From 2a7d141ddb46bb1ef5dd5d1bb9f82152807ad650 Mon Sep 17 00:00:00 2001
From: Meghan Denny <hello@nektro.net>
Date: Thu, 14 Sep 2023 20:23:22 -0700
Subject: [PATCH] add HSV

---
 HSV.zig  | 26 ++++++++++++++++++++++++++
 mod.zig  |  1 +
 sRGB.zig | 18 ++++++++++++++++++
 3 files changed, 45 insertions(+)
 create mode 100644 HSV.zig

diff --git a/HSV.zig b/HSV.zig
new file mode 100644
index 0000000000000000000000000000000000000000..7db51d0da3c2cf12a5f161c6b1f087071598508c
--- /dev/null
+++ b/HSV.zig
@@ -0,0 +1,26 @@
+//! object representing a single color in the HSV colorspace with h channel value from 0-360 and s,v channel values from 0-1
+
+const std = @import("std");
+const Self = @This();
+
+h: f32, // hue
+s: f32, // saturation
+v: f32, // value
+a: f32, // alpha
+
+pub fn initHSVA(h: f32, s: f32, v: f32, a: f32) Self {
+    std.debug.assert(h >= 0.0 and h <= 1.0);
+    std.debug.assert(s >= 0.0 and s <= 1.0);
+    std.debug.assert(v >= 0.0 and v <= 1.0);
+    std.debug.assert(a >= 0.0 and a <= 1.0);
+    return Self{
+        .h = h,
+        .s = s,
+        .v = v,
+        .a = a,
+    };
+}
+
+pub fn eql(x: Self, y: Self) bool {
+    return x.h == y.h and x.s == y.s and x.v == y.v and x.a == y.a;
+}
diff --git a/mod.zig b/mod.zig
index 621e3dcdf45a9f1b7de0842ba0dac64e832ed6cd..a5fbd2ac934f3a91da9e5ac8c6bfc7b872a62349 100644
--- a/mod.zig
+++ b/mod.zig
@@ -5,3 +5,4 @@ pub const sRGB = @import("./sRGB.zig");
 pub const LinearRgb = @import("./LinearRgb.zig");
 pub const CMYK = @import("./CMYK.zig");
 pub const HSL = @import("./HSL.zig");
+pub const HSV = @import("./HSV.zig");
diff --git a/sRGB.zig b/sRGB.zig
index a93e9cfeab7ce6db934e8aa91b4570756a964ce1..46b42d2de25f30cd08e185cacb0ba09bce765ee2 100644
--- a/sRGB.zig
+++ b/sRGB.zig
@@ -126,3 +126,21 @@ pub fn to_hsl(x: Self) color.HSL {
     const a = f.a;
     return color.HSL.initHSLA(h, s, l, a);
 }
+
+pub fn to_hsv(x: Self) color.HSV {
+    const f = x.to_float();
+    const cmax = @max(f.r, f.g, f.b);
+    const cmin = @min(f.r, f.g, f.b);
+    const delta = cmax - cmin;
+    const h = blk: {
+        if (delta == 0) break :blk 0;
+        if (cmax == f.r) break :blk ((((f.g - f.b) / delta) % 6) * 60) % 360;
+        if (cmax == f.g) break :blk ((((f.b - f.r) / delta) + 2) * 60) % 360;
+        if (cmax == f.b) break :blk ((((f.r - f.g) / delta) + 4) * 60) % 360;
+        unreachable;
+    };
+    const s = if (cmax == 0) 0 else delta / cmax;
+    const v = cmax;
+    const a = f.a;
+    return color.HSV.initHSVA(h, s, v, a);
+}
-- 
2.54.0