1 files changed, 72 insertions, 0 deletions
diff --git a/vendor/github.com/gizak/termui/canvas.go b/vendor/github.com/gizak/termui/canvas.go
new file mode 100644
index 000000000..4173780f3
--- /dev/null
+++ b/vendor/github.com/gizak/termui/canvas.go
@@ -0,0 +1,72 @@
+// Copyright 2016 Zack Guo <gizak@icloud.com>. All rights reserved.
+// Use of this source code is governed by a MIT license that can
+// be found in the LICENSE file.
+
+package termui
+
+/*
+dots:
+   ,___,
+   |1 4|
+   |2 5|
+   |3 6|
+   |7 8|
+   `````
+*/
+
+var brailleBase = '\u2800'
+
+var brailleOftMap = [4][2]rune{
+	{'\u0001', '\u0008'},
+	{'\u0002', '\u0010'},
+	{'\u0004', '\u0020'},
+	{'\u0040', '\u0080'}}
+
+// Canvas contains drawing map: i,j -> rune
+type Canvas map[[2]int]rune
+
+// NewCanvas returns an empty Canvas
+func NewCanvas() Canvas {
+	return make(map[[2]int]rune)
+}
+
+func chOft(x, y int) rune {
+	return brailleOftMap[y%4][x%2]
+}
+
+func (c Canvas) rawCh(x, y int) rune {
+	if ch, ok := c[[2]int{x, y}]; ok {
+		return ch
+	}
+	return '\u0000' //brailleOffset
+}
+
+// return coordinate in terminal
+func chPos(x, y int) (int, int) {
+	return y / 4, x / 2
+}
+
+// Set sets a point (x,y) in the virtual coordinate
+func (c Canvas) Set(x, y int) {
+	i, j := chPos(x, y)
+	ch := c.rawCh(i, j)
+	ch |= chOft(x, y)
+	c[[2]int{i, j}] = ch
+}
+
+// Unset removes point (x,y)
+func (c Canvas) Unset(x, y int) {
+	i, j := chPos(x, y)
+	ch := c.rawCh(i, j)
+	ch &= ^chOft(x, y)
+	c[[2]int{i, j}] = ch
+}
+
+// Buffer returns un-styled points
+func (c Canvas) Buffer() Buffer {
+	buf := NewBuffer()
+	for k, v := range c {
+		buf.Set(k[0], k[1], Cell{Ch: v + brailleBase})
+	}
+	return buf
+}