A programming language for OpenGL shaders.

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14 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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0answers
20 views

Inconsistency with custom WebGL shaders under linux with Three.js [on hold]

I'm experiencing some weird behavior with a relatively small custom shaders. This is the expected behavior as seen under windows. Unfortunately under linux (you can see the files ...
0
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1answer
61 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
47 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
84 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
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2answers
147 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() ...
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0answers
50 views

GLSL array with variable index? [closed]

I have a GLSL fragment shader with this part of code: for(int i = 0; i < 10; i+=3){ vec3 l_pos = vec3(lightMat * vec4(light_poses[i],light_poses[i+1],light_poses[i+2],1)); vec3 ...
0
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1answer
44 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 ...
2
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0answers
99 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); ...
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3answers
66 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
57 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() { ...
2
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0answers
76 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
83 views

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

I have been googling for over an hour, trying to find out how to do something very simple, which I see in tons of games. I tried to understand GLSL, but it seems like a ton of learning for a single, ...
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0answers
54 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
80 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 = ...
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0answers
24 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 ...
4
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0answers
89 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
115 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
54 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
56 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 ...
0
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1answer
87 views

Blurring part of the screen - optimisation

I develop 3d menu and sometimes I need to blur only part of the screen. I use a forward rendering. I create a frame buffer object with 3 color attachments. Rendering looks like this: bind fbo ...
1
vote
1answer
32 views

Only affect pixels in buffer with alpha 0

I'm working on a transition effect where I have a texture and simply draw that as a pattern to my buffer. Here is a demo, use "e" to start the effect again. This looks fine but it won't work if the ...
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0answers
119 views

Is it reasonable to use a 2D texture as a lookup table in GLSL

I need a lookup table in a shader. The input values would be color values and the output other color values. Something like: uniform float lut[256]; color = vec3(lut[int(color.r*255.)], ...
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1answer
95 views

Vertex shader in OpenGL/GLSL - transformation of the interior of a textured quad

I have a LWJGL project and ran into a problem with a vertex shader I wrote. In my scene I am rendering a map whose ground consists of rectangular tiles. On top of that there are other objects (I used ...
0
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1answer
63 views

Proper way to encapsulate a Shader into different modules

I am planning to build a Shader system which can be accessed through different components/modules in C++. Each component has its own functionality like transform-relevated stuff (handle the MVP ...
0
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2answers
64 views

Best way to detect if vec3 is between vec3(x) and vec3(y) in glsl

As titled I am sampling from a texture and if the color is somehow gray [vec3(.8), vec3(.9)] and an uniform is 1 I need to substitute that color with another one I am not a glsl veteran but I am ...
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0answers
32 views

GLSL 150 (or upper) per pixel lighting base code

I'm looking for a working example of smooth per pixel shading for one directional light I've seen this example http://www.opengl.org/sdk/docs/tutorials/ClockworkCoders/lighting.php but its old GLSL ...
5
votes
1answer
238 views

How can glass breaking effect from Smash Hit be achieved? [duplicate]

I saw Smash Hit the other day and was amazed by the physics of the game, specially the shattered glass effect: I've read other posts about this subject but I still feel that they don't share enough ...
2
votes
2answers
150 views

Water silhouette shader using GLSL

I have this problem to solve using Cocos2d-x 3.x: In my game there is water represented by rectangle texture, modified by the code on the go. I also have a character moving around, rotating etc. I ...
0
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0answers
20 views

Shader | Special Effect - Unit selection [duplicate]

I would like to know how the shaders used to show which unit is selected are made. Here is an image to illustrate. How the merge effect of the blue circles can be achieved ? I didn't found any ...
1
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1answer
51 views

Unity, shader, vertexID

I'm writing a shader and I just wanna ask if it's possible to get the ID of the vertex that is currently being manipulated. I read something about gl_vertexID, but I couldn't find out if that is ...
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0answers
109 views

implementing shadows into my 2D GLSL-based lighting system

I'm writing a lighting system in OPENGL using GLSL shaders, and I'm pretty happy with the light casting I have so far, but I'm totally stuck on casting shadows. Everything I've found online on this ...
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1answer
106 views

GLSL Processed Image to OpenGL

I've tried wording and rewording this question in various forms of search and can't seem to find an answer to it. If I'm wording it wrong and/or just not finding the right information, feel free to ...
3
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2answers
133 views

Render with multiple lights (one pass per light)

I have already a system that at the moment handle multiple lights just passing an array of light struct and loop through it. I had been told to switch to a multipass rendering approach. How should I ...
1
vote
2answers
133 views

GLSL to Cg: why is the effect different?

With reference to this question, where I was trying to make the shader compile, I am now trying to make an effect appear. The effect can be shown here, through a GLSL shader: But when I use the ...
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2answers
94 views

Passing variables down the pipeline glsl

I am sorry to post a question that may be easily tested, but I don't have an OGL4+ hardware at the moment and I have to make some design decision beforehand so I wanted a clear scenario. Looking at ...
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1answer
78 views

GLSL to Cg fragment shader

I have found very useful resource on the Swiftless website on OpenGL. Unfortunately, I cannot manage to adapt a GLSL fragment shader to my project, which uses Cg. Here it is: uniform sampler2D ...
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0answers
127 views

Problem when using two different shaders

I have created a simple shader for drawing my scene in OpenGL. When another shader was introduced, a problem appeared. I use the first shader and draw few objects in the scene. Then I use the second ...
3
votes
1answer
123 views

what happens with missing vertices in geometry shader

I am relatively new to GLSL shader programming, and the documentation I found is unfortunately often inscrutable. I am having trouble understanding a few things with how geometry shaders fit into the ...
0
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1answer
75 views

What coordinates are we passing to pixel shader from vertex shader?

I have read articles about shader programing and understood the very basic knowledge of shader programing. One thing I always get confused is about the texture mapping. What I pass(output) from VS to ...
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0answers
96 views

How to shade hair (line segments) correctly in GLSL

I render my hair geometry in line segments. The problem I have is with the correct shading of the hair. From what I've read I understood that I need the direction of the line segment and the ...
0
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0answers
31 views

Shadow bias selection with moving light

I've been looking at shadow mapping and although I managed to get them to work selecting an appropriate bias. The problem is when I start moving the light. The shadows work fine for not extreme ...
0
votes
1answer
136 views

More than 8 lights without deferred shading / lighting [closed]

I want to know if there is any technique (efficient) to use more than 8 lights in a scene made ​​with OpenGL and GLSL. Without making use of deferred shading / lighting. I have not implementadon ...
1
vote
2answers
488 views

2D Outline shader in GLSL

I have a simple prototype with 2D worms-like destructible terrain. I use a trivial shader to discard pixels based on a mask. varying vec2 v_texCoords; uniform sampler2D u_texture; uniform sampler2D ...
1
vote
2answers
100 views

Bad pixels on shader when loading cached binary programs

I have been trying to cache binary shader programs in my game and load them accordingly using "glGetProgramBinaryOES" and "glProgramBinaryOES" respectively. I was successfully able to cache and load ...
2
votes
1answer
76 views

Handling multiple lights of different types in GLSL

I want to be able to support multiple lights of different types (point, spot & directional). Note that I also want to be able to render transparent/translucent objects, which rules out deferred ...
2
votes
3answers
339 views

GLSL Sphere from Vertex

I am working on a particle simulation where we have a lot of spheres which can have different radii. Using this tutorial http://mmmovania.blogspot.de/2011/01/point-sprites-as-spheres-in-opengl33.html ...
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0answers
52 views

gl_ClipDistance[] not working

I am unable to get gl_ClipDistance to work. The results I'm getting are the same as if I didn't enable clip distance. I have called glEnable(GL_CLIP_DISTANCE0); and glEnable(GL_CLIP_DISTANCE1); in ...
1
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1answer
83 views

Normal Mapping space confusion

I've been reading today about normal mapping. Up to now, the only normal mapping I encountered was with maps already in world space so I just extracted the info from the texture and transformed them ...
8
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1answer
163 views

How can I reliably implement GPU skinning in Android?

I'm trying to get character skinning working on Android. The idea is quite vanilla: I have my skinning matrices, and along with each vertex, I send up to four matrix indices and four corresponding ...