util.go

package ui

import (
	"github.com/deadsy/sdfx/sdf"
	"github.com/deadsy/sdfx/vec/conv"
	v2 "github.com/deadsy/sdfx/vec/v2"
	"github.com/deadsy/sdfx/vec/v2i"
	"github.com/hajimehoshi/ebiten"
	"github.com/hajimehoshi/ebiten/text"
	"golang.org/x/image/font/inconsolata"
	"image/color"
	"math"
	"runtime"
)

func utilSdf2MinMax(s sdf.SDF2, bb sdf.Box2, cells v2i.Vec) (dmin, dmax float64) {
	cellSize := bb.Size().Div(conv.V2iToV2(cells))
	for x := 0; x < cells.X; x++ {
		for y := 0; y < cells.Y; y++ {
			// TODO: Reverse raycast (without limiting to a single direction) to find extreme values instead of 0s
			//  (should lower sample count for same results)
			pos := bb.Min.Add((v2.Vec{X: float64(x), Y: float64(y)}).Mul(cellSize))
			d := s.Evaluate(pos)
			dmax = math.Max(dmax, d)
			dmin = math.Min(dmin, d)
		}
	}
	return
}

var defaultFont = inconsolata.Regular8x16 // Just a simple embedded font (to avoid problems with some platforms)

func drawDefaultTextWithShadow(screen *ebiten.Image, msg string, x, y int, c color.Color) {
	if runtime.GOOS != "js" { // Rendering text is slow on JS
		for dx := -1; dx <= 1; dx++ {
			for dy := -1; dy <= 1; dy++ {
				text.Draw(screen, msg, defaultFont, x+dx, y+dy, color.RGBA{R: 0, G: 0, B: 0, A: 50}) // Shadow first (background)
			}
		}
	}
	text.Draw(screen, msg, defaultFont, x, y, c)
}

func toBox2(box3 sdf.Box3) sdf.Box2 {
	return sdf.Box2{
		Min: v2.Vec{X: box3.Min.X, Y: box3.Min.Y},
		Max: v2.Vec{X: box3.Max.X, Y: box3.Max.Y},
	}
}