A programming language for OpenGL shaders.

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4
votes
1answer
433 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 ...
0
votes
2answers
374 views

HLSL's Tex2D for GLSL?

I am trying to port a HLSL shader to GLSL. I'm just not quite sure how to convert this line: outA += Input.Color.a * tex2D(s, Input.TexCoord.xy + float2(-4.0 * pxSz.x * blurSize,0)).a * 0.05; ...
0
votes
1answer
1k views

GLSL - Declaring global variables outside of the main function scope

Does it help to declare variables outside of your main function scope in GLSL? Do these variables actually get reused and is it more efficient? Here is the code in question: varying vec2 vposition; ...
3
votes
0answers
441 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
217 views

GLSL: define a constant for both vertex and fragment shader

I have a constant for defining an array in the vertex shader. I want to use this constant also in the fragment shader to define another array of the same size. Naive attempts fail (simply use the ...
6
votes
1answer
756 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
0answers
165 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 ...
7
votes
2answers
261 views

Diffuse Reflection confusion

From what I've read, with a simple directional light, the color of a point, if you only take diffuse reflection into account (intensity = 1), should be color = color_of_point * color_of_light * ...
3
votes
2answers
75 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
220 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 ...
5
votes
1answer
2k views

GLSL default shaders

I've been arming my engine with error checking code. I'll try to describe this situation to my best abilities. Whenever i load a shader and there's an error (file doesn't exist, compilation error, ...
1
vote
3answers
1k views

OpenGL tile rendering

Currently I'm trying to render a TileMap using OpenGL 2.1, GLSL 1.2. I would like to draw every tile in just one draw call. I use a single texture with all tiles, identifying each one by an index. ...
0
votes
1answer
214 views

VBO in a class doesn't draw when The class has a destructor

I am making this class QuadTemplate class QuadTemplate { public: QuadTemplate() { vbo=0; uvbuffer=0; vao=0; TextureID=0; vboType=0; ...
7
votes
2answers
6k views

GLSL Shader - Change Hue/Saturation/Brightness

I'm trying to change the hue of an image using a GLSL fragment shader. I want to achieve something similar to Photoshop's Hue/Saturation Adjustment layer. In the following image you can see what I've ...
3
votes
2answers
3k views

Rotating an object when the center in not the origin - opengl

I'm beginning with GLSL and I learning the basic, I am using glm to do the matrix calculations at this point everthing ok,the problem is how I can move the origin to the center of my object, not the ...
3
votes
1answer
283 views

Directional light shader not behaving as expected

I coded my first glsl shader which manage diffuse and specular effects of a directional light. This is the fragment shader. #version 120 //matrix uniform mat4 model_matrix; //directional light ...
1
vote
0answers
144 views

Matrix array doesn't seem to get populated

I'm trying to stream an array of matrices to a vertex shader, but it seems that only the first matrix works. What could be the problem? I suspect that I upload the matrices in a wrong way. C# ...
3
votes
1answer
754 views

Incorrect GPU skinning

I'm having some problems with implementing skinning and skeletal animation. It seems that the skeleton and the mesh are loaded correctly, but the mesh gets funky when the bone transformations are ...
4
votes
2answers
2k views

Using two shaders instead of one with IF statements

I've been working on porting a relatively large opengl ES 1.1 source to ES 2.0. In OpenGL ES 2.0 (which means, everything uses shaders), I want to draw a teapot three times. The first one, with a ...
3
votes
1answer
277 views

Do GLSL 4.x subroutine variables cause any performance overhead?

There's not too much deep information about them on the web. How are they implemented and how they work under the hood? I'd like to know that they cause any performance overhead or not, especially in ...
0
votes
1answer
78 views

Vertex and Fragment Shader worldNormal

How to access/calculate worldNormal in a Vertex and Fragment shader ? Thanks a lot !
11
votes
2answers
8k views

How can I create an efficient bloom shader with GLSL?

I have searched the net for resources related to rendering a bloom effect using GLSL, but haven't found anything. Although the tutorial at Philip Rideout's website is a good one, it performs very ...
4
votes
2answers
1k views

GLSL Atmospheric Scattering Issue

I am attempting to use Sean O'Neil's shaders to accomplish atmospheric scattering. For now I am just using SkyFromSpace and GroundFromSpace. The atmosphere works fine but the planet itself is just a ...
0
votes
1answer
324 views

GLSL: Strange light reflections

According to this tutorial I'm trying to make a normal mapping using GLSL, but something is wrong and I can't find the solution. The output render is in this image: Image1 in this image is a plane ...
2
votes
1answer
197 views

Shader Variable Types

I have a simple question. what are the meaning of : half4 myHalf; myHalf.yyyy; myHalf.xxzz; // or myHalf.yw Thanks a lot !
2
votes
1answer
555 views

How to do directional per fragment lighting in world space?

I am attempting to create a GLSL shader for simple, per-fragment directional light. So far, after following many tutorials, I have continually ran into the issue: my light is specified in world ...
4
votes
1answer
284 views

Better solution for boolean mixing?

Sorry if this question has been asked in the past, but searching Google and here didn't yield relevant results, so here goes. I'm working on a fragment shader that implements both conditional/boolean ...
0
votes
1answer
218 views

bump mapping with 2 normal maps

I was wondering if its actually possible to do bump mapping with 2 normal maps... I have tried doing it this way however I get a function overload on max and dot. uniform sampler2D n_mapTex; uniform ...
1
vote
1answer
1k views

Volumetric Fog Shader - Camera Issue

I am trying to build an infinite fog shader. This fog is applied on a 3D plane. For the moment I have a Z-Depth Fog. And I encounter some issues. As you can see in the screenshot, there are two views. ...
3
votes
1answer
727 views

TBN Matrix : Eye vs. World Space Conflict

I am tired of misleading and insufficient articles making me more confused each time I read, I need a clarification that will solve my TBN matrix problem forever. Each article I read informs me ...
0
votes
0answers
350 views

GLSL gl_ModelViewMatrix breaks my code?

So I have the following shaders which work (to the extent that they are completed anyway). //Vertex Shader uniform float offset; void main() { gl_TexCoord[0].t = gl_MultiTexCoord0.t; ...
2
votes
1answer
231 views

What is the interval of fragment-shader code execution?

Without any intended delay, is the code of a fragment-shader run once per frame? If not, how often will the code be executed? (I'm new to shaders: I'm talking about glsl if it makes any difference)
0
votes
1answer
192 views

Shader program compiles fine on Ati, fails on other vendors

Got a real annoying problem here. My shader program compiles fine on my Ati Radeon HD card, but on Nvidia and Intel it failes to compile. Vertex shader: #version 120 attribute vec3 in_position; ...
1
vote
2answers
2k views

What is the best method to update shader uniforms?

What is the most accepted way for keeping a shader's matrices up to date, and why? For example, at the moment I have a Shader class that stores the handles to the GLSL shader program & uniforms. ...
2
votes
1answer
247 views

GLSL Multiple Uniform Structs

I'm developing a lighting system for my voxel game, and I have to send multiple (alot, say up to 200) lights to my shader program. Those lights contain the following data: Position (vec3) Color ...
2
votes
1answer
746 views

Simple Optimized Blur Shader

I have a vertex-fragment shader that use the Unity3D GrabPass functionality (it grabs the screen). And I apply my GrabPass to have a transparent effect. GrabPass { "_GrabTex" } sampler2D ...
4
votes
1answer
1k views

OpenGL GLSL skinning problem

This time I've decided to ask a question related to my skinning problem. Two earlier ones were not really related to my problem and I've deleted them. Ok, first of all, I'm using OpenGL 3, 3ds max, ...
-1
votes
1answer
168 views

OpenGL shader problem

So, I've been working on this game engine for a while now, and just the other day my friend tried running the program and his output doesn't match my output... My Program Output: His Program ...
2
votes
1answer
166 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 ...
0
votes
1answer
224 views

Get world-position in Vertex shader

I'm wondering how I can get the final position of a vertex. I use glTranslate in my render code, and I'm not getting the world-coordinates correct. My world is devided in chunks and my position get's ...
0
votes
1answer
287 views

GLSL Shaders-> How to manage?

As your game get's bigger and bigger, you will use more and more different shader effects. Let's take an easy example: I have clouds in my voxel-based world, and I want to give it a blue-ish tint ...
3
votes
2answers
304 views

Using a programmable pipeline in a game engine

As a learning experience, I'm developing my own 3D game engine using OpenGL. I'm a little confused as to how to implement my rendering engine such that it uses a programmable pipeline while still ...
3
votes
2answers
3k views

2D water shader similar to Limbo's effect

I'm wondering how I would go about creating a 2D water shader that is seen in this video http://www.youtube.com/watch?v=phChFfi4GOs The water effect that limbo uses is pretty awesome. I'm not so ...
0
votes
1answer
2k views

How to draw a circle with WebGL using GL_POINTS [closed]

I'm trying to draw a circle using simple vertices points and a big gl_PointSize value. I found this example and try to reproduce it on WebGL with no success.
-1
votes
1answer
123 views

Shader applied to Texture is not showed in GLSLES

I'm trying to learn the basic of shaders following basic tutorials in Ogre. I use GLSL ES 2.0 #version 100 I think I have a basic concept problem. I'm trying to render a model + texture without make ...
0
votes
1answer
102 views

Direction from the camera to the light source

I'm currently writing a game using OpenGL and GLSL. For the shader I need the direction from the current camera to the light source. The lightsource is given by lightSource.position as a uniform as ...
0
votes
0answers
321 views

Specular Light not working Phong shading

I want to implement Phong-Shading using GLSL. I also want to calulate all values using uniforms in the shaders. Nearly everything works fine, but there is an error with the specular term of the ...
1
vote
3answers
1k views

Set a variable inside a GLSL fragment shader that persists for the render

Is it possible to set a varying variable inside a fragment shader and have it persist? I'd like to use the depth component of the first fragment and use it on all the others, making the fragments all ...
0
votes
1answer
266 views

texture won't move OpenGL ES 2.0

I want be able to move my texture in GLSL I have set my texture to wrap S and wrap T but not sure why it wont move my fragment shader looks like this at the moment uniform sampler2D n_mapTex; ...
0
votes
1answer
145 views

texture movement stutters

Hey I at the moment I have got my texture to move however it stutters as I increment by 0.001 every second. My animation is done via FPS if that make sense and here is some code FrameCount++; ...