A programming language for OpenGL shaders.

learn more… | top users | synonyms

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 ...
2
votes
1answer
115 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
207 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
985 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
69 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 ...
7
votes
2answers
374 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
99 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
897 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
174 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
79 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
368 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 ...
1
vote
0answers
68 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
178 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
votes
0answers
68 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
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 ...
0
votes
0answers
31 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
47 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
418 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
89 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
123 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
574 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
180 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
144 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
91 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
63 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
291 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
130 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
49 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
168 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
284 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
votes
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
159 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
109 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); ...
0
votes
0answers
53 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
2answers
255 views

Optimized linear to sRGB GLSL

I'm currently using a simple implementation of linear to sRGB transform: float sRGB(float x) { if (x <= 0.00031308) return 12.92 * x; else return 1.055*pow(x,(1.0 / 2.4) ) ...
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 ...
2
votes
1answer
63 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 ...
0
votes
0answers
98 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
votes
0answers
47 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, ...
0
votes
1answer
102 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 ...
0
votes
2answers
121 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 ...
0
votes
3answers
1k views

Can't render to FBO using a shader

I've added functionality so that I can render to a framebuffer (for post-processing and stuff). I can successfully render to my framebuffer and then render that framebuffer, but anything with a ...
4
votes
1answer
253 views

GLSL 2D Silhouette

I'm trying to render a silhouette of any entity behind foreground objects to indicate their position to the player. Here's an example of what I want to achieve, from Hyper Light Drifter: From what ...
0
votes
0answers
50 views

ETC1 texture opacity

I'm using the cocos2d-x engine and want to support etc1 on android devices for my game. For ETC1 i'm using the mali compression tool, and GLSL. Everything is working, but I can't change the opacity ...
0
votes
0answers
42 views

GLSL lighting shader with model scale

Basically, i'm just trying to find out where to insert the model scale into the lighting calculations. Ive searched the web, but amazingly, couldn't find anything dealing with scale + GLSL. This is ...
0
votes
2answers
243 views

GLSL Fragment shader lighting lambert term

Just a simple question: Should I or should i not normalize the SurfaceToLight vector to calculate the lambert term on a GLSL lighting shader? I mean, here: vec3 CalculateLights ( void ) { vec3 ...
1
vote
1answer
256 views

ETC1 Support on android alpha problem (GLSL cocos2d-x)

I want to support etc1 in my game, but somehow it doesn't work (I'm using cocos2d-x C++ GLProgram* glp = new GLProgram(); glp->initWithVertexShaderFilename("testv.vsh", "test.fsh"); ...
2
votes
1answer
201 views

GLSL 330 Core Bug? - Uniform variable will not set to value if it is named a certain way

In the code below I have a uniform variable named "vw_matrix" used in the calculation for gl_Position. When I run my program, a rectangle gets printed to the screen. #version 330 core layout ...
2
votes
0answers
175 views

Texturing Objects in OpenGL

Using OpenGL tutorials found here, I constructed an .obj file loader as well as a texture file loader using SOIL. I have an issue with drawing a textured object. (Shown here) Assuming I created the ...