/* exported function documented in render/font_internal.h */
void font_plot_style_from_css(const css_computed_style *css,
plot_font_style_t *fstyle)
{
lwc_string **families;
css_fixed length = 0;
css_unit unit = CSS_UNIT_PX;
css_color col;
fstyle->family = plot_font_generic_family(
css_computed_font_family(css, &families));
css_computed_font_size(css, &length, &unit);
fstyle->size = FIXTOINT(FMUL(nscss_len2pt(length, unit),
INTTOFIX(FONT_SIZE_SCALE)));
/* Clamp font size to configured minimum */
if (fstyle->size < (nsoption_int(font_min_size) * FONT_SIZE_SCALE) / 10)
fstyle->size = (nsoption_int(font_min_size) * FONT_SIZE_SCALE) / 10;
fstyle->weight = plot_font_weight(css_computed_font_weight(css));
fstyle->flags = plot_font_flags(css_computed_font_style(css),
css_computed_font_variant(css));
css_computed_color(css, &col);
fstyle->foreground = nscss_color_to_ns(col);
fstyle->background = 0;
}
/**
* Convert a CSS length to pixels.
*
* \param length Length to convert
* \param unit Corresponding unit
* \param style Computed style applying to length. May be NULL if unit is
* neither em nor ex
* \return length in pixels
*/
css_fixed nscss_len2px(css_fixed length, css_unit unit,
const css_computed_style *style)
{
/* We assume the screen and ay other output has the same dpi */
css_fixed px_per_unit;
assert(style != NULL || (unit != CSS_UNIT_EM && unit != CSS_UNIT_EX));
switch (unit) {
case CSS_UNIT_EM:
case CSS_UNIT_EX:
{
css_fixed font_size = 0;
css_unit font_unit = CSS_UNIT_PT;
css_computed_font_size(style, &font_size, &font_unit);
/* Convert to points */
font_size = nscss_len2pt(font_size, font_unit);
/* Clamp to configured minimum */
if (font_size < FDIV(INTTOFIX(nsoption_int(font_min_size)), F_10)) {
font_size = FDIV(INTTOFIX(nsoption_int(font_min_size)), F_10);
}
/* Convert to pixels (manually, to maximise precision)
* 1in = 72pt => 1pt = (DPI/72)px */
px_per_unit = FDIV(FMUL(font_size, nscss_screen_dpi), F_72);
/* Scale ex units: we use a fixed ratio of 1ex = 0.6em */
if (unit == CSS_UNIT_EX)
px_per_unit = FMUL(px_per_unit, FLTTOFIX(0.6));
}
break;
case CSS_UNIT_PX:
px_per_unit = F_1;
break;
/* 1in = DPIpx */
case CSS_UNIT_IN:
px_per_unit = nscss_screen_dpi;
break;
/* 1in = 2.54cm => 1cm = (DPI/2.54)px */
case CSS_UNIT_CM:
px_per_unit = FDIV(nscss_screen_dpi, FLTTOFIX(2.54));
break;
/* 1in = 25.4mm => 1mm = (DPI/25.4)px */
case CSS_UNIT_MM:
px_per_unit = FDIV(nscss_screen_dpi, FLTTOFIX(25.4));
break;
/* 1in = 72pt => 1pt = (DPI/72)px */
case CSS_UNIT_PT:
px_per_unit = FDIV(nscss_screen_dpi, F_72);
break;
/* 1pc = 12pt => 1in = 6pc => 1pc = (DPI/6)px */
case CSS_UNIT_PC:
px_per_unit = FDIV(nscss_screen_dpi, INTTOFIX(6));
break;
default:
px_per_unit = 0;
break;
}
/* Ensure we round px_per_unit to the nearest whole number of pixels:
* the use of FIXTOINT() below will truncate. */
px_per_unit += F_0_5;
/* Calculate total number of pixels */
return FMUL(length, TRUNCATEFIX(px_per_unit));
}
