[API] Add ImColor#hslToColor methods

imgui-binding/src/main/java/imgui/ImColor.java

@@ -45,4 +45,65 @@ public final class ImColor {
             Integer.parseInt(hex.substring(7, 9), 16)
         );
     }
+
+    public static int hslToColor(final int h, final int s, final int l) {
+        return hslToColor(h, s, l, 1);
+    }
+
+    public static int hslToColor(final int h, final int s, final int l, final float a) {
+        return hslToColor(h / 360f, s / 100f, l / 100f, a);
+    }
+
+    public static int hslToColor(final float h, final float s, final float l) {
+        return hslToColor(h, s, l, 1);
+    }
+
+    public static int hslToColor(final float h, final float s, final float l, final float a) {
+        final float q;
+        final float p;
+        final float r;
+        final float g;
+        final float b;
+
+        // Achromatic
+        if (s == 0) {
+            r = l;
+            g = l;
+            b = l;
+        } else {
+            q = l < 0.5 ? (l * (1 + s)) : (l + s - l * s);
+            p = 2 * l - q;
+            r = hue2rgb(p, q, h + 1.0f / 3);
+            g = hue2rgb(p, q, h);
+            b = hue2rgb(p, q, h - 1.0f / 3);
+        }
+
+        return floatToColor(r, g, b, a);
+    }
+
+    private static float hue2rgb(final float p, final float q, final float hue) {
+        float h = hue;
+
+        if (h < 0) {
+            h += 1;
+        }
+
+        if (h > 1) {
+            h -= 1;
+        }
+
+        if (6 * h < 1) {
+            return p + ((q - p) * 6 * h);
+        }
+
+        if (2 * h < 1) {
+            return q;
+        }
+
+        if (3 * h < 2) {
+            return p + ((q - p) * 6 * ((2.0f / 3.0f) - h));
+        }
+
+        return p;
+    }
 }