A programming language for OpenGL shaders.

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1answer
79 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 ...
2
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0answers
48 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
61 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
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1answer
62 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 ...
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1answer
169 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 ...
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1answer
55 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 ; ...
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0answers
61 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
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1answer
104 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, ...
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1answer
182 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, ...
15
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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 ...
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1answer
55 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
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1answer
87 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 { ...
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1answer
192 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 ...
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2answers
72 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 ...
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vote
2answers
342 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
64 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 ...
3
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1answer
204 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
105 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 ...
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0answers
67 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
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1answer
160 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 ...
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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 ...
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0answers
29 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 ...
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0answers
28 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
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1answer
45 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
79 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
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1answer
339 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
105 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 ...
5
votes
1answer
167 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
134 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
90 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 ...
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0answers
61 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
votes
2answers
186 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: ...
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3answers
263 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 ...
2
votes
1answer
227 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. ...
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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
146 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
256 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, ...
3
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0answers
89 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
144 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
102 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); ...
3
votes
1answer
143 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 ...
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votes
0answers
51 views

Pass uniforms to Filter's shader

I wanna implement this shader (https://www.shadertoy.com/view/MslGWN#) in PhaserJS state. So i transformed the shader to WebGL style. I overload Phaser.Filter's update function to pass iChannel ...
1
vote
0answers
42 views

glsl specular not working

ok, i'm a complete noob regarding shaders and all this, so i must be doing something really stupid, but i cannot get specular lighting to work. I've read a whole lot of different shaders on the ...
0
votes
0answers
17 views

Perspective divide: Why use the w component? [duplicate]

In OpenGL, I have read that a vertex should be represented by (x,y,z,w), where w = z. This is to enable perspective divide, whereby (x,y,z) are divided by w in order to determine their screen position ...
0
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2answers
97 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
0answers
86 views

Image speeds up while moving and or rotating instead of constant speed

I'm having a problem with rotating/moving an image. I've set one of my images to rotate on it's z-axis buy updating the angle, but when I run my game, the image starts slowly starts to rotate from a ...
0
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0answers
44 views

OpenGL, glDrawElementsInstanced behaving differently on NVIDIA GPU than AMD

I have an AMD GPU on my desktop, AMD HD 5770. I am working on a project on my desktop for over a year. In the scene, I have instanced grass and instanced trees. Everything is working fine on desktop, ...
2
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1answer
60 views

OpenGL ES God Ray Precision error

I have encountered the following (i think) precision error. (missing link need 10 rep) My source of inspiration was: (missing link need 10 rep) On the PC everything works fine, but on android it ...
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1answer
95 views

Create a “genie” effect in fragment shader GLSL

I have tried a while now to create a genie effect on a scrolling plane to emulate the background/floor from the Mad Hatter fight in Adventures of Batman and Robin (SEGA). Judging the way the 16 bit ...
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2answers
113 views

How do I start and stop a GLSL shader?

Is there a way to start and stop a shader?. I want to use this shader to sweep once over my texture and then stop. Does anybody know how to do that? void mainImage( out vec4 fragColor, in vec2 ...