Image textures are two dimensional images that are projected on 3D objects. These textures can be used in a variety of material channels, for example color and bump. Typically, the UV mapping of images on 3D objects is handled by the 3D application.
The following formats can be used as textures:
- BMP (uncompressed)
- HDR (Analyze 7.5)
- RAW (consisting of a very simple header (in ascii), then the image data)
- ASC (Ascii)
- INR (Inrimage)
- PPM/PGM (Portable Pixmap)
- PAN (Pandore-5)
- DLM (Matlab ASCII)
In most cases, PNG files work best for texturing in LuxCoreRender. TIF and PSD (Photoshop) images may work on some platforms.
Image Texture Parameters
When using an image as a texture in any material channel, a couple of parameters are available:
- Gamma - The gamma correction value for the texture. 1.0 will not affect the texture, which is what you want when you need to use the actual RGB values encoded into the texture, such as for a bump map or specular map. If you want a color image texture to appear as the image did on screen, you will want to set this to the screen gamma it was built using, which is probably 2.2.
- Gain - A scaling factor that will be applied to the image.
Procedural textures are defined mathematically, which means that the texture value (or color) at any given point is calculated by the program instead of being defined by an existing bitmap image. By combining various textures, very complex materials can be created. At the same time, using procedural textures can be very time effective since UV mapping is not required. Many of the procedural textures are fully three dimensional, which means that regardless of the shape of an object, they will always fit perfectly at edges.
The downside of having LuxCoreRender calculate the texture's values is that your 3D application may not be able to show previews for all textures. More complex procedural textures can also add to the render time.
The spectrum textures are a set of color textures that define an actual light spectrum rather than an RGB color. They are mainly used for absorption and emission, but can be used on any color field if desired.
For more information, see LuxCoreRender's spectrum textures