Textures in Ray-tracing

Plain sphere

Checker color texture

Mandelbrot color texture

Earth surface texture

Bump texture

Earth texture bitmap (large)

Elevation bitmap

Elevation-based colormap

Noise generator (sparse convolution)

Convolution radial function ƒ = (cos(r/π)+1)/2 (kernel radius is 1).
Constant number of samples in one square/cube cell 1x1/1x1x1 is generated.

Plain noise

Cell: 50x50, samples: 2/cell = 2π/supp(ƒ)

Cell: 50x50, samples: 3/cell

Cell: 50x50, samples: 6/cell

Cell: 50x50, samples: 10/cell

Cell: 20x20, samples: 6/cell

Cell: 8.3x8.3, samples: 6/cell

Cell: 3.3x3.3, samples: 6/cell

Turbulence

Sum of a sequence of noise values with increasing frequency and decreasing amplitude.

Cell: 50x50, 2 comp, coeff: 0.5

Cell: 50x50, 4 comp, coeff: 0.5

Cell: 42.5x42.5, 6 comp, coeff: 0.7

Cell: 42.5x42.5, 7 comp, coeff: 0.7/0.8

Noise-based textures

Color 2D texture, spherical mapping

2D bump-map, spherical mapping

Anisotropic bump-map, spherical mapping

Color + bump map, spherical mapping

3D cell texture (cubic)

3D cell texture (hexagonal)

Water surface simulation

Empirical modelling using continuous noise functions to modulate surface normals. Caustics were computed by light-tracing preprocessing steps. One rectangular uniform light source (on vertical wall behind the pool) was sampled by 11.8 million of light-rays per image. Light map on the pool bottom had 512x512px resolution.

Light-map, medium waves

Light-map, strong waves

Pool, light waves

Pool, medium waves

Pool, strong waves

Flame simulation

Empirical 2D flame simulation is based on deforming a base flame image by a suitable continuous noise function. Animation is introduced using 3D noise, drifting slowly along a sloped direction.

Base image

Flame, light turbulence

Flame, medium turbulence

Flame, strong turbulence

Flame-animation
Flame animation, snapshots from one animation sequence