A programming language for OpenGL shaders.

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3
votes
1answer
834 views

How do I create a jet engine exhaust effect with a shader?

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
0answers
92 views

dFdx and dFdy implementation details

I've been trying to understand the details of dFdx and dFdy since I'm trying to implement MSAA on a compute shader. The best description I've found is here: dFdx and dFdy on the cpu //T is any ...
1
vote
0answers
41 views

Consistent Shadow Map Filtering

I want to filter my shadow map generated by PSSM, but the problem is that I have a inconsistent filter size. The problem is that the shadow map sources rotate to find the best fit for the camera ...
4
votes
2answers
958 views

Aquire disassembly of shader code

Is there a way to get the disassembly that your driver generates when compiling a shader? I noticed that you can get an accidental disassembly dump if you go over the maximum thread group size ...
1
vote
1answer
107 views

Pixelation shader explanation?

I was looking for a pixelation shader for my postprocessing and came across this shader snippet - Works pretty well! - Not a whole lot of explanations on how it works except for "Pixelation is process ...
1
vote
1answer
41 views

sf::Shader not working properly on texture

I'm having trouble getting my sf::Shader to work on an sf::Texture that I've drawn myself. The vertex shader is pretty standard (I think it's just a copy of the example from SFML's page). The fragment ...
4
votes
2answers
63 views

Displaying smooth borders given a coarse grid-based map

I've been messing around with different algorithms trying to make a grid based map look smooth, I have tested with various shader based methods and wrote a few of my own but none of them look right. ...
14
votes
1answer
35k views

GLSL: How do I cast a float to an int?

In a GLSL fragment shader I am trying to cast a float into an int. The compiler raises an error: ERROR: 0:60: '=' : cannot convert from 'mediump float' to 'highp int' I tried raising the precision ...
1
vote
1answer
48 views

Shader and Texture Scrolling depending on Direction

I am trying to scroll a texture using its uv in Unity but I don't get the result I need. The aim is to have two components, the speed and the direction. I would like to define the direction in ...
3
votes
1answer
55 views

GLSL uniforms are returning -1, but they are being used in output

I have looked this up, and found some answers and people said that if uniforms aren't important to the final output than they get thrown away by the compiler. However, in my case they are being used ...
2
votes
0answers
39 views

Virtual infinite plane in shadow map

I have a WebGL deferred rendering pipeline, where I'm rendering shadow map with VSM technique. The goal is that the scene, or model, is hovering in space, and in addition to casting shadow on itself, ...
2
votes
1answer
57 views

Directional Light shadow mapping error - opengl

i need some help with shadow mapping (directional light) in opengl 3.3 and GLSL. The problem is that the shadows are not displayed correctly over de 3d models and primitives: This is the code that ...
0
votes
1answer
134 views

change position/orientation of a bone using assimp

I have been using assimp to import rigged models and animations. I followed this tutorial for skeletal animation and I have got it done properly. The part that I am trying to do now is to orient a ...
1
vote
1answer
52 views

why doesnt this function work? glsl opengl c++

Im trying to move a transformation matrix onto the gpu, and I managed to find this code to help me on the way: vertex.shader: #version 410 core layout ( location = 0 ) in vec3 vertex_position ; ...
0
votes
1answer
40 views

Modify Element of Struct Array

I have this struct array in GLSL. struct Test { vec2 value1; vec3 value2; float value3; } uniform Test u_test[5]; How can I modify the elements of this array one at a time? I know that ...
2
votes
1answer
83 views

GLSL Unsigned Int Values Not Retrieved Properly

I have packed several values needed for shading a particular vertex into a single 32-bit uint. In the shader, it is unpacked like this: vec3 color; uint vertexData = data; float sunlight, ...
0
votes
1answer
124 views

Help me understand this vbo/rotation, and how its done opengl c++

Im pretty new to opengl, and I just cant figure out how to rotate this vbo/vao in 2d space. This is how I bind my coordinates: float points[] = { 0.0f, 0.10f, 0.0f, -0.10f, -0.10f, 0.0f, ...
5
votes
1answer
634 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
40 views

Understanding webgl min/mag filter texture artifacts in orthographic projection?

Summary Flickering and shimmering of image plotted on a geometry where the viewport exceeds the size of the screen. I am using an orthographic projection for the camera. In this case, it is tied to ...
0
votes
0answers
36 views

Invalid GLSL on some machines

I'm writing a game engine using OpenGL 4.3 using gcc 5, mainly to teach myself graphics programming. Initial development was on my Surface Pro 3 using mingw-w64 and worked like a charm. I've decided ...
7
votes
2answers
349 views

Why does accessing a uniform float make my shader more than twice as slow?

My fragment shader was significantly slowed down by a recent change, and I've been trying to understand why. I isolated the main slow-down to accessing a single particular uniform float. If I include ...
1
vote
1answer
51 views

View Matrix to Texture Matrix

I'm converting view coordinates to texture coordinates for both my shadow maps and Screen space reflections. I keep seeing this conversion in examples: var T = new Matrix { ...
1
vote
1answer
786 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 ...
0
votes
0answers
154 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. ...
0
votes
2answers
52 views

Shader value remap - Blend Falloff

I would like to know if there's a way to remap a value that goes from 0 to 1 constantly like this. Into those values (those are examples). This might be some function transformation but I can't ...
0
votes
2answers
246 views

Textures rendering upside down and small with Pixel Shader in Mono Game but not XNA

I'm new to HLSL, attempting to use MonoGame to do some simple post processing effects. Here is my HLSL file, taken from one of rbwhitaker's xna tutorials (I would post the link, but can't post more ...
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vote
0answers
53 views

Converting glsl shaders

I need to convert these shaders from #version 400 core to #version 130 successfully but for some reason when I do it my models are not rendering properly when I load more then one type and I cant find ...
0
votes
1answer
128 views

Can i use shaders in allegro without opengl?

I'm currently learning opengl but it seems quite complicated so i considered using some library like sdl or allegro. I noticed that allegro has some built in functions to create and attach shaders. ...
0
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0answers
65 views

Color bleed ZX Speccy style

When having fun writing an imitation shader of attribute clashing on the ZX Speccy in OpenGL 3 and some fancy shaders, but I can't seem to think of an eficcient way for creating the attribute block ...
0
votes
0answers
27 views

Pass custom data rather than vertices/indices to GPU?

(For reference, I'm using OpenGL 3.3, core profile.) I'm attempting to render a decent number of 2D quads on the screen. Each quad is different, and a GLSL shader does all of the work of rendering ...
22
votes
1answer
17k views

in/out keywords in GLSL

I don't really understand how to use the in / out keywords in GLSL, and google is being uncharacteristically unhelpful. What exactly do they do? How would I use them if, for example, I want to pass a ...
0
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0answers
22 views

Opengl - atomicMin/atomicMax issues

I have my compute shader and it compiles fine, but when linking I get an error stating "too many uniforms are used in this shader". Weirdly enough when i remove two lines of the code the shader ...
1
vote
1answer
41 views

Bloom only colors with at least one value equal to 1,

I want to bloom/blur any color that has a 1 in it, like (1,0,0) and (1,0,1) etc. The script bellow blooms any color over a threshold, but what I want blooms only specific colors. 'Selective bloom' ...
2
votes
1answer
154 views

GLSL: #define vs const

What is the difference between #define NAME VALUE and const int NAME = VALUE in GLSL 410 core? As far as I can see, they both create a constant integer.
3
votes
1answer
65 views

Do shader compilers typically know not to look up unused texture channels?

I have a texture that's from the color attachment of an FBO in OpenGL ES 2.0, so I have limited control over the number of channels in the image. Suppose I only need the color from the R channel of ...
0
votes
1answer
86 views

Draw cube in glsl shader

I am working on a voxel engine. Currently my cubes are rendered as vbos. I thought, it may be better to load only the cooridinates of voxels to the shader and make it draw a cube itself. Can someone ...
1
vote
1answer
547 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: in this image is a plane with ...
5
votes
1answer
141 views

Dual paraboloid shadows on GLSL

I'm trying to port an XNA example to OpenTK + OpenGL, I found it here http://graphicsrunner.blogspot.com.es/2008/07/dual-paraboloid-shadow-maps.html But I'm having a really hard time, I think my maps ...
3
votes
1answer
105 views

Underwater Shader Animation Help

I found an underwater (distort) effect and I got it to work but somehow I cannot make it animate given the offset here: Fragment Shader code: uniform sampler2D fbo_texture; uniform float offset; ...
3
votes
1answer
80 views

Strange depth map projection

I'm trying to implement depth-only SSAO and for that, I render a depth map into a texture and pass it to my SSAO shader which then uses it. The problem is that when I try to output the depth map ...
1
vote
0answers
54 views

Set Render Target usage

I am using Unity and I have some difficulties about understanding the way Set Render Target works and how it can behave with the shaders. Is it possible to render a shader pass in multiple render ...
1
vote
3answers
186 views

OpenGL, GLSL, Modify Background Fill via Fragment Shader

I have noticed that fragments rendered by the glClearColor() method do not pass through shaders. However, I'd like to modify these fragments using my fragment shader. Is there any way of forcing them ...
1
vote
0answers
114 views

Blending Lightmaps and Dynamic Texture Shadows in HLSL/GLSL

I'm using Gile[s] as my lightmapper and my engine can execute GLSL/HLSL scripts. I would like to accomplish something like this for performance reasons. I was told that this technique can only be ...
1
vote
2answers
46 views

Problem passing variables in fragment shader

I'm trying to pass a point light from an array to a CalcLight function in a fragment shader. It works when I hard code in the value, but not when I use a loop. Here's the code: #define TOTAL_LIGHTS ...
2
votes
1answer
104 views

Stencil buffer VS conditional discard in fragment shader

I have a continuous height-mapped mesh to represent landscape. I also have 1 to let's say 10 wells on this landscape represented by additional models. What I want to achieve is to create an illusion ...
1
vote
3answers
171 views

GLSL shaders work when hardcoded, not when loaded from file

I am trying to learn OpenGL. I have a main.cpp where I create the vertex and fragment shaders as strings, compile and link and it works fine. When I try to load the identical shaders from text files, ...
0
votes
0answers
193 views

Transparency in GLSurfaceView

I'm new in game development. I have a view using GLSurfaceview and call in MainActivity. i want to make transparent that view. i have tried setZOrderOnTop() method in MainActivity and glClearColor() ...
3
votes
0answers
87 views

Raymarching tangents

I've recently started to experiment with raymarching over on shadertoy.com. It seems common to find the normal for a distance field like so: vec3 scene_normal(vec3 p) { vec3 e = vec3(0.001, 0.0, ...
1
vote
1answer
105 views

Cubemaps turn black OpenGL GLSL Java LWJGL

Recently I tried to add cubemaps to my 3D-rendering engine. The objects with a cubemap now turn completely black. This is how I load my cubemap: public static int loadCubeMap(String filename) { ...
0
votes
1answer
84 views

Processing through multiple shaders (LWJGL/Java/OpenGL)

Very simple question: Is it possible to process a vbo through different shaders? If so, how? What I want is sth like this: reflectionShader.bind(); //starts shader reflectionShader.load(some_values); ...