a computer program that runs on graphics hardware and provides a high degree of control over how scenes are rendered

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233 views

What is the maximum number of shaders I can have in OpenGL 4?

What is the maximum limit of shaders I can have on the GPU? With 1000 different objects, I might have 1000 * 5 shaders (vertex, tcs, tes, geo, frag) on the GPU at a time. Though only one will be ...
3
votes
1answer
775 views

Multiple Textures in Shader?

I have this (pseudo) code: unsigned int TextureLoc = glGetUniformLocation(programID, "objectTexture"); for(int i = 0; i < object->texturesCount; i++) { glActivateTexture(GL_TEXTURE0); ...
3
votes
1answer
486 views

Rendering different materials in a voxel terrain

Each voxel datapoint in my terrain model is made up of two properties: density and material type. Each is stored as an unsigned integer value (but the density is interpreted as a decimal value ...
3
votes
2answers
1k views

Learning OpenGL GLSL - VAO buffer problems?

I've just started digging through OpenGL and GLSL, and now stumbled on something I can't get my head around this one!? I've stepped back to loading a simple cube and using a simple shader on it, but ...
3
votes
1answer
213 views

How can I determine the extreme color values in a texture?

I am looking for a way to determine the most extreme color values for all of the texels in a texture. So for a texture consisting only of black and white texels, the extreme values should be (0,0,0) ...
3
votes
1answer
858 views

Issue with interpolation on a burn shader (lerp and smoothstep)

I'm trying to create a simple burn shader. See here for more info on the method I'm using. However, I don't get why replacing the smoothstep with a lerp results in completely different results. Am I ...
3
votes
1answer
478 views

Matrix in constant buffer on the GPU contains NaNs but not on the CPU

I've got a shader with the following constant buffer: cbuffer ShaderParameters { matrix inverseViewProjectionMatrix; float4 cameraPosition; }; When using Visual Studio 2012's graphic ...
3
votes
1answer
3k views

GLSL if-else statement unexpected behaviour

This question is related to this other one I asked a few days ago. Because I have finally get to the bottom of the issue, I have rather preferred to open a new question with a more detailed ...
3
votes
2answers
907 views

implementing multi pass rendering in a game engine

I have done multi pass rendering before and understand how it works. I did a simple example which rendered a basic scene with shadows. This was all done in one file. Now I am trying to figure out is ...
3
votes
2answers
7k views

Can't update DirectX11 shader constant buffer [closed]

Alright, I'm currently making the transition from DirectX 10 to DirectX 11 (with very little help from the MSDN documention) and recently ran into a snag with updating a shader's constant buffer. My ...
3
votes
2answers
77 views

Local shape color blending

I am trying to implement this in Unity 4 Pro. But I am stuck in the blending part. I don't understand how you could blend multiples textures/colors using multiples volumes on an object. How could you ...
3
votes
1answer
311 views

Using a switch command in one shader vs multiple shaders

If you have multiple shaders, could you instead of switching between shaders all the time just have one shader with a switch and each case will send you along to another shader function which you ...
3
votes
1answer
120 views

Do I need Texture Units when NOT using shaders?

Does calling glActiveTexture() even make sense when not using shaders? I only have to switch the textures before drawing a buffer with glBindTexture(), right?
3
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2answers
197 views

Shaders and Performance

I'm coding my first Shader in my little game engine, and I have some questions about it's performance and common approaches. Is the Shader code processed by the video card instead of the PC ...
3
votes
1answer
745 views

Is the series of books “GPU Gems” still good for a modern OpenGL 3.0+ approach?

I noticed that this series of free books from Nvidia is really popular and well know in the devs world, the problem is that is simply old; you would recommend to read those 3 books to a developer that ...
3
votes
1answer
428 views

Complex shading using one single (small) texture

Recently I stumbled upon a demo reel in UDK about how one can attain beautiful results using just one (rather tiny) texture that's being sent to the shader pipeline. The famous link is this one. ...
3
votes
1answer
4k views

Simple GLSL example to render a 2d textured quad?

I would really love to add shader support in my game , although i can't seem to find a SIMPLE example on how to setup opengl for using shaders. So i would like to ask : Does anyone knows if there are ...
3
votes
2answers
63 views

How can I draw curves above a mesh surface?

I am making an animation of a deformed sphere that represents some aspects of the wave function in a hydrogen atom. I am starting with an octahedron that i push through a tessellation shader. The ...
3
votes
2answers
172 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() ...
3
votes
1answer
108 views

Desaturate texture using mask in OpenGL 2

I have a very large texture i am using as background and i want to apply a filter to a small part of it, the "small part" is defined by the alpha layer of another texture i have (which is still ...
3
votes
1answer
79 views

Why does my PixelShader ignore color but respond to alpha changes?

I started teaching myself some DirectX a short time ago and found something I'm confused about. For some reason, I can only get the color of the model I'm drawing to vary between black and white, ...
3
votes
1answer
200 views

When are HLSL literals taken as a float and integer?

float2 uv = float2(fX % 1, fY % 1) * 1/16; In the above example 1/16 is treated as a float, multiplying the float2 by 0.0625, but in: float2 uv = float2(fX % 1, fY % 1) * 1/16 + float2(1/16,0); ...
3
votes
2answers
162 views

Opengl shader questions

I'm currently building a shader that takes a 2D texture sampler and uses UV coordinates to map it. This works fine for all textured objects. However, I'm having a bit of a problem as I'm trying to ...
3
votes
1answer
2k views

How to draw a Bezier line with shaders?

I found a shader code to draw filled Quadratic Bezier in http://http.developer.nvidia.com/GPUGems3/gpugems3_ch25.html How can use something similar to draw a Bezier line that follows the same path? ...
3
votes
1answer
547 views

How do I render a filled and stroked path using OpenGL?

I want to render a 2-dimensional geometric path consisting of Bézier curves and straight lines. Paths can be concave. What is the most efficient way to draw this using modern OpenGL? Can I do this ...
3
votes
1answer
192 views

Why are some objects not rendering properly?

Here's a button I exported from Blender into a .x format: Now here it is in the game with BasicEffect applied to everything: And now with my custom shader: And there's the problem. While the ...
3
votes
1answer
378 views

How do I make a more or less realistic water surface?

I want to make a similar water surface like in this picture: I need the water surface in the same view than in the picture. Is it possible to work without shaders? I want to develop a little game ...
3
votes
2answers
281 views

Which will be faster? Switching shaders or ignore that some cases don't need full code?

I have two types of 2d objects: In first case (for about 70% of objects), I need that code in the shader: float2 texCoord = input.TexCoord + textureCoord.xy But in the second case I have to use: ...
3
votes
1answer
689 views

Spherical fractal noise generator in shader

I have a growing sphere in space, and I thought of having a procedural generated texture over it. Since it is growing, I thought a fractal would be a great choice, because more details would be ...
3
votes
2answers
206 views

Possible to create transparency shader which doesn't stack alpha values

The image above best demonstrates what I'm trying to achieve. It's a transparent shader for objects, but wherever the objects with this shader intersect they don't add together but simply merge with ...
3
votes
1answer
249 views

Multiple pixel shader passes

I currently have a pixel shader that calculates the texture and I have another that calculates the light. I want another shader that does both. What I would ideally like to do is instead of creating a ...
3
votes
2answers
119 views

Are buffers in OpenGL associated with GLSL programs?

I have two different shader programs in my OpenGL code. 1- renders simple font using freetype 2- simple shader which draw primitive shapes. I sent both of them some data using buffers, I understood ...
3
votes
1answer
326 views

Odd blending result (semi-transparent 2d quad over 3D scene)

I'm working on a GUI library for my game, and I'm having problems with my blending. I have a 3D scene, which I render with glDrawArrays. In the fragment shader the alpha color is hardcoded 1.0f ...
3
votes
1answer
179 views

Messed up UVs in Unity3D for Android

All of my quads appear correctly textured on the Unity3D editor, a Motorola Xoom Android tablet, and on an iPad 2: But on our Samsung Galaxy Mini 2 smartphone they kinda look like this: I wrote ...
3
votes
1answer
2k views

How are vertex shader outs sent as inputs to the fragment shader?

I'm learning some OpenGL 3.2 way of doing things and I think it's quite great, I'm actually understanding more of shaders and non-fixed pipeline in 1 week rather than those 2 years I tried to learn ...
3
votes
1answer
320 views

cocos2d mask rotation

I've been experimenting with Ray Wenderlich's tutorial about masking sprite using shaders with cocos2D 2.0. It works pretty well but now I'd like to rotate the mask independently of the masked ...
3
votes
1answer
762 views

Monogame/SharpDX - Shader parameters missing

I am currently working on a simple game that I am building in Windows 8 using MonoGame (develop3d). I am using some shader code from a tutorial (made by Charles Humphrey) and having an issue ...
3
votes
1answer
694 views

Shadow-mapping xna

I've been trying to implement shadows in my game and I've been following quite a few tutorials online, mainly Riemers, but I'm always getting the same 2 errors when I'm drawing my models and setting ...
3
votes
2answers
575 views

WebGL geometry calculations

I have a dynamic surface in WebGL, that is animated in vertex shader. I want other objects to interact with this surface (for example, an object riding on dynamic terrain). What's the best way to do ...
3
votes
1answer
850 views

How'd they do it: TF2 payload cart glow?

How did the creators of TF2 make the glow on the payload cart visible through walls? Is it possible to implement this in Unity's shaderlab?
3
votes
1answer
1k views

OpenGL ES Basic Fragment Shader help with transparency

I have just spent my first half hour playing with the shader language. I have modified the basic program I have which renders the texture, to allow me to colour the texture. varying vec2 texCoord; ...
3
votes
2answers
1k views

Unity - Part of the sprite is covered in shadow

I have a sprite with Transparent/Cutout/Diffuse shader. Recieving shadows is turned on in SpriteRenderer. The light is a pointlight and I am using deffered rendering path. However when I am above or ...
3
votes
1answer
126 views

Using normals in DirectX 10

I've got a working OBJ loader that loads vertices, indices, texture coordinates, and normals. As of right now it doesn't process texture coordinates or normals but it stores them in arrays and creates ...
3
votes
1answer
278 views

Is multipass rendering possible with SpriteBatch?

I'm trying to implement a bloom effect. This requires three shader passes: a brightness threshold, a horizontal blur, and a vertical blur. It also requires resizes, but these are irrelevant to the ...
3
votes
1answer
721 views

How do I create a manual object with colors for each vertex?

How do I create a shaded manual object with colours for each vertex? Eg if ogreObj is the Ogre::ManualObject : ogreObj->begin("BaseWhiteNoLighting", Ogre::RenderOperation::OT_TRIANGLE_LIST); ...
3
votes
1answer
142 views

How to categorize textures into atlases

I am going to use texture atlasing for the first time in my games, and at first it seemed like a great idea to split textures into atlases by categorizing them by terrain themes e.g ForestTextures, ...
3
votes
1answer
297 views

Directional light shader not behaving as expected

I coded my first glsl shader which manage diffuse and specular effects of a directional light. This is the fragment shader. #version 120 //matrix uniform mat4 model_matrix; //directional light ...
3
votes
1answer
118 views

Surface normal to screen angle

I've been struggling to get this working. I simply wish to take a surface normal and convert it to a screen angle. As an example, assuming we're working with the highlighted surface on the sphere ...
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 ...
3
votes
2answers
732 views

Techniques for reducing terrain shader complexity

My terrain shader does quite a bit, but I don't know how to break it up in any way that will reduce my instruction count without removing key features of the terrain. It does the following: ...