A programming language for OpenGL shaders.

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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?
1
vote
1answer
90 views

Strange artifacts when using gl_FragCoord to access texels

I ran into a problem with using gl_FragCoord variable to access texels. The problem can be illustrated by following example: First I render a textured quad into texture of size (W, H) where W and H ...
0
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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 ...
3
votes
1answer
175 views

How do 2D volumetric lights work?

Context So in my current project (written in Java using LWJGL / OpenGL, so GLSL for shaders) I added lighting quite a few months ago, which was already an interesting challenge, having never done ...
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 ...
4
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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 ...
2
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0answers
106 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 ...
0
votes
1answer
108 views

Transforming normals along with vertex? (GLSL)

So, I got a model matrix (Via uniform variable) in the shader, is there any way to use the model matrix to transform the normal of a vertex that has been transformed with glm::transform/rotate? If ...
2
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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 ...
6
votes
1answer
465 views

How is Signed Distance Field Ray Marching implemented for a dynamic world?

I think I understand the basics of Signed Distance Field Ray Marching. You model your scene with a bunch of distance fields (such as these: http://iquilezles.org/www/articles/distfunctions/...
0
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1answer
637 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 ...
4
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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; ...
2
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0answers
48 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 ...
1
vote
1answer
373 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
55 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
69 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. ...
1
vote
1answer
129 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
0answers
55 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
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1answer
62 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 ...
3
votes
1answer
71 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 ...
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
vote
1answer
59 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 ; ...
2
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0answers
84 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 ...
2
votes
1answer
136 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
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1answer
247 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, ...
16
votes
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 ...
1
vote
1answer
62 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 ...
1
vote
1answer
114 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
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)...
0
votes
2answers
90 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 ...
1
vote
2answers
433 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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0answers
70 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 ...
4
votes
1answer
310 views

deferred tiled lighting

EDIT I have discovered that it does not seem to be the lighting calculation but the culling code because when i draw the lights without the culling it works perfectly. I have been attempting to ...
2
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1answer
122 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 ...
0
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0answers
71 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 ...
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 ...
0
votes
1answer
41 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 ...
0
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0answers
32 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 ...
0
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0answers
33 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
52 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' ...
3
votes
1answer
102 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 ...
2
votes
1answer
554 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.
0
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1answer
149 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 ...
6
votes
1answer
200 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
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1answer
168 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
97 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
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0answers
67 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 ...
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: ...