A programming language for OpenGL shaders.

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0
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0answers
71 views

How to properly use a 3D texture in OpenGL 4?

I working on a student project which consists to make clouds volumetric rendering and implement the feature in an existing engine based on OpenGL 4 and written in C++. To do so, I have set a compute ...
2
votes
0answers
65 views

GLSL shader with light colors wrong on nvidia optimus

So, I built some code to draw a spinning cube with a red light on the right side, and a blue one on the left. I run it on my laptop with optimus graphics, and on my desktop with nvidia. On the laptop, ...
3
votes
0answers
242 views

Schlick Fresnel Shader

I hope you are all doing ok. I have an issue with my Fresnel shader that doesn't allow the Fresnel to change as my camera moves around. I'm not sure what i'm doing wrong. I'm using glsl with the ...
2
votes
0answers
71 views

Physically-based BRDFs

I'm starting to implement a real-time PBR shading pipeline in one of my projects and had a few questions that I thought folks around here could help clarify. 1) Is it fair to say that in a PBR ...
0
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1answer
73 views

GLSL Shader not compiling (Android & LibGDX) and no log available

I'm trying to get a "ripple"-shader working for OpenGL ES 2.0+ (using LibGDX). However, I can't get it to compile, and for some reason ShaderProgram.getLog() returns an empty string even though the ...
1
vote
2answers
233 views

Unity, shader, vertexID

I'm writing a shader and I just wanna ask if it's possible to get the ID of the vertex that is currently being manipulated. I read something about gl_vertexID, but I couldn't find out if that is ...
1
vote
1answer
122 views

GLSL strange if statement problems

I'm trying to use if statement in my fragment shader. I want to compare my in int finalLightType[4]; Here is my vertex shader code and fragment shader code: Vertex: #version 400 core in vec3 ...
0
votes
1answer
84 views

Projection Matrix Breaks My Rectangle

This is my vertex shader, shown below. #version 330 core in vec3 a_position; in vec4 a_colour; // FOV = 70, near plane = 0.1, far plane = 1000 const mat4 u_projection = mat4( 1.428148, 0.0, 0.0,...
2
votes
1answer
307 views

equirectangular panorama rendering?

I want to render my scenes as equirectangular panorama frames. I can get the angular fisheye which is what I actually need by applying the rendered frame as a texture to a correctly UV mapped circle. ...
0
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0answers
59 views

SSAO attenuation problem

I followed this tutorial and I'm getting incorrect results for SSAO. My gBuffer seems valid. Here is a picture showing Ambient Occlusion, Normalized Depth, Normals in View Space and Position. ...
1
vote
1answer
95 views

Best way to find line segment intersection

I need to find the point of intersection between two line segments in 2D space. I receive them in terms of both coordinates of both lines. Because they are line segments I would also need to know if ...
11
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6answers
15k views

OpenGL ES 2.0: Repository of Quality Shaders [closed]

Could I kindly ask, to suggest me a repository of high quality OpenGL (OpenGL ES 2.0) vertex and fragment shaders, please? I am looking for pixel based ligting shaders (such as phong) and simmilar. ...
0
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2answers
270 views

How to wrap textures inside shader GLSL

I'm trying out GLSL and one of the problems I'm facing is wrapping a random texture sampler in the shader. Searching for answers on the web first, this leads me to using these commands: ...
0
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0answers
72 views

Modern OpenGL and SpriteBatching

I tried to find tutorials regarding SpriteBatch done in Modern OpenGL 3.0+, but failed to find any good resources so far. So can anybody please provide me a good resource/tutorial to achieve ...
0
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0answers
38 views

Issue with Use SSBO OpenGL

Students that use OpenGL. Do not speak English well. So please understand. There is currently a problem C++ Code Setup() : glGenBuffers(1, &ssboHandle); GLuint ssbo_binding_point_index = 0; ...
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0answers
39 views

LWJGL 3 GLSL normal problem

I have a pretty strange problem today. I started to make a 2d game yesterday, and everything was right until now. I wanted to make a lighting system, wich required me to send the vertexnormal from ...
1
vote
1answer
275 views

Raymarching on a Hi-Z buffer in GLSL

So I'm trying to implement Screen Space Reflections using a Hierarchical z-Buffer in GLSL. I'm following the approach from GPU Gems 5 and the Frostbite presentation linked here ("Stochastic Screen-...
-1
votes
1answer
47 views

OpenGL/GLSL matrix in uniform block confusion

I'm a bit confused about the proper way to send a matrix from my code (C++) into a GLSL shader. My matrix object is stored in row major format in memory. If I use the following shader code it works ok....
0
votes
2answers
126 views

Why does rotating my quad appear to move it farther away?

I have created a 3x3 matrix class which is then passed over to OpenGL Vertex Shader for transform my Quad. I have been trying to rotate my Quad around Z-Axis. Rotation is working but the Quad getting ...
24
votes
1answer
16k views

How do Raymarch shaders work?

I have been looking at shaders found here shadertoy.com and most of the cool ones have noise and raymarch in common. I do not understand the source code at all but I really want to. How do these ...
2
votes
2answers
1k 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 ...
0
votes
1answer
53 views

OpenGL: strange thing with depth and text rendering

TL;DR I render a scene with M,V,P matrices as always. Than I render something (in this case - text) without any matrices and using separate shaders pair on coordinates with Z = -1. Somehow it's ...
0
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0answers
70 views

Unity - _LightMatrix0 and Directional Light

I am trying to access the _LightMatrix0 in a forward base pass to calculate some light point of view coordinate but it seems that the _LightMatrix0 is empty with directional light. Any idea how can I ...
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votes
1answer
37 views

GLSL shaders in a program

I obviously don't want the client to be able to view/modify my glsl code. Does this leave me with only one option, and that's to hardcode it in my cpp files? How do you deal with this issue?
3
votes
1answer
182 views

How to deal with overlapping black parts of Light mask textures?

I am using this masking texture for a dynamic lighting effect in my game: It looks beautiful until two lights begin to overlap: This is obviously because the textures are overlapping when I draw ...
16
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1answer
2k views

Phong lighting - there is something very strange with specular lighting

I implemented Phong lighting. Everything seems to work - torus and spheres are lighted as expected, etc. But I notices something strange regarding specular lighting of directional light. Here are two ...
47
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6answers
25k views
-1
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1answer
162 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 ...
4
votes
4answers
2k 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 ...
0
votes
2answers
131 views

Passing data into a vertex shader for perspective divide

In OpenGL and GLSL, I am just learning about perspective projection and the vertex shader. However, I am a little confused about what data actually needs to be passed to the vertex shader, and what ...
0
votes
1answer
47 views

Using one GLSL shader program for textured and untextured rendering?

Rather than have two separate shaders in my OpenGL code (one for when a texture is bound, one for when none is bound) I usually go for one shader program which handles both. This is my usual fragment ...
4
votes
1answer
111 views

How do I do selective water surface rendering?

I have a shader that renders the "texture" of a very realistic water on a tile in the 3D world using a Frame Buffer. The problem is that, for example, I only want to render the part that isn't below ...
2
votes
1answer
123 views

Tiled deferred rendering light culling

I'm trying to implement tile based light culling in opengl using a compute shader. I am using this as a guide. The lighting calculations work fine but the point light culling doesn't seem to work any ...
4
votes
1answer
258 views

Rotate billboard towards camera

I'm trying to create a particle system in OpenGL, and as such I need to use billboards. I need these billboards to face the camera at all times. The tutorials I've been following only rotated the ...
10
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1answer
13k views

OpenGL/GLSL: Render to cube map?

I'm trying to figure out how to render my scene to a cube map. I've been stuck on this for a bit and figured I would ask you guys for some help. I'm new to OpenGL and this is the first time I'm using ...
3
votes
1answer
1k views

GLSL Core Functionality Geometry Shader examples

I'm doing some research on geometry shaders and am having problems finding code examples/tutorials that does not use one of the extensions introduced before it was core functionality of OpenGL 3.2. ...
3
votes
2answers
4k views

computing gl_FragDepth

I am trying to draw spheres using a billboard, so I have a normal map with a z component that I am sampling in my fragment shader. I just need to add this z component to the depth of my fragment to ...
6
votes
1answer
6k views

GLSL if-else statement unexpected behaviour

This question is related to this other one I asked a few days ago. Because I have finally get to the bottom of the issue, I have rather preferred to open a new question with a more detailed ...
21
votes
1answer
4k views

Why does this geometry shader slow down my program so much?

I have an OpenGL program, and I'm rendering a terrain mesh. I displace the vertices in the vertex buffer and don't really color them in the fragment shader yet. I'm adding a geometry shader one part ...
2
votes
0answers
108 views

Texture coordinates for custom geometry in SceneKit ios9

I am trying to texture the a custom plane shape I created in scenekit on iOS9. I need the texture to spread out and stretch over the entire surface. I have a vertex and fragment shader on an ...
2
votes
1answer
48 views

(GLSL) Lighting code outputting a black quad

So, ive been transitioning to modern opengl recently and it's going rather well. But alas, something must go wrong. As the titel says, all I'm getting is a completely black quad. (Ive double checked ...
3
votes
1answer
1k views

Alpha Blending: use the pixel with the smallest alpha

I'm writing a transparency shader where I need any intersecting textures to, wherever they overlap, take the texture pixel with the smallest alpha value and render only that, discarding the other ...
0
votes
1answer
105 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 ...
0
votes
1answer
638 views

Terrain shader from heightmap opengl GLSL

I generated a terrain from a heightmap and now I'd like to apply shader on it which can contain different textures, based on height but I can't adapt any online code to my project. This is the ...
1
vote
1answer
258 views

FAST position reconstruction from depth

I'm struggling a lot with reconstructing the world space position (or alternatively the view space position) from depth (by reading the depth buffer) in a performant way (in a full-screen post-process)...
4
votes
1answer
245 views

How to handle the birth and death of particle without reading from the buffer

I've implemented a simple particle system where each particle has a position, velocity, age and lifespan stored in different SSBOs. Most of the data including all the position, velocity and age is ...
4
votes
1answer
72 views

Shaders: packing 4 textures into a single RGBA - slower?

I'm experiencing something really strange on an iOS mobile device. I have 4 textures, and after some profiling it seems, that doing four separate grayscale texture reads is faster, than reading the ...
1
vote
1answer
34 views

How can I move the camera directly under a certain plane?

I am attempting to render a "reflection" of a scene for water: To create this illusion, I need to render the scene from below, and then ignore all geometry below the water line. As such, I need ...
2
votes
1answer
106 views

How to blur image using glsl shader without squares?

I want to blur image with Gaussian blur algorithm. And I use the following shaders: Vertex shader attribute vec4 position; attribute vec4 inputTextureCoordinate; const int GAUSSIAN_SAMPLES = 9; ...
1
vote
1answer
228 views

OpenGL 3.3+ Problem with ortho projection for UI/HUD

I have to a little bit of a problem with drawing HUD elements on top of my 3d world using a ortho projection. My 3D world keep getting render but there is nothing showing of my UI. I wrap the code ...