ashatora/openlayers
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Don't iterate each chracter if entire string fits in single segment

Browse Source
This commit is contained in:
Maximilian Krög
2020-09-25 21:13:05 +02:00
parent 7660f3c522
commit 528833b05b
1 changed files with 21 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
src/ol/geom/flat/textpath.js
View File

@@ -60,7 +60,7 @@ export function drawTextOnPath(
const startOffset = offset - stride;
const startLength = segmentM;
const endM = startM + measureAndCacheTextWidth(font, text, cache);
const endM = startM + scale * measureAndCacheTextWidth(font, text, cache);
while (offset < end - stride && segmentM + segmentLength < endM) {
advance();
}
@@ -78,13 +78,14 @@ export function drawTextOnPath(
reverse = beginX > endX;
}
const singleSegment = startOffset + stride === offset;
offset = startOffset;
segmentLength = 0;
segmentM = startLength;
x2 = flatCoordinates[offset];
y2 = flatCoordinates[offset + 1];
advance();
let angleChanged = false;
const PI = Math.PI;
const result = [];
@@ -92,24 +93,33 @@ export function drawTextOnPath(
if (reverse) {
previousAngle += previousAngle > 0 ? -PI : PI;
}
// All on the same segment
if (singleSegment) {
const x = (endX + beginX) / 2;
const y = (endY + beginY) / 2;
result[0] = [x, y, (endM - startM) / 2, previousAngle, text];
return result;
}
for (let i = 0, ii = text.length; i < ii; ++i) {
const index = reverse ? ii - i - 1 : i;
const char = text[index];
const charLength = scale * measureAndCacheTextWidth(font, char, cache);
const charM = startM + charLength / 2;
let angle;
while (offset < end - stride && segmentM + segmentLength < charM) {
advance();
let angle = Math.atan2(y2 - y1, x2 - x1);
angle = Math.atan2(y2 - y1, x2 - x1);
if (reverse) {
angle += angle > 0 ? -PI : PI;
}
if (previousAngle !== undefined && angle !== previousAngle) {
let delta = angle - previousAngle;
delta += delta > PI ? -2 * PI : delta < -PI ? 2 * PI : 0;
if (Math.abs(delta) > maxAngle) {
return null;
}
angleChanged = true;
}
if (angle !== undefined) {
let delta = angle - previousAngle;
delta += delta > PI ? -2 * PI : delta < -PI ? 2 * PI : 0;
if (Math.abs(delta) > maxAngle) {
return null;
}
previousAngle = angle;
}
@@ -119,7 +129,5 @@ export function drawTextOnPath(
result[index] = [x, y, charLength / 2, previousAngle, char];
startM += charLength;
}
return angleChanged
? result
: [[result[0][0], result[0][1], result[0][2], result[0][3], text]];
return result;
}