Commit 6db1bbd9 authored by violet's avatar violet
Browse files

Bug 1370646 - Honor the maxTextRunSize if it's within reasonable range r=heycam 

If the maximal and minimal font-size in a SVGTextFrame have a huge difference,
previously we chose mFontSizeScaleFactor to satisfy the minimal one. That's
problematic, because the maximal one might be a reasonable size, while the minimal
one is extremely small. We should honor the maximal one if this is the case.

Differential Revision: https://phabricator.services.mozilla.com/D24494

--HG--
extra : moz-landing-system : lando
parent 177f4b29

layout/svg/SVGTextFrame.cpp

+14 −3
Original line number Diff line number Diff line
@@ -5222,9 +5222,20 @@ bool SVGTextFrame::UpdateFontSizeScaleFactor() { 
    mFontSizeScaleFactor = contextScale;

  } else if (maxSize / minSize > CLAMP_MAX_SIZE / CLAMP_MIN_SIZE) {

    // We can't scale the font sizes so that all of the text frames lie

    // within our ideal font size range, so we treat the minimum as more

    // important and just scale so that minSize = CLAMP_MIN_SIZE.

    // within our ideal font size range.

    // Heuristically, if the maxTextRunSize is within the CLAMP_MAX_SIZE

    // as a reasonable value, it's likely to be the user's intent to

    // get a valid font for the maxTextRunSize one, we should honor it.

    // The same for minTextRunSize.

    if (maxTextRunSize <= CLAMP_MAX_SIZE) {

      mFontSizeScaleFactor = CLAMP_MAX_SIZE / maxSize;

    } else if (minTextRunSize >= CLAMP_MIN_SIZE) {

      mFontSizeScaleFactor = CLAMP_MIN_SIZE / minSize;

    } else {

      // So maxTextRunSize is too big, minTextRunSize is too small,

      // we can't really do anything for this case, just leave it as is.

      mFontSizeScaleFactor = contextScale;

    }

  } else if (minTextRunSize < CLAMP_MIN_SIZE) {

    mFontSizeScaleFactor = CLAMP_MIN_SIZE / minSize;

  } else {

layout/svg/tests/mochitest.ini

+1 −0
Original line number Diff line number Diff line
@@ -11,4 +11,5 @@ support-files = 
  file_yellow_black.svg



[test_hover_near_text.html]

[test_multiple_font_size.html]

[test_use_tree_cycle.html]

layout/svg/tests/test_multiple_font_size.html

0 → 100644
+26 −0
Original line number Diff line number Diff line 
<!DOCTYPE HTML>

<script src="/tests/SimpleTest/SimpleTest.js"></script>

<link rel="stylesheet" href="/tests/SimpleTest/test.css">

<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1370646">Mozilla Bug 1370646</a>



<svg xmlns="http://www.w3.org/2000/svg" width="440" height="100" viewBox="0 0 440 100">

  <text>

    <tspan id="a" style="font-size:100px">3</tspan>

  </text>

  <text>

    <tspan id="b" style="font-size:100px">3</tspan>

    <tspan style="font-size:0.1px">0</tspan>

  </text>

</svg>



<script type="application/javascript">

  SimpleTest.waitForExplicitFinish();



  let alen = document.getElementById("a").getComputedTextLength(),

      blen = document.getElementById("b").getComputedTextLength();



  SimpleTest.isfuzzy(alen, blen, 5, "lengths should be close");



  SimpleTest.finish();

</script>