GIG reference manual

intercol maps

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Section contents

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Introduction

In the literature, the terms "texture" and "maps" are used interchangeably. However there is a clear difference in meaning when we use these terms in this manual. By adding attributes to a solid in GIG we define the matter or material of that object. The combination of these attributes (together with maps) defines what we call the "texture" of an object. It is what we see and interpret as the substance the object is made of. A "map" (or procedural map), on the other hand, is a function. It is not directly visible. However, functions can be made visible through the attributes. For example, a diffuse attribute that is added to a solid consists of some parts such as an intensity value and a color. These parts can be replaced by a map of the same type.

Procedural maps should not be confused with file maps such as can be found in the maps directory in GIG. File maps in the map directory might be scanned images, images created with some kind of paintbox, and/or rendered images by GIG itself. These maps are added to an attribute of an object in a different way. Although there is no difference conceptually between the two types of maps, you might notice differences in two ways:

First, when you save a still with file maps, the filename will be saved. But when the still is copied to another project to be rendered, the actual file map will not be copied with it. A procedural map will be saved together with a still like any normal attribute.

The second difference might be noticed during rendering. A fairly complex procedural map is arithmetically intensive. Rendering an object with such a map will take more time than with a file map. A procedural map is defined by the coordinates of an object. It is independent of the scale of an object, and there will be no loss of detail. On the other hand, a file map will be interpolated on an object, so that scaling the object and the map will have consequences for detail.

The map text input box offers a way to create new maps. These maps might be used in the Texture Editor next to the predefined maps in the maps listbox. This combination was previously done with the intercol language through the attribute menu. With the Texture Editor this has become more easier.

The way new maps are created is done by using the map functions that are listed in the Appendix in a mathematical expression. Some knowledge of mathematics is required to fully understand and use this manual. However, the examples in the reference manual, the Appendix and tutorials should put you on your way.