New constructor syntax in README.md

Signed-off-by: John McCutchan <john@johnmccutchan.com>
1 file changed
tree: cc00dd27137a6d3f42439ae5ef0ba02ac653ebd9
  1. lib/
  2. test/
  3. tool/
  4. .gitignore
  5. AUTHORS.txt
  6. ChangeLog.txt
  7. LICENSE.txt
  8. pubspec.yaml
  9. README.md
  10. VERSION.txt
README.md

vector_math

Introduction

A Vector math library for 2D and 3D applications.

Features

  • 2D,3D, and 4D vector and matrix types.
  • Quaternion type for animating rotations.
  • Syntax that is practically identical to GLSL the WebGL shader language.
    • Flexible getters and setters, for example, position.xwz = color.grb;
    • All GLSL utility functions
    • Flexible construction new vec3(new vec2(x,y), z);
  • Fully documented
  • Well tested
  • Heavily optimized

Status: Beta

Getting Started

Create a new Dart project and add the following to pubspec.yaml

dependencies:
  vector_math:
    git: https://github.com/johnmccutchan/DartVectorMath.git

Add the correct import to your project.

If your project depends on dart:io:

import 'package:vector_math/vector_math_console.dart';

If your project depends on dart:html:

import 'package:vector_math/vector_math_browser.dart';

Example

1. Using the GLSL getter and setter syntax.

void main() {
	vec3 x = new vec3(); // Zero vector
	vec4 y = new vec4(4.0); // Vector with 4.0 in all lanes
	x.zyx = y.xzz; // Sets z,y,x the values in x,z,z
}

2. Transforming a vector.

void main() {
	// Rotation of pi/2 degrees around the Y axis followed by a 
	// translation of (5.0, 2.0, 3.0).
	mat4 T = new mat4.rotationY(pi*0.5).translate(5.0, 2.0, 3.0);
	// A point.
	vec3 position = new vec3.raw(1.0, 1.0, 1.0);
	// Transform position by T.
	T.transform3(position);
}

3. Invert a matrix

void main() {
	// Rotation of 90 degrees around the Y axis followed by a 
	// translation of (5.0, 2.0, 3.0).
	mat4 T = new mat4.rotationY(pi*0.5).translate(5.0, 2.0, 3.0);
	// Invert T.
	T.invert();
	// Invert just the rotation in T.
	T.invertRotation();
}

4. Rotate a vector using a quaternion

void main() {
	// The X axis.
	vec3 axis = new vec3.raw(1.0, 0.0, 0.0);
	// 90 degrees.
	double angle = pi/2.0;
	// Quaternion encoding a 90 degree rotation along the X axis. 
	quat q = new quat.axisAngle(axis, angle);
	// A point.
	vec3 point = new vec3.raw(1.0, 1.0, 1.0);
	// Rotate point by q.
	q.rotate(point);
}