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
2answers
130 views

In OpenGL, how to confirm a primitive is rendered properly

I have to confirm that a primitive (say triangle) is rendered properly in opengl. I can use the glGetError() after a opengl draw calls(glDrawElement/glDrawArrays) Is it enough to confirm ? Is there ...
9
votes
2answers
1k 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 ...
1
vote
3answers
2k views

Replace glTranslatef and glRotatef with matrixes

I'm not an opengl expert, and, as a novice, I prefer to practice a little bit with the old opengl just to be sure to understand correctly the basic concept of computer graphics before deal with ...
2
votes
1answer
591 views

OpenGL and constant buffers

I'm doing a small direct3d11 project for "fun". I know d3d11 quite well but not really any opengl. My program is designed for d3d11 but I would like it to be easy to port to opengl at some point so ...
0
votes
1answer
569 views

How do I orbit one object around another?

I am trying to do animation using glut. I have 2 squares overlapping to each other and i want other square to rotate around this central object without rotating themselves. I want to rotate in orbit ...
3
votes
1answer
666 views

Alpha Blending performance on IOS

I've got few questions without responses about my game development, can you help me? Here is the questions: In my game when a large object appear on the screen, the GPU go to his limits, my ...
1
vote
1answer
407 views

Unable to Render to multiple rendertargets

I am trying to implement a simple deferred rendering engine in openGL and i have a little problem with the GBuffer. I cant get it to render to more than one texture at a single time, which is the one ...
2
votes
0answers
250 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" ...
1
vote
0answers
505 views

How do I mix 3D skeletal animations?

I'm trying to create a 3D-model skeletal animation system for C++/Open GL. I would like to be able to mix animations by allowing animations to only affect specific bones. My game has ride-able ...
4
votes
1answer
478 views

OpenGL FBO not being drawn to

In my project I'm trying to implement a deferred rendering system, problem is, I can't seem to get a second FBO to work. UPDATE 1 Here is the FBO initialization code: /// G-Buffer FBO GLuint ...
3
votes
1answer
2k views

Combining rotation,scaling around a pivot with translation into a matrix

In short: I need to combine rotation (in the form of a quaternion), scaling around a pivot point along with translation into a transformation matrix. The long: I am trying to implement a proprietary ...
1
vote
0answers
113 views

Slick2d font rendering makes all other drawings vanish

I'm converting a java game to lwjgl and slick-utils. I've followed the slick2d examples for font loading/rendering but I found that the font shows as a solid box of color unless I add the following ...
2
votes
1answer
97 views

Expandable player boundaries

I'm trying to plan how to implement non-fixed boundaries so the player can expand their controlled territory without using a tiled based system. Each pixel can be fought over for who controls it. I ...
1
vote
1answer
177 views

Android Object get Jagged at the border

I am new to OpenGL ES 1 in android. My 3D Model border getting Jagged. Please help me to look like a smooth border instead of jagged. Screenshot : http://i.stack.imgur.com/1Gq83.png private class ...
3
votes
1answer
330 views

what's the best way of panning in a 2D scene

Up to know I have used this functions to create a 2D scene (for showing images) and to pan on it ( in fact it's a customization of the class COpenGLControl here in codeguru) : void ...
0
votes
1answer
169 views

Is there a need to set the parameters again when updating a texture?

Suppose that I'm developing the class COpenGLControl here in code guru to use it for showing a 2D texture in an MFC CPictureControl. and after applying some filters on the image, I will update the ...
4
votes
1answer
152 views

Can you help me solve the paradox that has confused me about the glViewport and glOrtho functions?

suppose that I have an image that I want to apply as a texture on a geometry (at time we don't consider texture mapping but this image has a certain width and height here it is a 512x512 image) I want ...
1
vote
1answer
108 views

How to render models using a personalized projection matrix?

I'm creating a game with a great sprite demand. Out team is considering automatizing the sprite generation using 3D models. The problem is we have a very particular ortographic projection: We have ...
8
votes
3answers
563 views

Why is it possible to encounter a texture coordinate greater than 1 or less than 0

I'm studying a text about texture mapping and in the preparing to draw session, I read: Define the texture wrapping parameters. This will control what happens when a texture coordinate greater than ...
2
votes
2answers
367 views

Split up a screen into regions

My task: I want to split up a screen into 3 regions for buffs-bar (with picked items), score-info and a game-map. It doesn't matter are regions intersect with each other or not. For example: I have ...
4
votes
1answer
2k views

How do I draw a full resolution texture to a window of the same resolution?

My image is 1280x800, and my screen size is 1280x800. It should draw perfectly. I'm creating a quad the size of the screen, and setting the texture to fit the quad. But right now it draws a square ...
2
votes
1answer
427 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 ...
1
vote
1answer
154 views

Using an FBO texture and write to it

I wanted to know if it's possible to use a texture of an FBO for post-processing and using that texture again for writing or do I need at least two textures? I hope you understand what I mean.
1
vote
1answer
282 views

Drawing a textured 3D object breaks SFML text render

I writing a OpenGL game using SFML. I'm using the push/pop function to combine OpenGL with SFML like the tutorial SFML+OpenGL but, when I added textures to my model, the SFML text rendering appears ...
0
votes
1answer
84 views

How to rotate the camera to point to a specified location?

I have a quaternion based camera class (which controls a view matrix) and would like a function to rotate the camera to face a specified point. The best approach I can come up with is that I rotate ...
1
vote
1answer
912 views

Marching Cubes Terrain [closed]

For the past week I've been researching the Marching Cubes algorithm. I hope to use this for Terrain as it would allow the creation of destruction of terrain. After looking at source code and reading ...
6
votes
1answer
841 views

How would one draw many objects using the same VBO

I'm kind of stuck with this question for some time now, maybe because I don't know exactly what to search for, it might be a term I have not heard of yet as most tutorials ends after drawing one ...
0
votes
1answer
211 views

An API independent way of managing video memory?

I'm developing a game. The game architecture is very modular. I have a "Graphics Engine", which uses either a Direct3D or OpenGL renderer. However the user does not have access to the renderers ...
4
votes
3answers
647 views

How to achieve rendering at huge distances?

These days I was reading some information about the upcoming GTA V technology, in particular, how it is able to truly render all buildings you can see without a draw distance cap or any faking. Since ...
0
votes
2answers
1k views

Draw wireframe overlay of model in GLSL

I have a 3D model that has a GLSL script, and I want to draw a line on each border of its polygons in the fragment shader. What should I do? Note: I am using Ogre3D, so I can't use OpenGL's ...
1
vote
1answer
113 views

Pyglet: How to use second screen's vsync

does anybody know if it's possible to use the vsync of the second monitor instead of the first one with pyglet? I have 2 monitors, one running at 60Hz and the other at 120Hz. I want to be able to ...
3
votes
0answers
481 views

Jet engine exhaust shader [closed]

How would I create a jet engine exhaust effect, as shown in the image from Fzero GX below. GLSL and OpenGL examples/solutions are prefered, though other resources are also welcome. Requirements ...
1
vote
2answers
695 views

OpenGL draws draw buffers in wrong order

I'm trying to implement deferred rendering and for now I only have diffuse, normal (in world space) and position (in world space) as textures inside the GBuffer. I create the GBuffer like this: void ...
3
votes
2answers
2k views

OpenGL GL_LINE_STRIP produces arcs with visible line edges

Another member mentioned an issue while drawing arcs with GL_LINE_STRIP. He has GL_LINE_SMOOTH enabled. The question is, how could he avoid the tiny gaps between vertices without increasing their ...
3
votes
1answer
299 views

GPGPU physics & game logic

I'm wondering about gpu accelarated physics after reading about Erwin Coumans presentation on GPU accelerated physics: http://www.gdcvault.com/play/1018185/GPU-Rigid-Body-Rigid-Body (demo video here: ...
6
votes
1answer
524 views

Sprite with alpha Blending in 3D world

I'm working on a game in a 3D world with elements 2D only (Like Don't starve game) for Android and IOS. Currently, I've managed "Sprite" without alpha blending, I've just put a condition in the pixel ...
3
votes
2answers
82 views

Local shape color blending

I am trying to implement this in Unity 4 Pro. But I am stuck in the blending part. I don't understand how you could blend multiples textures/colors using multiples volumes on an object. How could you ...
0
votes
1answer
233 views

Creating a fragment shader to darken a white texture over time - OpenGL GLSL

So as a part of learning OpenGL, I've now decided to try and be a bit more creative with shaders, as part of a practice game I'm making using C/OpenGL. I'm completely new when it comes to working ...
0
votes
0answers
170 views

Shadow-casting through time acting in “reverse” before next notciable shadowmap update

question was re-written to better explain the problem I have a scene of big thin parallelepiped, small cube, and a light source, all aligned on Y axis, like so: _ | | | |----[ ]----Light |_| Both ...
-1
votes
1answer
261 views

OpenGL: How to map textures to geometry without using filter parameters

following my another question I have studied in the documentations that I should use this procedure : Define the texture filter parameters. This will control what happens when a texture is scaled ...
4
votes
1answer
75 views

OpenGL Maximal amount of debug string reached

I was trying to check my current openGL code in gDEBugger, everything works fine. But, I get these messages Debug String: >>>>>>>>> 1 Debug String: ...
2
votes
1answer
422 views

What happens when a texture is too large for a device

The question is two fold: What happens on a device when a texture is too large for it to handle? Will it crash or simply downsize it? In Unity if I use texture atlases of size 4k and then set ...
4
votes
1answer
404 views

How do I draw a zoomable image in OpenGL?

Up to now I have used glDrawPixels but since my image is a large geotiff one, I'm getting some horrible results for example: this is the code used for zoom extent: void ...
2
votes
2answers
2k views

How to check for cube collisions?

I want a method, which takes two "ObjectBox" objects (A "ObjectBox" has .getX() .getY() .getZ() .getSizeX() .getSizeY() .getSizeZ() methods) as a parameter and return true if the two Boxes are ...
14
votes
2answers
1k views

What advantages does bare OpenGL provide over frameworks/engines to small developers? [closed]

I've noticed a trend of indie developers steering away from frameworks and engines, and moving towards using bare OpenGL, or using it combined with SDL/SFML2. As an indie developer, I can't see what ...
1
vote
0answers
207 views

Rotate a point in 3D space with sine and cosine

I got my camera controlled by the mouse. Now I want a sphere to be always in the center of my view(just for testing). I tried that by assigning the sine of the Y rotation of the camera times 10 as the ...
0
votes
1answer
151 views

Camera coordinate system flipped?

I'm looking do make an FPS-like camera, but I'm encountering some problems. If I'm first rotating and then translating the camera, everything works fine, but the coordinate system. For example, if I ...
5
votes
1answer
3k views

Implementing a skybox with GLSL version 330

I am trying to get a skybox working with OpenGL 3.3 and GLSL version 330. I could not find a completely modern OGL skybox tutorial anywhere on the web, so I modernised an older one (using ...
1
vote
1answer
849 views

Create a fly camera with lookAt

I want to create a free cam with the lookAt matrix in OpenGL. I just made the control with W, A, S and D so you can move around. But now I nee to look around. I thought doing that with sine and cosine ...
0
votes
1answer
1k views

How to find monitor resolution with glfw3?

For a while now, I have been playing around with making a game using OpenGL, and glfw3. I have been perfectly happy to create windows at my native resolution of 1920x1080. I'm getting to the point ...