Add ghosts

ghost.cpp

@@ -0,0 +1,90 @@
+#include <GLFW/glfw3.h>
+#include <glm/gtc/matrix_transform.hpp>
+#include <stdio.h>
+
+#include "ghost.h"
+
+int counter = 0;
+
+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, 3.14);
+    yawr = rand_float(0.0, 6.28);
+
+    first_frame = false;
+
+}
+
+void Ghost::apply_movement() {
+
+    float curr_time = static_cast<float>(glfwGetTime());
+
+    if (!first_frame) {
+        first_frame = true;
+        prev_move_time = curr_time;
+        return;
+    }
+
+    float diff_time = curr_time - prev_move_time;
+    prev_move_time = curr_time;
+
+    glm::vec3 moved;
+    moved.x = pos.x + (-sin(yawr) + cos(yawr)) * diff_time;
+    moved.y = 2.5 + sin(curr_time + y_offset);
+    moved.z = pos.z + (cos(yawr) + sin(yawr)) * diff_time;
+
+    bool reset_yaw = false;
+
+    if (moved.x < xmin) {
+        reset_yaw = true;
+        moved.x = xmin;
+    } else if (moved.x > xmax) {
+        reset_yaw = true;
+        moved.x = xmax;
+    }
+
+    if (moved.z < zmin) {
+        reset_yaw = true;
+        moved.z = zmin;
+    } else if (moved.z > zmax) {
+        reset_yaw = true;
+        moved.z = zmax;
+    }
+
+    if (reset_yaw) {
+        yawr = rand_float(0.0, 6.28);
+    } else {
+        yawr += rand_float(-0.3, 0.3);
+    }
+
+    pos = moved;
+
+}
+
+glm::mat4 Ghost::get_model(glm::vec3 &camera_pos) {
+
+    glm::mat4 ghost_model = glm::mat4(1.0f);
+    ghost_model = glm::translate(ghost_model, pos);
+    glm::vec3 ghost_direction = pos - camera_pos;
+    ghost_model = glm::rotate(ghost_model, atan2f(ghost_direction.x, ghost_direction.z), glm::vec3(0.0f, 1.0f, 0.0f));
+    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;
+}