Add possibility to play with focal length and aperture to the camera. Not enabled by default.

source/include/camera.h

@@ -21,6 +21,10 @@ private:
     double halfWidth;
     double halfHeight;
 public:
+    double focalDistance;
+    double apertureSize;
+    uint32_t rayCount;
+
     uint32_t verticalSize;
     uint32_t horizontalSize;
     double fieldOfView;
@@ -29,9 +33,9 @@ public:
     Matrix inverseTransform;
 
 public:
-    Camera(uint32_t hsize, uint32_t vsize, double fov);
+    Camera(uint32_t hsize, uint32_t vsize, double fov, double focal = 1, double aperture = 0, uint32_t rayCount = 1);
     void setTransform(Matrix transform);
-    Ray rayForPixel(uint32_t pixelX, uint32_t pixelY);
+    Ray rayForPixel(uint32_t pixelX, uint32_t pixelY, double horzOffset = 0, double vertOffset = 0);
     Canvas render(World w, uint32_t depth = 5);
 };
 

source/include/math_helper.h

@@ -22,6 +22,7 @@ double min3(double a, double b, double c);
 double max3(double a, double b, double c);
 
 double frand();
+double frandclip(double min, double max);
 
 static double modulo(double a, double b)
 {