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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82 views

Encoding Float to RG/RGBA and Blending

Encoding a float value inside a RG or RGBA texture is very interesting and useful but it is also become quite useless when you use blending as the result and the values might be altered because of ...
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14 views

How to calculate spherical harmonic coefficients for indirect diffuse?

After reading the article "An Efficient Representation for Irradiance Environment Maps", I'm a bit confused as how to calculate the spherical harmonic coefficients. I'd like to generate these ...
2
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0answers
49 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. ...
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27 views

LWJGL - First time trying to implement shadow mapping

It's my first time when I implementing shadow mapping. My problem is shadows don't work in any way. First I just render all of the object to a FBO with simple shader. shadowMapGenerator.vs: #version ...
3
votes
1answer
187 views

Pyglet: text.Label().draw to FBO?

I just started OpenGL (PyopenGl) & Pyglet 3 weeks ago, and decided to read the Red Book. So sorry if my question shows my lack of comprehension... My question is: Is it possible to display/write ...
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1answer
72 views

How to make TMXTiledMap responsive?

I've been struggling with Cocos2d-x (C++) and finally I got to the point I feel more or less comfortable with that. My game is a 2D car-based one, with a straight infinite map where I've finally been ...
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2answers
104 views

Z-Value of clip-space position is always 1.0

I render a lot of quads on the screen into z direction (20 x 2000). I want to get the depth value in a final render target. But it looks like z is always 1.0f. I checked the result with the OpenGL ...
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1answer
27 views

GL_INVALID_OPERATION on glBindVertexArray Despite glGenVertexArrays()

so I've been trying to create a simpler way to draw polygons and and have come across the following issue: When I call glBindVertexArray(m_VAO); it throws a GL_INVALID_OPERATION even though I have ...
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1answer
36 views

How can I set up a pixel-perfect camera using OpenGL and orthographic projection?

I am creating a 2D game using OpenGL and orthographic projection. For sprites, I use textured quads (actually two triangles). I want the pixel art textures for the sprites to be displayed in a ...
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1answer
44 views

How to display three dimensional Objects in a 2D Game using OpenGL and orthographic Projection?

I am creating a 2D (2.5D) game using OpenGL and orthographic projection. It is simple to have relatively flat objects, e.g. characters. I simply use a quad with a texture of the character and move ...
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3answers
176 views

Passing array to uniform in glsl error

Here is my attemps to pass array to uniform array: struct Vector{ float x,y,z; } float threshold[2] = { 0.5, 0.25 }; Vector *kernel = new Vector[_kernel_size]; // _kernel_size==16 // fill kernel ...
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0answers
53 views

How do I check for collision between transparent textures?

I am creating a 2D game using OpenGL. For sprites, I use textured quads (actually two triangles). The texures contain transparent pixels, since objects are not always perfectly rectangular. How do I ...
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0answers
32 views

Is it recommended to use GLFW for long term projects? [on hold]

The thing is I'm wondering if it is viable to use GLFW in a long project. Since it's a long term project, I don't want to run into a wall when it's already to late to redo important code.
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0answers
35 views

Picking isometric map with slopes

I'm looking for a way to convert mouse/screen coordinates to isometric map coordinates, with the addition that the world has slopes and cliffs, and I have to be able to tell which quadrant of the tile ...
1
vote
1answer
44 views

OpenGL poor performace with instanced drawing

I'm just started learning OpenGL and this is my first project besides tutorials. I'm trying to load a huge enginering model: The data is structured in a way that I thought I could use instancing ...
1
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2answers
302 views

How can I use OpenGL and D3D to render to the same window at the same time?

I have main render loop in which initial drawing is done via OpenGL to an SDL window, and after that the same window handle is passed to a Direct3D device, which does subsequent rendering. Once I ...
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1answer
27 views

OpenGL Shaders Ignored

I have been following this tutorial to try and start learning OpenGL. However, upon compiling my code, my triangle turns out to be black. At first I thought that there was something wrong with the ...
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1answer
117 views

Invalid coordinates returned by glutMouseFunc()

I am using GLUT's glutMouseFunc() function to retrieve the coordinates of mouse clicks. I want to move the object on that coordinate to another coordinate. But when I click on the object the ...
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0answers
39 views

What to choose Game Engine or Make my own? [on hold]

I want to go into game programing, I know basic stuffs in Unity, C++ / OpenGL, and I don't know what is better to make a Game Engine (I'm don't gone write a programing language for it, I will make ...
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vote
1answer
36 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" ...
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0answers
34 views

OpenGL - Make two images blend together

I have 2 images that are .png and they mix together, The problem is that one overwrite the other. I know that the draw order matters, but In that case I should redraw the icons 2 times ( there is a ...
1
vote
1answer
32 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 ...
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1answer
584 views

Geometry shader and triangle adjacency

I'm currently trying to change my project to use GL_TRIANGLE_ADJACENCY instead of GL_TRIANGLES. Following this question, I have managed to construct my index buffer fine, but when it comes to the ...
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0answers
43 views

Blinn-Phong lighting on Voxel models

I'm creating a game that is going to use voxel models. However I got stuck when I coded my shader using Blinn-Phong algoritm. Here is how it look (Only care about the red model): As you can see ...
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0answers
16 views

Nvidia Nsight 4.6 VS Edition. The Graphics debugger can't find glew32.dll

I'm trying to debug some textures and FBO's with Nvidia Nsight 4.6 VS Edition. But when I select either "Start CUDA debugging" or "Start graphics debugging" I get an error. "The program can't start ...
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0answers
34 views

Need ideas for a space game [on hold]

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 ...
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1answer
567 views

How do I build Assimp with MinGW?

How can I build Assimp with cMake and MinGW? I tried, but I don't get a functioning library... Details of my attempt: I am trying to build the Open Asset Import Library (Assimp) but I have been ...
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1answer
273 views

How to compute matrix transform local/world on OpenGL

I'm developing an OpenGL program where each object / entity contains m_WorldPosition, m_WorldOrientation, m_WorldScale and m_WorldTransform (Vector3, Quaternion, Vector3 and Matrix4f). The problem is ...
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2answers
234 views

Tiled Rendering - Projection matrix

I'm trying to figure out how to perform tiled rendering of my 3d scene (OpenGL). The motivation is to cut the scene up into several textures, combining them into a single image for saving at a very ...
0
votes
1answer
88 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 ...
2
votes
1answer
64 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
votes
3answers
107 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, ...
0
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1answer
75 views

Collision between a sphere and a mesh(height-map)

I am trying to implement a method that detects the collision between a sphere and a mesh and reflects the vector of speed. I have a method, that detects a collision between a sphere and a triangle and ...
3
votes
1answer
143 views

FBX Importer - Vertex Color

I imported vertex positions, indices and normals successfully in OpenGL using fbx sdk, but I just can't figure out how to import vertex colors. I tried to fetch the pointer to array of colors trough ...
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1answer
171 views

Trying to implement Camera

I'm trying to implement a Camera class in order to walk and look on the world as follow: #ifndef _CAMERA_H_ #define _CAMERA_H_ #include <glm\glm.hpp> class Camera { public: Camera(); ...
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1answer
70 views

Small text is very light / faint with FreeType and OpenGL

I'm able to render large text with FreeType just fine: But when I want to render small text (and the only parameter that changes is the font size), the quality is much poorer: As you can see, ...
0
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1answer
66 views

Java OpenGL Perspective matrix not working

I'm trying to render a simple triangle with OpenGL in Java using LWJGL3. Everything is working great, but the projection matrix (perspective) is not working. In C++ I just used to apply the ...
0
votes
1answer
67 views

How to clip or mask entity in adnroid/andengine?

I want to implement masking with sprite in Andengine. I want same functionality as in ios class called SKCropNode which works like an masking node! Is there any workaround like this in ...
0
votes
1answer
89 views

How to Load a Level for use with the Bullet Physics Library

I am trying to use a level in .obj format loaded with Assimp to generate a btBvhTriangleMeshShape to use with the Bullet physics library. I can successfully load btConvexHullShapes as well ...
2
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0answers
144 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 ...
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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
vote
1answer
33 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 ...
1
vote
1answer
161 views

SDL & OpenGL - Artifacts when multisampling

Im trying to render a model with anialiasing using OpenGL and SDL, but when I do I get strange artifacts. When I render with antialiasing disabled everything looks fine. When antialiasing is ...
3
votes
2answers
370 views

Is there a way to use scala with html5?

I want to create a very simple 2d multiplayer browsergame in html5. Something like Scalatron I mainly want to do this to improve my scala skills, the problem is I would have to code the clientside ...
0
votes
1answer
61 views

Fragment shader compiling in webGL but not in OpenGL

I am programming in Haxe (language compiling to multiple platforms) and I have written some shaders. My fragment shader runs fine in html5, but when I try to compile for native (OS X and/or Neko, a ...
3
votes
1answer
317 views

Using textureGrad for anisotropic integration approximation

I'm trying to develop a real time rendering method using real time acquired envmap (cubemap) for lightning. This implies that my envmap can change as often as every frame and I therefore cannot use ...
1
vote
1answer
48 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
31 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 ...
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1answer
28 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 ...
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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 ...