fixed wrong axes

buffer.go

@@ -14,11 +14,11 @@ type Buffer struct {
 
 // NewBuffer makes a new buffer with the given dimensions
 func NewBuffer(width, height int) *Buffer {
-	b := make([][]rune, width)
+	b := make([][]rune, height)
-	for x := range b {
+	for y := range b {
-		b[x] = make([]rune, height)
+		b[y] = make([]rune, width)
-		for y := range b[x] {
+		for x := range b[y] {
-			b[x][y] = ' '
+			b[y][x] = ' '
 		}
 	}
 
@@ -31,11 +31,11 @@ func NewBuffer(width, height int) *Buffer {
 }
 
 func (b *Buffer) Set(x, y int, c rune) {
-	b.data[x][y] = c
+	b.data[y][x] = c
 }
 
 func (b *Buffer) Get(x, y int) rune {
-	return b.data[x][y]
+	return b.data[y][x]
 }
 
 func (b *Buffer) Size() (w, h int) {
@@ -52,8 +52,8 @@ func (b *Buffer) Height() int {
 
 // Draw calls drawFunc for every rune in this buffer
 func (b *Buffer) Draw(drawFunc func(x, y int, c rune)) {
-	for x, row := range b.data {
+	for y, col := range b.data {
-		for y, char := range row {
+		for x, char := range col {
 			drawFunc(x, y, char)
 		}
 	}
@@ -61,11 +61,11 @@ func (b *Buffer) Draw(drawFunc func(x, y int, c rune)) {
 
 func (b *Buffer) String() string {
 	s := new(strings.Builder)
-	for ri, row := range b.data {
+	for ci, col := range b.data {
-		for _, char := range row {
+		for _, char := range col {
 			s.WriteRune(char)
 		}
-		if ri != len(b.data)-1 {
+		if ci != len(b.data)-1 {
 			s.WriteRune('\n')
 		}
 	}
@@ -84,10 +84,10 @@ func (b *Buffer) Sub(x, y, w, h int) *Buffer {
 	h = limit(h, 1, b.height-y)
 
 	// make slice references
-	data := make([][]rune, w)
+	data := make([][]rune, h)
-	for dx := x; dx < x+w-1; dx++ {
+	for dy := y; dy < y+h-1; dy++ {
-		row := b.data[dx]
+		col := b.data[dy]
-		data[dx] = row[y : y+w]
+		data[dy] = col[x : x+w]
 	}
 
 	// make buffer

buffer_sub_test.go

@@ -2,15 +2,17 @@ package buf2d
 
 import (
 	"fmt"
+	"strings"
 	"testing"
 )
 
 func TestSub(t *testing.T) {
 	b := NewBuffer(10, 10)
 	s := b.Sub(1, 1, b.Width()-1, b.Height()-1)
-	b.Set(5, 5, 'a')
+	b.Set(5, 1, 'a')
 	s.Set(5, 5, 'b')
 
 	fmt.Println(b)
+	fmt.Println(strings.Repeat("-", 20))
 	fmt.Println(s)
 }