1 files changed, 57 insertions, 0 deletions
diff --git a/autoutils/colorconversion.go b/autoutils/colorconversion.go
new file mode 100644
index 0000000..af21668
--- /dev/null
+++ b/autoutils/colorconversion.go
@@ -0,0 +1,57 @@
+/*
+Copyright (C) 2019 Leo Tenenbaum
+
+This file is part of AutoArt.
+
+AutoArt is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+AutoArt is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with AutoArt.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+package autoutils
+import (
+    "math"
+)
+
+func HSVToRGB(h uint8, s uint8, v uint8) (uint8, uint8, uint8) {
+    // https://en.wikipedia.org/wiki/HSL_and_HSV#HSV_to_RGB
+    V := float64(v) / 256
+    S := float64(s) / 256
+    C := V * S
+    H := float64(h) / (256/6)
+    X := float64(C) * (1 - math.Abs(math.Mod(H, 2) - 1))
+    var r, g, b float64
+    switch true {
+    case s == 0:
+        r, g, b = 0, 0, 0
+    case H <= 1:
+        r, g, b = C, X, 0
+    case H <= 2:
+        r, g, b = X, C, 0
+    case H <= 3:
+        r, g, b = 0, C, X
+    case H <= 4:
+        r, g, b = 0, X, C
+    case H <= 5:
+        r, g, b = X, 0, C
+    default:
+        r, g, b = C, 0, X
+    }
+    m := V - C
+    r += m
+    g += m
+    b += m
+    r *= 255
+    g *= 255
+    b *= 255
+    return uint8(r), uint8(g), uint8(b)
+}