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