bool
page_is_visible(zathura_document_t *document, unsigned int page_number)
{
g_return_val_if_fail(document != NULL, false);
/* position at the center of the viewport */
double pos_x = zathura_document_get_position_x(document);
double pos_y = zathura_document_get_position_y(document);
/* get the center of page page_number */
double page_x, page_y;
page_number_to_position(document, page_number, 0.5, 0.5, &page_x, &page_y);
unsigned int cell_width, cell_height;
zathura_document_get_cell_size(document, &cell_height, &cell_width);
unsigned int doc_width, doc_height;
zathura_document_get_document_size(document, &doc_height, &doc_width);
unsigned int view_width, view_height;
zathura_document_get_viewport_size(document, &view_height, &view_width);
return ( fabs(pos_x - page_x) < 0.5 * (double)(view_width + cell_width) / (double)doc_width &&
fabs(pos_y - page_y) < 0.5 * (double)(view_height + cell_height) / (double)doc_height);
}
void
page_number_to_position(zathura_document_t* document, unsigned int page_number,
double xalign, double yalign, double* pos_x,
double* pos_y)
{
g_return_if_fail(document != NULL);
unsigned int c0 = zathura_document_get_first_page_column(document);
unsigned int npag = zathura_document_get_number_of_pages(document);
unsigned int ncol = zathura_document_get_pages_per_row(document);
unsigned int nrow = (npag + c0 - 1 + ncol - 1) / ncol; /* number of rows */
/* row and column for page_number indexed from 0 */
unsigned int row = (page_number + c0 - 1) / ncol;
unsigned int col = (page_number + c0 - 1) % ncol;
/* sizes of page cell, viewport and document */
unsigned int cell_height = 0, cell_width = 0;
zathura_document_get_cell_size(document, &cell_height, &cell_width);
unsigned int view_height = 0, view_width = 0;
zathura_document_get_viewport_size(document, &view_height, &view_width);
unsigned int doc_height = 0, doc_width = 0;
zathura_document_get_document_size(document, &doc_height, &doc_width);
/* compute the shift to align to the viewport. If the page fits to viewport, just center it. */
double shift_x = 0.5, shift_y = 0.5;
if (cell_width > view_width) {
shift_x = 0.5 + (xalign - 0.5) * ((double)cell_width - (double)view_width) / (double)cell_width;
}
if (cell_height > view_height) {
shift_y = 0.5 + (yalign - 0.5) * ((double)cell_height - (double)view_height) / (double)cell_height;
}
/* compute the position */
*pos_x = ((double)col + shift_x) / (double)ncol;
*pos_y = ((double)row + shift_y) / (double)nrow;
}
bool
sc_scroll(girara_session_t* session, girara_argument_t* argument,
girara_event_t* event, unsigned int t)
{
g_return_val_if_fail(session != NULL, false);
g_return_val_if_fail(session->global.data != NULL, false);
zathura_t* zathura = session->global.data;
g_return_val_if_fail(argument != NULL, false);
if (zathura->document == NULL) {
return false;
}
/* if TOP or BOTTOM, go there and we are done */
if (argument->n == TOP) {
position_set(zathura, -1, 0);
return false;
} else if (argument->n == BOTTOM) {
position_set(zathura, -1, 1.0);
return false;
}
/* Retrieve current page and position */
const unsigned int page_id = zathura_document_get_current_page_number(zathura->document);
double pos_x = zathura_document_get_position_x(zathura->document);
double pos_y = zathura_document_get_position_y(zathura->document);
/* If PAGE_TOP or PAGE_BOTTOM, go there and we are done */
if (argument->n == PAGE_TOP) {
double dontcare = 0.5;
page_number_to_position(zathura->document, page_id, dontcare, 0.0, &dontcare, &pos_y);
position_set(zathura, pos_x, pos_y);
return false;
} else if (argument->n == PAGE_BOTTOM) {
double dontcare = 0.5;
page_number_to_position(zathura->document, page_id, dontcare, 1.0, &dontcare, &pos_y);
position_set(zathura, pos_x, pos_y);
return false;
}
if (t == 0) {
t = 1;
}
unsigned int view_width = 0;
unsigned int view_height = 0;
zathura_document_get_viewport_size(zathura->document, &view_height, &view_width);
unsigned int doc_width = 0;
unsigned int doc_height = 0;
zathura_document_get_document_size(zathura->document, &doc_height, &doc_width);
float scroll_step = 40;
girara_setting_get(session, "scroll-step", &scroll_step);
float scroll_hstep = -1;
girara_setting_get(session, "scroll-hstep", &scroll_hstep);
if (scroll_hstep < 0) {
scroll_hstep = scroll_step;
}
float scroll_full_overlap = 0.0;
girara_setting_get(session, "scroll-full-overlap", &scroll_full_overlap);
bool scroll_page_aware = false;
girara_setting_get(session, "scroll-page-aware", &scroll_page_aware);
bool scroll_wrap = false;
girara_setting_get(session, "scroll-wrap", &scroll_wrap);
/* compute the direction of scrolling */
double direction = 1.0;
if ((argument->n == LEFT) || (argument->n == FULL_LEFT) || (argument->n == HALF_LEFT) ||
(argument->n == UP) || (argument->n == FULL_UP) || (argument->n == HALF_UP)) {
direction = -1.0;
}
const double vstep = (double)view_height / (double)doc_height;
const double hstep = (double)view_width / (double)doc_width;
/* compute new position */
switch (argument->n) {
case FULL_UP:
case FULL_DOWN:
pos_y += direction * (1.0 - scroll_full_overlap) * vstep;
break;
case FULL_LEFT:
case FULL_RIGHT:
pos_x += direction * (1.0 - scroll_full_overlap) * hstep;
break;
case HALF_UP:
case HALF_DOWN:
pos_y += direction * 0.5 * vstep;
break;
case HALF_LEFT:
case HALF_RIGHT:
pos_x += direction * 0.5 * hstep;
break;
case UP:
case DOWN:
pos_y += direction * t * scroll_step / (double)doc_height;
break;
case LEFT:
case RIGHT:
pos_x += direction * t * scroll_hstep / (double)doc_width;
break;
case BIDIRECTIONAL: {
pos_x += event->x * t * scroll_hstep / (double)doc_width;
pos_y += event->y * t * scroll_step / (double)doc_height;
break;
}
}
/* handle boundaries */
const double end_x = 0.5 * (double)view_width / (double)doc_width;
const double end_y = 0.5 * (double)view_height / (double)doc_height;
const double new_x = scroll_wrap ? 1.0 - end_x : end_x;
const double new_y = scroll_wrap ? 1.0 - end_y : end_y;
if (pos_x < end_x) {
pos_x = new_x;
} else if (pos_x > 1.0 - end_x) {
pos_x = 1 - new_x;
}
if (pos_y < end_y) {
pos_y = new_y;
} else if (pos_y > 1.0 - end_y) {
pos_y = 1 - new_y;
}
/* snap to the border if we change page */
const unsigned int new_page_id = position_to_page_number(zathura->document, pos_x, pos_y);
if (scroll_page_aware == true && page_id != new_page_id) {
double dummy = 0.0;
switch(argument->n) {
case FULL_LEFT:
case HALF_LEFT:
page_number_to_position(zathura->document, new_page_id, 1.0, 0.0, &pos_x, &dummy);
break;
case FULL_RIGHT:
case HALF_RIGHT:
page_number_to_position(zathura->document, new_page_id, 0.0, 0.0, &pos_x, &dummy);
break;
case FULL_UP:
case HALF_UP:
page_number_to_position(zathura->document, new_page_id, 0.0, 1.0, &dummy, &pos_y);
break;
case FULL_DOWN:
case HALF_DOWN:
page_number_to_position(zathura->document, new_page_id, 0.0, 0.0, &dummy, &pos_y);
break;
}
}
position_set(zathura, pos_x, pos_y);
return false;
}
