diff options
| -rw-r--r-- | buffer.c | 206 | ||||
| -rw-r--r-- | main.c | 18 |
2 files changed, 167 insertions, 57 deletions
@@ -1,4 +1,5 @@ // Text buffers - These store the contents of a file. +#include <wctype.h> #include "unicode.h" #include "util.c" #include "text.h" @@ -433,14 +434,50 @@ BufferPos buffer_end_pos(TextBuffer *buffer) { return (BufferPos){.line = buffer->nlines - 1, .index = buffer->lines[buffer->nlines-1].len}; } +// if the cursor is offscreen, this will scroll to make it onscreen. +static void buffer_scroll_to_cursor(TextBuffer *buffer) { + i64 cursor_line = buffer->cursor_pos.line; + i64 cursor_col = buffer_index_to_column(buffer, (u32)cursor_line, buffer->cursor_pos.index); + i64 display_lines = buffer_display_rows(buffer); + i64 display_cols = buffer_display_cols(buffer); + double scroll_x = buffer->scroll_x, scroll_y = buffer->scroll_y; + i64 scroll_padding = 5; + + // scroll left if cursor is off screen in that direction + double max_scroll_x = (double)(cursor_col - scroll_padding); + scroll_x = util_mind(scroll_x, max_scroll_x); + // scroll right + double min_scroll_x = (double)(cursor_col - display_cols + scroll_padding); + scroll_x = util_maxd(scroll_x, min_scroll_x); + // scroll up + double max_scroll_y = (double)(cursor_line - scroll_padding); + scroll_y = util_mind(scroll_y, max_scroll_y); + // scroll down + double min_scroll_y = (double)(cursor_line - display_lines + scroll_padding); + scroll_y = util_maxd(scroll_y, min_scroll_y); + + buffer->scroll_x = scroll_x; + buffer->scroll_y = scroll_y; + buffer_correct_scroll(buffer); // it's possible that min/max_scroll_x/y go too far +} + + +// ensures that `p` refers to a valid position. +static void buffer_pos_validate(TextBuffer *buffer, BufferPos *p) { + if (p->line >= buffer->nlines) + p->line = buffer->nlines - 1; + u32 line_len = buffer->lines[p->line].len; + if (p->index > line_len) + p->index = line_len; +} + // move left (if `by` is negative) or right (if `by` is positive) by the specified amount. // returns the signed number of characters successfully moved (it could be less in magnitude than `by` if the beginning of the file is reached) i64 buffer_pos_move_horizontally(TextBuffer *buffer, BufferPos *p, i64 by) { + buffer_pos_validate(buffer, p); if (by < 0) { by = -by; i64 by_start = by; - if (p->line >= buffer->nlines) - *p = buffer_end_pos(buffer); // invalid position; move to end of buffer while (by > 0) { if (by <= p->index) { @@ -489,6 +526,7 @@ i64 buffer_pos_move_horizontally(TextBuffer *buffer, BufferPos *p, i64 by) { // same as buffer_pos_move_horizontally, but for up and down. i64 buffer_pos_move_vertically(TextBuffer *buffer, BufferPos *pos, i64 by) { + buffer_pos_validate(buffer, pos); // moving up/down should preserve the column, not the index. // consider: // tab|hello world @@ -539,32 +577,125 @@ i64 buffer_pos_move_down(TextBuffer *buffer, BufferPos *pos, i64 by) { return +buffer_pos_move_vertically(buffer, pos, +by); } +i64 buffer_cursor_move_left(TextBuffer *buffer, i64 by) { + i64 ret = buffer_pos_move_left(buffer, &buffer->cursor_pos, by); + buffer_scroll_to_cursor(buffer); + return ret; +} -// if the cursor is offscreen, this will scroll to make it onscreen. -static void buffer_scroll_to_cursor(TextBuffer *buffer) { - i64 cursor_line = buffer->cursor_pos.line; - i64 cursor_col = buffer_index_to_column(buffer, (u32)cursor_line, buffer->cursor_pos.index); - i64 display_lines = buffer_display_rows(buffer); - i64 display_cols = buffer_display_cols(buffer); - double scroll_x = buffer->scroll_x, scroll_y = buffer->scroll_y; - i64 scroll_padding = 5; +i64 buffer_cursor_move_right(TextBuffer *buffer, i64 by) { + i64 ret = buffer_pos_move_right(buffer, &buffer->cursor_pos, by); + buffer_scroll_to_cursor(buffer); + return ret; +} - // scroll left if cursor is off screen in that direction - double max_scroll_x = (double)(cursor_col - scroll_padding); - scroll_x = util_mind(scroll_x, max_scroll_x); - // scroll right - double min_scroll_x = (double)(cursor_col - display_cols + scroll_padding); - scroll_x = util_maxd(scroll_x, min_scroll_x); - // scroll up - double max_scroll_y = (double)(cursor_line - scroll_padding); - scroll_y = util_mind(scroll_y, max_scroll_y); - // scroll down - double min_scroll_y = (double)(cursor_line - display_lines + scroll_padding); - scroll_y = util_maxd(scroll_y, min_scroll_y); +i64 buffer_cursor_move_up(TextBuffer *buffer, i64 by) { + i64 ret = buffer_pos_move_up(buffer, &buffer->cursor_pos, by); + buffer_scroll_to_cursor(buffer); + return ret; +} - buffer->scroll_x = scroll_x; - buffer->scroll_y = scroll_y; - buffer_correct_scroll(buffer); // it's possible that min/max_scroll_x/y go too far +i64 buffer_cursor_move_down(TextBuffer *buffer, i64 by) { + i64 ret = buffer_pos_move_down(buffer, &buffer->cursor_pos, by); + buffer_scroll_to_cursor(buffer); + return ret; +} + + +// move left / right by the specified number of words +// returns the number of words successfully moved forward +i64 buffer_pos_move_words(TextBuffer *buffer, BufferPos *pos, i64 nwords) { + buffer_pos_validate(buffer, pos); + if (nwords > 0) { + for (i64 i = 0; i < nwords; ++i) { // move forward one word `nwords` times + Line *line = &buffer->lines[pos->line]; + u32 index = pos->index; + char32_t const *str = line->str; + if (index == line->len) { + if (pos->line >= buffer->nlines - 1) { + // end of file reached + return i; + } else { + // end of line reached; move to next line + ++pos->line; + pos->index = 0; + } + } else { + // move past any whitespace before the word + while (index < line->len && iswspace(str[index])) + ++index; + + bool starting_alnum = iswalnum(str[index]) != 0; + for (; index < line->len && !iswspace(str[index]); ++index) { + bool this_alnum = iswalnum(str[index]) != 0; + if (this_alnum != starting_alnum) { + // either the position *was* on an alphanumeric character and now it's not + // or it wasn't and now it is. + break; + } + } + + // move past any whitespace after the word + while (index < line->len && iswspace(str[index])) + ++index; + pos->index = index; + } + } + return nwords; + } else if (nwords < 0) { + nwords = -nwords; + for (i64 i = 0; i < nwords; ++i) { + Line *line = &buffer->lines[pos->line]; + u32 index = pos->index; + char32_t const *str = line->str; + if (index == 0) { + if (pos->line == 0) { + // start of file reached + return i; + } else { + // start of line reached; move to previous line + --pos->line; + pos->index = buffer->lines[pos->line].len; + } + } else { + --index; + + while (index > 0 && iswspace(str[index])) + --index; + bool starting_alnum = iswalnum(str[index]) != 0; + for (; index > 0 && !iswspace(str[index]); --index) { + bool this_alnum = iswalnum(str[index]) != 0; + if (this_alnum != starting_alnum) { + break; + } + } + if (iswspace(str[index])) + ++index; + pos->index = index; + } + } + } + return 0; +} + +i64 buffer_pos_move_left_words(TextBuffer *buffer, BufferPos *pos, i64 nwords) { + return -buffer_pos_move_words(buffer, pos, -nwords); +} + +i64 buffer_pos_move_right_words(TextBuffer *buffer, BufferPos *pos, i64 nwords) { + return +buffer_pos_move_words(buffer, pos, +nwords); +} + +i64 buffer_cursor_move_left_words(TextBuffer *buffer, i64 nwords) { + i64 ret = buffer_pos_move_left_words(buffer, &buffer->cursor_pos, nwords); + buffer_scroll_to_cursor(buffer); + return ret; +} + +i64 buffer_cursor_move_right_words(TextBuffer *buffer, i64 nwords) { + i64 ret = buffer_pos_move_right_words(buffer, &buffer->cursor_pos, nwords); + buffer_scroll_to_cursor(buffer); + return ret; } // insert `number` empty lines starting at index `where`. @@ -671,31 +802,6 @@ static void buffer_shorten(TextBuffer *buffer, u32 new_nlines) { buffer->nlines = new_nlines; // @OPTIMIZE(memory): decrease lines capacity } -i64 buffer_cursor_move_left(TextBuffer *buffer, i64 by) { - i64 ret = buffer_pos_move_left(buffer, &buffer->cursor_pos, by); - buffer_scroll_to_cursor(buffer); - return ret; -} - -i64 buffer_cursor_move_right(TextBuffer *buffer, i64 by) { - i64 ret = buffer_pos_move_right(buffer, &buffer->cursor_pos, by); - buffer_scroll_to_cursor(buffer); - return ret; -} - -i64 buffer_cursor_move_up(TextBuffer *buffer, i64 by) { - i64 ret = buffer_pos_move_up(buffer, &buffer->cursor_pos, by); - buffer_scroll_to_cursor(buffer); - return ret; -} - -i64 buffer_cursor_move_down(TextBuffer *buffer, i64 by) { - i64 ret = buffer_pos_move_down(buffer, &buffer->cursor_pos, by); - buffer_scroll_to_cursor(buffer); - return ret; -} - - void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars) { u32 line_idx = pos.line; u32 index = pos.index; @@ -82,7 +82,8 @@ int main(void) { while (!quit) { SDL_Event event; - + Uint8 const *keyboard_state = SDL_GetKeyboardState(NULL); + bool ctrl = keyboard_state[SDL_SCANCODE_LCTRL] || keyboard_state[SDL_SCANCODE_RCTRL]; while (SDL_PollEvent(&event)) { // @TODO: make a function to handle text buffer events @@ -105,10 +106,16 @@ int main(void) { buffer_scroll(&text_buffer, 0, +buffer_display_rows(&text_buffer)); break; case SDLK_RIGHT: - buffer_cursor_move_right(&text_buffer, 1); + if (ctrl) + buffer_cursor_move_right_words(&text_buffer, 1); + else + buffer_cursor_move_right(&text_buffer, 1); break; case SDLK_LEFT: - buffer_cursor_move_left(&text_buffer, 1); + if (ctrl) + buffer_cursor_move_left_words(&text_buffer, 1); + else + buffer_cursor_move_left(&text_buffer, 1); break; case SDLK_UP: buffer_cursor_move_up(&text_buffer, 1); @@ -137,9 +144,6 @@ int main(void) { } } - Uint8 const *keyboard_state = SDL_GetKeyboardState(NULL); - bool control_key_down = keyboard_state[SDL_SCANCODE_LCTRL] || keyboard_state[SDL_SCANCODE_RCTRL]; - double frame_dt; { Uint32 time_this_frame = SDL_GetTicks(); @@ -147,7 +151,7 @@ int main(void) { time_at_last_frame = time_this_frame; } - if (control_key_down) { + if (ctrl) { // control + arrow keys to scroll double scroll_speed = 20.0; double scroll_amount_x = scroll_speed * frame_dt * 1.5; // characters are taller than they are wide |