Crate emath

Expand description

Opinionated 2D math library for building GUIs.

Includes vectors, positions, rectangles etc.

Conventions (unless otherwise specified):

emath does not strive to become a general purpose or all-powerful math library.

For that, use something else (glam, nalgebra, …) and enable the mint feature flag in emath to enable implicit conversion to/from emath.

bytemuck — bytemuck enables you to cast emath types to &[u8].
document-features — Enable this when generating docs.
mint — mint enables interoperability with other math libraries such as glam and nalgebra.
serde — Allow serialization using serde.

Re-exports§

align: One- and two-dimensional alignment (Align::Center, Align2::LEFT_TOP etc).
easing: Easing functions for animations.
smart_aim: Find “simple” numbers is some range. Used by sliders.

History: This struct tracks recent values of some time series.
OrderedFloat: Wraps a floating-point value to add total order and hash. Possible types for T are f32 and f64.
Pos2: A position on screen.
Rangef: Inclusive range of floats, i.e. min..=max, but more ergonomic than RangeInclusive.
Rect: A rectangular region of space.
RectTransform: Linearly transforms positions from one Rect to another.
Rot2: Represents a rotation in the 2D plane.
TSTransform: Linearly transforms positions via a translation, then a scaling.
Vec2: A vector has a direction and length. A Vec2 is often used to represent a size.
Vec2b: Two bools, one for each axis (X and Y).

GUI_ROUNDING: We (sometimes) round sizes and coordinates to an even multiple of this value.

Float: Extension trait to provide ord() method.
GuiRounding: Trait for rounding coordinates and sizes to align with either .
NumExt: Extends f32, Vec2 etc with at_least and at_most as aliases for max and min.
Numeric: Implemented for all builtin numeric types
One: Helper trait to implement lerp and remap.
Real: Helper trait to implement lerp and remap.

almost_equal: Return true when arguments are the same within some rounding error.
ease_in_ease_out: Ease in, ease out.
exponential_smooth_factor: Calculate a lerp-factor for exponential smoothing using a time step.
format_with_decimals_in_range: Use as few decimals as possible to show the value accurately, but within the given range.
format_with_minimum_decimals
interpolation_factor: If you have a value animating over time, how much towards its target do you need to move it this frame?
inverse_lerp: Where in the range is this value? Returns 0-1 if within the range.
lerp: Linear interpolation.
normalized_angle: Wrap angle to [-PI, PI] range.
pos2: pos2(x, y) == Pos2::new(x, y)
remap: Linearly remap a value from one range to another, so that when x == from.start() returns to.start() and when x == from.end() returns to.end().
remap_clamp: Like remap, but also clamps the value so that the returned value is always in the to range.
round_to_decimals: Round a value to the given number of decimal places.
vec2: vec2(x, y) == Vec2::new(x, y)