wp_get_typography_font_size_value() │ WP 6.1.0

Returns a font-size value based on a given font-size preset. Takes into account fluid typography parameters and attempts to return a CSS formula depending on available, valid values.

No Hooks.

Return

String|null. Font-size value or null if a size is not passed in $preset.

Usage

wp_get_typography_font_size_value( $preset, $should_use_fluid_typography );

$preset(array) (required)

Required. fontSizes preset value as seen in theme.json.

• name(string)
  Name of the font size preset.

• slug(string)
  Kebab-case, unique identifier for the font size preset.

• size(string|int|float)
  CSS font-size value, including units if applicable.

$should_use_fluid_typography(true|false)

An override to switch fluid typography "on". Can be used for unit testing.
Default: false

Changelog

wp_get_typography_font_size_value() wp get typography font size value code ^{WP 6.5.2}

function wp_get_typography_font_size_value( $preset, $should_use_fluid_typography = false ) {
	if ( ! isset( $preset['size'] ) ) {
		return null;
	}

	/*
	 * Catches empty values and 0/'0'.
	 * Fluid calculations cannot be performed on 0.
	 */
	if ( empty( $preset['size'] ) ) {
		return $preset['size'];
	}

	// Checks if fluid font sizes are activated.
	$global_settings     = wp_get_global_settings();
	$typography_settings = isset( $global_settings['typography'] ) ? $global_settings['typography'] : array();
	$layout_settings     = isset( $global_settings['layout'] ) ? $global_settings['layout'] : array();

	if (
		isset( $typography_settings['fluid'] ) &&
		( true === $typography_settings['fluid'] || is_array( $typography_settings['fluid'] ) )
	) {
		$should_use_fluid_typography = true;
	}

	if ( ! $should_use_fluid_typography ) {
		return $preset['size'];
	}

	$fluid_settings = isset( $typography_settings['fluid'] ) && is_array( $typography_settings['fluid'] )
		? $typography_settings['fluid']
		: array();

	// Defaults.
	$default_maximum_viewport_width       = '1600px';
	$default_minimum_viewport_width       = '320px';
	$default_minimum_font_size_factor_max = 0.75;
	$default_minimum_font_size_factor_min = 0.25;
	$default_scale_factor                 = 1;
	$default_minimum_font_size_limit      = '14px';

	// Defaults overrides.
	$minimum_viewport_width = isset( $fluid_settings['minViewportWidth'] ) ? $fluid_settings['minViewportWidth'] : $default_minimum_viewport_width;
	$maximum_viewport_width = isset( $layout_settings['wideSize'] ) && ! empty( wp_get_typography_value_and_unit( $layout_settings['wideSize'] ) ) ? $layout_settings['wideSize'] : $default_maximum_viewport_width;
	if ( isset( $fluid_settings['maxViewportWidth'] ) ) {
		$maximum_viewport_width = $fluid_settings['maxViewportWidth'];
	}
	$has_min_font_size       = isset( $fluid_settings['minFontSize'] ) && ! empty( wp_get_typography_value_and_unit( $fluid_settings['minFontSize'] ) );
	$minimum_font_size_limit = $has_min_font_size ? $fluid_settings['minFontSize'] : $default_minimum_font_size_limit;

	// Font sizes.
	$fluid_font_size_settings = isset( $preset['fluid'] ) ? $preset['fluid'] : null;

	// A font size has explicitly bypassed fluid calculations.
	if ( false === $fluid_font_size_settings ) {
		return $preset['size'];
	}

	// Try to grab explicit min and max fluid font sizes.
	$minimum_font_size_raw = isset( $fluid_font_size_settings['min'] ) ? $fluid_font_size_settings['min'] : null;
	$maximum_font_size_raw = isset( $fluid_font_size_settings['max'] ) ? $fluid_font_size_settings['max'] : null;

	// Font sizes.
	$preferred_size = wp_get_typography_value_and_unit( $preset['size'] );

	// Protects against unsupported units.
	if ( empty( $preferred_size['unit'] ) ) {
		return $preset['size'];
	}

	/*
	 * Normalizes the minimum font size limit according to the incoming unit,
	 * in order to perform comparative checks.
	 */
	$minimum_font_size_limit = wp_get_typography_value_and_unit(
		$minimum_font_size_limit,
		array(
			'coerce_to' => $preferred_size['unit'],
		)
	);

	// Don't enforce minimum font size if a font size has explicitly set a min and max value.
	if ( ! empty( $minimum_font_size_limit ) && ( ! $minimum_font_size_raw && ! $maximum_font_size_raw ) ) {
		/*
		 * If a minimum size was not passed to this function
		 * and the user-defined font size is lower than $minimum_font_size_limit,
		 * do not calculate a fluid value.
		 */
		if ( $preferred_size['value'] <= $minimum_font_size_limit['value'] ) {
			return $preset['size'];
		}
	}

	// If no fluid max font size is available use the incoming value.
	if ( ! $maximum_font_size_raw ) {
		$maximum_font_size_raw = $preferred_size['value'] . $preferred_size['unit'];
	}

	/*
	 * If no minimumFontSize is provided, create one using
	 * the given font size multiplied by the min font size scale factor.
	 */
	if ( ! $minimum_font_size_raw ) {
		$preferred_font_size_in_px = 'px' === $preferred_size['unit'] ? $preferred_size['value'] : $preferred_size['value'] * 16;

		/*
		 * The scale factor is a multiplier that affects how quickly the curve will move towards the minimum,
		 * that is, how quickly the size factor reaches 0 given increasing font size values.
		 * For a - b * log2(), lower values of b will make the curve move towards the minimum faster.
		 * The scale factor is constrained between min and max values.
		 */
		$minimum_font_size_factor     = min( max( 1 - 0.075 * log( $preferred_font_size_in_px, 2 ), $default_minimum_font_size_factor_min ), $default_minimum_font_size_factor_max );
		$calculated_minimum_font_size = round( $preferred_size['value'] * $minimum_font_size_factor, 3 );

		// Only use calculated min font size if it's > $minimum_font_size_limit value.
		if ( ! empty( $minimum_font_size_limit ) && $calculated_minimum_font_size <= $minimum_font_size_limit['value'] ) {
			$minimum_font_size_raw = $minimum_font_size_limit['value'] . $minimum_font_size_limit['unit'];
		} else {
			$minimum_font_size_raw = $calculated_minimum_font_size . $preferred_size['unit'];
		}
	}

	$fluid_font_size_value = wp_get_computed_fluid_typography_value(
		array(
			'minimum_viewport_width' => $minimum_viewport_width,
			'maximum_viewport_width' => $maximum_viewport_width,
			'minimum_font_size'      => $minimum_font_size_raw,
			'maximum_font_size'      => $maximum_font_size_raw,
			'scale_factor'           => $default_scale_factor,
		)
	);

	if ( ! empty( $fluid_font_size_value ) ) {
		return $fluid_font_size_value;
	}

	return $preset['size'];
}