function close(x, y, message) {
ok(Math.abs(x - y) < 1e-4, message);
}
function runTest() { var text = document.querySelector("text");
// get the original length var length = text.getComputedTextLength();
// get the original glyph positions var startPositions = [],
endPositions = [],
extents = [];
for (let i = 0; i < 3; i++) {
startPositions.push(text.getStartPositionOfChar(i));
endPositions.push(text.getEndPositionOfChar(i));
extents.push(text.getExtentOfChar(i));
}
// widths should all be the same
is(extents[0].width, extents[1].width);
is(extents[0].width, extents[2].width);
var checkCharNumAtPosition = function(x, y, i) { var p = document.querySelector("svg").createSVGPoint();
p.x = x;
p.y = y;
is(text.getCharNumAtPosition(p), i, "getCharNumAtPosition(" + i + ")");
};
var checkPositions = function(start, end, width) {
for (let i = 0; i < 3; i++) {
// check their positions
close(text.getStartPositionOfChar(i).x, start[i], "start position of glyph " + i);
close(text.getEndPositionOfChar(i).x, end[i], "end position of glyph " + i);
close(text.getExtentOfChar(i).x, start[i], "left edge of extent of glyph " + i);
close(text.getExtentOfChar(i).width, width, "width of glyph " + i);
checkCharNumAtPosition((start[i] + end[i]) / 2, 100, i);
}
};
var w = extents[0].width;
var doLengthAdjustSpacingTest = function() {
// getComputedTextLength should return the sum of the advances, and since
// we are just changing the positions of the glyphs, it should be the same
// as without a textLength="" attribute
close(text.getComputedTextLength(), length, "getComputedTextLength when lengthAdjust=\"spacing\"");
// expected start and end positions of the glyphs var start = [0, 50 - w / 2, 100 - w]; var end = [w, 50 + w / 2, 100];
checkPositions(start, end, w);
};
// switch to adjust glyph positions, using the default value of lengthAdjust=""
text.setAttribute("textLength", "100");
doLengthAdjustSpacingTest();
// then with an explicit lengthAdjust="spacing"
text.setAttribute("lengthAdjust", "spacing");
doLengthAdjustSpacingTest();
// now test with lengthAdjust="spacingAndGlyphs"
text.setAttribute("lengthAdjust", "spacingAndGlyphs");
// now that each glyph is stretched, the total advance should be the textLength
close(text.getComputedTextLength(), 100, "getComputedTextLength when lengthAdjust=\"spacingAndGlyphs\"");
// expected start and end positions of the glyphs var start = [0, 33.3333, 66.6666]; var end = [33.3333, 66.6666, 100];
checkPositions(start, end, 33.3333);
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