* This function is a convenience function for looking up information in the * metricMap table. It takes a character as a string, and a font. * * Note: the `width` property may be undefined if fontMetricsData.js wasn't * built using `Make extended_metrics`.
(character, font, mode)
| 3741 | */ |
| 3742 | |
| 3743 | function getCharacterMetrics(character, font, mode) { |
| 3744 | if (!metricMap[font]) { |
| 3745 | throw new Error(`Font metrics not found for font: ${font}.`); |
| 3746 | } |
| 3747 | |
| 3748 | let ch = character.charCodeAt(0); |
| 3749 | |
| 3750 | if (character[0] in extraCharacterMap) { |
| 3751 | ch = extraCharacterMap[character[0]].charCodeAt(0); |
| 3752 | } |
| 3753 | |
| 3754 | let metrics = metricMap[font][ch]; |
| 3755 | |
| 3756 | if (!metrics && mode === 'text') { |
| 3757 | // We don't typically have font metrics for Asian scripts. |
| 3758 | // But since we support them in text mode, we need to return |
| 3759 | // some sort of metrics. |
| 3760 | // So if the character is in a script we support but we |
| 3761 | // don't have metrics for it, just use the metrics for |
| 3762 | // the Latin capital letter M. This is close enough because |
| 3763 | // we (currently) only care about the height of the glpyh |
| 3764 | // not its width. |
| 3765 | if (supportedCodepoint(ch)) { |
| 3766 | metrics = metricMap[font][77]; // 77 is the charcode for 'M' |
| 3767 | } |
| 3768 | } |
| 3769 | |
| 3770 | if (metrics) { |
| 3771 | return { |
| 3772 | depth: metrics[0], |
| 3773 | height: metrics[1], |
| 3774 | italic: metrics[2], |
| 3775 | skew: metrics[3], |
| 3776 | width: metrics[4] |
| 3777 | }; |
| 3778 | } |
| 3779 | } |
| 3780 | const fontMetricsBySizeIndex = {}; |
| 3781 | /** |
| 3782 | * Get the font metrics for a given size. |
no test coverage detected