Add simple documentation in comments, refactor.

Change all `unsigned int` and `unsigned long` types to `size_t`.
Fix names alignment in headers.

Add documentation and simple description:
Painter - painter.h
Main - tetris.c
Unicode - unicode.h
IDList - idlist.h
Engine - engine.c

Minor changes:
tetris.c - fix indentation and code blocks separation with newlines,
remove unused includes.
idlist.h - fix structure field name alignment.
field.h, engine.c - define aliases for ghost and active shapes indexes
in the field.
engine.c - rename menuTick to snake case, fix curly braces style of
functions.
Makefile - switch SFML deprecated warnings off.

8 files changed, 125 insertions, 78 deletions

diff --git a/include/common.h b/include/common.h
index 3273c66..76293c5 100644
--- a/include/common.h
+++ b/include/common.h
@@ -1,14 +1,14 @@
 struct game {
-    unsigned int level;
-    int          started;
-    int          paused;
-    int          scoreCurrent;
-    int          moveLatency;
-    int          lines;
-    sfClock     *gameTick;
-    sfClock     *putTick;
-    sfClock     *mTick;
-    sfClock     *repPushDown;  // repeat latency when hold Down arrow
-    sfClock     *repKeyLeft;   // repeat latency when hold Left arrow
-    sfClock     *repKeyRight;  // repeat latency when hold Right arrow
+    size_t      level;
+    int         started;
+    int         paused;
+    int         scoreCurrent;
+    int         moveLatency;
+    int         lines;
+    sfClock    *gameTick;
+    sfClock    *putTick;
+    sfClock    *mTick;
+    sfClock    *repPushDown;  // repeat latency when hold Down arrow
+    sfClock    *repKeyLeft;   // repeat latency when hold Left arrow
+    sfClock    *repKeyRight;  // repeat latency when hold Right arrow
 };
diff --git a/include/field.h b/include/field.h
index c63a836..4e97aa8 100644
--- a/include/field.h
+++ b/include/field.h
@@ -3,9 +3,12 @@
 
 #define SHP_ATTR_GHOST              (1 << 0)
 
+#define GHOST_SHAPE_INDEX   0
+#define ACTIVE_SHAPE_INDEX  1
+
 struct cell {
-    char a; // active/empty state of cell
-    unsigned int color;
+    char    a; // active/empty state of cell
+    size_t  color;
 };
 
 /*
@@ -26,36 +29,36 @@ struct cell {
  */
 
 struct shape {
-    struct vector2i; // position
-    int t; // shape type
-    unsigned int attr;
-    char c[4][4];
+    struct  vector2i; // position
+    int     t; // shape type
+    size_t  attr;
+    char    c[4][4];
 };
 
 struct field {
-    unsigned long    id;
-    unsigned int     attr;
-    struct vector2i  pos;
-    struct vector2ui size;
-    struct vector2ui bound;
-    struct cell    **c; // array of logic shape cells
-    unsigned int     shape_cnt;
-    struct shape    *shape;
+    size_t              id;
+    size_t              attr;
+    struct vector2i     pos;
+    struct vector2ui    size;
+    struct vector2ui    bound;
+    struct cell       **c; // array of logic shape cells
+    size_t              shape_cnt;
+    struct shape       *shape;
 };
 
-void field_init(struct field *fld);
-void field_deinit(struct field *fld);
-void field_fill_random(struct field *fld);
-void field_clear(struct field *fld);
-void field_rotate_shape_clockwise(struct field *fld, unsigned int index);
-int  field_move_shape_down(struct field *fld, unsigned int index);
-int  field_move_shape_left(struct field *fld, unsigned int index);
-int  field_move_shape_right(struct field *fld, unsigned int index);
-void field_put_shape(struct field *fld, struct shape *shape);
-void field_reset_walking_shape(struct field *fld, unsigned int index);
-int  field_rm_lines(struct field *fld);
-int  field_shape_collision(struct field *fld, struct shape *shape);
-int  field_shape_out_of_bounds(struct field *fld, struct shape *shape);
-
-void shape_load(struct shape *shape);
-void shape_gen_random(struct shape *shape);
+void    field_init(struct field *fld);
+void    field_deinit(struct field *fld);
+void    field_fill_random(struct field *fld);
+void    field_clear(struct field *fld);
+void    field_rotate_shape_clockwise(struct field *fld, size_t index);
+int     field_move_shape_down(struct field *fld, size_t index);
+int     field_move_shape_left(struct field *fld, size_t index);
+int     field_move_shape_right(struct field *fld, size_t index);
+void    field_put_shape(struct field *fld, struct shape *shape);
+void    field_reset_walking_shape(struct field *fld, size_t index);
+int     field_rm_lines(struct field *fld);
+int     field_shape_collision(struct field *fld, struct shape *shape);
+int     field_shape_out_of_bounds(struct field *fld, struct shape *shape);
+
+void    shape_load(struct shape *shape);
+void    shape_gen_random(struct shape *shape);
diff --git a/include/idlist.h b/include/idlist.h
index 3318be4..c006a32 100644
--- a/include/idlist.h
+++ b/include/idlist.h
@@ -1,13 +1,22 @@
+/*
+ * idlist.h
+ *
+ * IDList - List datatype implementation. Element can be taken by id only.
+ *
+ * IDList is used by the Painter module and loadable texts.
+ *
+ * */
+
 struct idlist {
-    unsigned long id;
-    void        *obj;
-    struct idlist *next;
-    struct idlist *prev;
+    size_t          id;
+    void           *obj;
+    struct idlist  *next;
+    struct idlist  *prev;
 };
 
-struct idlist *list_new();
-struct idlist *list_append(struct idlist *list);
-struct idlist *list_get(const struct idlist *list, unsigned long id);
-void           list_rm_node(struct idlist *node);
-void           list_foreach(struct idlist *list, void (*job)(void *));
-void           list_destroy(struct idlist *list);
+struct idlist  *list_new();
+struct idlist  *list_append(struct idlist *list);
+struct idlist  *list_get(const struct idlist *list, size_t id);
+void            list_rm_node(struct idlist *node);
+void            list_foreach(struct idlist *list, void (*job)(void *));
+void            list_destroy(struct idlist *list);
diff --git a/include/painter.h b/include/painter.h
index 7bcb47a..fc01092 100644
--- a/include/painter.h
+++ b/include/painter.h
@@ -1,15 +1,40 @@
-void          painter_set_window(sfRenderWindow *window);
+/*
+ * painter.h
+ *
+ * Painter is a module for drawing tetris objects on a window. It is implemented
+ * as a singletone as OO programmers speak. It internally has global static
+ * arrays for objects referenced by handles. You register an object and get a
+ * handle (id) which can be used for updating an object - modifying it's
+ * drawable representation. Painter is used as described in following steps:
+ *
+ * 1. At first assign a window via painter_set_window() function.
+ * 2. Load a font if you are going to draw any text.
+ * 3. Register an object (field, text, etc.) using painter_register_*()
+ *    function.
+ * 4. Update an object attribute using painter_update_*() function. Update all
+ *    your objects for next frame before drawing.
+ * 5. Draw everything using painter_draw() function. Objects are drawn in order
+ *    they were registered.
+ * 6. At the end you must destroy your drawable objects and fonts. Objects are
+ *    registered each in it's own way, but have unified interface for
+ *    destroying - painter_destroy_drawable() function. You can destroy them
+ *    all at once using painter_destroy_drawables() function or even destroy
+ *    everything that has been allocated by the Painter, even loaded fonts.
+ *
+ * */
 
-void          painter_load_font(char *filename);
-void          painter_destroy_font();
+void    painter_set_window(sfRenderWindow *window);
 
-unsigned long painter_register_field(struct field *fld);
-void          painter_update_field(unsigned long id, struct field *fld);
-unsigned long painter_register_text(struct text *txt);
-void          painter_update_text(unsigned long id, struct text *txt);
+void    painter_load_font(char *filename);
+void    painter_destroy_font();
 
-void          painter_draw();
+size_t  painter_register_field(struct field *fld);
+void    painter_update_field(size_t id, struct field *fld);
+size_t  painter_register_text(struct text *txt);
+void    painter_update_text(size_t id, struct text *txt);
 
-void          painter_destroy_drawable(unsigned long id);
-void          painter_destroy_drawables();
-void          painter_destroy_all();
+void    painter_draw();
+
+void    painter_destroy_drawable(size_t id);
+void    painter_destroy_drawables();
+void    painter_destroy_all();
diff --git a/include/tet_conf.h b/include/tet_conf.h
index c5a6153..33a637f 100644
--- a/include/tet_conf.h
+++ b/include/tet_conf.h
@@ -52,7 +52,7 @@
 #define RM_2LINES_SCORE 100
 #define RM_3LINES_SCORE 300
 #define RM_4LINES_SCORE 1200
-#define LEVELUP_LINES 10
+#define LEVELUP_LINES   10
 
 #define FLD_SIZE_Y  22
 #define FLD_SIZE_X  10
diff --git a/include/text.h b/include/text.h
index 5c2dc5d..d8d9a47 100644
--- a/include/text.h
+++ b/include/text.h
@@ -1,15 +1,15 @@
-#define TXT_ATTR_INVISIBLE      (1 << 0)
+#define TXT_ATTR_INVISIBLE (1 << 0)
 
 typedef struct text {
-    char             *type;
-    char             *scene;
-    char             *font;
-    wchar_t          *text;
-    unsigned int      size;
-    struct vector2ui  pos;
-    unsigned int      attr;
-    unsigned long     id;
+    char               *type;
+    char               *scene;
+    char               *font;
+    wchar_t            *text;
+    size_t              size;
+    struct vector2ui    pos;
+    size_t              attr;
+    size_t              id;
 } Text;
 
-struct idlist *load_texts(char *filename);
-void           text_destroy(void *text);
+struct idlist  *load_texts(char *filename);
+void            text_destroy(void *text);
diff --git a/include/unicode.h b/include/unicode.h
index 0a34ce3..4e5910a 100644
--- a/include/unicode.h
+++ b/include/unicode.h
@@ -1,2 +1,12 @@
-unsigned long  utf8_strlen(char *string);
-void           utf8to32_strcpy(wchar_t *dest, char *src);
+/*
+ * unicode.h
+ *
+ * Unicode - module with some helper unicode functions.
+ *
+ * SFML uses UTF32 encoding for texts and there is no need to use any full
+ * featured library just for a couple of encoding conversion functions.
+ *
+ * */
+
+size_t  utf8_strlen(char *string);
+void    utf8to32_strcpy(wchar_t *dest, char *src);
diff --git a/include/vector.h b/include/vector.h
index fb00384..71ca579 100644
--- a/include/vector.h
+++ b/include/vector.h
@@ -3,5 +3,5 @@ struct vector2i {
 };
 
 struct vector2ui {
-    unsigned int x, y;
+    size_t x, y;
 };