A programming language for OpenGL shaders.

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3
votes
2answers
303 views

Using a programmable pipeline in a game engine

As a learning experience, I'm developing my own 3D game engine using OpenGL. I'm a little confused as to how to implement my rendering engine such that it uses a programmable pipeline while still ...
0
votes
1answer
1k views

How to draw a circle with WebGL using GL_POINTS [closed]

I'm trying to draw a circle using simple vertices points and a big gl_PointSize value. I found this example and try to reproduce it on WebGL with no success.
7
votes
1answer
1k views

Optimizing performance of a heavy fragment shader

I need help optimizing the following set of shaders: Vertex: precision mediump float; uniform vec2 rubyTextureSize; attribute vec4 vPosition; attribute vec2 a_TexCoordinate; varying vec2 tc; ...
-1
votes
1answer
117 views

Shader applied to Texture is not showed in GLSLES

I'm trying to learn the basic of shaders following basic tutorials in Ogre. I use GLSL ES 2.0 #version 100 I think I have a basic concept problem. I'm trying to render a model + texture without make ...
0
votes
0answers
298 views

Specular Light not working Phong shading

I want to implement Phong-Shading using GLSL. I also want to calulate all values using uniforms in the shaders. Nearly everything works fine, but there is an error with the specular term of the ...
0
votes
1answer
96 views

Direction from the camera to the light source

I'm currently writing a game using OpenGL and GLSL. For the shader I need the direction from the current camera to the light source. The lightsource is given by lightSource.position as a uniform as ...
1
vote
3answers
1k views

Set a variable inside a GLSL fragment shader that persists for the render

Is it possible to set a varying variable inside a fragment shader and have it persist? I'd like to use the depth component of the first fragment and use it on all the others, making the fragments all ...
3
votes
2answers
3k views

2D water shader similar to Limbo's effect

I'm wondering how I would go about creating a 2D water shader that is seen in this video http://www.youtube.com/watch?v=phChFfi4GOs The water effect that limbo uses is pretty awesome. I'm not so ...
0
votes
1answer
215 views

bump mapping with 2 normal maps

I was wondering if its actually possible to do bump mapping with 2 normal maps... I have tried doing it this way however I get a function overload on max and dot. uniform sampler2D n_mapTex; uniform ...
0
votes
1answer
138 views

texture movement stutters

Hey I at the moment I have got my texture to move however it stutters as I increment by 0.001 every second. My animation is done via FPS if that make sense and here is some code FrameCount++; ...
0
votes
1answer
253 views

texture won't move OpenGL ES 2.0

I want be able to move my texture in GLSL I have set my texture to wrap S and wrap T but not sure why it wont move my fragment shader looks like this at the moment uniform sampler2D n_mapTex; ...
3
votes
2answers
1k views

scaling point sprites with distance

How can you scale a point sprite by its distance from the camera? GLSL fragment shader: gl_PointSize = size / gl_Position.w; seems along the right tracks; for any given scene all sprites seem nicely ...
4
votes
1answer
976 views

variable number of lights in a glsl shader?

I want to render an arbitrary number of lights in my fragment shader. I do not understand how you can properly pass them into the shader though. For example, I want something like this: uniform int ...
0
votes
1answer
126 views

How to alter the angle of texture projection

I'm currently working on a 3Dish game; it's on a grid, with 3D props and the camera looking down on the grid at about 45º, but I want to use 2D sprites for the player and NPCs. Currently, I'm using a ...
-1
votes
2answers
256 views

GLSL: Why can only some of the matrices be found? [closed]

I've been learning GLSL and to start I've been trying to replicate the fixed-function pipeline functionality with it, for 2D graphics. I've done it successfully in most things, so far, but I came into ...
2
votes
1answer
224 views

gbuffer - how to store an integer data

In a gbuffer I store a diffuse color in following texture: glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); I want to store an integer data which ...
5
votes
1answer
2k views

How to do simple bump mapping

I'm trying to do bump mapping, and I'm getting fairly close at achieving my goal. I miss one crucial piece of my puzzle to have bump mapped effect in my scene; I need to transform the normals from my ...
0
votes
1answer
1k views

Reinhard tone mapping and color space [closed]

I found two ways of doing tone mapping (first, second): //Ld - this part of the code is the same for both versions float lum = dot(rgb, vec3(0.2126f, 0.7152f, 0.0722f)); float L = (scale / ...
2
votes
1answer
409 views

RGB to xyY color space conversion and luminance

The luminance calculated by following GLSL functions (fragment shaders - tonemap) has different value: float GetLuminance (vec3 rgb) { return (0.2126 * rgb.x) + (0.7152 * rgb.y) + (0.0722 * ...
2
votes
0answers
229 views

iPhone GLSL shader dynamic branching issue

I am trying to pass an array of vec3 as uniform and then iterate through them on each pixel. The size of array varies on situations so I can't make the loop with constant number of iterations. ...
0
votes
1answer
198 views

How do I pass textures into a fragment shader in Slick?

I've written a shader that uses three different textures, tex0, tex1, and tex2. I can load it into Slick and successfully display it, but I can't figure out how to set the three different textures. ...
2
votes
2answers
2k views

GLSL Motion blur on mobile.. possible at acceptable framerates?

I have been struggling to implement a simple linear motion blur effect on mobile (Android, OpenGLES 2.0) but it just seems to destroy my framerate. I'm rendering to texture (FBO) then applying a ...
2
votes
1answer
453 views

How to solve artifacts caused by vertex lighting in my voxel engine?

My current lighting system bakes the light amount based on ray-tracing from the light source to the 8 corners of the block (so per-vertex) and the distance to the light on the blocks. It works ...
0
votes
1answer
302 views

How to get a smooth dimming with SSAO?

I implemented SSAO in my game based on the tutorial at gamerendering.com. But the results I get are disappointing. Instead of a smooth effect as seen in the nvidia demos, my implementation causes ...
0
votes
2answers
264 views

LWJGL Game crashes on some other machines [closed]

I just tried running my game on a friend's laptop, but for some reason it crashes. The exported .jar runs fine on my machine, and some others too. I can see that is has something to do with the ...
4
votes
3answers
753 views

Voxel engine artifacts

There are white little dots between blocks at random places, mainly at very near blocks. They disappear when I move the mouse and change the view direction. I use Vertex Arrays with ...
1
vote
1answer
191 views

OpenGL VBO Additional Attributes

If I have a buffer with my vertices, normals and texture coordinates, and I use glDrawArrays to draw the VBO to the screen, how can I send attributes per vertex that I placed in an array to the shader ...
4
votes
2answers
739 views

Do opengl games tend to use multiple shaders? [duplicate]

For any given object that you want to render, there may be a whole bunch of things that need to be considered for rendering (Material, Texture, Lighting, Blending etc). But, you may also have some ...
2
votes
1answer
1k views

glsl 150 struct in uniform buffer object

Can I do this in opengl 3.2 / glsl 150? glsl shader: struct LightSource { vec4 ambient; vec4 diffuse; vec4 specular; vec4 position; vec4 direction; }; ... layout(std140) uniform ...
2
votes
1answer
260 views

How to transform a shadow map to camera view?

I'm making a rendering engine as a hobby to learn more about 3D. I have a deferred renderer with the G-buffer (color, normal and depth). I also have a lighting controller that uses only spotlights at ...
-5
votes
3answers
362 views

in the shadow of a sphere [duplicate]

(Related, but somewhat different, to my previous question) How can I determine in a fragment shader if a fragment is in the shadow of a sphere? That is, if it is occluded by the sphere and is past ...
5
votes
1answer
1k views

What is the recommended way to output values to FBO targets? (OpenGL 3.3 + GLSL 330)

I'll begin by apologizing for any dumb assumptions you might find in the code below since I'm still pretty much green when it comes to OpenGL programming. I'm currently trying to implement deferred ...
0
votes
1answer
2k views

Simple pass-through geometry shader with normal and color

I've written a very simple pass-through geometry shader. My input and output primitives are points. I also want to forward the color and normal from vertex shader to fragment shader through geometry ...
1
vote
1answer
288 views

Using two FBOs results in the second FBO having nothing drawn to [closed]

I'm writing a deferred renderer, and I use two FBOs: the first one for G-buffer (color, normal, depth) and the second one for lighting (light output), so the first one has three textures bound and the ...
4
votes
2answers
717 views

Jagged transparency when rendering translucent textures (OpenGL 3.2 + GLSL)

Like most others, I'll start off mentioning that I'm still a beginner when it comes to OpenGL and GLSL programming. So bear with me on any dumb mistakes you may spot in the code ahead. I'm basically ...
-1
votes
1answer
472 views

GLSL code is very slow…why? [closed]

I know this is a very difficult thing to simply modify without the full project code, but I am having a massive performance problem with GLSL code that seems to be very efficient to me. I am stuck at ...
1
vote
1answer
270 views

My game works on the emulator and the PSVita, but crashes on Android

I made a game on PSM, ported from a previous iOS/Android game. I test it on the emulator and PSVita and runs fine. However, as I test it on a PlayStation Certified Android device, it crashes on load. ...
3
votes
1answer
961 views

Cook Torrance model implementation : black specular light

I am trying to implement the Cook-Torrance model, and this is how I calculate the parameter Rs: float Rs(float m,float F,vec3 N, vec3 L,vec3 V, vec3 H) { float result; float NdotV= ...
1
vote
1answer
579 views

How to rotate a direction

I'm working a spotlight for my deferred renderer and I'm having trouble with matching the mesh to the visual representation of the light. Right now my mesh is a cone, the apex of the cone is at ...
2
votes
1answer
142 views

Fragments never falling into spot light's cone

I am using GLSL version 1.20 with OpenGL 2.1 . I am trying to compute when a fragment falls into the area of a spot light. I have already set all the light values with glLightfv and glLightf, also ...
2
votes
1answer
573 views

Gaussian blur filter and “shimmering”

I have a fairly bog-standard Gaussian blur filter (seperable) I'm using to make a glow effect in my pipeline. At the moment I'm rendering it only to 256x256 texture and then doing a very simple ...
0
votes
3answers
352 views

Phong lighting model unrealistic result

I am using OpenGL 2.1 and GLSL 1.20 . I am trying to compute the fragment color applying the Phong lighting model. This is the formula I have (the original formula has a summation, but since the ...
1
vote
1answer
355 views

What book/guide should I follow for GLSL [closed]

I searched a lot on the web without coming to a real solution and if I ask this it's because I really have difficulties getting an answer. I need to learn well GLSL 1.20 with OpenGL 2.1. I have ...
0
votes
1answer
406 views

vec4 for vec3 multiplication while calculating the specular value

I'm following this tutorial to calculate the specular color of a vertex. I use OpenGL 2.1 with GLSL version 120. This is the formula that I apply: spec= (R*eye)^s * Ls * Lm With: ...
0
votes
1answer
142 views

deferred rendering and a few shading functions

How to use a few shading functions together with deferred rendering (for example some objects are shaded based on a lighting equation, other get a fixed color) ? I draw a full screen quad when ...
16
votes
1answer
2k views

Why does this geometry shader slow down my program so much?

I have an OpenGL program, and I'm rendering a terrain mesh. I displace the vertices in the vertex buffer and don't really color them in the fragment shader yet. I'm adding a geometry shader one part ...
2
votes
0answers
925 views

2D water shader in SFML

I want to implement the algorithm for a 2D water surface described here and here. Before somebody finds out, beats me up and deletes this, I'm gonna say it myself. I posted this question over at ...
2
votes
0answers
496 views

Shader Maker version 130 is not supported [closed]

I am trying to compile a vertex shader with Shader Maker and if I try to use the version 130 it says: Compiling Vertex Shader ERROR: 0:3: '' : version '130' is not supported Compiling ...
0
votes
1answer
186 views

OpenGL RTT FrameBuffer question and Rendering to texture while sampling it

What i need to do: Blur the selected texture and pass the texture to another effect for postprocessing. Notice that i want one texture passed all over. How do i want to do this: Bind the FBO ( ...
2
votes
1answer
254 views

Would I perform one pass per effect in Deferred Shading?

I'm implementing deferred shading the first time. Doing so I came up with a conceptual question. First I render the geometry in a framebuffer with muptiple rendering targets for depth, normals, and ...