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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /dom/svg/SVGLength.cpp
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'dom/svg/SVGLength.cpp')
-rw-r--r--dom/svg/SVGLength.cpp255
1 files changed, 255 insertions, 0 deletions
diff --git a/dom/svg/SVGLength.cpp b/dom/svg/SVGLength.cpp
new file mode 100644
index 0000000000..7a0bbf6437
--- /dev/null
+++ b/dom/svg/SVGLength.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "SVGLength.h"
+
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/dom/SVGElement.h"
+#include "mozilla/dom/SVGSVGElement.h"
+#include "nsTextFormatter.h"
+#include "SVGContentUtils.h"
+#include <limits>
+#include <algorithm>
+
+using namespace mozilla::dom;
+using namespace mozilla::dom::SVGLength_Binding;
+
+namespace mozilla {
+
+void SVGLength::GetValueAsString(nsAString& aValue) const {
+ nsTextFormatter::ssprintf(aValue, u"%g", (double)mValue);
+
+ nsAutoString unitString;
+ GetUnitString(unitString, mUnit);
+ aValue.Append(unitString);
+}
+
+bool SVGLength::SetValueFromString(const nsAString& aString) {
+ bool success;
+ auto token = SVGContentUtils::GetAndEnsureOneToken(aString, success);
+
+ if (!success) {
+ return false;
+ }
+
+ RangedPtr<const char16_t> iter = SVGContentUtils::GetStartRangedPtr(token);
+ const RangedPtr<const char16_t> end = SVGContentUtils::GetEndRangedPtr(token);
+
+ float value;
+
+ if (!SVGContentUtils::ParseNumber(iter, end, value)) {
+ return false;
+ }
+
+ const nsAString& units = Substring(iter.get(), end.get());
+ uint16_t unitType = GetUnitTypeForString(units);
+ if (unitType == SVG_LENGTHTYPE_UNKNOWN) {
+ return false;
+ }
+ mValue = value;
+ mUnit = uint8_t(unitType);
+ return true;
+}
+
+inline static bool IsAbsoluteUnit(uint8_t aUnit) {
+ return aUnit >= SVGLength_Binding::SVG_LENGTHTYPE_CM &&
+ aUnit <= SVGLength_Binding::SVG_LENGTHTYPE_PC;
+}
+
+/**
+ * Helper to convert between different CSS absolute units without the need for
+ * an element, which provides more flexibility at the DOM level (and without
+ * the need for an intermediary conversion to user units, which avoids
+ * unnecessary overhead and rounding error).
+ *
+ * Example usage: to find out how many centimeters there are per inch:
+ *
+ * GetAbsUnitsPerAbsUnit(SVGLength_Binding::SVG_LENGTHTYPE_CM,
+ * SVGLength_Binding::SVG_LENGTHTYPE_IN)
+ */
+inline static float GetAbsUnitsPerAbsUnit(uint8_t aUnits, uint8_t aPerUnit) {
+ MOZ_ASSERT(IsAbsoluteUnit(aUnits), "Not a CSS absolute unit");
+ MOZ_ASSERT(IsAbsoluteUnit(aPerUnit), "Not a CSS absolute unit");
+
+ float CSSAbsoluteUnitConversionFactors[5][5] = {
+ // columns: cm, mm, in, pt, pc
+ // cm per...:
+ {1.0f, 0.1f, 2.54f, 0.035277777777777778f, 0.42333333333333333f},
+ // mm per...:
+ {10.0f, 1.0f, 25.4f, 0.35277777777777778f, 4.2333333333333333f},
+ // in per...:
+ {0.39370078740157481f, 0.039370078740157481f, 1.0f, 0.013888888888888889f,
+ 0.16666666666666667f},
+ // pt per...:
+ {28.346456692913386f, 2.8346456692913386f, 72.0f, 1.0f, 12.0f},
+ // pc per...:
+ {2.3622047244094489f, 0.23622047244094489f, 6.0f, 0.083333333333333333f,
+ 1.0f}};
+
+ // First absolute unit is SVG_LENGTHTYPE_CM = 6
+ return CSSAbsoluteUnitConversionFactors[aUnits - 6][aPerUnit - 6];
+}
+
+float SVGLength::GetValueInSpecifiedUnit(uint8_t aUnit,
+ const SVGElement* aElement,
+ uint8_t aAxis) const {
+ if (aUnit == mUnit) {
+ return mValue;
+ }
+ if ((aUnit == SVGLength_Binding::SVG_LENGTHTYPE_NUMBER &&
+ mUnit == SVGLength_Binding::SVG_LENGTHTYPE_PX) ||
+ (aUnit == SVGLength_Binding::SVG_LENGTHTYPE_PX &&
+ mUnit == SVGLength_Binding::SVG_LENGTHTYPE_NUMBER)) {
+ return mValue;
+ }
+ if (IsAbsoluteUnit(aUnit) && IsAbsoluteUnit(mUnit)) {
+ return mValue * GetAbsUnitsPerAbsUnit(aUnit, mUnit);
+ }
+
+ // Otherwise we do a two step conversion via user units. This can only
+ // succeed if aElement is non-null (although that's not sufficient to
+ // guarantee success).
+
+ float userUnitsPerCurrentUnit = GetUserUnitsPerUnit(aElement, aAxis);
+ float userUnitsPerNewUnit =
+ SVGLength(0.0f, aUnit).GetUserUnitsPerUnit(aElement, aAxis);
+
+ NS_ASSERTION(
+ userUnitsPerCurrentUnit >= 0 || !std::isfinite(userUnitsPerCurrentUnit),
+ "bad userUnitsPerCurrentUnit");
+ NS_ASSERTION(userUnitsPerNewUnit >= 0 || !std::isfinite(userUnitsPerNewUnit),
+ "bad userUnitsPerNewUnit");
+
+ float value = mValue * userUnitsPerCurrentUnit / userUnitsPerNewUnit;
+
+ // userUnitsPerCurrentUnit could be infinity, or userUnitsPerNewUnit could
+ // be zero.
+ if (std::isfinite(value)) {
+ return value;
+ }
+ return std::numeric_limits<float>::quiet_NaN();
+}
+
+#define INCHES_PER_MM_FLOAT float(0.0393700787)
+#define INCHES_PER_CM_FLOAT float(0.393700787)
+
+float SVGLength::GetUserUnitsPerUnit(const SVGElement* aElement,
+ uint8_t aAxis) const {
+ switch (mUnit) {
+ case SVGLength_Binding::SVG_LENGTHTYPE_NUMBER:
+ case SVGLength_Binding::SVG_LENGTHTYPE_PX:
+ return 1.0f;
+ case SVGLength_Binding::SVG_LENGTHTYPE_MM:
+ return INCHES_PER_MM_FLOAT * GetUserUnitsPerInch();
+ case SVGLength_Binding::SVG_LENGTHTYPE_CM:
+ return INCHES_PER_CM_FLOAT * GetUserUnitsPerInch();
+ case SVGLength_Binding::SVG_LENGTHTYPE_IN:
+ return GetUserUnitsPerInch();
+ case SVGLength_Binding::SVG_LENGTHTYPE_PT:
+ return (1.0f / POINTS_PER_INCH_FLOAT) * GetUserUnitsPerInch();
+ case SVGLength_Binding::SVG_LENGTHTYPE_PC:
+ return (12.0f / POINTS_PER_INCH_FLOAT) * GetUserUnitsPerInch();
+ case SVGLength_Binding::SVG_LENGTHTYPE_PERCENTAGE:
+ return GetUserUnitsPerPercent(aElement, aAxis);
+ case SVGLength_Binding::SVG_LENGTHTYPE_EMS:
+ return SVGContentUtils::GetFontSize(const_cast<SVGElement*>(aElement));
+ case SVGLength_Binding::SVG_LENGTHTYPE_EXS:
+ return SVGContentUtils::GetFontXHeight(const_cast<SVGElement*>(aElement));
+ default:
+ MOZ_ASSERT_UNREACHABLE("Unknown unit type");
+ return std::numeric_limits<float>::quiet_NaN();
+ }
+}
+
+/* static */
+float SVGLength::GetUserUnitsPerPercent(const SVGElement* aElement,
+ uint8_t aAxis) {
+ if (aElement) {
+ dom::SVGViewportElement* viewportElement = aElement->GetCtx();
+ if (viewportElement) {
+ return std::max(viewportElement->GetLength(aAxis) / 100.0f, 0.0f);
+ }
+ }
+ return std::numeric_limits<float>::quiet_NaN();
+}
+
+// Helpers:
+
+/* static */
+void SVGLength::GetUnitString(nsAString& aUnit, uint16_t aUnitType) {
+ switch (aUnitType) {
+ case SVG_LENGTHTYPE_NUMBER:
+ aUnit.Truncate();
+ return;
+ case SVG_LENGTHTYPE_PERCENTAGE:
+ aUnit.AssignLiteral("%");
+ return;
+ case SVG_LENGTHTYPE_EMS:
+ aUnit.AssignLiteral("em");
+ return;
+ case SVG_LENGTHTYPE_EXS:
+ aUnit.AssignLiteral("ex");
+ return;
+ case SVG_LENGTHTYPE_PX:
+ aUnit.AssignLiteral("px");
+ return;
+ case SVG_LENGTHTYPE_CM:
+ aUnit.AssignLiteral("cm");
+ return;
+ case SVG_LENGTHTYPE_MM:
+ aUnit.AssignLiteral("mm");
+ return;
+ case SVG_LENGTHTYPE_IN:
+ aUnit.AssignLiteral("in");
+ return;
+ case SVG_LENGTHTYPE_PT:
+ aUnit.AssignLiteral("pt");
+ return;
+ case SVG_LENGTHTYPE_PC:
+ aUnit.AssignLiteral("pc");
+ return;
+ }
+ MOZ_ASSERT_UNREACHABLE(
+ "Unknown unit type! Someone's using an SVGLength "
+ "with an invalid unit?");
+}
+
+/* static */
+uint16_t SVGLength::GetUnitTypeForString(const nsAString& aUnit) {
+ if (aUnit.IsEmpty()) {
+ return SVG_LENGTHTYPE_NUMBER;
+ }
+ if (aUnit.EqualsLiteral("%")) {
+ return SVG_LENGTHTYPE_PERCENTAGE;
+ }
+ if (aUnit.LowerCaseEqualsLiteral("em")) {
+ return SVG_LENGTHTYPE_EMS;
+ }
+ if (aUnit.LowerCaseEqualsLiteral("ex")) {
+ return SVG_LENGTHTYPE_EXS;
+ }
+ if (aUnit.LowerCaseEqualsLiteral("px")) {
+ return SVG_LENGTHTYPE_PX;
+ }
+ if (aUnit.LowerCaseEqualsLiteral("cm")) {
+ return SVG_LENGTHTYPE_CM;
+ }
+ if (aUnit.LowerCaseEqualsLiteral("mm")) {
+ return SVG_LENGTHTYPE_MM;
+ }
+ if (aUnit.LowerCaseEqualsLiteral("in")) {
+ return SVG_LENGTHTYPE_IN;
+ }
+ if (aUnit.LowerCaseEqualsLiteral("pt")) {
+ return SVG_LENGTHTYPE_PT;
+ }
+ if (aUnit.LowerCaseEqualsLiteral("pc")) {
+ return SVG_LENGTHTYPE_PC;
+ }
+ return SVG_LENGTHTYPE_UNKNOWN;
+}
+
+} // namespace mozilla