transformator

A Rust library for CSS-style 3D transform composition and inheritance. Compose hierarchical transforms with support for perspective, rotations, translations, scaling, and transform origins - just like CSS transforms work in browsers.

Features

• CSS-like transform composition: Chain transforms using familiar patterns (translate, rotate, scale)
• Hierarchical inheritance: Child transforms automatically inherit and compose with parent transforms
• Perspective support: Apply CSS-style perspective with customizable origin
• Hit testing: Project screen coordinates back to local space for accurate hit detection
• Optional serialization: Enable serde support with the serialization feature

Installation

[dependencies]
transformator = "0.1"

# With serialization support
transformator = { version = "0.1", features = ["serialization"] }

Usage

Basic Transform Composition

use transformator::Transform;

// Create a root transform (identity)
let root = Transform::new();

// Create a parent with position, perspective, origin, and rotation
let parent = Transform::new()
    .with_position_relative_to_parent(350.0, 250.0)
    .with_parent_container_perspective(500.0, 400.0, 300.0)
    .with_origin(50.0, 50.0)  // Rotate around center of 100x100 element
    .then_rotate_x_deg(45.0)
    .compose_2(&root);

// Create a child that inherits parent's transform
let child = Transform::new()
    .with_position_relative_to_parent(10.0, 10.0)
    .compose_2(&parent);

// Transform local points to world coordinates
let world_pos = parent.transform_local_point2d_to_world(0.0, 0.0);

Chaining Multiple Transforms

let transform = Transform::new()
    .with_position_relative_to_parent(100.0, 100.0)
    .with_origin(50.0, 50.0)
    .then_rotate_y_deg(30.0)
    .then_rotate_x_deg(45.0)
    .then_translate(10.0, 20.0)
    .then_scale(1.5, 1.5)
    .compose_2(&Transform::new());

Hit Testing (Screen to Local Coordinates)

// Project mouse position to local coordinates for hit testing
if let Some((local_x, local_y)) = transform.project_screen_point_to_local_2d((mouse_x, mouse_y)) {
    // Check if point is inside your shape in local space
    if local_x >= 0.0 && local_x <= 100.0 && local_y >= 0.0 && local_y <= 100.0 {
        println!("Hit!");
    }
}

Available Transform Methods

Method	Description
translate(x, y) / then_translate(x, y)	2D translation
translate_3d(x, y, z) / then_translate_3d(x, y, z)	3D translation
rotate_x_deg(deg) / then_rotate_x_deg(deg)	Rotate around X axis
rotate_y_deg(deg) / then_rotate_y_deg(deg)	Rotate around Y axis
rotate_z_deg(deg) / then_rotate_z_deg(deg)	Rotate around Z axis
scale(sx, sy) / then_scale(sx, sy)	2D scaling
scale_3d(sx, sy, sz) / then_scale_3d(sx, sy, sz)	3D scaling
with_origin(x, y)	Set transform origin (pivot point)
with_position_relative_to_parent(x, y)	Set position relative to parent
with_parent_container_perspective(dist, ox, oy)	Set perspective
compose(&parent) / compose_2(&parent)	Compose with parent transform

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.