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Questions tagged [volume-rendering]

In the case of Direct Volume Rendering (DVR), a transfer function (TF) maps the raw volume data to optical properties needed for image synthesis, e.g. from opaque black and white images to translucent and coloured results.

In the case of indirect rendering methods, opaque surfaces get extracted by preprocessing the raw volume data, e.g. resulting in isosurfaces.

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create cylinders in 3D volumetric data

I'm trying to create a dataset of raw volumetric data consisting of geometrical shapes. The point is to use volume ray casting to project them in 2D but first I want to create the volume manually. The geometry is consisting of one cylinder that is…
George Aprilis
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Read raw 3D texture and slice cube

Reading a raw 3d (256x256x256 cells) texture (8bit) using the following: f = fopen(file, "rb"); if (f == NULL) return; int size = width * height * depth; data = new unsigned char[size*3]; fread(data, 3, size, f); image = reinterpret_cast
toeplitz
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How best to create a filled volume of Lorenz Attractor in python for volume rendering

I am trying to create a 3D array to then perform volume rendering on (in other software or volume rendering packages) of strange attractor like Lorenz Attractor. It is easy enough to plot the attractor from data points and provide a value to assign…
Robin White
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GPU ray casting (single pass) with 3d textures in spherical coordinates

i' am implementing an algorithm of volume rendering "GPU ray casting single pass". For this, i used a float array of intensity values as 3d textures ( this 3d textures describes a regular 3d grid in spherical coordinates ). Here there are example of…
sebastian pinto
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OpenGL How to calculate worldspace coordinates from frustum aligned vectors?

I am a graphics programming beginner working on my own engine and tried to implement frustum-aligned volume rendering. The idea was to render multiple planes as vertical slices across the view frustum and then use the world coordinates of those…
Blendurian
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Volume reconstruction from 3D image gradient in Matlab

For 2D images- Gx and Gy gives the information on vertical and horizontal edge infromation respectively. Angle of the gradient direction vector can be calculated from inverse of tan(Gy/Gx) and edge direction will be perpendicular to the gradient…
Maharshi
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Writing to an empty 3D texture in a Compute Shader

I am attempting to create an empty 3D texture, the dimensions and format of which are loaded in at runtime. I then want to modify the values of this texture, which I am then volume rendering with a ray tracer. I know my rendering function works…
Strawhare
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Unity 3D textures - Loading 2D Texture Array

I'm having an issue creating a 3D texture and filling it with images. What I want to do is creating a Volumetric/3D texture with the RGBA values of my images, and put it in order in the texture. In order to do this, I create a Cube, and apply this…
Bitelchús
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VTK - Volume Rendering from a Rectilinear Grid

I'm developing a C++ application that uses VTK for some visualization. I need to read a .vtr file (RectilinearGrid) and render it using VTK volume rendering features.I tried to do that with Paraview and it was VERY easy, I just had to apply a…
Oneiros
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Volume rendering from inside volume

We've been doing lots of work trying to volume render 3D cloud fields in WebGL. The approach we've taken so far is outlined here - the start position of each ray is the current position in the front face of the volume cube, and the end position is…
nrob
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Volume rendering artefacts when looking along the z-plane

I've been trying to get some WebGL volume rendering up and running. I've managed to tile 3D data to a 2D texture (tiling both laterally and along the RGB channels). And it now displays some synthetic data (a sphere). When viewed along the x,y planes…
nrob
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Apply transformation to faces/vertices from isosurface and plotting the result

If I have a contour in Matlab obtained [f, v] = isosurface(x, y, z, v, isovalue) is there a clean way to apply a transformation to the surfaces and nicely plot the result as a smooth surface? The transformation T is nonlinear. I tried to apply…
db1234
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Write A simple raycast shader

I want to do a simple single-pass raycast shader. That is, i pass the vertex's world position in vertexshader, and in fragment shader start ray marching to Z axis(i use ortho projection) to get sample position in world coordinate, then i need to…
user2535400
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Multi-Texturing - Interpolation between two layers of an 3D texture

I'm trying to achieve terrain texturing using 3D texture that consists of several layers of material and to make smooth blending between materials. Maybe my illustration will explain it better: Just imagine that each color is a cool terrain…
RaZeR RawByte
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Volume ray casting doesn't work fine (Webgl + GLSL + Three.js)

I have tried to make better quality of my volume ray casting algorithm. I have set a smaller step of raycast (quality is better), but it causes problem. It is on pictures below (black areas where they shouldnt be). I am using RGB cube to get…
Xrew
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