Files
ghostland-game/ghost.cpp
2025-08-03 11:15:54 -04:00

126 lines
3.1 KiB
C++

#include <GLFW/glfw3.h>
#include <glm/gtc/matrix_transform.hpp>
#include <stdio.h>
#include "ghost.h"
float pi = glm::pi<float>();
int counter = 0;
float direction_persist_factor = 0.02;
Ghost::Ghost(float xmin, float xmax, float zmin, float zmax) {
ghost_id = counter;
counter++;
this->xmin = xmin;
this->xmax = xmax;
this->zmin = zmin;
this->zmax = zmax;
pos.x = rand_float(xmin, xmax);
pos.y = 2.5;
pos.z = rand_float(zmin, zmax);
y_offset = rand_float(0.0, pi);
yawr = rand_float(0.0, pi*2.0f);
first_frame = false;
direction_persist = 0.0f;
}
void Ghost::apply_movement(float curr_time, float timed) {
// vertical movement
pos.y = 2.5 + sin(curr_time + y_offset);
moved.x = -sin(yawr) + cos(yawr);
moved.z = cos(yawr) + sin(yawr);
pos += moved * timed;
bool reset_yaw = false;
if (pos.x < xmin) {
reset_yaw = true;
pos.x = xmin;
} else if (pos.x > xmax) {
reset_yaw = true;
pos.x = xmax;
}
if (pos.z < zmin) {
reset_yaw = true;
pos.z = zmin;
} else if (pos.z > zmax) {
reset_yaw = true;
pos.z = zmax;
}
// TODO make this face origin
if (reset_yaw) {
yawr = rand_float(0.0, pi * 2.0);
} else {
yawr += rand_float(-0.05, 0.05);
}
}
glm::mat4 Ghost::get_model(glm::vec3 &camera_pos) {
// initialize to identity matrix
glm::mat4 ghost_model = glm::mat4(1.0f);
// apply location
ghost_model = glm::translate(ghost_model, pos);
// apply direction
// the cross product helps us determine which direction it's going relative to player
glm::vec3 ghost_to_player = pos - camera_pos;
glm::vec3 crossed = glm::cross(ghost_to_player, moved);
//float dist2 = ghost_to_player.x * ghost_to_player.x + ghost_to_player.z * ghost_to_player.z;
float theta = atan2f(ghost_to_player.x, ghost_to_player.z);
if (crossed.y < 0.0) {
direction_persist = (1.0 - direction_persist_factor) * direction_persist - direction_persist_factor;
} else {
direction_persist = (1.0 - direction_persist_factor) * direction_persist + direction_persist_factor;
}
if (direction_persist < 0.0) {
theta += pi;
}
ghost_model = glm::rotate(ghost_model, theta, glm::vec3(0.0f, 1.0f, 0.0f));
/*
if (dist2 > 256) {
yawr = theta;
}
if (ghost_id == 0) {
printf("(%f, %f, %f)\n", pos.x, pos.y, pos.z);
printf("%f %f %f %f\n", xmin, xmax, zmin, zmax);
}
*/
return ghost_model;
}
float rand_float(float rmin, float rmax) {
float rdiff = rmax - rmin;
float res = (float)rand()/(float)RAND_MAX;
return res * rdiff + rmin;
}
glm::vec3 Ghost::get_pos() const {
return pos;
}
void Ghost::reverse_direction_from_position(glm::vec3 target_pos) {
// Calculate direction from target_pos to ghost position
glm::vec3 direction = pos - target_pos;
// Set yawr to point directly away from target_pos
yawr = atan2(direction.x, direction.z);
}
void Ghost::regenerate_position() {
pos.x = rand_float(xmin, xmax);
pos.z = rand_float(zmin, zmax);
}