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diff --git a/debian/fireflies/fireflies-2.08/libgfx/doc/vec.html b/debian/fireflies/fireflies-2.08/libgfx/doc/vec.html new file mode 100644 index 00000000..f62aa29d --- /dev/null +++ b/debian/fireflies/fireflies-2.08/libgfx/doc/vec.html @@ -0,0 +1,125 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" + "http://www.w3.org/TR/REC-html40/loose.dtd"> +<!-- $Id: vec.html 289 2002-01-14 18:21:43Z garland $ --> + +<html> + +<head> +<title>libgfx: Vector Math</title> +<link rel=stylesheet href="cdoc.css" type="text/css"> +<meta name="Author" content="Michael Garland"> +</head> + +<body> + +<h2>Vector Math</h2> + +<p>The <tt>libgfx</tt> vector math package provides classes that +make it much more convenient to write vector equations. +Two dimensional [<a href="vec2.html">Vec2</a>], +three dimensional [<a href="vec3.html">Vec3</a>], +and four dimensional [<a href="vec4.html">Vec4</a>] +vector classes are provided. + +<p>A vector consists of <i>n</i> numeric values. These vector types are +actually implemented using template classes such as <tt>TVec3<class +T></tt> that allow the application to specify the type of value used to +represent the vector elements. The standard classes described in this +documentation (<tt>Vec2</tt>, <tt>Vec3</tt>, and <tt>Vec4</tt>) use double +precision floating point values. Corresponding classes using single precision +floating point values (<tt>Vec2f</tt>, <tt>Vec3f</tt>, and <tt>Vec4f</tt>) are +also provided. + +<p>The elements of a vector are accessed with the standard bracket notation +used for arrays. And like C++ arrays, vectors are indexed starting from 0. +Thus the elements of a 3-vector can be assigned as follows: + +<pre> + Vec3 v; + + v[0] = 1.0; + v[1] = 0.0; + v[2] = 2.0; +</pre> + +The default constructors (as used in the previous example) always +initialize the vector elements to 0. All vector classes also provide +constructors which accept the initial element values as arguments. +Thus the previous example could be more succinctly written as: + +<pre> + Vec3 v(1.0, 0.0, 2.0); +</pre> + +Vectors can also be automatically cast to <code>double</code> pointer +types. Continuing the preceding example, the following is perfectly legal: +<pre> + double *w = v; <i>// w points to the first element of v</i> + w[1] = 3.14; <i>// Exactly equivalent to v[1] = 3.14</i> +</pre> + +<p><strong>Warning:</strong> +For efficiency reasons, <em>accessors are not range checked</em>. +Thus you can legally write + +<pre> + Vec3 v; + v[42] = 3.14159; +</pre> + +and this will cause an invalid memory access beyond the bounds of the +vector. This may cause a memory fault or it may just silently +over-write other data. Therefore you must make sure that you only +access valid elements of arrays. + + +<h3>Arithmetic Operators</h3> + +<p>One of the primary goals of the vector package is to simplify the +coding of vector equations. To accomplish this, it makes use of +<em>operator overloading</em>. + + +<p><strong>Assignment</strong> +Vectors can be assigned the values of other vectors or scalars. +A vector assignment <tt>v = w</tt> copies the elements of <tt>w</tt> +into the corresponding elements of <tt>v</tt>. A scalar assignment +<tt>v = 1.0</tt> copies the given scalar, in this case <tt>1.0</tt>, +into each of the elements of <tt>v</tt>. + +<p><strong>Addition/Subtraction</strong> Vectors can be +added together either with the binary addition operator (<tt>u = v + +w</tt>) or the additive assignment operator (<tt>u += v</tt>). +Subtraction operates similarly, using subtraction rather than addition +operators. + +<p><strong>Scalar Multiplication/Division</strong> +Vectors can be multiplied by scalar values using either the binary +operator (<tt>v * 2.0</tt>) or the accumulation operator (<tt>v *= +2.0</tt>). Scalar division operates similarly. + +<p><strong>Inner Product</strong> +The inner product (or dot product) of two vectors is written with the +standard multiplication operator: <tt>v * w</tt>. + +<h3>Standard Vector Functions</h3> + +<p>All vector classes support a standard set of functions for +performing common operations on vectors. These functions are: +<pre> + <i>// Returns the squared length of the vector v</i> + inline double norm2(const Vec_& v); + + <i>// Returns the length of the vector v</i> + inline double norm(const Vec_& v); + + <i>// Adjusts v to have unit length. Mostly equivalent to v/=norm(v)</i> + inline void unitize(Vec_& v); +</pre> + +<p>Vector can also be read from and written to C++ iostreams using the +standard <tt><<</tt> and <tt>>></tt> operators. + +</body> + +</html> |