4coder/buffer/4coder_gap_buffer.cpp

296 lines
8.3 KiB
C++

/*
* Mr. 4th Dimention - Allen Webster
* Four Tech
*
* public domain -- no warranty is offered or implied; use this code at your own risk
*
* 23.10.2015
*
* Buffer data object
* type - Gap Buffer
*
*/
// TOP
typedef struct{
char *data;
int size1, gap_size, size2, max;
float *line_widths;
int *line_starts;
int line_count;
int line_max;
int widths_max;
} Gap_Buffer;
inline_4tech void
gap_buffer_initialize(Gap_Buffer *buffer, char *data, int size){
int size1, size2, gap_size;
assert_4tech(buffer->max >= size);
size1 = size >> 1;
size2 = size - size1;
gap_size = buffer->max - size1 - size2;
buffer->size1 = size1;
buffer->size2 = size2;
buffer->gap_size = gap_size;
if (buffer->size1 > 0){
memcpy_4tech(buffer->data, data, size1);
}
if (buffer->size2 > 0){
memcpy_4tech(buffer->data + size1 + gap_size, data + size1, size2);
}
}
inline_4tech int
buffer_size(Gap_Buffer *buffer){
int size;
size = buffer->size1 + buffer->size2;
return(size);
}
typedef struct{
Gap_Buffer *buffer;
char *data, *base;
int absolute_pos;
int pos, end;
int size;
int page_size;
int separated;
} Gap_Buffer_Stringify_Loop;
inline_4tech Gap_Buffer_Stringify_Loop
buffer_stringify_loop(Gap_Buffer *buffer, int start, int end, int page_size){
Gap_Buffer_Stringify_Loop result;
if (0 <= start && start < end && end <= buffer->size1 + buffer->size2){
result.buffer = buffer;
result.base = buffer->data;
result.page_size = page_size;
result.absolute_pos = start;
if (end <= buffer->size1) result.end = end;
else result.end = end + buffer->gap_size;
if (start < buffer->size1){
if (end <= buffer->size1) result.separated = 0;
else result.separated = 1;
result.pos = start;
}
else{
result.separated = 0;
result.pos = start + buffer->gap_size;
}
if (result.separated) result.size = buffer->size1 - start;
else result.size = end - start;
if (result.size > page_size) result.size = page_size;
result.data = buffer->data + result.pos;
}
else result.buffer = 0;
return(result);
}
inline_4tech int
buffer_stringify_good(Gap_Buffer_Stringify_Loop *loop){
int result;
result = (loop->buffer != 0);
return(result);
}
inline_4tech void
buffer_stringify_next(Gap_Buffer_Stringify_Loop *loop){
int size1, temp_end;
if (loop->separated){
size1 = loop->buffer->size1;
if (loop->pos + loop->size == size1){
loop->separated = 0;
loop->pos = loop->buffer->gap_size + size1;
loop->absolute_pos = size1;
temp_end = loop->end;
}
else{
loop->pos += loop->page_size;
loop->absolute_pos += loop->page_size;
temp_end = size1;
}
}
else{
if (loop->pos + loop->size == loop->end){
loop->buffer = 0;
temp_end = loop->pos;
}
else{
loop->pos += loop->page_size;
loop->absolute_pos += loop->page_size;
temp_end = loop->end;
}
}
loop->size = temp_end - loop->pos;
if (loop->size > loop->page_size) loop->size = loop->page_size;
loop->data = loop->base + loop->pos;
}
typedef struct{
Gap_Buffer *buffer;
char *data, *base;
int pos, end;
int size;
int absolute_pos;
int page_size;
int separated;
} Gap_Buffer_Backify_Loop;
inline_4tech Gap_Buffer_Backify_Loop
buffer_backify_loop(Gap_Buffer *buffer, int start, int end, int page_size){
Gap_Buffer_Backify_Loop result;
int chunk2_start;
if (0 <= end && end < start && start <= buffer->size1 + buffer->size2){
chunk2_start = buffer->size1 + buffer->gap_size;
result.buffer = buffer;
result.base = buffer->data;
result.page_size = page_size;
if (end < buffer->size1) result.end = end;
else result.end = end + buffer->gap_size;
if (start <= buffer->size1){
result.separated = 0;
result.pos = start - page_size;
}
else{
if (end < buffer->size1) result.separated = 1;
else result.separated = 0;
result.pos = start - page_size + buffer->gap_size;
}
if (result.separated){
if (result.pos < chunk2_start) result.pos = chunk2_start;
}
else{
if (result.pos < result.end) result.pos = result.end;
}
result.size = start - result.pos;
result.absolute_pos = result.pos;
if (result.absolute_pos > buffer->size1) result.absolute_pos -= buffer->gap_size;
result.data = result.base + result.pos;
}
else result.buffer = 0;
return(result);
}
inline_4tech int
buffer_backify_good(Gap_Buffer_Backify_Loop *loop){
int result;
result = (loop->buffer != 0);
return(result);
}
inline_4tech void
buffer_backify_next(Gap_Buffer_Backify_Loop *loop){
Gap_Buffer *buffer;
int temp_end;
int chunk2_start;
buffer = loop->buffer;
chunk2_start = buffer->size1 + buffer->gap_size;
if (loop->separated){
if (loop->pos == chunk2_start){
loop->separated = 0;
temp_end = buffer->size1;
loop->pos = temp_end - loop->page_size;
loop->absolute_pos = loop->pos;
if (loop->pos < loop->end){
loop->absolute_pos += (loop->end - loop->pos);
loop->pos = loop->end;
}
}
else{
temp_end = loop->pos;
loop->pos -= loop->page_size;
loop->absolute_pos -= loop->page_size;
if (loop->pos < chunk2_start){
loop->pos = chunk2_start;
loop->absolute_pos = buffer->size1;
}
}
}
else{
if (loop->pos == loop->end){
temp_end = 0;
loop->buffer = 0;
}
else{
temp_end = loop->pos;
loop->pos -= loop->page_size;
loop->absolute_pos -= loop->page_size;
if (loop->pos < loop->end){
loop->absolute_pos += (loop->end - loop->pos);
loop->pos = loop->end;
}
}
}
loop->size = temp_end - loop->pos;
loop->data = loop->base + loop->pos;
}
inline_4tech void
buffer_stringify(Gap_Buffer *buffer, int start, int end, char *out){
for (Gap_Buffer_Stringify_Loop loop = buffer_stringify_loop(buffer, start, end, end - start);
buffer_stringify_good(&loop);
buffer_stringify_next(&loop)){
memcpy_4tech(out, loop.data, loop.size);
out += loop.size;
}
}
internal_4tech Full_Cursor
buffer_cursor_seek(Gap_Buffer *buffer, Buffer_Seek seek, float max_width, float font_height,
void *advance_data, int stride, Full_Cursor cursor){
char *data;
int size1, size2, gap_size;
int total_size, end, i;
int step;
int result;
Seek_State state;
char *advances;
int xy_seek;
char ch;
data = buffer->data;
size1 = buffer->size1;
gap_size = buffer->gap_size;
size2 = buffer->size2;
total_size = size1 + gap_size + size2;
advances = (char*)advance_data;
xy_seek = (seek.type == buffer_seek_wrapped_xy || seek.type == buffer_seek_unwrapped_xy);
state.cursor = cursor;
result = 1;
i = cursor.pos;
end = size1;
for (step = 0; step < 2; ++step){
for (; i < end && result; ++i){
ch = data[i];
result = cursor_seek_step(&state, seek, xy_seek, max_width, font_height,
advances, stride, size1 + size2, ch);
}
end = total_size;
i += gap_size;
}
if (result){
result = cursor_seek_step(&state, seek, xy_seek, max_width, font_height,
advances, stride, size1 + size2, 0);
assert_4tech(result == 0);
}
return(state.cursor);
}
// BOTTOM