project/node_modules/zrender/lib/contain/text.js

171 lines
5.3 KiB
JavaScript

import BoundingRect from '../core/BoundingRect.js';
import LRU from '../core/LRU.js';
import { DEFAULT_FONT, platformApi } from '../core/platform.js';
var textWidthCache = {};
export function getWidth(text, font) {
font = font || DEFAULT_FONT;
var cacheOfFont = textWidthCache[font];
if (!cacheOfFont) {
cacheOfFont = textWidthCache[font] = new LRU(500);
}
var width = cacheOfFont.get(text);
if (width == null) {
width = platformApi.measureText(text, font).width;
cacheOfFont.put(text, width);
}
return width;
}
export function innerGetBoundingRect(text, font, textAlign, textBaseline) {
var width = getWidth(text, font);
var height = getLineHeight(font);
var x = adjustTextX(0, width, textAlign);
var y = adjustTextY(0, height, textBaseline);
var rect = new BoundingRect(x, y, width, height);
return rect;
}
export function getBoundingRect(text, font, textAlign, textBaseline) {
var textLines = ((text || '') + '').split('\n');
var len = textLines.length;
if (len === 1) {
return innerGetBoundingRect(textLines[0], font, textAlign, textBaseline);
}
else {
var uniondRect = new BoundingRect(0, 0, 0, 0);
for (var i = 0; i < textLines.length; i++) {
var rect = innerGetBoundingRect(textLines[i], font, textAlign, textBaseline);
i === 0 ? uniondRect.copy(rect) : uniondRect.union(rect);
}
return uniondRect;
}
}
export function adjustTextX(x, width, textAlign) {
if (textAlign === 'right') {
x -= width;
}
else if (textAlign === 'center') {
x -= width / 2;
}
return x;
}
export function adjustTextY(y, height, verticalAlign) {
if (verticalAlign === 'middle') {
y -= height / 2;
}
else if (verticalAlign === 'bottom') {
y -= height;
}
return y;
}
export function getLineHeight(font) {
return getWidth('国', font);
}
export function measureText(text, font) {
return platformApi.measureText(text, font);
}
export function parsePercent(value, maxValue) {
if (typeof value === 'string') {
if (value.lastIndexOf('%') >= 0) {
return parseFloat(value) / 100 * maxValue;
}
return parseFloat(value);
}
return value;
}
export function calculateTextPosition(out, opts, rect) {
var textPosition = opts.position || 'inside';
var distance = opts.distance != null ? opts.distance : 5;
var height = rect.height;
var width = rect.width;
var halfHeight = height / 2;
var x = rect.x;
var y = rect.y;
var textAlign = 'left';
var textVerticalAlign = 'top';
if (textPosition instanceof Array) {
x += parsePercent(textPosition[0], rect.width);
y += parsePercent(textPosition[1], rect.height);
textAlign = null;
textVerticalAlign = null;
}
else {
switch (textPosition) {
case 'left':
x -= distance;
y += halfHeight;
textAlign = 'right';
textVerticalAlign = 'middle';
break;
case 'right':
x += distance + width;
y += halfHeight;
textVerticalAlign = 'middle';
break;
case 'top':
x += width / 2;
y -= distance;
textAlign = 'center';
textVerticalAlign = 'bottom';
break;
case 'bottom':
x += width / 2;
y += height + distance;
textAlign = 'center';
break;
case 'inside':
x += width / 2;
y += halfHeight;
textAlign = 'center';
textVerticalAlign = 'middle';
break;
case 'insideLeft':
x += distance;
y += halfHeight;
textVerticalAlign = 'middle';
break;
case 'insideRight':
x += width - distance;
y += halfHeight;
textAlign = 'right';
textVerticalAlign = 'middle';
break;
case 'insideTop':
x += width / 2;
y += distance;
textAlign = 'center';
break;
case 'insideBottom':
x += width / 2;
y += height - distance;
textAlign = 'center';
textVerticalAlign = 'bottom';
break;
case 'insideTopLeft':
x += distance;
y += distance;
break;
case 'insideTopRight':
x += width - distance;
y += distance;
textAlign = 'right';
break;
case 'insideBottomLeft':
x += distance;
y += height - distance;
textVerticalAlign = 'bottom';
break;
case 'insideBottomRight':
x += width - distance;
y += height - distance;
textAlign = 'right';
textVerticalAlign = 'bottom';
break;
}
}
out = out || {};
out.x = x;
out.y = y;
out.align = textAlign;
out.verticalAlign = textVerticalAlign;
return out;
}