FollowCam cam = FollowCam(0); // TODO: Why on earth is this necessary?? Remove this and fix the error.

Entity target;

// all angles in radians

float yaw = 0;

float pitch = 0;

float sensitivity = 0.002f;

FPSCam() {

target = Entity();

target.position = HMM_Vec3(0.0f, 0.0f, -1.0f);

cam = FollowCam(&target);

AddChild(&target);

AddChild(&cam);

}

void Tick(float deltaSeconds, Input previousInput, Input input) override {

double deltaX = input.mouseX - previousInput.mouseX;

double deltaY = input.mouseY - previousInput.mouseY;

// HACK: Pitch is being weird for reasons I don't understand. It works fine for

// 360 degrees, then does something silly for 360 degrees, then repeats. I suspect

// I'm just doing something wrong with quaternions because I know they encode twice

// the angle or whatever. In any case, I've hacked around it for now to splice

// together ranges that work.

yaw = yaw + (-deltaX * sensitivity);

pitch = HMM_Clamp(-HMM_PI32 / 2, pitch + (-deltaY * sensitivity), HMM_PI32 / 2);

// HACK: MEGAHACK: why the heck is the apparent rotation twice what it should be?

float hackyPitch = HMM_PI32;

if (pitch > 0) {

hackyPitch = HMM_PI32 + pitch / 2;

} else if (pitch < 0) {

hackyPitch = 2 * HMM_PI32 + pitch / 2;

}

printf("%f\t%f\n", pitch, hackyPitch);

hmm_quaternion rotationYaw = HMM_QuaternionFromAxisAngle(HMM_Vec3(0.0f, 1.0f, 0.0f), yaw);

hmm_quaternion rotationPitch = HMM_QuaternionFromAxisAngle(HMM_Vec3(1.0f, 0.0f, 0.0f), hackyPitch);

rotation = rotationPitch * rotationYaw;

}