A programming language for OpenGL shaders.

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84 views

Uniform Buffer Binding-points

I believe Uniform Buffers/Blocks has been the hardest thing to grasp in OpenGL. Hopefully this will be my final issue regarding this. I have created a uniform buffer that contain data of Light ...
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1answer
62 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 ...
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74 views

Assimp - generate tangents and bitangents

I have started using Assmip 3.1.1 in my OpenGL application. Let's consider a simple example. Here is obj triangle model: mtllib triangle.mtl v -5.0 0.0 0.0 v 0.0 0.0 0.0 v 0.0 5.0 0.0 vn 0.0 0.0 ...
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1answer
82 views

Render model with meshes with materials and/or textures

I'm making a model class that is using Assimp in the background. I want my models' meshes to be able to have a material and an optional texture on top of that. Right now I'm doing it like this: for ...
7
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1answer
658 views

How to implement this kind of ripples with a GLSL fragment shader?

So I have already implemented the reflection part: uniform sampler2D texture; uniform vec2 resolution; uniform vec3 overlayColor; void main() { vec2 uv = gl_FragCoord.xy / resolution.xy; if (uv.y ...
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1answer
68 views

Cubemap faces rotation in GS shader

I Can't get correct rotations for cubemap faces. Thats should come to geometry shader, from camera "view" matrix I want make 6 faces for my cubemap, but seems I can't get it correctly... My first ...
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1answer
138 views

Trying to implement Camera

I'm trying to implement a Camera class in order to walk and look on the world as follow: #ifndef _CAMERA_H_ #define _CAMERA_H_ #include <glm\glm.hpp> class Camera { public: Camera(); ...
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1answer
110 views

How to calculate reflection vector from point sprite sphere?

So far I achieved building a cube map following this tutorial. Then I drew three points using glDrawArrays(GL_POINTS,0,3) and calculate the normals based on a sphere. To compute the incoming light ...
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1answer
118 views

Fragment Shader output type error

StackExchange! I've been working with opengl for a bit and I'm trying to finally load the shaders instead of having them inline. I'm having a ton of issues, though. As soon as I solve one, another ...
2
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1answer
61 views

Failing to move exponential depth term to depth shader in exponential shadow mapping

I'm playing around in my little toy project to see if I can understand how exponential shadow mapping works. To begin, I have the following two fragment shaders: Light depth texture shader ...
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1answer
71 views

how to turn (or solidify) water or fuild into solid material (Renderring Effect)

i want to implement an effect like this. for example, let's assume the clay are made of particles. liquids of clay flows for a while, then it becomes dry and rest.finally those particles becomes only ...
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1answer
431 views

C++ OpenGL ShadowMap Issue/Artifacts

I am currently implementing basic shadow mapping in my C++ Custom Engine using GLSL 4.10. It is currently working with basic PCF anti-aliasing and very minimal reduction for unwanted artifacts. Here ...
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1answer
75 views

Reconstruct shader vertices in OpenGL

I'm not sure if 'reconstruct' is the correct term for this but essentially what I am trying to do is calculate vertex positions (that are already calculated via shader) on the CPU for the purpose of ...
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1answer
134 views

How to optimize my lighting shader?

I want to create a lighting effect on a gray-scaled world using cocos2d-x. What I've done is creating a layer which runs a shader program that receives light positions and radiuses as input and ...
0
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2answers
55 views

Overload how an object instance of a class is treated when used

So I've made this struct that encapsulates a glm::vec4. This is because vec3s are treated as 16-byte in GLSL, but I don't want to assign a vec4 if I only really need 3 components. Anyway, my question ...
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1answer
84 views

Ray casting problem using JOGL

I'm trying to port an old perfectly functioning ray casting implementation from my lwjgl project (FF pipeline) to a new project using JOGL and shaders. My problem is that my ray no longer intersects ...
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0answers
91 views

Artifacts rendering high-poly procedural meshes with OpenGL

I am having some issues when rendering some procedural generated meshes. There are some really wierd artifacts when rendering high-poly count meshes (not that much actualy). I have been able to ...
3
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1answer
385 views

I want to render some surfaces in GLSL with normal maps, and some without

I have normal mapping working in my game, but I want to only use normal mapping for some surfaces, and not others. Right now, as far as I can tell, my shader is applying an incorrect normal of (0, 0, ...
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0answers
80 views

Dynamic VBO update possibly corrupting data?

I want to draw a line between two vertices. On a mouseclick the vertex data will change and I want to update the line to use the new values. I am using a VBO for this and it looks like the update ...
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1answer
106 views

How do I convert from rectangular to spherical coordinates?

This seems like a fairly basic and common problem. Is there a builtin way to achieve it or do I have to write the algorithm on my own? If I do, how should it work?
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3answers
208 views

Combine flat and smooth shading with a single model geometry

I need to be able to switch between smooth and flat shading interactively. Is there a way to do this efficiently with a single geometry? For example, smooth shading does not require duplicate ...
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0answers
83 views

Tessellation shader pass-through : Nothing displayed

I am trying to set a pass-through tessellation shader and then build on top of that while learning. From what I found/read I need to do in the TE shader everything that was done in the vertex shader ...
1
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1answer
63 views

Is it possible to look up a texel from a texture in GLES2 GLSL framgent shader without using sampler?

Is there some way I can directly access texture memory from fragment shader in GLES2 GLSL? I don't need the sampler to be involved since I am just using it as a look-up table.
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1answer
117 views

Is it possible to use unnormalized texture coordinates from a GLES2 GLSL fragment shader?

I want to look up a texel from my GLES2 GLSL fragment shader using un-normalized texture coordinates (0-w, 0-h instead of 0-1, 0-1). The reason is that this texture is used as a look up table and I ...
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1answer
105 views

Uniform Block solve padding/alignment for vec3 in CPU struct

I have a struct on the CPU which I'm sending to a uniform block in my shader. After a bit frustration I finally got it to work. The problem I had was that vec3s are actually treated as 16-bytes, or in ...
1
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1answer
50 views

What is the fastest way to know if the current coordinate in screen-space is odd or even in GLSL/GLES2 frag shader?

I want to make a post-effect where every second column of pixels is colored differently, and I want to implement this as a GLSL fragment shader on GLES2. The question is what is the most effective way ...
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1answer
166 views

Basic terrain shader without using external texture

I have this: (Right now I have the height map in a x*x size 2D array and a 1D vector too.) What I am trying to achieve is something like this: Without using any textures, only plain colors. So ...
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0answers
24 views

Artefact in VSM as if GL_DEPTH_TEST disabled

I am trying to implement VSM and I incurred in a strange issue. I render them as follow: glUseProgram(shadowMapProgramID); glEnableVertexAttribArray(0); glBindFramebuffer(GL_FRAMEBUFFER, ...
0
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0answers
24 views

Transform screenquad around object's view space boundaries (GLSL)

Im not sure how to ask this, but essentially I am looking for a way to optimize rendering screen quad lights per object. I have a deferred renderer that draws directional lights onto a screen quad. ...
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2answers
217 views

How can I pass a std::vector<Vector3f> to my shader?

I have a Vector3f type which has x, y, and z properties. I have a std::vector of these vertices which describe my terrain. I would like to pass these values to a vertex shader through a uniform ...
2
votes
1answer
131 views

Shader - Transmittance or Absorption

I am trying to create a transmittance or absorption shader (glsl, hlsl, cg, etc...) in realtime but I don't find any good tutorial or white paper about this subject. I only find offline rendering ...
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1answer
130 views

Is it possible to calculate the TBN matrix in the fragment shader?

Just from model position, model normal and texture uv?
0
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1answer
162 views

How to load and render PhysX 3.3 heightfield

I'm trying to load a PhysX 3.3 heightmap and render it with OpenGL using glm and glfw, but so far it doesn't seem to be working. I'm basing my code on the PhysX samples, and am also using FreeImage to ...
0
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1answer
101 views

Per vertex diffuse lighting not propogating across entire model

I'm not sure how to describe this problem so I've added a picture. When I add per vertex diffuse lighting to my model (just a field of cubes for simplicity) the lighting effect applies to each ...
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1answer
569 views

What is the relationship between glVertexAttribPointer index and GLSL location?

I've been getting some strange results when trying to implement a normals buffer for the purpose of rendering lighting. It seems to be related to the indexes for glEnableVertexAttribArray, ...
2
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1answer
147 views

How to share values between different shader programs?

I am using Unity but this might concerns all type of shaders. I would like to know if this is possible to share values between different shader pass.Let's imagine that I am computing something in the ...
3
votes
2answers
183 views

Shader - Calculate depth relative to Object

I am trying to calculate depth relative to the object.Here is a good solution to retrieve depth relative to camera : Depth as distance to camera plane in GLSL varying float distToCamera; void main() ...
0
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1answer
121 views

GLSL: Vertex attribute to int

I'm trying to write a shader which renders a multitextured geometry wihout rerendering the geometry with each texture. In my test I'm not using textures, I just convert the texture index to a color ...
1
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1answer
216 views

Problem with uniforms in OpenGL

I have a strange problem I can't figure out. On the CPU I have class that handles the material properties for a model. material = new Material(); material->Emissive = vec3(0.1, 0.0, 0.0); ...
0
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3answers
79 views

Arbitrary number of VBO to Vertex Shader

I am currently using standard modern OpenGL way to render a mesh via VBO and attributes glEnableVertexAttribArray(aVertexPosition); glBindBuffer(GL_ARRAY_BUFFER, VBO); ...
0
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1answer
139 views

Why does my vertex shader produce no output until I add some arbitrary value to the position attribute?

I want to draw a textured quad but there is nothing drawn and the setup should be right. This is my vertex shader: #version 330 in vec2 position; in vec2 texel; out vec2 texCoord; void main() { ...
3
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1answer
293 views

Skybox rendering

I am sorry if this is trivial, but I got into OpenGL just very very recently. I am trying to render skybox (with cubemaps) and this is what I have done: Created a VBO with vertices positions (36 ...
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1answer
261 views

GLSL- How to change a certain color of a sprite, to another color passed into the shader?

There are sprites, with certain pixels being bright pink, and a shader dyes these pink or grayscale pixels to a custom color determined by the player. For example, a character looks normal except for ...
0
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0answers
154 views

Problems texturing a sphere using a cubemap

I have a single problem which I've attempted two methods to resolve. Neither is giving me 100% results. I've read about 100 tutorials and looked at code but it's just not working out for me; I believe ...
2
votes
1answer
179 views

OpenTK GL.DrawElements is never called

I found this C++ code here. It draws simple rectangle. Works great. #define GLEW_STATIC #include <iostream> #include <glew.h> #include <freeglut.h> const GLchar* vertexSource = ...
0
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0answers
92 views

Is it possible to loop over an array of samplerCube/samplerCubeShadow using OpenGL/GLSL?

I try to manage a scene with several point lights. For the moment my program works perfectly with just one point light. So I have in my fragment shader the following uniform declaration: uniform ...
6
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1answer
224 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 ...
0
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1answer
225 views

3D position of an arbitrary UV coordinate

I have a UV map for a 3D mesh that encodes "links" between pairs of UV coordinates. I have previously defined this links (or pairs), one to one. The links are enconded using the function rgb_color(u1, ...
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2answers
116 views

Vertex Skinning Looks Messy on Real Android Device using Monodroid

I have no problem doing the "vertex skinning" for three-dimensional animation. All goes well when using the emulator (and genymotion). However, when run on a real device (such as Samsung and Lenovo) ...
2
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1answer
60 views

How to know when graphics driver or card changes

I'm about to start work on implementing GLSL binary shader compilation and I was curious how to handle the cases when the shaders need to be recompiled, such as when the driver (or perhaps even the ...