loc - Locate and Align Points and Rectangles

loc is a Go library providing types and functions for 2D geometry, focusing on points (Point[S]) and rectangles (Rect[S]).

Overview

The library offers:

• Point[S]: Represents an X, Y coordinate.
• Rect[S]: Represents a rectangle defined by Min and Max points.
• Utility functions for creating points and rectangles (e.g., Xy, Xyxy, Xywh).
• Methods for geometric operations:
  • Point arithmetic (Add, Sub, Mul, Div).
  • Rectangle manipulation (Add, Sub, Inset, Intersect, Union).
  • Alignment (Point.Align, Point.AlignCenter).
  • Cutting and Splitting (Rect.CutX, Rect.CutY, Rect.CutXByRate, Rect.CutYByRate, Rect.SplitX, Rect.SplitY).
  • Repeating (Rect.RepeatX, Rect.RepeatY).
  • Anchoring (Rect.Anchor).

Examples

Basic Point and Rectangle Creation

package main

import (
	"fmt"
	"github.com/eihigh/loc"
)

func main() {
	// Create points
	p1 := loc.Xy(10, 20)
	p2 := loc.Xy(30, 40)
	fmt.Println("Point 1:", p1)
	fmt.Println("Point 2:", p2)

	// Create a rectangle from two points
	rect1 := loc.Xyxy(p1.X, p1.Y, p2.X, p2.Y) // (10,20)-(30,40)
	fmt.Println("Rectangle 1:", rect1)

	// Create a rectangle from position and size
	rect2 := loc.Xywh(0, 0, 100, 50) // (0,0)-(100,50)
	fmt.Println("Rectangle 2:", rect2)
}

Aligning a Rectangle within Another

This example demonstrates aligning a smaller modal rectangle to the center of a larger screen rectangle.

package main

import (
	"fmt"
	"github.com/eihigh/loc"
)

func main() {
	screen := loc.Xyxy(0, 0, 800, 600)
	modal := loc.Xyxy(0, 0, 400, 300)

	// Align 'modal' to the center of 'screen'
	// screen.Center() returns the center Point of the screen.
	// AlignCenter aligns the center of 'modal' to this point.
	alignedModal := screen.Center().AlignCenter(modal)
	fmt.Println("Screen:", screen)
	fmt.Println("Modal (original):", modal)
	fmt.Println("Modal (aligned):", alignedModal)
	// Output: Modal (aligned): (200,150)-(600,450)
}

Cutting a Rectangle

This example shows how to cut a rectangle horizontally by an absolute value and by a rate.

package main

import (
	"fmt"
	"github.com/eihigh/loc"
)

func main() {
	rect := loc.Xyxy(0, 0, 100, 50)

	// Cut by absolute value
	cutAbs, restAbs := rect.CutX(30)
	fmt.Printf("Cut by 30: %s, Rest: %s\n", cutAbs, restAbs)
	// Output: Cut by 30: (0,0)-(30,50), Rest: (30,0)-(100,50)

	// Cut by rate (30% of width)
	cutRate, restRate := rect.CutXByRate(0.3)
	fmt.Printf("Cut by 0.3 rate: %s, Rest: %s\n", cutRate, restRate)
	// Output: Cut by 0.3 rate: (0,0)-(30,50), Rest: (30,0)-(100,50)
}

Repeating a Rectangle

This example demonstrates repeating a rectangle horizontally.

package main

import (
	"fmt"
	"github.com/eihigh/loc"
)

func main() {
	baseRect := loc.Xyxy(0, 0, 20, 30)

	// Repeat 'baseRect' 3 times in X direction with a gap of 5
	repeatedRects, overallRect := baseRect.RepeatX(3, 5)

	fmt.Println("Overall Bounding Box:", overallRect)
	for i, r := range repeatedRects {
		fmt.Printf("Repeated Rect %d: %s\n", i, r)
	}
	// Output:
	// Overall Bounding Box: (0,0)-(70,30)
	// Repeated Rect 0: (0,0)-(20,30)
	// Repeated Rect 1: (25,0)-(45,30)
	// Repeated Rect 2: (50,0)-(70,30)
}

For more detailed examples, please refer to the example_test.go file.