completed refactoring to use systems

grid/grid.go

@@ -0,0 +1,115 @@
+package grid
+
+import (
+	"fmt"
+	"image"
+	"log"
+	"openquell/assets"
+	"openquell/components"
+
+	"github.com/mlange-42/arche/ecs"
+	"github.com/mlange-42/arche/generic"
+)
+
+type Grid struct {
+	Width    int
+	Height   int
+	Size     int
+	Tilesize int
+	Map      map[image.Point]*assets.Tile
+}
+
+// FIXME: put component addition into extra callable function, to be called
+// by game.go in a level-loop. Also remove components of previous level
+func NewGrid(world *ecs.World,
+	tilesize, width, height int, mapslice map[image.Point]*assets.Tile) *Grid {
+
+	// we use this to turn  our tiles into iterable entities, used for
+	// collision detection, transformation and other things
+	playermapper := generic.NewMap4[
+		components.Position,
+		components.Velocity,
+		components.Renderable,
+		components.Player](world)
+
+	solidmapper := generic.NewMap4[
+		components.Position,
+		components.Renderable,
+		components.Tilish,
+		components.Solid](world)
+
+	emptymapper := generic.NewMap2[components.Position, components.Tilish](world)
+
+	colmapper := generic.NewMap3[
+		components.Position,
+		components.Renderable,
+		components.Collectible](world)
+
+	ptmapper := generic.NewMap2[
+		components.Position,
+		components.Particle,
+	](world)
+
+	var pos *components.Position
+	var render *components.Renderable
+
+	for point, tile := range mapslice {
+		switch tile.Renderable {
+		case true:
+			switch {
+			case tile.Solid:
+				entity := solidmapper.New()
+				pos, render, _, _ = solidmapper.Get(entity)
+			case tile.Player:
+				entity := playermapper.New()
+				pos, _, render, _ = playermapper.Get(entity)
+				fmt.Printf("player start pos: %d,%d\n", point.X*tilesize, point.Y*tilesize)
+			case tile.Collectible:
+				entity := colmapper.New()
+				pos, render, _ = colmapper.Get(entity)
+			default:
+				log.Fatalln("unsupported tile type encountered")
+			}
+
+			render.Image = tile.Sprite
+
+		default:
+			// empty  cell, this is  where the player[s]  move. No
+			// sprite required since  every level has a background
+			// image.
+			entity := emptymapper.New()
+			pos, _ = emptymapper.Get(entity)
+		}
+
+		// however, every tile has a position
+		pos.Update(point.X*tilesize, point.Y*tilesize, tilesize)
+	}
+
+	// not part of the grid, but add them as well
+	entity := ptmapper.New()
+	_, particle := ptmapper.Get(entity)
+	particle.Index = assets.Tiles['*'].Particle
+	particle.Particles = assets.Tiles['*'].Particles
+
+	return &Grid{
+		Size:     len(mapslice),
+		Tilesize: tilesize,
+		Width:    width,
+		Height:   height,
+		Map:      mapslice,
+	}
+}
+
+// return the tile the moving object would end up on if indeed moving
+func (grid *Grid) GetTile(
+	position *components.Position,
+	velocity *components.Velocity) *assets.Tile {
+
+	newpoint := image.Point{
+		int(position.X+velocity.Data.X) / grid.Tilesize,
+		int(position.Y+velocity.Data.Y) / grid.Tilesize,
+	}
+
+	tile := grid.Map[newpoint]
+	return tile
+}