Implement ability to move and rotate camera

src/raytracer/main.c

@@ -3,6 +3,7 @@
 #include "vector/vec.h"
 #include "window/window.h"
 #include <SDL2/SDL_events.h>
+#include <SDL2/SDL_keycode.h>
 #include <math.h>
 #include <stdbool.h>
 #include <stdlib.h>
@@ -10,10 +11,18 @@
 #define ARR_LEN(ARR) sizeof(ARR) / sizeof(ARR[0])
 #define RECURSION_DEPTH 3
 
+typedef struct {
+  vec3f_t position;
+  vec3f_t rotation;
+} camera_t;
+
 i32 main(i32 argc, char *argv[]) {
   colour_t bg =
       (colour_t){.rgba.r = 27, .rgba.g = 38, .rgba.b = 79, .rgba.a = 255};
-  vec3f_t camera = {.x = 0.0f, .y = 0.0f, .z = 0.0f};
+  camera_t camera = {
+      .position = {.x = 0.0f, .y = 0.0f, .z = 0.0f},
+      .rotation = {.x = 0.0f, .y = 0.0f, .z = 0.0f},
+  };
   vec3f_t viewport = {.x = 1.0f, .y = 1.0f, .z = 1.0f};
 
   window_t window = {0};
@@ -107,8 +116,9 @@ i32 main(i32 argc, char *argv[]) {
     for (i32 y = h_min; y < h_max; ++y) {
       for (i32 x = w_min; x < w_max; ++x) {
         vec3f_t direction = window_to_viewport(&window, x, y, viewport);
-        colour_t colour = trace_ray(camera, direction, 1, INFINITY, &scene, bg,
-                                    RECURSION_DEPTH);
+        vec3f_t rotated = vec_rotate_vec3f_t(direction, camera.rotation);
+        colour_t colour = trace_ray(camera.position, rotated, 1, INFINITY,
+                                    &scene, bg, RECURSION_DEPTH);
         set_pixel(&window, x, y, colour);
       }
     }