Adding support for pattern.

Still a bit more work to be done there.

source/pattern.cpp

@@ -0,0 +1,31 @@
+/*
+ *  DoRayMe - a quick and dirty Raytracer
+ *  Pattern implementation
+ *
+ *  Created by Manoël Trapier
+ *  Copyright (c) 2020 986-Studio.
+ *
+ */
+
+#include <pattern.h>
+#include <shape.h>
+
+Pattern::Pattern(Colour a, Colour b): a(a), b(b)
+{
+    this->transformMatrix = Matrix4().identity();
+    this->inverseTransform = this->transformMatrix.inverse();
+};
+
+Colour Pattern::patternAtObject(Shape *object, Tuple worldPoint)
+{
+    Tuple objectPoint = object->inverseTransform * worldPoint;
+    Tuple patternPoint = this->inverseTransform * objectPoint;
+
+    return this->patternAt(patternPoint);
+}
+
+void Pattern::setTransform(Matrix transform)
+{
+    this->transformMatrix = transform;
+    this->inverseTransform = transform.inverse();
+}