Documentation / Node reference / tex nodes
Makes a picture, or a 3D texture, from code nodes run once for every pixel.
Builder
The code nodes inside run once for each pixel of the output, and the tex/Output inside says its colour and alpha. code/Globals gives what changes from one pixel to the next: UV, the centre of the pixel being written, from 0 to 1 across the picture. With nothing else wired, a new builder shows a UV gradient.
Up to four pictures can be wired into the builder. Read one with a code/TextureInput: code/TextureTexel reads its pixels exactly, at the pixel being written or next to it, and code/TextureSample2D with a code/Sampler reads it between pixels. code/Globals' InputColor is the picture on input 0 at the pixel being written. A simulation step reads its picture this way, inside a tex/Solver.
With nothing wired into input 0 the builder makes something new, at the size its params say. dimension _2D makes a picture of resolution2D pixels. dimension _3D makes a 3D texture of resolution3D voxels, a block of values you can look at slice by slice in the texture panel: code/Globals then gives uvw, the centre of the voxel being written, from 0 to 1 on each axis, and VoxelPosition, the voxel's whole-number position. A 3D texture is at most 256 voxels on each axis: above that the builder makes it 256 and warns. A 3D output has no mipmaps.
With a picture or a 3D texture wired into input 0, the output takes its dimension and its size, and dimension and both resolutions are greyed out. A 3D input larger than 256 on an axis gives a smaller output, with a warning; the input is read as it is, never resized.
A 3D builder can read 2D pictures on its other inputs, a gradient used as a lookup for example, at the uvw's first two values. A 2D builder cannot read a 3D texture: wiring one into a 2D builder and reading it is refused, with a message naming the input.
| Name | Type | What it does |
|---|---|---|
| dimension | UInt8 UNKNOWN · _1D · _2D · _3D | What the builder makes when nothing is wired into input 0. _2D: a picture of resolution2D pixels. _3D: a 3D texture of resolution3D voxels. Greyed out while input 0 is wired, since the output then takes input 0's dimension. |
| resolution2D | Vector2UInt | The size of the picture in pixels, width then height, when dimension is _2D. Greyed out while input 0 is wired, since the output then takes input 0's size. |
| resolution3D | Vector3UInt | The size of the 3D texture in voxels, on x, y and z, when dimension is _3D. At most 256 on each axis: a larger value is made 256 and the builder warns. Greyed out while input 0 is wired, since the output then takes input 0's size. |
| outputFormat | UInt8 RGBA8Unorm · RGBA16Float · RGBA32Float | How each pixel is stored. RGBA8Unorm: 8 bits a channel, for colours to show (the values are clamped to 0 to 1). RGBA16Float: 16-bit floats, for values outside 0 to 1, an environment map or a simulation. RGBA32Float: 32-bit floats, for the most precision; another tex/Builder cannot read it, so convert it to 16-bit floats first. |
| generateMipmaps | Bool | Also make the smaller copies of the picture a material reads from a distance. 2D only. |
| mipmapsFilter | UInt8 Box · EnvironmentGGX | How the smaller copies are made. Box: each averages four pixels of the one before. EnvironmentGGX: blurred for rougher reflections, for a picture used as an environment map. |
Scenes you can open in the editor that teach this node.
A tex/Builder set to _3D makes a 64 by 64 by 64 texture from code nodes: from code/Globals' UVW, the distance to three centres, softened at each sphere's edge, the largest of the three kept. Open the texture panel to see it slice by slice or raymarched. geo/VolumeFromTexture brings it into the viewer as a volume, rendered as fog on one side and meshed on the other.
tex/Builder code/Globals tex/Output geo/VolumeFromTexture
A gradient and an ellipse wired into a tex/Builder: inside the ellipse the gradient's colours are inverted, outside they are kept. code/Globals' InputColor reads the gradient pixel for pixel; code/TextureInput gives the ellipse as a texture, which code/TextureSample2D samples.
tex/Builder code/TextureInput code/Globals
The tex/ReactionDiffusion node grows coral from a few blobs. A map changes the feed and the kill from left to right, so the blobs stay rings and dots on the left and branch into dense coral on the right, and a mask blocks a round rock in the middle, which the coral grows around.
tex/PolyNode tex/Builder code/Noise
The tex/ReactionDiffusion node grows a pattern from a star seeded in a picture: two chemicals spread and react, and the star becomes a maze of stripes. Other values of F and k give coral, worms, spots and holes.
tex/PolyNode tex/Solver tex/Builder code/TextureLaplacian
The tex/ReactionDiffusion node grows a pattern in a 64 by 64 by 64 texture: two chemicals spread through the volume and react, and three seeded spheres grow into a maze of folded sheets. The viewer draws them as fog with a mat/Volume, and beside it as a solid with a mat/VolumeSurface, both reading the texture where the GPU wrote it. Open the texture panel to see it slice by slice or raymarched.
tex/PolyNode tex/Solver tex/Builder code/TextureLaplacian mat/Volume mat/VolumeSurface
This page is generated from the engine, so it describes the release you can download. The same text is in the editor's Help panel next to the node itself.
