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authorLeo Tenenbaum <pommicket@gmail.com>2020-11-28 21:44:33 -0500
committerLeo Tenenbaum <pommicket@gmail.com>2020-11-28 21:44:33 -0500
commit0826ab93914b508f9a37edf6bd4307bb0ecea14c (patch)
tree4caa1a8c212e6cd0319b01ad681845f5650cbf00 /buffer.c
parentcac24ffa13dc969244fb171b9aad565311c69f16 (diff)
started cursor stuff
Diffstat (limited to 'buffer.c')
-rw-r--r--buffer.c68
1 files changed, 51 insertions, 17 deletions
diff --git a/buffer.c b/buffer.c
index f06ca00..5af9ff6 100644
--- a/buffer.c
+++ b/buffer.c
@@ -7,6 +7,7 @@
#include "util.c"
#include "text.h"
+// @TODO: make this bigger -- maybe 4000 (it's small now to test having a bunch of blocks)
#define TEXT_BLOCK_MAX_SIZE 400
// Once two adjacent blocks are at most this big, combine them into
// one bigger text block.
@@ -20,9 +21,16 @@ typedef struct {
char *contents;
} TextBlock;
+// a position in the buffer
+typedef struct {
+ u32 block;
+ u32 idx;
+} BufferPos;
+
typedef struct {
double scroll_x, scroll_y; // number of characters scrolled in the x/y direction
Font *font;
+ BufferPos cursor_pos;
u8 tab_width;
float x1, y1, x2, y2;
u32 nblocks; // number of text blocks
@@ -126,35 +134,46 @@ void buffer_free(TextBuffer *buffer) {
free(blocks);
}
+// advance line and col according to the character c
+// either can be NULL
+static void buffer_update_line_col(TextBuffer *buffer, u64 *line, u64 *col, int c) {
+ if (line) {
+ if (c == '\n') ++*line;
+ }
+ if (col) {
+ switch (c) {
+ case '\n':
+ *col = 0;
+ break;
+ case '\r': break;
+ case '\t':
+ do
+ ++*col;
+ while (*col % buffer->tab_width);
+ break;
+ default:
+ ++*col;
+ break;
+ }
+ }
+}
+
// returns the number of lines of text in the buffer into *lines (if not NULL),
// and the number of columns of text, i.e. the length of the longest line, into *cols (if not NULL)
static void buffer_text_dimensions(TextBuffer *buffer, u64 *lines, u64 *cols) {
- u64 nlines = 1;
+ // @OPTIMIZE
+ u64 line = 1;
u64 maxcol = 0;
u64 col = 0;
for (u32 i = 0; i < buffer->nblocks; ++i) {
TextBlock *block = &buffer->blocks[i];
for (char *p = block->contents, *end = p + block->len; p != end; ++p) {
- switch (*p) {
- case '\n':
- ++nlines;
- col = 0;
- break;
- case '\r': break;
- case '\t':
- do
- ++col;
- while (col % buffer->tab_width);
- break;
- default:
- ++col;
- break;
- }
+ buffer_update_line_col(buffer, &line, &col, *p);
if (col > maxcol)
maxcol = col;
}
}
- if (lines) *lines = nlines;
+ if (lines) *lines = line;
if (cols) *cols = maxcol;
}
@@ -197,6 +216,21 @@ void buffer_scroll(TextBuffer *buffer, double dx, double dy) {
buffer_correct_scroll(buffer);
}
+// returns the line and column of the given buffer position.
+// line/col can be NULL.
+void buffer_pos_to_line_col(TextBuffer *buffer, BufferPos pos, u64 *line, u64 *col) {
+ // @TODO
+}
+
+// returns the position of the character at the given position in the buffer.
+// x/y can be NULL.
+void buffer_pos_to_pixels(TextBuffer *buffer, BufferPos pos, float *x, float *y) {
+ u64 line, col;
+ buffer_pos_to_line_col(buffer, pos, &line, &col);
+ if (x) *x = ((double)col - buffer->scroll_x) * font_char_width(buffer->font);
+ if (y) *y = ((double)line - buffer->scroll_y) * font_char_height(buffer->font);
+}
+
// Render the text buffer in the given rectangle
// NOTE: also corrects scroll
void buffer_render(TextBuffer *buffer, float x1, float y1, float x2, float y2) {