Merge pull request #9536 from ahocevar/font-cache-hits

More font cache hits
openlayers · May 15, 2019 · 11607ca · 11607ca
2 parents 39de245 + 41e958e
commit 11607ca
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Showing 2 changed files with 14 additions and 30 deletions.
diff --git a/src/ol/geom/flat/textpath.js b/src/ol/geom/flat/textpath.js
@@ -16,8 +16,8 @@ import {lerp} from '../../math.js';
  * @param {function(string, string, Object<string, number>):number} measureAndCacheTextWidth Measure and cache text width.
  * @param {string} font The font.
  * @param {Object<string, number>} cache A cache of measured widths.
- * @return {Array<Array<*>>} The result array of null if `maxAngle` was
- * exceeded. Entries of the array are x, y, anchorX, angle, chunk.
+ * @return {Array<Array<*>>} The result array (or null if `maxAngle` was
+ * exceeded). Entries of the array are x, y, anchorX, angle, chunk.
  */
 export function drawTextOnPath(
   flatCoordinates, offset, end, stride, text, startM, maxAngle, scale, measureAndCacheTextWidth, font, cache) {
@@ -35,16 +35,13 @@ export function drawTextOnPath(
   let y2 = flatCoordinates[offset + 1];
   let segmentM = 0;
   let segmentLength = Math.sqrt(Math.pow(x2 - x1, 2) + Math.pow(y2 - y1, 2));
+  let angleChanged = false;
 
-  let chunk = '';
-  let chunkLength = 0;
-  let data, index, previousAngle;
+  let index, previousAngle;
   for (let i = 0; i < numChars; ++i) {
     index = reverse ? numChars - i - 1 : i;
-    const char = text.charAt(index);
-    chunk = reverse ? char + chunk : chunk + char;
-    const charLength = scale * measureAndCacheTextWidth(font, chunk, cache) - chunkLength;
-    chunkLength += charLength;
+    const char = text[index];
+    const charLength = scale * measureAndCacheTextWidth(font, char, cache);
     const charM = startM + charLength / 2;
     while (offset < end - stride && segmentM + segmentLength < charM) {
       x1 = x2;
@@ -62,33 +59,18 @@ export function drawTextOnPath(
     }
     if (previousAngle !== undefined) {
       let delta = angle - previousAngle;
+      angleChanged = angleChanged || delta !== 0;
       delta += (delta > Math.PI) ? -2 * Math.PI : (delta < -Math.PI) ? 2 * Math.PI : 0;
       if (Math.abs(delta) > maxAngle) {
         return null;
       }
     }
+    previousAngle = angle;
     const interpolate = segmentPos / segmentLength;
     const x = lerp(x1, x2, interpolate);
     const y = lerp(y1, y2, interpolate);
-    if (previousAngle == angle) {
-      if (reverse) {
-        data[0] = x;
-        data[1] = y;
-        data[2] = charLength / 2;
-      }
-      data[4] = chunk;
-    } else {
-      chunk = char;
-      chunkLength = charLength;
-      data = [x, y, charLength / 2, angle, chunk];
-      if (reverse) {
-        result.unshift(data);
-      } else {
-        result.push(data);
-      }
-      previousAngle = angle;
-    }
+    result[index] = [x, y, charLength / 2, angle, char];
     startM += charLength;
   }
-  return result;
+  return angleChanged ? result : [[result[0][0], result[0][1], result[0][2], result[0][3], text]];
 }
diff --git a/test/spec/ol/geom/flat/textpath.test.js b/test/spec/ol/geom/flat/textpath.test.js
@@ -72,9 +72,11 @@ describe('ol.geom.flat.drawTextOnPath', function() {
     const instructions = drawTextOnPath(
       angled, 0, angled.length, 2, 'foo', startM, Infinity, 1, measureAndCacheTextWidth, '', {});
     expect(instructions[0][3]).to.eql(45 * Math.PI / 180);
-    expect(instructions[0][4]).to.be('fo');
-    expect(instructions[1][3]).to.eql(-45 * Math.PI / 180);
+    expect(instructions[0][4]).to.be('f');
+    expect(instructions[1][3]).to.eql(45 * Math.PI / 180);
     expect(instructions[1][4]).to.be('o');
+    expect(instructions[2][3]).to.eql(-45 * Math.PI / 180);
+    expect(instructions[2][4]).to.be('o');
   });
 
   it('respects maxAngle', function() {