A programming language for OpenGL shaders.

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1answer
34 views

How to use a buffer in GLSL to do a LUT-lookup?

I am currently on a medical application which needs different kinds (up to totally individual) lookup tables (LUT) for image display. And this done with 10bit finish. So it is most of the time ...
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12 views

converting HSLS gives error

I'm using the following parser: https://github.com/unknownworlds/hlslparser I also have the following code: /* * Bo Sun, Columbia University, All rights reserved * ...
1
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1answer
45 views

Calling Shader Functions Inside Other Shaders

I'm new to OpenGL and GLSL, and bit confused about calling conventions of shader functions. I'm trying to implement various procedural noise algorithms in GLSL. I'd like to have separate files for ...
1
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1answer
60 views

Dot based light mask with shader on sprites

So I have a scene, completely based on 2D sprites. I want to render "light sources" into a seperate frame buffer (so mostly dots around, for example, the centre of a flame) and then render that frame ...
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12 views

Invalid operation (1282) in GLSL vertex shader

My GLSL vertex shader works fine, but you if put a for loop inside or rename the uniform xxx to something else, it says the follwoing: Exception in thread "main" org.lwjgl.opengl.OpenGLException: ...
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24 views

Strange result, when changing variable name

I have no idea, what is going on. The mat4 xxx is the cause. Renaming it to "bones"/"bone_transfromations" etc. won't work it gives me an error. Renaming it to "test" works perfectly fine... This is ...
3
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1answer
69 views

What are the advantages of tangent space shading/lighting, and what about attenuation?

In several topics here it was suggested by people that doing lighting in tangent space is better than doing it in world space. Right now I am doing it in camera space, but it's really similar to world ...
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30 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 ...
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2answers
46 views

glsl uniform int as index of const array

I have a const array that define a few materials for directionnal light. I'd like to change the material using an uniform int as index of that array. Doing that leads to severe framerate drop. I know ...
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0answers
36 views

loading a model, which has multiple meshes using assimp

I have been using Open Asset Import library(assimp) along with OpenGL API to load and render 3D models. I followed some tutorials and have got the output as expected. But, I have failed to understand ...
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0answers
29 views

Achieve SSAO with deferred rendering,GLSL

I'm trying to add SSAO effect to my engine and it doesn't look as it should. To achieve this effect I based on this article. I'm using also deferred renderer so I entered some modifications: ...
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2answers
44 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 ...
1
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1answer
54 views

OpenGL Post Processing Introducing Artifacts on Certain Systems

Playing around with God-Rays in my framework, I was greeted with the following artifacts on my laptop: The artifacts themselves act almost like noise, flickering around the image rapidly. They also ...
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0answers
29 views

Motion Blur (as per GPU gems article) only considers camera rotation, not translation

I am following this article and have implemented it exactly as described: http://http.developer.nvidia.com/GPUGems3/gpugems3_ch27.html The problem is that things are only blurred when the camera is ...
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2answers
88 views

How can I optimize these GLSL bitwise operations?

I need the following part of my vertex shader simplified. Sb=Sb|((gl_VertexID&(128+1))<<9); Sb=Sb|((gl_VertexID&(512+4))<<6); Sb=Sb|((gl_VertexID&(2048+16))<<3); ...
3
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1answer
113 views

If-clause in GLSL

I read a few thing about, that in GLSL both sides of the if-clause is executed, so do you have any idea for a workaround for this one: uniform int uses_bones; uniform mat4[] bone_transformations; ...
1
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1answer
36 views

OpenGL/GLSL/LWJGL return value from shader

I'm trying to do some bone animation. I don't want the whole skeleton to be loaded to the GLSL shader every time, even tough it's not needed, because one vertex is parented to one bone, not more. My ...
1
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1answer
53 views

Can drawing to an FBO be done purely with a depth input texture, or do I also need a color attachment?

I am trying to implement Exponential Shadow Maps and I've got it almost working. The part I am stuck on is the "optional" separable Gaussian blur of the depth map to give soft-looking shadows. I am ...
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0answers
28 views

GLSL billboarding

I want to make billboarding using GLSL. For what I've got so far it works, but not exactly the way I want. My vertex shader looks like this: #version 120 uniform float partSize; varying vec2 ...
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0answers
38 views

Trying to get the fragment shader to output a list

I am trying to figure out a way to get the Fragment Shader to output a list of gl_VertexID-s. I want to use the GPU to get a list of vertices in the viewing frustum. Is there any way I can get a ...
1
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1answer
69 views

Averaging normals, or tangents

I am using a library to load an obj but it doest compute the tangets for each vertex, which I need for normal mapping and pom. I computed my tangets, and bitangents, everything appears to be fine, but ...
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0answers
53 views

2D GLSL Lighting and Sprites

I'm trying to make a 2D game engine, and I really want to support ambient light as well as multiple point lights that you can define the color, intensity, radius, etc from uniforms in glsl shaders. ...
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0answers
66 views

glGetUniformLocation returns 23724032

as the title says, I have a problem using glGetUniformLocation call that returns, for the following code, the value 23724032. I'm writing a little engine and the draw function of my models is: void ...
2
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1answer
57 views

What will happen if the argument of mix() or clamp() is above 1 or below 0?

There's two magnificent intrisincs: mix() in GLSL and clamp() in HLSL, which are used to implement linear interpolation. Let's say we have a variable: float v = ?; // where ? can be [-FLOAT_MAX, ...
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53 views

What limits the number of vertices the GPU can process per clock cycle?

I am currently experimenting with OpenGL to make my own game. I wrote some test code to see what are the limits of my GPU. I own a Geforce 840m. This essentially consists of a draw command ...
0
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1answer
84 views

Java, Crashing with a Shader on Intel HD Graphics

I just got a new computer (Acer Aspire ES1-311) which has an integrated Intel HD Graphics card, and I noticed that this fisheye shader crashes my game (LibGDX game, VM Crash): varying vec2 ...
0
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1answer
48 views

Getting the real fragment depth in GLSL

I am trying to write a simple GLSL shader that just renders the real (not normalized) depth of a fragment as a floating point value. So far, I've figured out how to get the depth of a vertex, and ...
0
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0answers
57 views

SFML - Rendering a torch with a fire animation [duplicate]

I have coded a 3D maze simulator in SFML using raycasting. However, I want to add a torch to the screen, so that the lighting seems more realistic. From my understanding, I would have to use ...
1
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1answer
82 views

How does an energy-conservative Blinn-Phong-Fresnel model work?

What is a plausible, basic equation/pseudo-code for energy-conservative Blinn-Phong shading, including Fresnel with a coloured light-source? The net gives so many alternatives that it's hard to ...
1
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1answer
75 views

How can I make this shader background more efficient?

I want to use a shader as a background for a mobile game. I'm using libgdx for my project. I've never written glsl before, but here's my attempt so far: http://glslsandbox.com/e#22332.13 On desktop ...
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0answers
76 views

C++ - SFML - OpenGL - GLSL - smooth waving texture

I have this shaders: Fragment: uniform float time; uniform sampler2D texture; void main() { float t = time; vec2 aux = gl_TexCoord[0].xy; // This would also make waving/deform the ...
0
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1answer
47 views

GLSL: Incompatible Types at Initialisation (and no available implicit conversion)

I'm recieving the following error when compiling my GLSL shader: Incompatible types in initialization (and no available implicit conversion) It occurs on line 94: int shadowMap = ...
0
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1answer
37 views

Opimized lineral to sRGB glsl code

Currently I use simple and ugly implementation of lineral -> sRGB transfrom float sRGB(float x) { if ( x <= 0.00031308) return 12.92*x; else return 1.055*pow(x,(1/2.4) ) - 0.055; } vec3 ...
0
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0answers
27 views

Encoding Floats to RGBA and Blending causing artifacts

I am using float packing to encode a float value inside a RGBA texture because I don't have access to float texture unfortunately. Here are the function I am using for encoding and decoding. inline ...
1
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0answers
58 views

Uniform Buffer Binding-points

I believe Uniform Buffers/Blocks has been the hardest thing to grasp in OpenGL. Hopefully this will be my final issue regarding this. I have created a uniform buffer that contain data of Light ...
0
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1answer
44 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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0answers
50 views

Assimp - generate tangents and bitangents

I have started using Assmip 3.1.1 in my OpenGL application. Let's consider a simple example. Here is obj triangle model: mtllib triangle.mtl v -5.0 0.0 0.0 v 0.0 0.0 0.0 v 0.0 5.0 0.0 vn 0.0 0.0 ...
0
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1answer
65 views

Render model with meshes with materials and/or textures

I'm making a model class that is using Assimp in the background. I want my models' meshes to be able to have a material and an optional texture on top of that. Right now I'm doing it like this: for ...
7
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1answer
517 views

How to implement this kind of ripples with a GLSL fragment shader?

So I have already implemented the reflection part: uniform sampler2D texture; uniform vec2 resolution; uniform vec3 overlayColor; void main() { vec2 uv = gl_FragCoord.xy / resolution.xy; if (uv.y ...
0
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1answer
58 views

Cubemap faces rotation in GS shader

I Can't get correct rotations for cubemap faces. Thats should come to geometry shader, from camera "view" matrix I want make 6 faces for my cubemap, but seems I can't get it correctly... My first ...
0
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1answer
126 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(); ...
1
vote
1answer
78 views

How to calculate reflection vector from point sprite sphere?

So far I achieved building a cube map following this tutorial. Then I drew three points using glDrawArrays(GL_POINTS,0,3) and calculate the normals based on a sphere. To compute the incoming light ...
0
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1answer
93 views

Fragment Shader output type error

StackExchange! I've been working with opengl for a bit and I'm trying to finally load the shaders instead of having them inline. I'm having a ton of issues, though. As soon as I solve one, another ...
2
votes
1answer
51 views

Failing to move exponential depth term to depth shader in exponential shadow mapping

I'm playing around in my little toy project to see if I can understand how exponential shadow mapping works. To begin, I have the following two fragment shaders: Light depth texture shader ...
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votes
1answer
59 views

how to turn (or solidify) water or fuild into solid material (Renderring Effect)

i want to implement an effect like this. for example, let's assume the clay are made of particles. liquids of clay flows for a while, then it becomes dry and rest.finally those particles becomes only ...
4
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1answer
342 views

C++ OpenGL ShadowMap Issue/Artifacts

I am currently implementing basic shadow mapping in my C++ Custom Engine using GLSL 4.10. It is currently working with basic PCF anti-aliasing and very minimal reduction for unwanted artifacts. Here ...
0
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1answer
69 views

Reconstruct shader vertices in OpenGL

I'm not sure if 'reconstruct' is the correct term for this but essentially what I am trying to do is calculate vertex positions (that are already calculated via shader) on the CPU for the purpose of ...
0
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1answer
94 views

Grayscale and 2D lighting using cocos-2dx

I want to create a lighting effect on a gray-scaled world using cocos2d-x. What I've done is creating a layer which runs a shader program that receives light positions and radiuses as input and ...
0
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2answers
53 views

Overload how an object instance of a class is treated when used

So I've made this struct that encapsulates a glm::vec4. This is because vec3s are treated as 16-byte in GLSL, but I don't want to assign a vec4 if I only really need 3 components. Anyway, my question ...
0
votes
1answer
68 views

Ray casting problem using JOGL

I'm trying to port an old perfectly functioning ray casting implementation from my lwjgl project (FF pipeline) to a new project using JOGL and shaders. My problem is that my ray no longer intersects ...