joepie91
/
canvassed-text
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Refactor text layouting code

Browse Source
master
Sven Slootweg 7 years ago
parent 17909f2ed1
commit 72845b03c8
2 changed files with 102 additions and 146 deletions
Show Stats Download Patch File Download Diff File

7
src/layout/adjust-line-heights.js
Unescape Escape View File

@ -1,7 +0,0 @@
'use strict';
module.exports = function adjustLineHeights(lines, lineHeight) {
return lines.map((line, i) => {
return line.height * lineHeight * 1.13;
});
};

241
src/layout/index.js
Unescape Escape View File

@ -12,8 +12,6 @@ const max = require("../util/max");
const last = require("../util/last");
function drawDebugLine(context, lineNumber, y, width, color = "red") {
//context.globalAlpha = 1;
context.strokeStyle = color;
context.beginPath();
@ -35,164 +33,129 @@ function drawDebugLine(context, lineNumber, y, width, color = "red") {
context.font = "12px sans-serif";
context.fillStyle = "white";
context.fillText(lineNumber, 5 + boxOffset * 18, y + 15)
context.fillText(lineNumber, 5 + boxOffset * 18, y + 15);
}
function layoutItems(lines, options = {}) {
let currentYOffset = options.initialY;
let currentXOffset = 0;
let debugYOffset = 0;
let debugLines = [];
let positionedItems = lines.reduce((items, line, i) => {
debugLines.push({color: "red", y: debugYOffset, lineNumber: i});
debugLines.push({color: "green", y: currentYOffset, lineNumber: i});
debugLines.push({color: "orange", y: currentYOffset + line.adjustedHeight, lineNumber: i});
let newItems = items.concat(line.items.map((item) => {
let x = currentXOffset;
let y = currentYOffset - (line.minAscender / 2) + (line.adjustedHeight / 2)
debugLines.push({color: "blue", y: y, x1: x, x2: x + item.measurements.width, lineNumber: i});
currentXOffset += item.measurements.width;
return Object.assign({
x: x,
y: y
}, item);
}));
currentYOffset += line.adjustedHeight;
debugYOffset += line.adjustedHeight;
currentXOffset = 0;
return newItems;
}, []);
//context.globalAlpha = 1;
return {
positionedItems: positionedItems,
debugLines: debugLines
}
}
module.exports = function layoutFormattedText(text, options) {
if (options.tags === true) {
let lines = parser(text).map((lineItems) => {
let measuredItems = lineItems.filter(item => item.text !== "").map((item) => {
let generatedStyle = generateStyle(item, {
classes: options.classes,
defaultStyle: options.defaultStyle
});
return Object.assign({
measurements: measureText(item.text, generatedStyle),
style: generatedStyle
}, item);
});
let lines;
if (measuredItems.length > 0) {
return {
alignment: (lineItems.length > 0) ? findAlignment(lineItems[0]) : null,
items: measuredItems,
height: max(measuredItems.map(item => item.measurements.height)),
width: sum(measuredItems.map(item => item.measurements.width)),
minAscender: min(measuredItems.map(item => item.measurements.ascender)),
maxDescender: max(measuredItems.map(item => item.measurements.descender))
}
} else {
/* This line does not contain any real elements, so we'll omit it. */
return null;
}
}).filter(line => line != null);
let adjustedLineHeights = adjustLineHeights(lines, options.lineHeight);
/* We start out by moving everything up half the first line's height - this
* compensates for the middle-of-the-line-oriented line spacing of the first
* line. Otherwise, everything would be shifted off the canvas.*/
let startHeightCorrection, endHeightCorrection;
if (options.trimVerticalWhitespace) {
startHeightCorrection = -(adjustedLineHeights[0] / 2) - (lines[0].minAscender / 2);
endHeightCorrection = -(last(adjustedLineHeights) / 2) - (last(lines).minAscender / 2);
} else {
startHeightCorrection = 0;
endHeightCorrection = 0;
}
let currentLineOffset = startHeightCorrection;
let debugLineOffset = 0;
let currentComponentOffset = 0;
let debugLines = [];
let positionedItems = lines.reduce((items, line, i) => {
debugLines.push({color: "red", y: debugLineOffset, lineNumber: i});
debugLines.push({color: "green", y: currentLineOffset, lineNumber: i});
debugLines.push({color: "orange", y: currentLineOffset + adjustedLineHeights[i], lineNumber: i});
let newItems = items.concat(line.items.map((item) => {
let positionedItem = Object.assign({
x: currentComponentOffset,
y: currentLineOffset - (line.minAscender / 2) + (adjustedLineHeights[i] / 2)
}, item);
debugLines.push({color: "blue", y: positionedItem.y, x1: positionedItem.x, x2: positionedItem.x + item.measurements.width, lineNumber: i});
currentComponentOffset += item.measurements.width;
return positionedItem;
}));
currentLineOffset += adjustedLineHeights[i];
debugLineOffset += adjustedLineHeights[i];
currentComponentOffset = 0;
return newItems;
}, []);
return {
width: Math.ceil(max(lines.map(line => line.width))),
height: Math.ceil(sum(adjustedLineHeights) + startHeightCorrection + endHeightCorrection + (last(lines).maxDescender)),
items: positionedItems,
drawDebugLines: function drawDebugLines(context) {
debugLines.forEach((debugLine) => {
let width;
if (debugLine.x1 != null) {
width = [debugLine.x1, debugLine.x2];
} else {
width = this.width;
}
drawDebugLine(context, debugLine.lineNumber, debugLine.y, width, debugLine.color);
});
}
}
if (options.tags === true) {
lines = parser(text).map((lineItems) => {
return {
items: lineItems
};
});
} else {
let debugLines = [];
lines = text.split("\n").map((line) => {
let lineMeasurements = measureText(line, options.defaultStyle);
let lines = text.split("\n").map((line) => {
return {
text: line,
measurements: measureText(line, options.defaultStyle)
items: [{
text: line
}]
};
});
}
let adjustedLineHeights = adjustLineHeights(lines.map((line) => {
return {
text: line.text,
height: line.measurements.height
let processedLines = lines.map((line) => {
let processedItems = line.items.map((item) => {
let style;
if (item.tags != null) {
style = Object.assign({}, options.defaultStyle, generateStyle(item.tags, options.classes));
} else {
style = options.defaultStyle;
}
}), options.lineHeight);
let startHeightCorrection, endHeightCorrection;
return Object.assign(item, {
style: style,
measurements: measureText(item.text, style)
});
});
if (options.trimVerticalWhitespace) {
startHeightCorrection = -(adjustedLineHeights[0] / 2) - (lines[0].measurements.ascender / 2);
endHeightCorrection = -(last(adjustedLineHeights) / 2) - (last(lines).measurements.ascender / 2);
} else {
startHeightCorrection = 0;
endHeightCorrection = 0;
}
let height = max(processedItems.map(item => item.measurements.height));
let currentLineOffset = startHeightCorrection;
return Object.assign(line, {
alignment: (line.items.length > 0) ? findAlignment(line.items[0]) : null,
items: processedItems,
height: height,
adjustedHeight: height * options.lineHeight * 1.13,
width: sum(processedItems.map(item => item.measurements.width)),
minAscender: min(processedItems.map(item => item.measurements.ascender)),
maxDescender: max(processedItems.map(item => item.measurements.descender))
});
});
let debugLineOffset = 0;
let startHeightCorrection, endHeightCorrection;
let positionedItems = lines.map((line, i) => {
let newItem = {
text: line.text,
measurements: line.measurements,
style: options.defaultStyle,
x: 0,
y: currentLineOffset - (line.measurements.ascender / 2) + (adjustedLineHeights[i] / 2)
}
if (options.trimVerticalWhitespace) {
startHeightCorrection = -(lines[0].adjustedHeight / 2) - (lines[0].minAscender / 2);
endHeightCorrection = -(last(lines).adjustedHeight / 2) - (last(lines).minAscender / 2);
} else {
startHeightCorrection = 0;
endHeightCorrection = 0;
}
debugLines.push({color: "red", y: debugLineOffset, lineNumber: i});
debugLines.push({color: "green", y: currentLineOffset, lineNumber: i});
debugLines.push({color: "blue", y: newItem.y, lineNumber: i});
debugLines.push({color: "orange", y: currentLineOffset + adjustedLineHeights[i], lineNumber: i});
let {positionedItems, debugLines} = layoutItems(lines, {
initialY: startHeightCorrection
});
currentLineOffset += adjustedLineHeights[i];
debugLineOffset += adjustedLineHeights[i];
let combinedLineHeights = sum(lines.map(line => line.adjustedHeight));
return newItem;
});
return {
width: Math.ceil(max(lines.map(line => line.width))),
height: Math.ceil(combinedLineHeights + startHeightCorrection + endHeightCorrection + last(lines).maxDescender),
items: positionedItems,
drawDebugLines: function drawDebugLines(context) {
debugLines.forEach((debugLine) => {
let width;
return {
width: Math.ceil(max(lines.map(line => line.measurements.width))),
height: Math.ceil(sum(adjustedLineHeights) + startHeightCorrection + endHeightCorrection + (last(lines).measurements.descender)),
items: positionedItems,
drawDebugLines: function drawDebugLines(context) {
debugLines.forEach((debugLine) => {
drawDebugLine(context, debugLine.lineNumber, debugLine.y, this.width, debugLine.color);
});
}
if (debugLine.x1 != null) {
width = [debugLine.x1, debugLine.x2];
} else {
width = this.width;
}
drawDebugLine(context, debugLine.lineNumber, debugLine.y, width, debugLine.color);
});
}
}
};

Write Preview
Loading…
Cancel
Save