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
37 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
297 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
47 views

Shadow mapping bone animated model

I am trying to get shadowmapping right for my animated models. It works perfectly for static meshes but the animated models are just wiggeling a bit here's the vertex shader for rendering to the ...
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0answers
33 views

What game engine should I use? [on hold]

Okay before I go any further I have worked with other engines before like unity and attempted to learn the new unreal 4. The game I would like to make is an adventure game with a wide open world and a ...
0
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1answer
27 views

glRotatef not rotating simple 2D triangle

I am new to OpenGL and am learning it for the purpose of some simulation that I am doing as part of my research work. I have been following the tutorials given at ...
1
vote
0answers
31 views

Can you trilinear sample a non volume texture?

Let's say that i have a regular 2d texture (not a volume texture). Is it possible to do trilinear texture sampling of that texture even though it isn't a volume texture in opengl or directx? ...
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2answers
87 views

GL_SPOT_CUTOFF not working properly

I'm new to OpenGL. I'm studying OpenGL 2.1 and I'm trying to make a little program to test the GL_SPOT_CUTOFF property, but when I set a value between 0.0-90.0, the light doesn't work and everything ...
0
votes
1answer
123 views

DirectX11 Equivalent of OpenGL code

I am currently porting parts of my engine over to D3D11 from OpenGL and was trying to figure out how I would accomplish the following blending functions in D3D11. glEnable(GL_BLEND); ...
8
votes
3answers
164 views

Using full resolution of depth buffer for 2D rendering

I'm working on a front-to-back renderer for a 2D engine using an orthographic projection. I want to use the depth buffer to avoid overdraw. I have a 16-bit depth buffer, a camera at Z=100 looking at ...
3
votes
1answer
270 views

How do I use unpackHalf2x16?

I'm trying to use (un)packHalf2x16, without success so far. I'm drawing with: glVertexAttribIPointer(0, 2, GL_UNSIGNED_INT, 0, 0); glEnableVertexAttribArray(0); glBindBuffer(GL_ARRAY_BUFFER, vbo); ...
1
vote
2answers
92 views

OpenGL Vertex Array Object(VAO)

I have drawn a triangle and a square using open gl and everything was fine. I have then tried to draw the same triangle and square, while implementing VAO's and now I only get a white triangle - ...
2
votes
2answers
110 views

Lasers in 3D space game

I am creating this little 3d space shooter and am somewhat unsure on how to implement the laser beams. I'm thinking about something along Star Wars and the like where mostly you shoot rather short ...
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1answer
62 views

Incorrect Normal Matrix

In my game engine I'm passing a normal matrix to my shaders like so: Matrix3f normalMatrix = modelMatrix.invert().transpose(); However this is causing lighting to rotate with my object, producing a ...
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votes
1answer
23 views

useful way for coloring 3ds object in opengl

I have been working in making plane in blender and it has many materials over than 90 , and now I need it in an opengl project with c++ , but as you know if I but the 3ds file the plane color is ...
0
votes
0answers
13 views

Adding a 2D transformation matrix to GLSL

I'm having trouble understanding the matrices I need to render an object in OpenGL. I've been using a matrix to make up for the translation and scaling from the camera in my game but I didn't have a ...
1
vote
1answer
129 views

Problems with texture orientation in space

I am currently drawing texture in 3D space and have some problems with it's orientation. I'd like me textures always to be oriented with front face to user. My desirable result looks like ...
0
votes
1answer
44 views

Rotate heading relative to agent's local space

I'm having a little trouble translating a point in my game's world space to an object's local space. I have a cannon in my game with a normalized heading vector that's always supposed to point in the ...
1
vote
0answers
27 views

Find camera coordinate of vanishing point

Given a vector and a camera (position, angle, up vector, field of view, etc), how would I find the vanishing point of the vector in camera space?
5
votes
1answer
15k 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 ...
0
votes
1answer
127 views

OpenGL Shader Storage Buffer Objects array length problem

Ok guys, I think I have a very strange problem. I have an old laptop, but its HD 6370M currently supports opengl 4.4, so i decided to learn how to use some new features of this platform, so after ...
15
votes
7answers
2k views

For 2D games, is there any reason NOT to use a 3D API like Direct3D or OpenGL?

I've been out of hobby Game Development for quite a while now. Back when I did it, most people used Direct Draw to create 2D games. By the time I stopped people were saying OpenGL or Direct3D with ...
7
votes
3answers
1k views

What is the contents of the buffer *after* a call to glSwapBuffers()?

(SDL_GL_SwapBuffers() in particular) When you have drawn a scene, and you call swap-buffers, it is routine to then glClear() the scene before drawing anything; if you don't clear, what is the ...
2
votes
1answer
141 views

How to improve Batch Rendering to work with 3D skeletal animation data

I've implemented a batch rendering technique that is described in detail here: http://www.gamedev.net/page/resources/_/technical/opengl/opengl-batch-rendering-r3900 I'd like to extend it now to ...
0
votes
2answers
37 views

How to set black borders in rubik cube using opengl GLSurfaceView android java

I am new in android game development.I have a problems to set the cube face color with black border. public void setupSides() { int i, j, k; // Paint back blue i=0; for(j=0; j<dim; j+=1) { ...
2
votes
2answers
109 views

Translating an object in the rotation direction

I am creating a graphical scene with OpenGL and SDL, and I'm running into a problem in regards to translating an object in its rotation direction. Each of the graphical objects in the scene has a ...
0
votes
2answers
70 views

PBR Metalness Implementation: specColor at Value 1?

I am doing a BRDF supporting the metalness/roughness workflow. I know that in cases of Metalness = 1.0 the reflectance value is taken from the albedo map - so is the specular color to tint the ...
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vote
2answers
76 views

GLFW / OpenGL location and size in pixels

I'm using GLFW to create a little game. (and by little, I mean: small, nonprofit) After a while of puzzling, I found out that this draws a texture (from an image, for instance) to the screen: (the ...
0
votes
1answer
40 views

Free camera rotation in 3D space

I'm using a view matrix to do camera movement and rotation. viewMatrix = new Matrix4f(); viewMatrix.setIdentity(); Matrix4f.rotate((float) Math.toRadians(rx), new Vector3f(1,0,0), viewMatrix, ...
3
votes
0answers
128 views

Skeletal animation in OpenGL

I'm using Assimp to do skeletal animation in my OpenGL application. I used Blender to export this one-boned model to a COLLADA file: The model has only one bone, called arm bone, that controls the ...
2
votes
0answers
30 views

Cannot convert bitmap to texture

I'm doing a little C# / OpenGL project and I can't manage to load textures properly. So here is my texture class : public class Texture { public String Filepath; private int TextureID; ...
0
votes
0answers
36 views

Transparency in GLSurfaceView

I am new in game development .I have a class which extends GLSurfaceview and we add this class in xml file and that xml file pass in main activity i want to make transparent that class. we already use ...
1
vote
1answer
230 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 ...
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votes
1answer
35 views

Java libgdx get clicked square without iter

I would like to detect which square is clicked without iterating over all elements! i don't want to do this anymore for all elements. if( x >= this.getAnchorX()-HalfWidth && x <= ...
1
vote
0answers
41 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 ...
7
votes
1answer
4k views

Interleaving Arrays in OpenGL

In my pursuit to write code that matches todays OpenGL standards I have found that I am completely clueless about interleaving arrays. I've tried and debugged just about everywhere I can think of but ...
1
vote
2answers
339 views

Calculating shadowmap coordinates for cubemap in shading pass?

I'm trying to implement shadow mapping with cube maps. I believe I've done the first stage by filling the cube map, but for the final shading pass I am unsure how to exactly calculate the cubemap ...
1
vote
1answer
57 views

How to only render fragments with Z from 0 to 1 in OpenGL?

I have been using OpenGL for a year now, but I just recently found out that OpenGL only clips vertices when the absolute value of the x,y or z coordinate is less than the absolute value of w ...
0
votes
1answer
1k views

OpenGL Reconstructing Position from Depth

I know this has been asked a lot of time before but none of those answers fixed my problem. I try to implement deferred shading and to do so I need to reconstruct the world space position from the ...
0
votes
2answers
318 views

translate-scroll repeated 2d texture using opengl shader

I managed to implement an infinite 2d texture scrolling using the following shader. btw I'm using cocos2d-x 2.2.1. The vertex shader: attribute vec4 a_position; attribute vec2 a_texCoord; #ifdef ...
0
votes
1answer
26 views

wrongly scaled on cocos2dx 3.2 when render to multiple fbo (more > 1 deep)?

i have bug that only happen when retina flag disabled. i try draw multiple render texture to achive some multi post effect: so i have 3 render texture, fbo 1 for final pos effect fbo 2 for back ...
4
votes
1answer
251 views

Variance shadow maps don't want to render properly

I've implemented VSM (and also ESM) in my engine but results are for me not as I expected and saw in many examples published on network. I set filtering of shadow maps to GL_LINEAR but when I compare ...
1
vote
1answer
65 views

How to use multiple custom vertex attributes in OpenGL

My code currently uses glBindAttribLocation and glVertexAttribPointer to specify two custom vertex attributes in indices 6 and 7. This seems to work fine, but I wish to add another attribute and no ...
1
vote
1answer
64 views

Rotating a swinging sword in LWJGL gives wierd results

I'm making a 2d top down game in Java using LWJGL(OpenGL, essentially). I recently tried adding a swinging sword mechanism. My coordinate system is set to the bottom left FOR ALL objects. The rotation ...
2
votes
1answer
110 views

Rendering text with SDL2 and OpenGL

I've been trying to have text rendering in my OpenGL scene using SDL2. The tutorial I came across is this one Rendering text I followed the same code, and I get text rendering fine. However the issue ...
0
votes
0answers
24 views

In OpenGL on Android, how do I give quads a border color?

I am new to game development and I'm working on a Rubiks cube game in Android using OpenGL. I want to create a cube with black borders, but I can only manage to set the fill color: GLColor[] colors ...
0
votes
1answer
35 views

How to draw 2d above 3d scene?

I have an OpenGL(3.3)+GLEW application. I want to draw a black vertical rectangle at the left side of the window for writing some information on it, like fps (I use GLEW function for drawing text). ...
2
votes
1answer
141 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 ...
0
votes
1answer
54 views

Easy method of obtaining texture coordinates for sprite sheet

In my (OpenGL ES 2.0 Android) game, I use 2 types of Sprite Sheets. In one type all sprites/frames are of equal size and in the other they are all different shapes and sizes. It is the latter one to ...
0
votes
3answers
96 views

Editing the pixels of a rendered image

I want to render a simple OpenGL scene as usual, but then I want to superimpose a small image of my own (such as from a bitmap file) on top of the render, such that this image always shows. For ...
1
vote
2answers
34 views

glutPostRedisplay() is not redrawing after updating model view matrix

I am trying to change the rotation of my object with keyboards, when I move the object in the direction of x, y or z it is okay, it is responding correctly. But when I try to change rotation, it does ...