o pixel values by default. if ( is_numeric( $raw_value ) ) { $raw_value = $raw_value . 'px'; } $defaults = array( 'coerce_to' => '', 'root_size_value' => 16, 'acceptable_units' => array( 'rem', 'px', 'em' ), ); $options = wp_parse_args( $options, $defaults ); $acceptable_units_group = implode( '|', $options['acceptable_units'] ); $pattern = '/^(\d*\.?\d+)(' . $acceptable_units_group . '){1,1}$/'; preg_match( $pattern, $raw_value, $matches ); // Bails out if not a number value and a px or rem unit. if ( ! isset( $matches[1] ) || ! isset( $matches[2] ) ) { return null; } $value = $matches[1]; $unit = $matches[2]; /* * Default browser font size. Later, possibly could inject some JS to * compute this `getComputedStyle( document.querySelector( "html" ) ).fontSize`. */ if ( 'px' === $options['coerce_to'] && ( 'em' === $unit || 'rem' === $unit ) ) { $value = $value * $options['root_size_value']; $unit = $options['coerce_to']; } if ( 'px' === $unit && ( 'em' === $options['coerce_to'] || 'rem' === $options['coerce_to'] ) ) { $value = $value / $options['root_size_value']; $unit = $options['coerce_to']; } /* * No calculation is required if swapping between em and rem yet, * since we assume a root size value. Later we might like to differentiate between * :root font size (rem) and parent element font size (em) relativity. */ if ( ( 'em' === $options['coerce_to'] || 'rem' === $options['coerce_to'] ) && ( 'em' === $unit || 'rem' === $unit ) ) { $unit = $options['coerce_to']; } return array( 'value' => round( $value, 3 ), 'unit' => $unit, ); } /** * Internal implementation of CSS clamp() based on available min/max viewport * width and min/max font sizes. * * @since 6.1.0 * @access private * * @param array $args { * Optional. An associative array of values to calculate a fluid formula * for font size. Default is empty array. * * @type string $maximum_viewport_width Maximum size up to which type will have fluidity. * @type string $minimum_viewport_width Minimum viewport size from which type will have fluidity. * @type string $maximum_font_size Maximum font size for any clamp() calculation. * @type string $minimum_font_size Minimum font size for any clamp() calculation. * @type int $scale_factor A scale factor to determine how fast a font scales within boundaries. * } * @return string|null A font-size value using clamp() on success, otherwise null. */ function wp_get_computed_fluid_typography_value( $args = array() ) { $maximum_viewport_width_raw = isset( $args['maximum_viewport_width'] ) ? $args['maximum_viewport_width'] : null; $minimum_viewport_width_raw = isset( $args['minimum_viewport_width'] ) ? $args['minimum_viewport_width'] : null; $maximum_font_size_raw = isset( $args['maximum_font_size'] ) ? $args['maximum_font_size'] : null; $minimum_font_size_raw = isset( $args['minimum_font_size'] ) ? $args['minimum_font_size'] : null; $scale_factor = isset( $args['scale_factor'] ) ? $args['scale_factor'] : null; // Normalizes the minimum font size in order to use the value for calculations. $minimum_font_size = wp_get_typography_value_and_unit( $minimum_font_size_raw ); /* * We get a 'preferred' unit to keep units consistent when calculating, * otherwise the result will not be accurate. */ $font_size_unit = isset( $minimum_font_size['unit'] ) ? $minimum_font_size['unit'] : 'rem'; // Normalizes the maximum font size in order to use the value for calculations. $maximum_font_size = wp_get_typography_value_and_unit( $maximum_font_size_raw, array( 'coerce_to' => $font_size_unit, ) ); // Checks for mandatory min and max sizes, and protects against unsupported units. if ( ! $maximum_font_size || ! $minimum_font_size ) { return null; } // Uses rem for accessible fluid target font scaling. $minimum_font_size_rem = wp_get_typography_value_and_unit( $minimum_font_size_raw, array( 'coerce_to' => 'rem', ) ); // Viewport widths defined for fluid typography. Normalize units. $maximum_viewport_width = wp_get_typography_value_and_unit( $maximum_viewport_width_raw, array( 'coerce_to' => $font_size_unit, ) ); $minimum_viewport_width = wp_get_typography_value_and_unit( $minimum_viewport_width_raw, array( 'coerce_to' => $font_size_unit, ) ); /* * Build CSS rule. * Borrowed from https://websemantics.uk/tools/responsive-font-calculator/. */ $view_port_width_offset = round( $minimum_viewport_width['value'] / 100, 3 ) . $font_size_unit; $linear_factor = 100 * ( ( $maximum_font_size['value'] - $minimum_font_size['value'] ) / ( $maximum_viewport_width['value'] - $minimum_viewport_width['value'] ) ); $linear_factor_scaled = round( $linear_factor * $scale_factor, 3 ); $linear_factor_scaled = empty( $linear_factor_scaled ) ? 1 : $linear_factor_scaled; $fluid_target_font_size = implode( '', $minimum_font_size_rem ) . " + ((1vw - $view_port_width_offset) * $linear_factor_scaled)"; return "clamp($minimum_font_size_raw, $fluid_target_font_size, $maximum_font_size_raw)"; } /** * 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. * * @since 6.1.0 * @since 6.1.1 Adjusted rules for min and max font sizes. * * @param array $preset { * Required. fontSizes preset value as seen in theme.json. * * @type string $name Name of the font size preset. * @type string $slug Kebab-case, unique identifier for the font size preset. * @type string|int|float $size CSS font-size value, including units if applicable. * } * @param bool $should_use_fluid_typography An override to switch fluid typography "on". Can be used for unit testing. * Default is false. * @return string|null Font-size value or null if a size is not passed in $preset. */ 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. $typography_settings = wp_get_global_settings( array( 'typography' ) ); $should_use_fluid_typography = isset( $typography_settings['fluid'] ) && true === $typography_settings['fluid'] ? true : $should_use_fluid_typography; if ( ! $should_use_fluid_typography ) { return $preset['size']; } // Defaults. $default_maximum_viewport_width = '1600px'; $default_minimum_viewport_width = '768px'; $default_minimum_font_size_factor = 0.75; $default_scale_factor = 1; $default_minimum_font_size_limit = '14px'; // 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( $default_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 ) { $calculated_minimum_font_size = round( $preferred_size['value'] * $default_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' => $default_minimum_viewport_width, 'maximum_viewport_width' => $default_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']; } // Register the block support. WP_Block_Supports::get_instance()->register( 'typography', array( 'register_attribute' => 'wp_register_typography_support', 'apply' => 'wp_apply_typography_support', ) );