X-Git-Url: https://plomlompom.com/repos/?a=blobdiff_plain;f=src%2Fwindows.h;h=9f1b02b8cf2b1b876c68fb48ec95b40436272a72;hb=550d22ec0c3f530f5d317746f3f7e75251a1de4b;hp=03d44b693e4fdb65e04c5a31a95bae1ab4fd2779;hpb=566ddf894142085e3f0208a08fa36ccce6d6a6ea;p=plomrogue diff --git a/src/windows.h b/src/windows.h index 03d44b6..9f1b02b 100644 --- a/src/windows.h +++ b/src/windows.h @@ -8,8 +8,9 @@ * (in a bizarre fashion, see below) automatically. * * Windows can be almost any width (number has to fit into 16 bits); the virtual - * screen grows with them as needed -- but only horizontally. Their height is - * limited by the height of the terminal screen. + * 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, 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) @@ -19,11 +20,15 @@ * that thrones over enough space to fit them in; failing that, they are placed * to the right of the window with the rightmost border. * + * Functions that return uint8_t return these error codes: + * 0 - success + * 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. - * - * TODO: Ensure there are only windows as many / as big as fit into the maximum - * size of the virtual screen. */ #ifndef WINDOWS_H @@ -31,86 +36,97 @@ -#include /* for uint16_t, uint32_t */ +#include /* for uint8_t, uint16_t, uint32_t */ #include /* for the WINDOW typedef */ #include "yx_uint16.h" /* for yx_uint16 coordinates */ -/* Individual windows consist of potential (real if window is visible) ncurses - * WINDOWs wrapped inside Frame structs (that keep a window's designated size - * even when it is invisible) wrapped inside metadata-rich Win structs. Win - * structs are chained into a linked list of all the windows visible on the - * virtual screen and also contain pointers to what content is to be drawn - * inside the window, and by use of what method. + +/* Individual windows consist of potential (real only if window is visible + * inside the virtual screen) ncurses WINDOWs wrapped inside Frame structs (that + * keep a window's designated size even when it is invisible) wrapped inside + * metadata-rich Win structs. Win structs are chained into a linked list of all + * the windows visible on the virtual screen and also contain pointers to what + * content is to be drawn inside the window, and by use of what method. */ -struct Frame -{ - WINDOW * curses_win; - struct yx_uint16 size; /* designated size of curses_win */ -}; +struct Frame /* If Frame is Win's "frame", "size" is the */ +{ /* designated size of curses_win's ncurses WINDOW. */ + WINDOW * curses_win; /* If Frame is WinMeta's "padframe", curses_win is */ + struct yx_uint16 size; /* the ncurses pad representing the virtual screen */ +}; /* and "size" desribes the terminal screen size. */ struct Win { - struct Win * prev; /* prev=next=0 if Win is outside the chain */ - struct Win * next; - struct yx_uint16 start; /* upper left corner (of WINDOW or border?) */ + 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; - char * title; /* title to be shown on window border top */ - void (* draw) (struct Win *); /* function to draw window content ("data") */ - void * data; /* content to be drawn; draw() knows how */ + void * data; /* window content to be drawn by _draw() */ }; -/* The window manager's parent struct WinMeta provides the virtual screen and a - * representation of the terminal screen. It also anchors start and end of the - * windows chain. +/* The window manager's parent struct WinMeta contains the virtual screen, + * relates it to the terminal screen and anchors the chain of visible windows. */ struct WinMeta { - WINDOW * screen; /* terminal screen */ + 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 pad; /* virtual screen */ - struct Win * chain_start; /* first Win, whose .prev shall point to 0 */ - struct Win * chain_end; /* last Win, whose .next shall point to 0 */ - struct Win * active; /* window highlighted/selected for manipulation */ + struct Frame padframe; /* virtual screen fitted into terminal screen */ + struct Win * active; /* Win highlighted/selected for manipulation */ }; -/* Create on the terminal "screen" an empty WinMeta whose virtual screen at the - * beginning is sized just like the terminal screen. Note that emptiness is - * marked by WinMeta.chain_start=0. Other struct values are also initialized 0. - * - * TODO: Why is an *empty* virtual screen's size that of the terminal screen? +/* Initialize empty WinMeta "wmeta" on the terminal "screen". (Note that + * emptiness is marked by WinMeta.chain_start=0.) Other struct members are also + * 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 struct WinMeta init_win_meta(WINDOW * screen); +extern uint8_t init_win_meta(WINDOW * screen, struct WinMeta ** wmeta); -/* Create a window below inside "wmeta" titled "title" 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. * - * The start size for the Frame will be a width of 20 cells and a height one - * less than the height of the virtual screen (so as to fit the title bar on top - * of the window). Other values will be initialized to 0. The window will stay - * invisible until appended to the chain of visible windows via append_win(). + * 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. * - * TODO: Why a default start width instead of passing a start width? + * Other members of the Win struct are initialized to 0. */ -extern struct Win init_win(struct WinMeta * wmeta, char * title, - 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. */ -extern void append_win(struct WinMeta * wmeta, struct Win * w); -extern void suspend_win(struct WinMeta * wmeta, struct Win * w); +extern uint8_t append_win(struct WinMeta * wmeta, struct Win * w); +extern uint8_t suspend_win(struct WinMeta * wmeta, struct Win * w); @@ -126,32 +142,34 @@ extern void reset_pad_offset(struct WinMeta * wmeta, uint16_t new_offset); /* 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 void resize_active_win(struct WinMeta * wmeta, struct yx_uint16 size); +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 void shift_active_win(struct WinMeta * wmeta, char dir); +extern uint8_t shift_active_win(struct WinMeta * wmeta, char dir); -/* Draw virtual screen including all windows. Also add scroll hints (a line - * stating that there is more to see on scrolling further into a certain - * direction) for where the edges of the terminal screen hit non-edges of and - * inside the virtual screen. Then update the terminal screen. +/* Draw virtual screen including all windows. Also add scroll hints (see comment + * on draw_scroll_hint()) for where the edges of the terminal screen hit + * non-edges of and inside the virtual screen. Then update the terminal screen. */ -extern void draw_all_wins(struct WinMeta * wmeta); +extern uint8_t draw_all_wins(struct WinMeta * wmeta); @@ -159,10 +177,11 @@ extern void draw_all_wins(struct WinMeta * wmeta); * 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 void draw_scroll_hint(struct Frame * frame, uint16_t pos, uint32_t dist, - char dir); +extern uint8_t draw_scroll_hint(struct Frame * frame, uint16_t pos, + uint32_t dist, char dir);