*
* Windows can be almost any width (number has to fit into 16 bits); the virtual
* screen grows with them as needed -- but only horizontally and only up to 2^16
- * cells. Their height is limited by the height of the terminal screen.
+ * cells. Their height is limited by the height of the terminal screen, which
+ * must also fit into 2^16 cells.
*
* Positioning of windows can only indirectly be influenced: by resizing them,
* and by shifting their relative position inside the (currently invisible)
*
* Functions that return uint8_t return these error codes:
* 0 - success
- * 1 - memory allocation error (of ncurses' pads/windows, or scroll hint texts)
- * 2 - activity forces virtual screen to grow beyond width of 2^16 cells
+ * 1 - memory allocation error
+ * 2 - would force virtual screen to grow beyond width or height of 2^16 cells
+ *
+ * TODO: Expose less internals to the API.
*
* TODO: Think up a more intuitive window positioning algorithm or at least make
* the chain that windows are positioned by visible.
struct Win
{
- /* members supposed to be used ONLY INTERNALLY */
- struct Win * _prev; /* chain pointers; if 0, they mark the start or end */
- struct Win * _next; /* of the chain; if both are 0, Win is outside chain */
- struct yx_uint16 _start; /* upper left corner of "frame" WINDOW */
- char * _title; /* title to be used in window title bar */
- void (* _draw) (struct Win *); /* how to draw window content ("data") */
-
- /* members to be available EXTERNALLY */
+ struct Win * prev; /* chain pointers; if 0, they mark the start or end */
+ struct Win * next; /* of the chain; if both are 0, Win is outside chain */
+ struct yx_uint16 start; /* upper left corner of "frame" WINDOW */
+ char * title; /* title to be used in window title bar */
+ void (* draw) (struct Win *); /* how to draw window content ("data") */
struct Frame frame;
- void * data; /* window content to be drawn by _draw() */
+ void * data; /* window content to be drawn by _draw() */
};
*/
struct WinMeta
{
- /* members supposed to be used ONLY INTERNALLY */
- WINDOW * _screen; /* ncurses' pointer to the terminal screen */
- struct Win * _chain_start; /* first Win in chain; its _prev == 0 */
- struct Win * _chain_end; /* last Win in chain; its _next == 0 */
-
- /* members to be available EXTERNALLY */
- uint16_t pad_offset; /* number of cells view is moved to the right */
- struct Frame padframe; /* virtual screen fitted into terminal screen */
- struct Win * active; /* Win highlighted/selected for manipulation */
+ WINDOW * screen; /* ncurses' pointer to the terminal screen */
+ struct Win * chain_start; /* first Win in chain; its _prev == 0 */
+ struct Win * chain_end; /* last Win in chain; its _next == 0 */
+ uint16_t pad_offset; /* number of cells view is moved to the right */
+ struct Frame padframe; /* virtual screen fitted into terminal screen */
+ struct Win * active; /* Win highlighted/selected for manipulation */
};
* initialized 0, except for the virtual screen (height = that of the terminal
* screen; width = 1) amd its frame sized to the size of the terminal screen.
*/
-extern uint8_t init_win_meta(WINDOW * screen, struct WinMeta * wmeta);
+extern uint8_t init_win_meta(WINDOW * screen, struct WinMeta ** wmeta);
-/* Create a window below inside "wmeta" titled "title" of "height" and "width"
- * and appointing "func"() to interpret and draw the content stored at "data"
- * if the window is visible.
+/* Initialize a window child of "wmeta" to "title", "height" and "width" and
+ * appointing "func"() to interpret and draw the content stored at "data" when
+ * the window is visible.
*
- * A value for "width" <1 will trigger a fallback to width=1. A "height" <1 or
- * larger than the maximum window height possible within the virtual screen will
- * trigger a fallback to the maximum height possible (i.e. pass a "height" of 0
- * to initialize the window to its largest possible height).
+ * Pass 0 for "width" to make the window as wide as the terminal screen. Pass
+ * negative values for "width" to make the width so many cells smaller than that
+ * of the terminal screen. Pass 0 for "height" to give the window the maximum
+ * allowed height: one cell smaller than that of the terminal screen. Pass
+ * negative values to make the window width so many cells smaller than that of
+ * the terminal screen. The maximum allowed height is also applied for positive
+ * values that exceed it or negative values that would reduce the window height
+ * < 1 cell.
*
- * Other values of the Win struct will be initialized to 0. The window will stay
- * invisible until appended to the chain of visible windows via append_win().
+ * Other members of the Win struct are initialized to 0.
*/
-extern struct Win init_win(struct WinMeta * wmeta, char * title,
- uint16_t height, uint16_t width,
- void * data, void * func);
+extern uint8_t init_win(struct WinMeta * wmeta, struct Win ** w, char * title,
+ int16_t height, int16_t width,
+ void * data, void * func);
+
+
+
+/* Free allocated memory for an initialized Win / WinMeta struct. */
+extern void free_winmeta(struct WinMeta * wmeta);
+extern void free_win(struct Win * win);
-/* Append/suspend window "w" to/from chain of visible windows in "wmeta".
+/* Append/suspend window "w" to/from chain of visible windows below "wmeta".
* Appended windows will become active. Suspended active windows will move the
* active window selection to their successor in the window chain or, failing
* that, their predecessor; if no window remains, none will be active.
/* Apply new size "size" to the active window, but only if it provides for at
* least one cell width/height and is in height at least one cell smaller than
- * the screen's vertical height (to provide space for the title bar).
+ * the screen's vertical height (to provide space for the title bar). Does
+ * nothing if no window is active.
*/
extern uint8_t resize_active_win(struct WinMeta * wmeta, struct yx_uint16 size);
-/* Cycle active window selection forwards (set dir="n") or backwards. Wrap
- * around in the windows chain if start / end of it is met.
+/* Cycle active window selection forwards ("dir" == "f") or backwards (any
+ * other "dir"). Wrap around in the windows chain if start / end of it is met.
+ * Does nothing if no window is active.
*/
extern void cycle_active_win(struct WinMeta * wmeta, char dir);
-/* Move active window forwards (set dir="f") or backwards (set dir="b"). Wrap
- * around in the window chain if start / end of it is met.
+/* Move active window forwards ("dir" == "f") or backwards (any other "dir").
+ * Wrap around in the window chain if start / end of it is met. Does nothing if
+ * no window is active.
*/
extern uint8_t shift_active_win(struct WinMeta * wmeta, char dir);
* further into a certain direction) into "frame" at position "pos" (describing
* a column or a row dependent on "dir" being *either* "<"/">" *or* something
* else). It will consist of a line of "dir" symbols bracketing a descriptive
- * text stating the number of rows/columns further available beyond the hint.
+ * text stating "dist" as the number of rows/columns further available beyond
+ * the hint.
*/
extern uint8_t draw_scroll_hint(struct Frame * frame, uint16_t pos,
uint32_t dist, char dir);