From 4e58fd02a738634e26219414d755f5ae909049ee Mon Sep 17 00:00:00 2001
From: Mirko Janssen <mail@mirkojanssen.de>
Date: Sat, 21 Sep 2019 21:00:28 +0200
Subject: [PATCH] implemented Color

---
 src/Primitives/Color.php       | 114 +++++++++++++++++++++++++++++++++
 tests/Primitives/ColorTest.php | 112 ++++++++++++++++++++++++++++++++
 2 files changed, 226 insertions(+)
 create mode 100644 src/Primitives/Color.php
 create mode 100644 tests/Primitives/ColorTest.php

diff --git a/src/Primitives/Color.php b/src/Primitives/Color.php
new file mode 100644
index 0000000..c88fb85
--- /dev/null
+++ b/src/Primitives/Color.php
@@ -0,0 +1,114 @@
+<?php
+
+declare(strict_types=1);
+
+namespace ItsAMirko\RayTracer\Primitives;
+
+/**
+ * Class Color
+ *
+ * @package ItsAMirko\RayTracer\Primitives
+ */
+class Color
+{
+    /**
+     * @var float
+     */
+    private $red;
+    
+    /**
+     * @var float
+     */
+    private $green;
+    
+    /**
+     * @var float
+     */
+    private $blue;
+    
+    
+    /**
+     * Color constructor.
+     *
+     * @param float $red
+     * @param float $green
+     * @param float $blue
+     */
+    public function __construct(float $red, float $green, float $blue)
+    {
+        $this->red   = $red;
+        $this->green = $green;
+        $this->blue  = $blue;
+    }
+    
+    
+    /**
+     * @return float
+     */
+    public function red(): float
+    {
+        return $this->red;
+    }
+    
+    
+    /**
+     * @return float
+     */
+    public function green(): float
+    {
+        return $this->green;
+    }
+    
+    
+    /**
+     * @return float
+     */
+    public function blue(): float
+    {
+        return $this->blue;
+    }
+    
+    
+    /**
+     * @param Color $color
+     *
+     * @return Color
+     */
+    public function plusColor(Color $color): Color
+    {
+        return new Color($this->red + $color->red(), $this->green + $color->green(), $this->blue + $color->blue());
+    }
+    
+    
+    /**
+     * @param Color $color
+     *
+     * @return Color
+     */
+    public function minusColor(Color $color): Color
+    {
+        return new Color($this->red - $color->red(), $this->green - $color->green(), $this->blue - $color->blue());
+    }
+    
+    
+    /**
+     * @param float $multiplier
+     *
+     * @return Color
+     */
+    public function multiplyWithScalar(float $multiplier): Color
+    {
+        return new Color($this->red * $multiplier, $this->green * $multiplier, $this->blue * $multiplier);
+    }
+    
+    
+    /**
+     * @param Color $color
+     *
+     * @return Color
+     */
+    public function multiplyWithColor(Color $color): Color
+    {
+        return new Color($this->red * $color->red(), $this->green * $color->green(), $this->blue * $color->blue());
+    }
+}
\ No newline at end of file
diff --git a/tests/Primitives/ColorTest.php b/tests/Primitives/ColorTest.php
new file mode 100644
index 0000000..ff70a4b
--- /dev/null
+++ b/tests/Primitives/ColorTest.php
@@ -0,0 +1,112 @@
+<?php
+
+declare(strict_types=1);
+
+namespace ItsAMirko\RayTracer\Primitives;
+
+use Exception;
+use PHPUnit\Framework\TestCase;
+use function random_int;
+
+class ColorTest extends TestCase
+{
+    /**
+     * @var float
+     */
+    private $red;
+    
+    /**
+     * @var float
+     */
+    private $green;
+    
+    /**
+     * @var float
+     */
+    private $blue;
+    
+    
+    /**
+     * @throws Exception
+     */
+    protected function setUp(): void
+    {
+        parent::setUp();
+        
+        $this->red   = random_int(0, 100) / 100;
+        $this->green = random_int(0, 100) / 100;
+        $this->blue  = random_int(0, 100) / 100;
+    }
+    
+    
+    public function testProvidedColorValues(): void
+    {
+        $color = new Color($this->red, $this->green, $this->blue);
+        
+        $this->assertSame($this->red, $color->red());
+        $this->assertSame($this->green, $color->green());
+        $this->assertSame($this->blue, $color->blue());
+    }
+    
+    
+    public function testCreatesNewColorByAddingAColor(): void
+    {
+        $color1 = new Color(1.0, 2.0, 3.0);
+        $color2 = new Color($this->red, $this->green, $this->blue);
+        
+        $actualColor = $color1->plusColor($color2);
+        
+        $this->assertInstanceOf(Color::class, $actualColor);
+        $this->assertSame(1 + $this->red, $actualColor->red());
+        $this->assertSame(2 + $this->green, $actualColor->green());
+        $this->assertSame(3 + $this->blue, $actualColor->blue());
+    }
+    
+    
+    public function testCreatesNewColorBySubtractingAColor(): void
+    {
+        $color1 = new Color(1.0, 2.0, 3.0);
+        $color2 = new Color($this->red, $this->green, $this->blue);
+        
+        $actualColor = $color1->minusColor($color2);
+        
+        $this->assertInstanceOf(Color::class, $actualColor);
+        $this->assertSame(1 - $this->red, $actualColor->red());
+        $this->assertSame(2 - $this->green, $actualColor->green());
+        $this->assertSame(3 - $this->blue, $actualColor->blue());
+    }
+    
+    
+    /**
+     * @throws Exception
+     */
+    public function testCreatesNewColorByMultiplyingWithAScalar(): void
+    {
+        $color  = new Color($this->red, $this->green, $this->blue);
+        $scalar = random_int(0, 100) / 100;
+        
+        $actualColor = $color->multiplyWithScalar($scalar);
+        
+        $this->assertInstanceOf(Color::class, $actualColor);
+        $this->assertSame($scalar * $this->red, $actualColor->red());
+        $this->assertSame($scalar * $this->green, $actualColor->green());
+        $this->assertSame($scalar * $this->blue, $actualColor->blue());
+    }
+    
+    
+    /**
+     * @throws Exception
+     */
+    public function testCreatesNewColorByMultiplyingWithAColor(): void
+    {
+        $color1 = new Color(1.0, 2.0, 3.0);
+        $color2 = new Color($this->red, $this->green, $this->blue);
+        
+        $actualColor = $color1->multiplyWithColor($color2);
+        
+        $this->assertInstanceOf(Color::class, $actualColor);
+        $this->assertSame(1.0 * $this->red, $actualColor->red());
+        $this->assertSame(2.0 * $this->green, $actualColor->green());
+        $this->assertSame(3.0 * $this->blue, $actualColor->blue());
+    }
+}