refactor: generator

pkg/generator/plotter.go

@@ -0,0 +1,60 @@
+package generator
+
+import (
+	"errors"
+	"fmt"
+	"math/rand"
+
+	"github.com/iliadenisov/galaxy/pkg/bitmap"
+)
+
+type Plotter struct {
+	factor              float32
+	clearFn             func()
+	circleFn            func(x, y int, r float32)
+	freeCountFn         func() int
+	freeNumberToCoordFn func(int) (int, int)
+}
+
+func NewPlotter(width, height uint, factor float32) (Plotter, error) {
+	if factor > 1 || factor <= 0 {
+		return Plotter{}, fmt.Errorf("factor should be: 0 > F <= 1")
+	}
+	sectorsX := uint32(float32(width) / factor)
+	sectorsY := uint32(float32(height) / factor)
+	bm := bitmap.NewBitmap(sectorsX, sectorsY)
+	return Plotter{
+		factor:      factor,
+		clearFn:     bm.Clear,
+		circleFn:    func(x, y int, r float32) { bm.Circle(x, y, r, true) },
+		freeCountFn: bm.FreeCount,
+		freeNumberToCoordFn: func(n int) (x int, y int) {
+			x, y, err := bm.GetFreeN(n)
+			if err != nil {
+				panic(err)
+			}
+			return
+		},
+	}, nil
+}
+
+func (p Plotter) RandomFreePoint(deadZoneRaduis float32) (float32, float32, error) {
+	fsCount := p.freeCountFn()
+	if fsCount == 0 {
+		return 0, 0, errors.New("no more space for planets")
+	}
+	next := rand.Intn(fsCount)
+	x, y := p.freeNumberToCoordFn(next)
+	p.PlotDeadZone(x, y, deadZoneRaduis)
+	planetX := float32(x)*p.factor + rand.Float32()*p.factor // TODO: correct shift?
+	planetY := float32(y)*p.factor + rand.Float32()*p.factor
+	return planetX, planetY, nil
+}
+
+func (p Plotter) MarkDeadZone(x, y float32, radius float32) {
+	p.PlotDeadZone(int(x/p.factor), int(y/p.factor), radius)
+}
+
+func (p Plotter) PlotDeadZone(x, y int, radius float32) {
+	p.circleFn(x, y, radius/p.factor)
+}