114 lines
2.7 KiB
Go
114 lines
2.7 KiB
Go
package engine
|
|
|
|
import (
|
|
"image"
|
|
|
|
"drjosh.dev/gurgle/geom"
|
|
"github.com/hajimehoshi/ebiten/v2"
|
|
)
|
|
|
|
var (
|
|
_ interface {
|
|
Collider
|
|
Identifier
|
|
Scanner
|
|
Prepper
|
|
Transformer
|
|
} = &Wall{}
|
|
|
|
_ interface {
|
|
Drawer
|
|
Disabler
|
|
Hider
|
|
Scanner
|
|
Transformer
|
|
} = &WallUnit{}
|
|
)
|
|
|
|
// Wall is a more flexible kind of tilemap. WallUnits can be added at the same
|
|
// level as other components and are responsible for their own drawing, so that
|
|
// Game can do draw ordering, e.g. hide the player character behind a wall.
|
|
// But Wall is still responsible for collisions.
|
|
type Wall struct {
|
|
ID
|
|
Ersatz bool // disables collisions ("fake wall")
|
|
Offset image.Point // offset the whole wall
|
|
Sheet Sheet
|
|
UnitOffset image.Point // drawing offset
|
|
UnitSize image.Point // tile size
|
|
Units map[image.Point]*WallUnit
|
|
}
|
|
|
|
// CollidesWith implements a tilerange collosion check, similar to Tilemap.
|
|
func (w *Wall) CollidesWith(b geom.Box) bool {
|
|
if w.Ersatz {
|
|
return false
|
|
}
|
|
|
|
// Probe the map at all tilespace coordinates overlapping the rect.
|
|
r := b.XY().Sub(w.Offset)
|
|
min := geom.CDiv(r.Min, w.UnitSize)
|
|
max := geom.CDiv(r.Max.Sub(image.Pt(1, 1)), w.UnitSize) // NB: fencepost
|
|
|
|
for j := min.Y; j <= max.Y; j++ {
|
|
for i := min.X; i <= max.X; i++ {
|
|
if w.Units[image.Pt(i, j)] != nil {
|
|
return true
|
|
}
|
|
}
|
|
}
|
|
return false
|
|
}
|
|
|
|
// Scan returns the Sheet and all WallUnits.
|
|
func (w *Wall) Scan() []interface{} {
|
|
c := make([]interface{}, 1, len(w.Units)+1)
|
|
c[0] = &w.Sheet
|
|
for _, unit := range w.Units {
|
|
c = append(c, unit)
|
|
}
|
|
return c
|
|
}
|
|
|
|
// Prepare makes sure all WallUnits know about Wall and where they are, for
|
|
// drawing.
|
|
func (w *Wall) Prepare(*Game) error {
|
|
// Ensure all child units know about wall, which houses common attributes
|
|
for p, u := range w.Units {
|
|
u.pos, u.wall = p, w
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Transform returns a GeoM translation by Offset.
|
|
func (w *Wall) Transform() (opts ebiten.DrawImageOptions) {
|
|
opts.GeoM.Translate(geom.CFloat(w.Offset))
|
|
return opts
|
|
}
|
|
|
|
// WallUnit is a unit in a wall. Unlike a tile in a tilemap, WallUnit is
|
|
// responsible for drawing itself.
|
|
type WallUnit struct {
|
|
Disabled
|
|
Hidden
|
|
Tile Tile // chooses which cell in wall.Sheet to draw
|
|
ZOrder
|
|
|
|
pos image.Point // tilespace coordinates
|
|
wall *Wall
|
|
}
|
|
|
|
// Draw draws this wall unit.
|
|
func (u *WallUnit) Draw(screen *ebiten.Image, opts *ebiten.DrawImageOptions) {
|
|
screen.DrawImage(u.wall.Sheet.SubImage(u.Tile.Cell()), opts)
|
|
}
|
|
|
|
// Scan returns the Tile.
|
|
func (u *WallUnit) Scan() []interface{} { return []interface{}{u.Tile} }
|
|
|
|
func (u *WallUnit) Transform() (opts ebiten.DrawImageOptions) {
|
|
opts.GeoM.Translate(geom.CFloat(
|
|
geom.CMul(u.pos, u.wall.UnitSize).Add(u.wall.UnitOffset),
|
|
))
|
|
return opts
|
|
}
|