GtDrawingRange gt_coords_calc_generic_range(GtRange node_range,
GtRange viewrange)
{
GtDrawingRange converted_range;
converted_range.clip = CLIPPED_NONE;
node_range.end++;
/* scale coordinates to target image width */
if (node_range.start < viewrange.start )
converted_range.clip = CLIPPED_LEFT;
converted_range.start = gt_coords_convert_point(viewrange, node_range.start);
if (node_range.end > viewrange.end+1)
converted_range.clip = (converted_range.clip == CLIPPED_LEFT ?
CLIPPED_BOTH :
CLIPPED_RIGHT);
converted_range.end = gt_coords_convert_point(viewrange, node_range.end);
return converted_range;
}
/* Renders a ruler with dynamic scale labeling and optional grid. */
int gt_canvas_cairo_draw_ruler(GtCanvas *canvas, GtRange viewrange,
GtError *err)
{
double step, minorstep, vmajor, vminor,
theight = gt_graphics_get_text_height(canvas->pvt->g);
long base_length, tick;
GtColor rulercol, gridcol;
GtStr *left_str, *right_str, *unit;
char str[BUFSIZ];
GtStyleQueryStatus rval;
bool showgrid = true;
gt_assert(canvas);
if (gt_style_get_bool(canvas->pvt->sty, "format", "show_grid", &showgrid,
NULL, err) == GT_STYLE_QUERY_ERROR) {
return -1;
}
if (gt_style_get_num(canvas->pvt->sty, "format", "ruler_font_size",
&theight, NULL, err) == GT_STYLE_QUERY_ERROR) {
return -1;
}
/* get unit value from style, default: empty */
unit = gt_str_new();
if (gt_style_get_str(canvas->pvt->sty,
"format", "unit",
unit, NULL, err) == GT_STYLE_QUERY_ERROR) {
gt_str_delete(unit);
return -1;
}
/* get additional description texts from style */
left_str = gt_str_new();
rval = gt_style_get_str(canvas->pvt->sty, "format",
"ruler_left_text", left_str, NULL, err);
switch (rval) {
case GT_STYLE_QUERY_NOT_SET:
gt_str_append_cstr(left_str, FIVE_PRIME_STRING);
break;
case GT_STYLE_QUERY_ERROR:
gt_str_delete(unit);
gt_str_delete(left_str);
return -1;
break; /* shouldn't reach this */
default:
break;
}
right_str = gt_str_new();
rval = gt_style_get_str(canvas->pvt->sty, "format",
"ruler_right_text", right_str, NULL, err);
switch (rval) {
case GT_STYLE_QUERY_NOT_SET:
gt_str_append_cstr(right_str, THREE_PRIME_STRING);
break;
case GT_STYLE_QUERY_ERROR:
gt_str_delete(unit);
gt_str_delete(left_str);
gt_str_delete(right_str);
return -1;
break; /* shouldn't reach this */
default:
break;
}
/* reset font to default */
gt_graphics_set_font(canvas->pvt->g,
"Sans",
SLANT_NORMAL,
WEIGHT_NORMAL,
theight);
rulercol.red = rulercol.green = rulercol.blue = RULER_GREY;
rulercol.alpha = 1.0;
gridcol.red = gridcol.green = gridcol.blue = GRID_GREY;
gridcol.alpha = 1.0;
/* determine range and step of the scale */
base_length = gt_range_length(&viewrange);
/* determine tick steps */
step = pow(10,ceil(log10(base_length))-1);
minorstep = step/10.0;
/* calculate starting positions */
vminor = (double) (floor(viewrange.start / minorstep))*minorstep;
vmajor = (double) (floor(viewrange.start / step))*step;
/* draw major ticks */
for (tick = vmajor; tick <= viewrange.end; tick += step)
{
double drawtick = (gt_coords_convert_point(viewrange, tick)
* (canvas->pvt->width-2*canvas->pvt->margins))
+ canvas->pvt->margins;
if (tick < viewrange.start) continue;
gt_graphics_draw_vertical_line(canvas->pvt->g,
drawtick,
canvas->pvt->y + 30,
rulercol,
10,
1.0);
gt_format_ruler_label(str, tick, gt_str_get(unit), BUFSIZ);
gt_graphics_draw_text_centered(canvas->pvt->g,
drawtick,
canvas->pvt->y + 20,
str);
}
/* draw minor ticks */
if (minorstep >= 1)
{
for (tick = vminor; tick <= viewrange.end; tick += minorstep)
{
double drawtick;
if (tick < viewrange.start)
continue;
drawtick = (gt_coords_convert_point(viewrange, tick)
* (canvas->pvt->width-2*canvas->pvt->margins))
+ canvas->pvt->margins;
if (showgrid)
{
gt_graphics_draw_vertical_line(canvas->pvt->g,
drawtick,
canvas->pvt->y + 40,
gridcol,
canvas->pvt->height - 40 - 15,
1.0);
}
gt_graphics_draw_vertical_line(canvas->pvt->g,
drawtick,
canvas->pvt->y + 35,
rulercol,
5,
1.0);
}
}
/* draw ruler line */
gt_graphics_draw_horizontal_line(canvas->pvt->g,
canvas->pvt->margins,
canvas->pvt->y + 40,
rulercol,
canvas->pvt->width - 2
* canvas->pvt->margins,
1.25);
gt_graphics_draw_text_right(canvas->pvt->g,
canvas->pvt->margins - 10,
canvas->pvt->y + 39 + (theight/2),
gt_str_get(left_str));
gt_graphics_draw_text(canvas->pvt->g,
canvas->pvt->width - canvas->pvt->margins + 10,
canvas->pvt->y + 39 + (theight/2),
gt_str_get(right_str));
gt_str_delete(unit);
gt_str_delete(left_str);
gt_str_delete(right_str);
return 0;
}
