[orx-color] Add HPLuv and two demos

orx-color/src/commonMain/kotlin/palettes/Classics.kt

@@ -8,6 +8,8 @@ import org.openrndr.extra.color.tools.shiftHue
 /**
  * Generate an analogous palette
  * @param T the color model to use
+ * @param hueShift Hue degrees between the first and the last color
+ * @param steps Number of colors to create
  */
 inline fun <reified T> ColorRGBa.analogous(hueShift: Double, steps: Int = 5): List<ColorRGBa>
         where T : HueShiftableColor<T>,

orx-color/src/commonMain/kotlin/spaces/TypeAliases.kt

@@ -5,6 +5,7 @@ import org.openrndr.color.*
 typealias RGB = ColorRGBa
 typealias LAB = ColorLABa
 typealias LUV = ColorLUVa
+typealias HPLuv = ColorHPLUVa
 typealias HSL = ColorHSLa
 typealias HSV = ColorHSVa
 typealias HSLuv = ColorHSLUVa

orx-color/src/commonMain/kotlin/tools/ColorRGBaExtensions.kt

@@ -18,6 +18,7 @@ inline fun <reified T : ColorModel<T>> ColorRGBa.convertTo(): T {
         ColorHSLa::class -> this.toHSLa()
         ColorHSVa::class -> this.toHSVa()
         ColorRGBa::class -> this
+        ColorHPLUVa::class -> this.toHPLUVa()
         ColorHSLUVa::class -> this.toHSLUVa()
         ColorOKLABa::class -> this.toOKLABa()
         ColorOKLCHa::class -> this.toOKLCHa()

orx-color/src/jvmDemo/kotlin/DemoColorPalette01.kt

@@ -0,0 +1,60 @@
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.color.palettes.analogous
+import org.openrndr.extra.color.palettes.splitComplementary
+import org.openrndr.extra.color.palettes.tetradic
+import org.openrndr.extra.color.palettes.triadic
+import org.openrndr.extra.color.presets.ORANGE
+import org.openrndr.extra.color.spaces.*
+
+/**
+ * Demonstrates the creation of color palettes using various available methods
+ */
+fun main() = application {
+    configure { }
+    program {
+        // HueShiftableColor:
+        // HPLuv HSL HSV LCHab LCHuv XSL XSV XSLuv HSLuv OKHSL OKHSV OKLCH
+        val palette0 = RGB.PINK.analogous<HSLuv>(360.0, 10)
+        val palette1 = RGB.RED.analogous<HSL>(240.0, 3)
+        val palette2 = RGB.YELLOW.triadic<OKHSV>()
+        val palette3 = RGB.CYAN.tetradic<OKLCH>()
+        val palette4 = RGB.CYAN.tetradic<OKLCH>(0.5)
+        val palette5 = RGB.ORANGE.splitComplementary<HPLuv>(0.2, true)
+        extend {
+            drawer.clear(ColorRGBa.WHITE)
+            drawer.stroke = ColorRGBa.BLACK.opacify(0.25)
+
+            palette0.forEachIndexed { i, c ->
+                drawer.fill = c
+                drawer.circle(100.0 + i * 40.0, 80.0, 40.0)
+            }
+
+            palette1.forEachIndexed { i, c ->
+                drawer.fill = c
+                drawer.circle(100.0 + i * 40.0, 180.0, 40.0)
+            }
+
+            palette2.forEachIndexed { i, c ->
+                drawer.fill = c
+                drawer.circle(380.0 + i * 40.0, 180.0, 40.0)
+            }
+
+            palette3.forEachIndexed { i, c ->
+                drawer.fill = c
+                drawer.circle(100.0 + i * 40.0, 280.0, 40.0)
+            }
+
+            palette4.forEachIndexed { i, c ->
+                drawer.fill = c
+                drawer.circle(350.0 + i * 40.0, 280.0, 40.0)
+            }
+
+            palette5.forEachIndexed { i, c ->
+                drawer.fill = c
+                drawer.circle(100.0 + i * 40.0, 380.0, 40.0)
+            }
+
+        }
+    }
+}

orx-color/src/jvmDemo/kotlin/DemoColorPalette02.kt

@@ -0,0 +1,31 @@
+import org.openrndr.application
+import org.openrndr.extra.color.palettes.analogous
+import org.openrndr.extra.color.spaces.HSLuv
+import org.openrndr.extra.color.spaces.RGB
+
+/**
+ * By default, generated palettes contain colors of varying hue
+ * but similar brightness and saturation.
+ * Here we alter the brightness of each color using .shade() for
+ * an increased dynamic range.
+ */
+fun main() = application {
+    program {
+        val count = 8
+        val palette = RGB.PINK.analogous<HSLuv>(360.0, count).mapIndexed { i, c ->
+            c.shade((i + 1.0) / count)
+        }.reversed()
+        extend {
+            drawer.stroke = null
+
+            palette.forEachIndexed { i, c ->
+                drawer.fill = c
+                drawer.rectangle(
+                    0.0, i * height / count.toDouble(),
+                    width.toDouble(), height / count.toDouble()
+                )
+            }
+
+        }
+    }
+}