Randomness and nightmode improvements (#3)

* Bug fixes and general improvements

* Fixed moving stars and moon during gameover on nightmode
* Fixed invalid obstacle gaps
* Improved random value generation in interval
+ Added `dinorunner_seed()` for variance in random values
* Updated docs

* Bump version to 1.3.2

* Bump versions in CMakefiles for up-coming release

Author: AKJ7

README.md

@@ -81,6 +81,7 @@ unsigned char dinorunner_update(struct dinorunner_s* dinorunner);
 unsigned char dinorunner_getversion(struct version_s* version);
 unsigned char dinorunner_isinverted(const struct dinorunner_s* dinorunner, unsigned char* night_mode);
 unsigned char dinorunner_isalive(const struct dinorunner_s* dinorunner, unsigned char* activation_status);
+void dinorunner_seed(unsigned short random_seed);
 void dinorunner_onkeyup(struct dinorunner_s* dinorunner);
 void dinorunner_onkeydown(struct dinorunner_s* dinorunner);
 void dinorunner_onkeynone(struct dinorunner_s* dinorunner);

demo/CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.10)
 
 project(dinorunner-demos
-    VERSION 1.3.1
+    VERSION 1.3.2
     DESCRIPTION "Running examples of the Dinorunner libray"
     LANGUAGES C CXX)
 

demo/sdl/demo.c

@@ -15,6 +15,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <time.h>
 #include "dinorunner.h"
 
 #define LOG(format, ...) fprintf(stderr, "[%24s(%3d)] " format "\n", __FUNCTION__, __LINE__, __VA_ARGS__)
@@ -122,9 +123,6 @@ static uint8_t render_background(hypervisor_s* hypervisor) {
   int status;
   status = SDL_RenderClear(hypervisor->g_renderer);
   status = SDL_SetRenderDrawColor(hypervisor->g_renderer, 0xFF, 0xFF, 0xFF, SDL_ALPHA_OPAQUE);
-  // status = SDL_SetRenderDrawColor(hypervisor->g_renderer, kBackgroundColor, kBackgroundColor, kBackgroundColor,
-  //                                 SDL_ALPHA_OPAQUE);
-  // SDL_RenderFillRect(hypervisor->g_renderer, &game_rect);
   SDL_assert(status == 0);
   SDL_RenderFillRect(hypervisor->g_renderer, NULL);
   SDL_RenderPresent(hypervisor->g_renderer);
@@ -353,6 +351,7 @@ static uint8_t system_init(hypervisor_s* hypervisor) {
   load_scorefile(hypervisor);
   SDL_initFramerate(&hypervisor->fps_manager);
   SDL_setFramerate(&hypervisor->fps_manager, kFrameRate);
+  dinorunner_seed((unsigned short)time(NULL));
   status = dinorunner_init(&hypervisor->dinorunner, &kGameDimension, hypervisor);
   return status;
 }

dinorunner/CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.10)
 cmake_policy(PUSH)
 
 project(dinorunner 
-    VERSION 1.3.1
+    VERSION 1.3.2
     DESCRIPTION "Chrome's Dino game in C"
     LANGUAGES C)
 

dinorunner/include/dinorunner.h

@@ -594,6 +594,13 @@ void dinorunner_onkeydown(struct dinorunner_s* dinorunner);
  */
 void dinorunner_onkeynone(struct dinorunner_s* dinorunner);
 
+/**
+ * @brief Reinitialize pseudo-random value generator start value
+ * 
+ * @param random_seed Start value to reinitialize with
+ */
+void dinorunner_seed(unsigned short random_seed);
+
 /**
  * @defgroup Internal functions
  * Used internally by the dinorunner routines
@@ -640,7 +647,7 @@ unsigned char dinorunner_distancemeter_update(struct distance_meter_s* distance_
 void dinorunner_nightmode_init(struct nightmode_s* nightmode, unsigned width);
 void dinorunner_nightmode_reset(struct nightmode_s* nightmode, unsigned container_width, void* user_data);
 unsigned char dinorunner_nightmode_update(struct nightmode_s* nightmode, unsigned char show_nightmode,
-                                          unsigned container_width, void* user_data);
+                                          unsigned container_width, float current_speed, void* user_data);
 
 unsigned char dinorunner_trex_init(struct trex_s* trex, unsigned container_width, unsigned container_height,
                                    void* user_data);

dinorunner/src/dinorunner.c

@@ -39,7 +39,7 @@ unsigned char dinorunner_init(struct dinorunner_s* dinorunner, const struct dime
   dinorunner->user_data        = user_data;
   dinorunner->inverted         = 0u;
   res &= dinorunner_horizon_init(&dinorunner->horizon, &dinorunner->dimension,
-                                 -DINORUNNER_CONFIG_HORIZON_GAP_COEFFICIENT, dinorunner->user_data);
+                                 DINORUNNER_CONFIG_HORIZON_GAP_COEFFICIENT, dinorunner->user_data);
   res &= dinorunner_trex_init(&dinorunner->trex, dimension->width, dimension->height, dinorunner->user_data);
   res &= dinorunner_gameoverpanel_init(&dinorunner->gameoverpanel, dimension);
   res &= dinorunner_distancemeter_init(&dinorunner->distance_meter, &text_dimension, dimension->width,

dinorunner/src/horizon.c

@@ -162,7 +162,7 @@ unsigned char dinorunner_horizon_update(struct horizon_s* horizon, float delta_t
                                         void* user_data) {
   horizon->running_time += delta_time;
   dinorunner_horizonline_update(&horizon->horizon_line, delta_time, current_speed, user_data);
-  dinorunner_nightmode_update(&horizon->nightmode, show_night_mode, horizon->dimension.width, user_data);
+  dinorunner_nightmode_update(&horizon->nightmode, show_night_mode, horizon->dimension.width, current_speed, user_data);
   update_clouds(horizon, delta_time, current_speed, user_data);
   if (update_obstacles_request) {
     update_obstacles(horizon, delta_time, current_speed, user_data);

dinorunner/src/nightmode.c

@@ -8,10 +8,11 @@
 
 #include "dinorunner.h"
 
-static float dinorunner_nightmode_updateXPos(float current_pos, float speed, unsigned container_width) {
+static float dinorunner_nightmode_updateXPos(float current_pos, float speed, unsigned container_width,
+                                             float runner_speed) {
   if (current_pos < -DINORUNNER_CONFIG_NIGHTMODE_WIDTH) {
     current_pos = container_width;
-  } else {
+  } else if (runner_speed != 0) {
     current_pos -= speed;
   }
   return current_pos;
@@ -56,7 +57,7 @@ void dinorunner_nightmode_init(struct nightmode_s* nightmode, unsigned container
 }
 
 unsigned char dinorunner_nightmode_update(struct nightmode_s* nightmode, unsigned char show_nightmode,
-                                          unsigned container_width, void* user_data) {
+                                          unsigned container_width, float current_speed, void* user_data) {
   if (show_nightmode && nightmode->opacity == 0) {
     nightmode->current_phase++;
     if (nightmode->current_phase >= DINORUNNER_CONFIG_NIGHTMODE_MOONPHASES) {
@@ -71,12 +72,12 @@ unsigned char dinorunner_nightmode_update(struct nightmode_s* nightmode, unsigne
     nightmode->opacity -= DINORUNNER_CONFIG_NIGHTMODE_FADESPEED;
   }
   if (nightmode->opacity > 0) {
-    nightmode->x_pos =
-        dinorunner_nightmode_updateXPos(nightmode->x_pos, DINORUNNER_CONFIG_NIGHTMODE_MOONSPEED, container_width);
+    nightmode->x_pos = dinorunner_nightmode_updateXPos(nightmode->x_pos, DINORUNNER_CONFIG_NIGHTMODE_MOONSPEED,
+                                                       container_width, current_speed);
     if (nightmode->draw_stars) {
       for (unsigned i = 0; i < DINORUNNER_CONFIG_NIGHTMODE_NUMBSTARS; ++i) {
         nightmode->stars[i].x = dinorunner_nightmode_updateXPos(
-            nightmode->stars[i].x, (float)DINORUNNER_CONFIG_NIGHTMODE_STARSPEED, container_width);
+            nightmode->stars[i].x, (float)DINORUNNER_CONFIG_NIGHTMODE_STARSPEED, container_width, current_speed);
       }
     }
     dinorunner_nightmode_draw(nightmode, user_data);
@@ -91,5 +92,5 @@ unsigned char dinorunner_nightmode_update(struct nightmode_s* nightmode, unsigne
 void dinorunner_nightmode_reset(struct nightmode_s* nightmode, unsigned container_width, void* user_data) {
   nightmode->current_phase = 0;
   nightmode->opacity       = 0;
-  dinorunner_nightmode_update(nightmode, 0, container_width, user_data);
+  dinorunner_nightmode_update(nightmode, 0, container_width, 0, user_data);
 }

dinorunner/src/obstacle.c

@@ -154,7 +154,6 @@ static void obstacle_draw(const struct obstacle_s* obstacle, void* user_data) {
 void dinorunner_obstacle_init(struct obstacle_s* obstacle, enum obstacle_type_e obstacle_type,
                               const struct dimension_s* dimension, float gap_coefficient, float speed, int opt_x_offset,
                               void* user_data) {
-  TREX_UNUSED(gap_coefficient);
   obstacle->y_pos         = 0;
   obstacle->width         = 0;
   obstacle->gap           = 0;
@@ -173,7 +172,7 @@ void dinorunner_obstacle_init(struct obstacle_s* obstacle, enum obstacle_type_e
   obstacle->gap                        = 0u;
   obstacle->timer                      = 0u;
   obstacle->following_obstacle_created = 0u;
-  obstacle->gap_coefficient            = DINORUNNER_CONFIG_MAX_GAP_COEFFICIENT;
+  obstacle->gap_coefficient            = gap_coefficient;
   if (obstacle->size > 1 && (obstacle->config.multiple_speed > speed)) {
     obstacle->size = 1;
   }

dinorunner/src/utils.c

@@ -84,16 +84,18 @@ unsigned dinorunner_rand(void) {
 
 float dinorunner_srand(void) {
   unsigned rand = dinorunner_rand();
-  return (float)rand / 0xFFFF;
+  return (float)rand / (unsigned short)(-1);
 }
 
 unsigned dinorunner_getrandomnumb(unsigned min_value, unsigned max_value) {
-  unsigned value = dinorunner_rand();
-  value %= (max_value + 1);
-  if (value >= max_value) {
-    value = max_value;
-  } else if (value <= min_value) {
-    value = min_value;
+  float random_value = dinorunner_srand();
+  if (min_value > max_value) {
+    min_value = max_value;
   }
-  return value;
+  unsigned interval = max_value - min_value;
+  return min_value + dinorunner_roundf(random_value * interval);
 }
+
+void dinorunner_seed(unsigned short random_seed) {
+  lfsr = random_seed;
+}