use cells instead of only bools, use pointer list to all neighbors

src/grid.go

@@ -12,35 +12,100 @@ import (
 	"github.com/tlinden/golsky/rle"
 )
 
+type Cell struct {
+	State         bool
+	Neighbors     [8]*Cell
+	NeighborCount int
+}
+
+func (cell *Cell) Count() int {
+	count := 0
+
+	for idx := 0; idx < cell.NeighborCount; idx++ {
+		count += bool2int(cell.Neighbors[idx].State)
+	}
+
+	return count
+}
+
 type Grid struct {
-	Data                   [][]bool
-	Width, Height, Density int
-	Empty                  bool
+	Data   [][]*Cell
+	Empty  bool
+	Config *Config
 }
 
 // Create new empty grid and allocate Data according to provided dimensions
-func NewGrid(width, height, density int, empty bool) *Grid {
+func NewGrid(config *Config) *Grid {
 	grid := &Grid{
-		Height:  height,
-		Width:   width,
-		Density: density,
-		Data:    make([][]bool, height),
-		Empty:   empty,
+		Data:   make([][]*Cell, config.Height),
+		Empty:  config.Empty,
+		Config: config,
 	}
 
-	for y := 0; y < height; y++ {
-		grid.Data[y] = make([]bool, width)
+	// first setup the cells
+	for y := 0; y < config.Height; y++ {
+		grid.Data[y] = make([]*Cell, config.Width)
+		for x := 0; x < config.Width; x++ {
+			grid.Data[y][x] = &Cell{}
+		}
+	}
+
+	// in a second pass, collect pointers to the neighbors of each cell
+	for y := 0; y < config.Height; y++ {
+		for x := 0; x < config.Width; x++ {
+			grid.SetupNeighbors(x, y)
+		}
 	}
 
 	return grid
 }
 
+func (grid *Grid) SetupNeighbors(x, y int) {
+	idx := 0
+
+	for nbgY := -1; nbgY < 2; nbgY++ {
+		for nbgX := -1; nbgX < 2; nbgX++ {
+			var col, row int
+
+			if grid.Config.Wrap {
+				// In wrap mode we look at all the 8 neighbors surrounding us.
+				// In case we are on an edge we'll look at the neighbor on the
+				//  other side  of the  grid, thus  wrapping lookahead  around
+				// using the mod() function.
+				col = (x + nbgX + grid.Config.Width) % grid.Config.Width
+				row = (y + nbgY + grid.Config.Height) % grid.Config.Height
+
+			} else {
+				// In traditional grid mode the edges are deadly
+				if x+nbgX < 0 || x+nbgX >= grid.Config.Width || y+nbgY < 0 || y+nbgY >= grid.Config.Height {
+					continue
+				}
+
+				col = x + nbgX
+				row = y + nbgY
+			}
+
+			if col == x && row == y {
+				continue
+			}
+
+			grid.Data[y][x].Neighbors[idx] = grid.Data[row][col]
+			grid.Data[y][x].NeighborCount++
+			idx++
+		}
+	}
+}
+
+// count the living neighbors of a cell
+func (grid *Grid) CountNeighbors(x, y int) int {
+	return grid.Data[y][x].Count()
+}
+
 // Create a new 1:1 instance
 func (grid *Grid) Clone() *Grid {
 	newgrid := &Grid{}
 
-	newgrid.Width = grid.Width
-	newgrid.Height = grid.Height
+	newgrid.Config = grid.Config
 	newgrid.Data = grid.Data
 
 	return newgrid
@@ -59,7 +124,7 @@ func (grid *Grid) Copy(other *Grid) {
 func (grid *Grid) Clear() {
 	for y := range grid.Data {
 		for x := range grid.Data[y] {
-			grid.Data[y][x] = false
+			grid.Data[y][x].State = false
 		}
 	}
 }
@@ -69,8 +134,8 @@ func (grid *Grid) FillRandom() {
 	if !grid.Empty {
 		for y := range grid.Data {
 			for x := range grid.Data[y] {
-				if rand.Intn(grid.Density) == 1 {
-					grid.Data[y][x] = true
+				if rand.Intn(grid.Config.Density) == 1 {
+					grid.Data[y][x].State = true
 				}
 			}
 		}
@@ -78,9 +143,9 @@ func (grid *Grid) FillRandom() {
 }
 
 func (grid *Grid) Dump() {
-	for y := 0; y < grid.Height; y++ {
-		for x := 0; x < grid.Width; x++ {
-			if grid.Data[y][x] {
+	for y := 0; y < grid.Config.Height; y++ {
+		for x := 0; x < grid.Config.Width; x++ {
+			if grid.Data[y][x].State {
 				fmt.Print("XX")
 			} else {
 				fmt.Print("  ")
@@ -93,8 +158,8 @@ func (grid *Grid) Dump() {
 // initialize using a given RLE pattern
 func (grid *Grid) LoadRLE(pattern *rle.RLE) {
 	if pattern != nil {
-		startX := (grid.Width / 2) - (pattern.Width / 2)
-		startY := (grid.Height / 2) - (pattern.Height / 2)
+		startX := (grid.Config.Width / 2) - (pattern.Width / 2)
+		startY := (grid.Config.Height / 2) - (pattern.Height / 2)
 		var y, x int
 
 		for rowIndex, patternRow := range pattern.Pattern {
@@ -103,7 +168,7 @@ func (grid *Grid) LoadRLE(pattern *rle.RLE) {
 					x = colIndex + startX
 					y = rowIndex + startY
 
-					grid.Data[y][x] = true
+					grid.Data[y][x].State = true
 				}
 			}
 		}
@@ -214,7 +279,7 @@ func (grid *Grid) SaveState(filename, rule string) error {
 	for y := range grid.Data {
 		for _, cell := range grid.Data[y] {
 			row := "."
-			if cell {
+			if cell.State {
 				row = "o"
 			}
 

src/play.go

@@ -119,14 +119,14 @@ func (scene *ScenePlay) UpdateCells() {
 	// compute life status of cells
 	for y := 0; y < scene.Config.Height; y++ {
 		for x := 0; x < scene.Config.Width; x++ {
-			state := scene.Grids[scene.Index].Data[y][x] // 0|1 == dead or alive
-			neighbors := scene.CountNeighbors(x, y)      // alive neighbor count
+			state := scene.Grids[scene.Index].Data[y][x].State // 0|1 == dead or alive
+			neighbors := scene.Grids[scene.Index].CountNeighbors(x, y)
 
 			// actually apply the current rules
 			nextstate := scene.CheckRule(state, neighbors)
 
 			// change state of current cell in next grid
-			scene.Grids[next].Data[y][x] = nextstate
+			scene.Grids[next].Data[y][x].State = nextstate
 
 			if scene.Config.ShowEvolution {
 				// set history  to current generation so we  can infer the
@@ -136,9 +136,6 @@ func (scene *ScenePlay) UpdateCells() {
 				if state != nextstate {
 					scene.History[y][x] = scene.Generations
 				}
-
-				// 10FPS:
-				//scene.History.Data[y][x] = (state ^ (1 ^ nextstate)) * (scene.Generations - scene.History.Data[y][x])
 			}
 		}
 	}
@@ -376,7 +373,7 @@ func (scene *ScenePlay) SaveRectRLE() {
 		grid[y] = make([]bool, width)
 
 		for x := 0; x < width; x++ {
-			grid[y][x] = scene.Grids[scene.Index].Data[y+starty][x+startx]
+			grid[y][x] = scene.Grids[scene.Index].Data[y+starty][x+startx].State
 		}
 	}
 
@@ -429,7 +426,7 @@ func (scene *ScenePlay) ToggleCellOnCursorPos(alive bool) {
 	y := int(worldY) / scene.Config.Cellsize
 
 	if x > -1 && y > -1 && x < scene.Config.Width && y < scene.Config.Height {
-		scene.Grids[scene.Index].Data[y][x] = alive
+		scene.Grids[scene.Index].Data[y][x].State = alive
 		scene.History[y][x] = 1
 	}
 }
@@ -455,7 +452,7 @@ func (scene *ScenePlay) Draw(screen *ebiten.Image) {
 			if scene.Config.ShowEvolution {
 				scene.DrawEvolution(screen, x, y, op)
 			} else {
-				if scene.Grids[scene.Index].Data[y][x] {
+				if scene.Grids[scene.Index].Data[y][x].State {
 					scene.World.DrawImage(scene.Theme.Tile(ColLife), op)
 				}
 			}
@@ -472,7 +469,7 @@ func (scene *ScenePlay) Draw(screen *ebiten.Image) {
 func (scene *ScenePlay) DrawEvolution(screen *ebiten.Image, x, y int, op *ebiten.DrawImageOptions) {
 	age := scene.Generations - scene.History[y][x]
 
-	switch scene.Grids[scene.Index].Data[y][x] {
+	switch scene.Grids[scene.Index].Data[y][x].State {
 	case Alive:
 		if age > 50 && scene.Config.ShowEvolution {
 			scene.World.DrawImage(scene.Theme.Tile(ColOld), op)
@@ -580,8 +577,8 @@ func (scene *ScenePlay) InitCache() {
 
 // initialize grid[s], either using pre-computed from state or rle file, or random
 func (scene *ScenePlay) InitGrid() {
-	grida := NewGrid(scene.Config.Width, scene.Config.Height, scene.Config.Density, scene.Config.Empty)
-	gridb := NewGrid(scene.Config.Width, scene.Config.Height, scene.Config.Density, scene.Config.Empty)
+	grida := NewGrid(scene.Config)
+	gridb := NewGrid(scene.Config)
 
 	// startup is delayed until user has selected options
 	grida.FillRandom()
@@ -650,39 +647,3 @@ func (scene *ScenePlay) Init() {
 func bool2int(b bool) int {
 	return int(*(*byte)(unsafe.Pointer(&b)))
 }
-
-// count the living neighbors of a cell
-func (scene *ScenePlay) CountNeighbors(x, y int) int {
-	var sum int
-
-	grid := scene.Grids[scene.Index].Data
-
-	for nbgX := -1; nbgX < 2; nbgX++ {
-		for nbgY := -1; nbgY < 2; nbgY++ {
-			var col, row int
-			if scene.Config.Wrap {
-				// In wrap mode we look at all the 8 neighbors surrounding us.
-				// In case we are on an edge we'll look at the neighbor on the
-				//  other side  of the  grid, thus  wrapping lookahead  around
-				// using the mod() function.
-				col = (x + nbgX + scene.Config.Width) % scene.Config.Width
-				row = (y + nbgY + scene.Config.Height) % scene.Config.Height
-
-			} else {
-				// In traditional grid mode the edges are deadly
-				if x+nbgX < 0 || x+nbgX >= scene.Config.Width || y+nbgY < 0 || y+nbgY >= scene.Config.Height {
-					continue
-				}
-				col = x + nbgX
-				row = y + nbgY
-			}
-
-			sum += bool2int(grid[row][col])
-		}
-	}
-
-	// don't count ourselfes though
-	sum -= bool2int(grid[y][x])
-
-	return sum
-}