A Vector math library for 2D and 3D applications.
position.xwz = color.grb;.1. Using the GLSL getter and setter syntax.
import 'package:vector_math/vector_math.dart'; void main() { Vector3 x = Vector3.zero(); // Zero vector Vector4 y = Vector4.all(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.
import 'dart:math'; import 'package:vector_math/vector_math.dart'; void main() { // Rotation of PI/2 degrees around the Y axis followed by a // translation of (5.0, 2.0, 3.0). Matrix4 T = Matrix4.rotationY(PI * 0.5)..translate(5.0, 2.0, 3.0); // A point. Vector3 position = Vector3(1.0, 1.0, 1.0); // Transform position by T. T.transform3(position); }
3. Invert a matrix
import 'dart:math'; import 'package:vector_math/vector_math.dart'; void main() { // Rotation of 90 degrees around the Y axis followed by a // translation of (5.0, 2.0, 3.0). Matrix4 T = Matrix4.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
import 'dart:math'; import 'package:vector_math/vector_math.dart'; void main() { // The X axis. Vector3 axis = Vector3(1.0, 0.0, 0.0); // 90 degrees. double angle = PI / 2.0; // Quaternion encoding a 90 degree rotation along the X axis. Quaternion q = Quaternion.axisAngle(axis, angle); // A point. Vector3 point = Vector3(1.0, 1.0, 1.0); // Rotate point by q. q.rotate(point); }
5. Check if two axis aligned bounding boxes intersect
import 'package:vector_math/vector_math.dart'; void main() { // Define the first box with a minimum and a maximum. Aabb2 aabbOne = Aabb2.minMax(Vector2.zero(), Vector2(4.0, 4.0)); // Define the second box Aabb2 aabbTwo = Aabb2.minMax(Vector2(5.0, 5.0), Vector2(6.0, 6.0)); // Extend the second box to contain a point aabbTwo.hullPoint(Vector2(3.0, 3.0)); // Check if the two boxes intersect, returns true in this case. bool intersect = aabbOne.intersectsWithAabb2(aabbTwo); }
6. Check where a ray and a sphere intersect
import 'package:vector_math/vector_math.dart'; void main() { // Define a ray starting at the origin and going into positive x-direction. Ray ray = Ray.originDirection(Vector3.zero(), Vector3(1.0, 0.0, 0.0)); // Defines a sphere with the center (5.0 0.0 0.0) and a radius of 2. Sphere sphere = Sphere.centerRadius(Vector3(5.0, 0.0, 0.0), 2.0); // Checks if the ray intersect with the sphere and returns the distance of the // intersection from the origin of the ray. Would return null if no intersection // is found. double distanceFromOrigin = ray.intersectsWithSphere(sphere); // Evaluate the position of the intersection, in this case (3.0 0.0 0.0). Vector3 position = ray.at(distanceFromOrigin); }
7. Work with colors
import 'package:vector_math/vector_math.dart'; void main() { // Access a build-in color, colors are stored in 4-dimensional vectors. Vector4 red = Colors.red; Vector4 gray = Vector4.zero(); // Convert the red color to a grayscaled color. Colors.toGrayscale(red, gray); // Parse a blue color from a hex string. Vector4 blue = Vector4.zero(); Colors.fromHexString('#0000FF', blue); // Convert the blue color from RGB to HSL. Colors.rgbToHsl(blue, blue); // Reduce the lightness of the color by 50%. blue.z *= 0.5; // Convert the HSL color back to RGB. Colors.hslToRgb(blue, blue); }
8. Use 64bit float precision (instead of 32bit)
// Use different import statement. // Which is a drop-in replacement for 'package:vector_math/vector_math.dart' import 'package:vector_math/vector_math_64.dart'; void main() { // Types work the same, but using 64 bit storage. Vector3 x = Vector3.zero(); Matrix4 m = Matrix4.identity(); }
To run the unit tests:
~/src/vector_math/> dart test
To automatically generate the latest version of vector_math_64:
~/src/vector_math/> dart tool/generate_vector_math_64.dart