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

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3
votes
1answer
398 views

Spritebatch Vertex shader world matrix change after each draw

I have a spritebatch where I draw some textures transformed in 3d space. The easy way was just Begin with the transformation matrix, draw, and end it right after. But that is silly, so I'm trying ...
3
votes
0answers
440 views

Jet engine exhaust shader [closed]

How would I create a jet engine exhaust effect, as shown in the image from Fzero GX below. GLSL and OpenGL examples/solutions are prefered, though other resources are also welcome. Requirements ...
3
votes
1answer
227 views

Outlining external edges on a complex shape made of cubes?

A gallery of my problem can be found here. I had to do it this way as it won't let me post more than 2 links due to my reputation. I'm trying to use 3D cubes to generate an isometric cube world. I ...
3
votes
0answers
169 views

SSAO Distortion [closed]

I'm currently (attempting) to add SSAO to my engine, except it's...not really work, to say the least. I use a deferred renderer to render my scene. I have four render targets: Albedo, Light, Normal, ...
3
votes
0answers
800 views

Loading custom shader in Monogame [closed]

I have been trying to load this custom FX file into a Monogame project, and everything I try fails. (code taken from http://www.david-gouveia.com/scrolling-textures-with-zoom-and-rotation/) sampler ...
3
votes
0answers
934 views

Sampling from depth texture causes shader to stop working [closed]

I'm currently having issues with depth textures. When I sample from a depth texture it causes my other samplers to fail. For example, when I set gl_FragColor manually the depth buffer is correct. I ...
3
votes
2answers
450 views

Screen effects and antialiasing

I have been working on a game for a while using glut for basic window creation. I was rendering to an offscreen buffer so that I could implement various effects like screen bulging, motion blur, ...
2
votes
2answers
981 views

Optimizing gaussian blur with linear filtering

There's a few (here, and here) gaussian blur tutorials out there suggesting that you can essentially cut the number of texture lookups in a gaussian blur shader in half by exploiting the GPU's ...
2
votes
3answers
2k views

Why even use shaders?

assuming I want my game to have a Cel-shaded look. There are plenty of tutorials how to implement Cel-shading in hlsl f.e. But what is the point? If I am creating my assets with Blender or 3d-max I ...
2
votes
3answers
826 views

Rain effect using DirectX 9 capabilities

Is it possible to achieve something similar to nVidia's rain demo using only shader model 3.0 capabilities? If yes, could you point out a few documents/web resources that are suitable candidates and ...
2
votes
1answer
238 views

What are the factors that determine the default frequency of a shader call?

After i have been played for some days with various vertex and fragments shaders seems clear to me that this programs are called by the GPU at every and each rendering cycle, the problem is that I ...
2
votes
2answers
2k views

Updating texture memory via shader?

What the title says.Is it possible to update a texture via a glsl shader ? Something like : //Read vec4 Pixel = texture2D(TextureID,gl_TexCoord[TextureIndex].st); //Write to texture memory ? vec4 ...
2
votes
2answers
2k views

2d metaballs with shader to give blobs of water effect?

I want to simulate blobs of water in a 2d game in Unity3d. One possible way of doing it is to use 3d metaballs moving in a 2d plane though this is very processor intensive. Do you think it would be ...
2
votes
2answers
376 views

How can I remove branches from a fragment shader function?

I have a fragment shader, when I've carefully managed to remove most branching decisions, as I have found out through research here that they are bad. But I have one function that I just can't work ...
2
votes
2answers
168 views

Are global shader variables slower than texture look ups?

I want to send quite a bit of data to the GPU, the data will never change (or will change very rarely) after it has been created. Is there a performance impact to using global shader variables or ...
2
votes
1answer
713 views

How can I pass an array of floats to the fragment shader using textures?

I want to map out a 2D array of depth elements for the fragment shader to use to check depth against to create shadows. I want to be able to copy a float array into the GPU, but using large uniform ...
2
votes
2answers
557 views

Lighting problems with Terrain

I'm in the process of learning Open GL and am having issues with lighting on my Terrian, I don't know if the issue is related to how I calculate my normals or the shader itself (I am using the shader ...
2
votes
1answer
1k views

Shader optimization - Cg/HLSL pseudo and via multiplication

HLSL/Cg do not allow texture fetching inside conditional blocks. To get around this I am first checking a variable and performing some computations, afterwards I set a float flag to 0.0 or 1.0, ...
2
votes
3answers
3k views

2D shader to draw representation of rotating sphere

I want to display a 3D textured sphere, and then rotate it in one direction. The direction will never change, and the camera will never move. One way is to actually create a spherical mesh, map a ...
2
votes
1answer
126 views

How does the GPU know how to form triangles for a given mesh?

I have just begun learning shader programing. What I learned is that the rasteriser groups three vertices to form a triangle for doing further operations. If that's true how does the rasteriser ...
2
votes
2answers
1k views

Shader that “cuts” hole through all geometry

How can I create a shader that "cuts" through all geometry, only rendering the clearing background in Unity? An example: That's a prism in a huge white box-shaped room. The surface of the prism is ...
2
votes
1answer
247 views

GLSL Multiple Uniform Structs

I'm developing a lighting system for my voxel game, and I have to send multiple (alot, say up to 200) lights to my shader program. Those lights contain the following data: Position (vec3) Color ...
2
votes
2answers
176 views

State propagation in modern OpenGL

When last I dabbled in game development, I managed my geometry in a tree. Every node would call the render method on it's children, prior to resetting it's transformations, thus allowing the ...
2
votes
1answer
748 views

Low-level GPU code and Shader Compilation

Bear with me, because I will raise several questions at once. I still feel, though, that overall this can be treated as one question that may be answered succinctly. I recently dove into solidifying ...
2
votes
1answer
3k views

Unity custom shaders and z-fighting

I've just readed a chapter of Unity iOS Essential by Robert Wiebe. It shows a solution for handling z-figthing problem occuring while rendering a street on a plane with the same y offset. Basically ...
2
votes
1answer
237 views

Graphic hardware texture formats shaders relational speed

I'm interested to know, is there a direct correlation to the speed that a shader will run based on the bit depth of a texture upon which it is running. For example: If I have a 2 bit stencil texture ...
2
votes
1answer
238 views

Basic knowledge for 2d gaming and images?

Can anybody refer me some pdf or ebook that i should follow for basic 2d programming and texture ,shaders and other gaming elements details in depth.By which i can easily get through the 2d game ...
2
votes
2answers
1k views

Multiplatform GLSL shader validator?

Im working on a multiplatform (Pc,Mac,Linux) game that uses shaders quite extensively. Since we do not have any funding, it is pretty hard to test our game on all possible hardware configurations. ...
2
votes
1answer
1k views

How to make a custom semantics HLSL shader for the pixel shader

I'm pretty sure it's possible but i have no idea how. Could anyone tell me how to make a custom semantic for a pixel shader. Thanks
2
votes
1answer
103 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 ...
2
votes
2answers
486 views

How to implement Fog Of War with an shader?

Okay, I'm creating a RTS game and want to implement an AgeOfEmpires-like Fog Of War(FOW). That means a tile(or pixel) can be: 0% transparent (unexplored) 50% transparent black (explored but not in ...
2
votes
2answers
87 views

Palette reduction to pre-defined palette

I'm writing a bunch of GLSL effects for fun, but I can't wrap my head around this. Basically, I want to reduce a texture's palette into a pre-defined set of colors. For example, a post-processing ...
2
votes
1answer
121 views

How can I compile a Direct3D 9 effect from a file?

I started working with shaders recently in DirectX9. I noticed that there is a D3DXCompileShaderFromFile function for IDirect3DVertexShader9 and pixel shader. Which compiles the shader and gives you ...
2
votes
1answer
83 views

XNA 4.0 - Strange edges with multilight shader

I am generating a light, a depth and a normalmap to calculate the lightning at each pixel with multiple lights. On both rendertargets, i set the preferredMultiSampleCount parameter to 16 samples ...
2
votes
2answers
229 views

Does GLSL copy function arguments by value?

My question is about passing variables to GLSL shader. I'm not sure how that works and what are the performance implications. Say I got a function that accepts a "vec4" variable. The question is - is ...
2
votes
2answers
236 views

Where should shaders and lights be in a component-based entity system?

Where should I put the shader and the light / shadow calculation? Should that be a component too? And should the rendering system know how to handle them or should there be a separate light system? ...
2
votes
1answer
139 views

How do we apply different textures to different faces generated via geometry shader?

I am trying to render a cube by starting of with one vertex into the shader, then geometry shader to expand into a cube, and then apply a different texture to each side. The part I am facing the issue ...
2
votes
2answers
145 views

Replacing 4 additive sprite layers with a single shader. Just can't get it right

I'm using directx9 and have 4 textures I want to draw on top of each other. if I do this: PDevice->SetRenderState(D3DRS_SRCBLEND,D3DBLEND_SRCALPHA); ...
2
votes
1answer
196 views

Shader Variable Types

I have a simple question. what are the meaning of : half4 myHalf; myHalf.yyyy; myHalf.xxzz; // or myHalf.yw Thanks a lot !
2
votes
2answers
300 views

3D Distortion Effect

I'm trying to make a distortion effect similar to this: However I'm not making a 2d screen space effect. I'm applying it to a 3d scene and I want it to be placed IN the world, so it can be blocked ...
2
votes
1answer
106 views

What is a Fragment Pipe?

I remember someone saying "24 fragment pipes on nVidia 7800" in a presentation. Am I correct in saying that a fragment is the data that can generate a pixel in the frame buffer? Or are fragments the ...
2
votes
1answer
779 views

shader coding: calculate screen coordinates of fragment

Good morning, I'm new to shader coding and trying to implement some visual effects code in shaders using billboards. (Yes, I couldn't have picked anything harder to start with, but I'm lucky that way) ...
2
votes
2answers
2k views

OpenGL ES high-quality 2D scaling

Let's say I'm making a 2D game and I want to implement a zoom in/out feature. Normally this is as simple as modifying the projection matrix to get more or less of the world to show. However, this ...
2
votes
1answer
456 views

Transformed Pretransformed coordinates?

I am creating a minecraft like terrain engine thing in XNA and C#, and I am trying to create a item/block selector tool. The thing is I would like to have 3D objects on the tool. So I thought for the ...
2
votes
2answers
901 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 ...
2
votes
2answers
879 views

vertex/pixel shaders and “materials”

What relationship is there, if any, of "materials" and vertex/pixel shaders (or the "effects" that combine the latter two)? I have the impression that before the advent of HLSL, materials were ...
2
votes
2answers
130 views

Problem draw SkyBox behind my sun - XNA

I try to create a small and simple 3D games on XNA. I recently started to add a skyBox after added a sun in my game with the sample by Microsoft here ...
2
votes
2answers
75 views

Linking one uniform variable to many shaders

Let's say, that I have 3 programs, and in each of those programs there is a view matrix uniform, which should be the same in all those programs. Right now, when my camera moves, I need to re-upload ...
2
votes
1answer
417 views

Compute Shader Memory Sharing

Ok guys I have had some pretty good success on this site but I feel that this is a pretty complex question. I am trying to do tile based deferred lighting using DirectX 11 and the compute shader. ...
2
votes
1answer
205 views

Hemispherical Projection

I'm trying to implement a radiosity processor. I'm aware of many places online to find information about radiosity. I found a great source on NVidia's website is GPU Gems - Chapter 39 . On this page ...