1 files changed, 88 insertions, 0 deletions
diff --git a/v_windows/v/vlib/term/ui/color.v b/v_windows/v/vlib/term/ui/color.v
new file mode 100644
index 0000000..3e0a0bb
--- /dev/null
+++ b/v_windows/v/vlib/term/ui/color.v
@@ -0,0 +1,88 @@
+// radare - LGPL - Copyright 2013-2020 - pancake, xarkes
+// ansi 256 color extension for r_cons
+// https://en.wikipedia.org/wiki/ANSI_color
+
+module ui
+
+const (
+	value_range = [0x00, 0x5f, 0x87, 0xaf, 0xd7, 0xff]!
+	color_table = init_color_table()
+)
+
+[direct_array_access]
+fn init_color_table() []int {
+	mut color_table_ := []int{len: 256}
+	// ansi colors
+	color_table_[0] = 0x000000
+	color_table_[1] = 0x800000
+	color_table_[2] = 0x008000
+	color_table_[3] = 0x808000
+	color_table_[4] = 0x000080
+	color_table_[5] = 0x800080
+	color_table_[6] = 0x008080
+	color_table_[7] = 0xc0c0c0
+	color_table_[8] = 0x808080
+	color_table_[9] = 0xff0000
+	color_table_[10] = 0x00ff00
+	color_table_[11] = 0xffff00
+	color_table_[12] = 0x0000ff
+	color_table_[13] = 0xff00ff
+	color_table_[14] = 0x00ffff
+	color_table_[15] = 0xffffff
+	// color palette
+	for i in 0 .. 216 {
+		r := ui.value_range[(i / 36) % 6]
+		g := ui.value_range[(i / 6) % 6]
+		b := ui.value_range[i % 6]
+		color_table_[i + 16] = ((r << 16) & 0xffffff) + ((g << 8) & 0xffff) + (b & 0xff)
+	}
+	// grayscale
+	for i in 0 .. 24 {
+		r := 8 + (i * 10)
+		color_table_[i + 232] = ((r << 16) & 0xffffff) + ((r << 8) & 0xffff) + (r & 0xff)
+	}
+	return color_table_
+}
+
+fn clamp(x int, y int, z int) int {
+	if x < y {
+		return y
+	}
+	if x > z {
+		return z
+	}
+	return x
+}
+
+fn approximate_rgb(r int, g int, b int) int {
+	grey := r > 0 && r < 255 && r == g && r == b
+	if grey {
+		return 232 + int(f64(r) / (255 / 24.1))
+	}
+	k := int(256.0 / 6)
+	r2 := clamp(r / k, 0, 5)
+	g2 := clamp(g / k, 0, 5)
+	b2 := clamp(b / k, 0, 5)
+	return 16 + (r2 * 36) + (g2 * 6) + b2
+}
+
+fn lookup_rgb(r int, g int, b int) int {
+	color := (r << 16) + (g << 8) + b
+	// lookup extended colors only, coz non-extended can be changed by users.
+	for i in 16 .. 256 {
+		if ui.color_table[i] == color {
+			return i
+		}
+	}
+	return -1
+}
+
+// converts an RGB color to an ANSI 256-color, approximating it to the nearest available color
+// if an exact match is not found
+fn rgb2ansi(r int, g int, b int) int {
+	c := lookup_rgb(r, g, b)
+	if c == -1 {
+		return approximate_rgb(r, g, b)
+	}
+	return c
+}