Questions tagged [fragment-shader]

A GPU program used in rendering. It is executed for each sample taken from a rasterized primitive. The output of this process is a number of values and a floating-point depth.

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Fragment Shader

1506 questions

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1 answer

How do I render a subset of a texture (knowing the size in pixels) in a OpenGL/WebGL Fragment Shader?

I've got some code that is rendering 2D sprites to the screen. It all works; but the texture coords are provided in the range 0,0 - 1,1. I would like to supply the coordinates in pixels, so that when I'm creating a sprite, I can provide the part of…

asked Oct 11 '14 at 11:36

Danny Tuppeny

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1 answer

Transparency in Three.js ShaderMaterial fragment shader

I've used Three.js quite a bit, but I'm just starting to learn how shaders work. I have a green cube which is one-half transparent, as defined in a THREE.ShaderMaterial (based on the "phong" ShaderLib). I put a simple red cube inside the…

three.js webgl fragment-shader

asked Oct 08 '14 at 18:54

TheJim01

8,411
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Inconsistency with small custom WebGL shaders under linux with Three.js

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 warcluster-shaders-ubuntu && warcluster-shaders-archlinux in the same…

linux three.js webgl fragment-shader vertex-shader

asked Oct 02 '14 at 19:36

Виталий Филипов

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0 answers

Insanely slow ray tracer

I've started working on a ray tracer recently, and even though I got it working pretty well, I soon ran into some trouble. I'm trying to simulate a park, and I basically have one single DistanceFromPoint(vec3 p) function that calculates the distance…

opengl glsl fragment-shader raytracing

asked Sep 29 '14 at 16:30

user3541787

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2 answers

LWJGL Texture loading / mapping issue

I'm drawing a quad with a 512 x 512 texture composed of 4 squares with 4 different colors (yellow, blue, green, red). When i look at the image it's all yellow but the tex coords space from 0 to 1 and i'm quite sure they're mapped correctly... here's…

java opengl lwjgl texture-mapping fragment-shader

asked Sep 27 '14 at 19:50

Mk3Y

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1 answer

fast 2D texture line sample

Imagine you have a chessboard textured triangle shown in front of you. Then imagine you move the camera so that you can see the triangle from one side, when it nearly looks as a line. You will provably see the line as grey, because this is the…

graphics textures fragment-shader

asked Sep 27 '14 at 00:45

Inuart

1,432
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1 answer

GLSL normal map lighting dark areas and light facing odd direction

I can't seem to figure out why my fragment and vertex shaders aren't working. I think I either have my view/perspective wrong, or maybe my normal map has negative values (since black is showing up lit). Either way, I've been at this for days and I…

opengl glsl fragment-shader lighting vertex-shader

asked Sep 23 '14 at 03:27

justaguy

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2 answers

How to make a fragment shader replace white with alpha, opengl-es

I am trying to come up with a opengl-es fragment shader that will replace the white pixels with alpha. The image with the checkered background is what I want. The checkered background represents the image after alpha conversion. Any tips? Normally…

opengl-es fragment-shader

asked Sep 17 '14 at 23:43

NJGUY

2,045
3
23
43

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Math.random() undeclared identifier

I am trying to generate random colors in my fragment shader, but I'm running into compiler errors. Here is my code: