allg5/alui/control.go

package alui

import (
	"opslag.de/schobers/allg5"
	"opslag.de/schobers/geom"
)

type Control interface {
	Bounds() geom.RectangleF32

	Handle(*Context, allg5.Event)

	DesiredSize(*Context) geom.PointF32
	Layout(*Context, geom.RectangleF32)
	Render(*Context, geom.RectangleF32)
}

type Bounds struct {
	value geom.RectangleF32
}

var _ Control = &ControlBase{}

type ControlBase struct {
	_Bounds    geom.RectangleF32
	Over       bool
	Font       string
	Foreground *allg5.Color
	Background *allg5.Color

	OnClick func(*Context)
	OnEnter func(*Context)
	OnLeave func(*Context)
}

func MouseEventToPos(e allg5.MouseEvent) geom.PointF32 { return geom.PtF32(float32(e.X), float32(e.Y)) }

func (b *ControlBase) DesiredSize(*Context) geom.PointF32 { return geom.ZeroPtF32 }

func (b *ControlBase) Handle(ctx *Context, e allg5.Event) {
	switch e := e.(type) {
	case *allg5.MouseMoveEvent:
		pos := MouseEventToPos(e.MouseEvent)
		over := pos.In(b._Bounds)
		if over != b.Over {
			b.Over = over
			if over {
				if b.OnEnter != nil {
					b.OnEnter(ctx)
				}
			} else {
				if b.OnLeave != nil {
					b.OnLeave(ctx)
				}
			}
		}
	case *allg5.MouseButtonDownEvent:
		if !b.Over {
			break
		}
		if e.Button == allg5.MouseButtonLeft {
			if b.OnClick != nil {
				b.OnClick(ctx)
			}
		}
	}
}

func (b *ControlBase) Layout(_ *Context, bounds geom.RectangleF32) { b._Bounds = bounds }

func (b *ControlBase) Render(*Context, geom.RectangleF32) {}

func (b *ControlBase) Bounds() geom.RectangleF32 { return b._Bounds }