Added camera orbit controls.

src/display/camera.c

@@ -35,4 +35,15 @@ void cameraOrtho(camera_t *camera,
 ) {
   matrixIdentity(&camera->projection);
   matrixOrtho(&camera->projection, left, right, bottom, top, camNear, camFar);
+}
+
+void cameraOrbit(camera_t *camera,
+  float distance, float yaw, float pitch,
+  float targetX, float targetY, float targetZ
+) {
+  float cy = cos(pitch);
+  float x = distance * sin(yaw) * cy;
+  float y = distance * sin(pitch);
+  float z = distance * cos(yaw) * cy;
+  cameraLookAt(camera, x, y, z, targetX, targetY, targetZ);
 }