 views

OpenGL Calculate Matrices

Im trying to switch from the glTranslate etc to my own Matrices, but for some reason it does not work. Here are my 2 functions to create the view- and projection matrix: public Matrix4f ...
2
votes
0answers
78 views

uniform z slices in clip-space [closed]

1) Context I'm using a regular OpenGL perspective projection matrix created with GLM (glm::perspective) and taking the inverse (glm::inverse) to transform clip-space back into view space (and world ...
2
votes
0answers
860 views

Converting Mouse Coords to 3d coords with Camera position [closed]

So I've looked at all the answers I can possibly find, and nothing seems to fit what I need exactly (because im bad at math). I'll explain what I have thus far: A camera with x,y,z, Pitch and Yaw ...
2
votes
0answers
336 views

Displacement Mapping opengl-es [closed]

I need to do an application similar to this Morfo. And I posted a question here where the answer states the solution is "Displacement Mapping" . And I googled this to do it in opengles. I couldnt get ...
2
votes
0answers
407 views

glFramebufferTexture2D gives corruption with cube map textures

I am using glFramebufferTexture2D with cube map textures but it gives corruption in texture. draw_cube() function works perfectly when i draw that on default framebuffer. GLenum ...
2
votes
0answers
78 views

Everything turning black when pitching down [closed]

Just a quick questions about something that's occurring in my world. Every time I pitch my camera downward, everything starts turning black, and if I pitch upward, everything sort of intensifies. ...
2
votes
0answers
453 views

Per fragment lighting with OpenGL 4.x tessellated model

I'm experienced with OpenGL 3+. I'm dabbling with tessellation shaders and have now got to a point where I have a nicely tessellated teapot/plane demo (quick look here) As can be seen from the ...
2
votes
2answers
726 views

Is this a reliable method of parsing glGetShaderInfoLog()?

I want to get a list of errors and their line numbers so I can display the error information differently from how it's formatted in the error string and also to show the line in the output. It looks ...
2
votes
0answers
513 views

GLSL Bokeh using Quads and Textures [closed]

I'm trying to create a depth of field effect with bokeh sprites in GLSL. Specifically, what i would like to do is, for each pixel: See if the pixel is out of the focal range If it is, draw a quad ...
2
votes
2answers
575 views

3D Translation using only distance and angles

So I'm starting to foray into 3D game programming, but I've hit something of a snag. I have an object I want to move around. It should always move either forward or backward relative to its local Z ...
2
votes
0answers
1k views

Can one use OpenGL ES from Google Go? [closed]

I've recently used Google's Go language and was impressed by its great support for parallelism. I'd like to try Go for a simple game -- just a test-case -- and I'm wondering if I can use OpenGL ES ...
2
votes
1answer
235 views

How to debug pyglet/opengl bus errors

I'm using pyglet for game development, and sometimes encounter "bus errors". They are not consistently repeatable, and whenever I try to do simple debugging (eg move/remove variables, etc), the errors ...
2
votes
1answer
860 views

Need some help implementing VBO's with Frustum Culling

i'm currently developing my first 3D game for a school project, the game world is completely inspired by minecraft (world completely made out of cubes). I'm currently seeking to improve the ...
2
votes
2answers
7k views

Getting error GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT

I am getting error code GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT when creating framebuffer on Mac (using glCheckFramebufferStatus). I am using same code for rendering on Mac and iOS both. Maybe problem ...
2
votes
1answer
534 views

Problem with arcball

I making graphics viewer, and I want to use "arcball" to manipulate object. I using OpenGL + CML ( for math ). My arcball don't want work, it is skewing not rotating :/ And I don't know why, I use ...
2
votes
1answer
561 views

Xbox Controller Not Connecting in Monogame Project

I have recently been playing around with the support of the wired XBox 360 controller in Windows development. I am developing in C# in Visual Studio 2012. I have created 2 projects. The first ...
2
votes
1answer
786 views

Problem with gluOrtho2D()

I was trying to understand the gluOrtho2D function. I have drawn 4 lines originating from the center reaching up to 4 corners of the screen. You can follow the below code. osize is a variable which ...
2
votes
1answer
452 views

Fog shader camera problem

I have some difficulties with my vertex-fragment fog shader in Unity. I have a good visual result but the problem is that the gradient is based on the camera's position, it moves as the camera moves. ...
2
votes
1answer
346 views

OpenGL Fast-Object Instancing Error

I have some code that loops through a set of objects and renders instances of those objects. The list of objects that needs to be rendered is stored as a std::map>, where an object of class ...
2
votes
1answer
2k views

Opengl-es picking object

I saw a lot of picking code opengl-es, but nothing worked. Can someone give me what am I missing? My code is (from tutorials/forums) Vec3 far = Camera.getPosition(); Vec3 near = ...
1
vote
5answers
1k views

OpenGL Performance Questions

This subject, as with any optimisation problem, gets hit on a lot, but I just couldn't find what I (think) I want. A lot of tutorials, and even SO questions have similar tips; generally covering: ...
1
vote
4answers
2k views

searching for “university kind” free online course about OPENGL [closed]

I know there are a lot of free university courses, but I'm trying to find one about OpenGL. Do you know where can I find one, online?
1
vote
3answers
3k views

Will I have an easier time learning OpenGL in Pygame or Pyglet? (NeHe tutorials downloaded) [closed]

I'm looking between PyGame and Pyglet, Pyglet seems to be somewhat newer and more Pythony, but it's last release according to Wikipedia is January '10. PyGame seems to have more documentation, more ...
1
vote
4answers
440 views

Are VBOs only for OpenGL 3.x?

Are VBOs only for OpenGL 3.x? I'm using immediate mode and I know it's bad, slow, and deprecated. But then I looked at display lists but they are deprecated too. I guess the VBO is the only one left ...