Image use for mapping:
- tif: TIFF (Tagged Image File Format)
- rgb: Silicon Graphics 24-bit RGB color
- bmp: Microsoft Windows Bitmap Format
- jpg: JPEG (Joint Photographic Experts Group)
- pic: Apple Macintosh Format
- psd: Photoshop Format
- png: Portable Network Graphics
- tga: Truevision Targa file format
- HLS (Hue, Saturation, Luminance) model is an intuitive, easy to use tool for describing or modifying a color.
- Hue is the “color” of the color. It is the name by which the color is designated and is used to define the desired color.
- Saturation is the intensity of the color. The higher the number, the more intense the color. It is used to tune the purity of the color.
- Luminance is the brightness of the color, i.e. the degree to which the pure color is diluted by white or black. The larger the number, the lighter the color. It is used to adjust intensity
- RGB (Red, Green, Blue) model is a more physical model. It is based on the tri-stimulus theory of the human perception system. This model is usually used to define, with a high precision, the three primary components of the color.
- Ambient: the intensity of light diffused in any direction by the object, even if not lit by any light source. The ambient light is essentially used to show objects or parts of objects that are not illuminated directly by the light source. This parameter affects the whole object, including the shadowed area. The intensity is defined by a coefficient (with a value between 0 and 1).
- Diffuse: the intensity of light diffused by the object when lit by light sources.
Typically, a shiny metal surface would have a diffuse reflectance value close to 0, while a piece of cardboard would have a value probably above 0.9.The intensity is defined by a coefficient (with a value between 0 and 1). - Specular: intensity and color of light reflected in one particular direction (highlights) Set the value to a minimum to generate very sharp highlights on very shiny surfaces. Set the shininess to a higher value to generate large specular spots creating a duller effect. Typically, a polished object would have a high value for the specular reflectance coefficient, while a more mat surface would have a lower one.
- Roughness: dullness of an object (size of the reflecting zone). Set the value to a minimum to generate very sharp highlights on very shiny surfaces. Set the shininess to a higher value to generate large specular spots creating a duller effect on rougher surfaces.
- Transparency: degree of transparency of an object and color of the filter interfering with the light passing through an object. The transparency color acts like a photographic filter which modifies artificially the light rays received by an optical lens. It is generally identical to the ambient and diffuse color but when it is different, the shadows cast by the object are colored accordingly. For instance, a blue object with a red transparency color will cast slightly red shadows. The higher the value, the more transparent the object (in the example the value is 0.75), the lower the value, the more opaque the object.
- Refraction: degree of light passing obliquely through an object. The refraction is defined by a coefficient (value between 1 and 2).Set to 1, the transparent object will show no light distortion.As an example, water has a 1.2 coefficient. This parameter is relevant for software rendering only.
- Reflectivity: degree of reflectivity of an object. Set to a high value, the object reflects its environment.Set this parameter to 0.2 in order to see the reflections when a texture is applied. Otherwise, set this parameter to a value greater than 0 to see the texture.