Wrapping (graphics)
Jump to navigation
Jump to search
This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages)
|
In computer graphics, wrapping is the process of limiting a position to an area. A good example of wrapping is wallpaper, a single pattern repeated indefinitely over a wall. Wrapping is used in 3D computer graphics to repeat a texture over a polygon, eliminating the need for large textures or multiple polygons.
To wrap a position x to an area of width w, calculate the value .
Implementation
For computational purposes the wrapped value x' of x can be expressed as
where is the highest value in the range, and is the lowest value in the range.
Pseudocode for wrapping of a value to a range other than 0–1 is
function wrap(X, Min, Max: Real): Real; X := X - Int((X - Min) / (Max - Min)) * (Max - Min); if X < 0 then // This corrects the problem caused by using Int instead of Floor X := X + Max - Min; return X;
Pseudocode for wrapping of a value to a range of 0–1 is
function wrap(X: Real): Real; X := X - Int(X); if X < 0 then X := X + 1; return X;
Pseudocode for wrapping of a value to a range of 0–1 without branching is,
function wrap(X: Real): Real; return ((X mod 1.0) + 1.0) mod 1.0;
See also text wrapping
Categories:
- Articles lacking sources from December 2009
- All articles lacking sources
- Justapedia articles needing context from June 2017
- Articles with invalid date parameter in template
- All Justapedia articles needing context
- All pages needing cleanup
- Articles with multiple maintenance issues
- Computer graphics algorithms