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1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
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2 /* This Source Code Form is subject to the terms of the Mozilla Public |
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3 * License, v. 2.0. If a copy of the MPL was not distributed with this |
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4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
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5 |
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6 #include "nsMathMLmunderoverFrame.h" |
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7 #include "nsPresContext.h" |
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8 #include "nsRenderingContext.h" |
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9 #include "nsMathMLmmultiscriptsFrame.h" |
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10 #include <algorithm> |
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11 |
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12 // |
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13 // <munderover> -- attach an underscript-overscript pair to a base - implementation |
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14 // <mover> -- attach an overscript to a base - implementation |
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15 // <munder> -- attach an underscript to a base - implementation |
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16 // |
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17 |
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18 nsIFrame* |
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19 NS_NewMathMLmunderoverFrame(nsIPresShell* aPresShell, nsStyleContext* aContext) |
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20 { |
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21 return new (aPresShell) nsMathMLmunderoverFrame(aContext); |
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22 } |
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23 |
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24 NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmunderoverFrame) |
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25 |
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26 nsMathMLmunderoverFrame::~nsMathMLmunderoverFrame() |
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27 { |
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28 } |
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29 |
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30 nsresult |
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31 nsMathMLmunderoverFrame::AttributeChanged(int32_t aNameSpaceID, |
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32 nsIAtom* aAttribute, |
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33 int32_t aModType) |
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34 { |
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35 if (nsGkAtoms::accent_ == aAttribute || |
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36 nsGkAtoms::accentunder_ == aAttribute) { |
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37 // When we have automatic data to update within ourselves, we ask our |
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38 // parent to re-layout its children |
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39 return ReLayoutChildren(mParent); |
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40 } |
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41 |
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42 return nsMathMLContainerFrame:: |
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43 AttributeChanged(aNameSpaceID, aAttribute, aModType); |
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44 } |
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45 |
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46 NS_IMETHODIMP |
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47 nsMathMLmunderoverFrame::UpdatePresentationData(uint32_t aFlagsValues, |
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48 uint32_t aFlagsToUpdate) |
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49 { |
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50 nsMathMLContainerFrame::UpdatePresentationData(aFlagsValues, aFlagsToUpdate); |
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51 // disable the stretch-all flag if we are going to act like a subscript-superscript pair |
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52 if (NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishData.flags) && |
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53 StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE) { |
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54 mPresentationData.flags &= ~NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY; |
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55 } |
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56 else { |
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57 mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY; |
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58 } |
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59 return NS_OK; |
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60 } |
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61 |
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62 NS_IMETHODIMP |
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63 nsMathMLmunderoverFrame::InheritAutomaticData(nsIFrame* aParent) |
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64 { |
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65 // let the base class get the default from our parent |
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66 nsMathMLContainerFrame::InheritAutomaticData(aParent); |
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67 |
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68 mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY; |
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69 |
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70 return NS_OK; |
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71 } |
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72 |
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73 uint8_t |
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74 nsMathMLmunderoverFrame::ScriptIncrement(nsIFrame* aFrame) |
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75 { |
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76 nsIFrame* child = mFrames.FirstChild(); |
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77 if (!aFrame || aFrame == child) { |
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78 return 0; |
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79 } |
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80 child = child->GetNextSibling(); |
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81 if (aFrame == child) { |
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82 if (mContent->Tag() == nsGkAtoms::mover_) { |
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83 return mIncrementOver ? 1 : 0; |
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84 } |
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85 return mIncrementUnder ? 1 : 0; |
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86 } |
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87 if (child && aFrame == child->GetNextSibling()) { |
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88 // must be a over frame of munderover |
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89 return mIncrementOver ? 1 : 0; |
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90 } |
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91 return 0; // frame not found |
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92 } |
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93 |
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94 NS_IMETHODIMP |
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95 nsMathMLmunderoverFrame::TransmitAutomaticData() |
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96 { |
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97 // At this stage, all our children are in sync and we can fully |
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98 // resolve our own mEmbellishData struct |
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99 //--------------------------------------------------------------------- |
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100 |
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101 /* |
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102 The REC says: |
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103 |
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104 As regards munder (respectively mover) : |
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105 The default value of accentunder is false, unless underscript |
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106 is an <mo> element or an embellished operator. If underscript is |
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107 an <mo> element, the value of its accent attribute is used as the |
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108 default value of accentunder. If underscript is an embellished |
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109 operator, the accent attribute of the <mo> element at its |
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110 core is used as the default value. As with all attributes, an |
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111 explicitly given value overrides the default. |
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112 |
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113 XXX The winner is the outermost setting in conflicting settings like these: |
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114 <munder accentunder='true'> |
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115 <mi>...</mi> |
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116 <mo accentunder='false'> ... </mo> |
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117 </munder> |
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118 |
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119 As regards munderover: |
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120 The accent and accentunder attributes have the same effect as |
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121 the attributes with the same names on <mover> and <munder>, |
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122 respectively. Their default values are also computed in the |
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123 same manner as described for those elements, with the default |
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124 value of accent depending on overscript and the default value |
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125 of accentunder depending on underscript. |
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126 */ |
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127 |
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128 nsIFrame* overscriptFrame = nullptr; |
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129 nsIFrame* underscriptFrame = nullptr; |
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130 nsIFrame* baseFrame = mFrames.FirstChild(); |
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131 nsIAtom* tag = mContent->Tag(); |
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132 |
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133 if (baseFrame) { |
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134 if (tag == nsGkAtoms::munder_ || |
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135 tag == nsGkAtoms::munderover_) { |
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136 underscriptFrame = baseFrame->GetNextSibling(); |
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137 } else { |
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138 NS_ASSERTION(tag == nsGkAtoms::mover_, "mContent->Tag() not recognized"); |
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139 overscriptFrame = baseFrame->GetNextSibling(); |
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140 } |
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141 } |
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142 if (underscriptFrame && |
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143 tag == nsGkAtoms::munderover_) { |
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144 overscriptFrame = underscriptFrame->GetNextSibling(); |
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145 |
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146 } |
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147 |
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148 // if our base is an embellished operator, let its state bubble to us (in particular, |
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149 // this is where we get the flag for NS_MATHML_EMBELLISH_MOVABLELIMITS). Our flags |
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150 // are reset to the default values of false if the base frame isn't embellished. |
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151 mPresentationData.baseFrame = baseFrame; |
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152 GetEmbellishDataFrom(baseFrame, mEmbellishData); |
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153 |
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154 // The default value of accentunder is false, unless the underscript is embellished |
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155 // and its core <mo> is an accent |
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156 nsEmbellishData embellishData; |
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157 nsAutoString value; |
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158 if (tag == nsGkAtoms::munder_ || |
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159 tag == nsGkAtoms::munderover_) { |
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160 GetEmbellishDataFrom(underscriptFrame, embellishData); |
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161 if (NS_MATHML_EMBELLISH_IS_ACCENT(embellishData.flags)) { |
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162 mEmbellishData.flags |= NS_MATHML_EMBELLISH_ACCENTUNDER; |
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163 } else { |
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164 mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_ACCENTUNDER; |
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165 } |
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166 |
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167 // if we have an accentunder attribute, it overrides what the underscript said |
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168 if (mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::accentunder_, value)) { |
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169 if (value.EqualsLiteral("true")) { |
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170 mEmbellishData.flags |= NS_MATHML_EMBELLISH_ACCENTUNDER; |
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171 } else if (value.EqualsLiteral("false")) { |
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172 mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_ACCENTUNDER; |
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173 } |
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174 } |
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175 } |
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176 |
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177 // The default value of accent is false, unless the overscript is embellished |
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178 // and its core <mo> is an accent |
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179 if (tag == nsGkAtoms::mover_ || |
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180 tag == nsGkAtoms::munderover_) { |
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181 GetEmbellishDataFrom(overscriptFrame, embellishData); |
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182 if (NS_MATHML_EMBELLISH_IS_ACCENT(embellishData.flags)) { |
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183 mEmbellishData.flags |= NS_MATHML_EMBELLISH_ACCENTOVER; |
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184 } else { |
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185 mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_ACCENTOVER; |
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186 } |
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187 |
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188 // if we have an accent attribute, it overrides what the overscript said |
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189 if (mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::accent_, value)) { |
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190 if (value.EqualsLiteral("true")) { |
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191 mEmbellishData.flags |= NS_MATHML_EMBELLISH_ACCENTOVER; |
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192 } else if (value.EqualsLiteral("false")) { |
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193 mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_ACCENTOVER; |
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194 } |
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195 } |
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196 } |
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197 |
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198 bool subsupDisplay = |
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199 NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishData.flags) && |
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200 StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE; |
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201 |
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202 // disable the stretch-all flag if we are going to act like a superscript |
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203 if (subsupDisplay) { |
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204 mPresentationData.flags &= ~NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY; |
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205 } |
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206 |
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207 // Now transmit any change that we want to our children so that they |
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208 // can update their mPresentationData structs |
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209 //--------------------------------------------------------------------- |
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210 |
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211 /* The REC says: |
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212 Within underscript, <munderover> always sets displaystyle to "false", |
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213 but increments scriptlevel by 1 only when accentunder is "false". |
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214 |
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215 Within overscript, <munderover> always sets displaystyle to "false", |
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216 but increments scriptlevel by 1 only when accent is "false". |
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217 |
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218 Within subscript and superscript it increments scriptlevel by 1, and |
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219 sets displaystyle to "false", but leaves both attributes unchanged within |
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220 base. |
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221 |
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222 The TeXBook treats 'over' like a superscript, so p.141 or Rule 13a |
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223 say it shouldn't be compressed. However, The TeXBook says |
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224 that math accents and \overline change uncramped styles to their |
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225 cramped counterparts. |
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226 */ |
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227 if (tag == nsGkAtoms::mover_ || |
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228 tag == nsGkAtoms::munderover_) { |
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229 uint32_t compress = NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags) |
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230 ? NS_MATHML_COMPRESSED : 0; |
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231 mIncrementOver = |
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232 !NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags) || |
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233 subsupDisplay; |
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234 SetIncrementScriptLevel(tag == nsGkAtoms::mover_ ? 1 : 2, mIncrementOver); |
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235 if (mIncrementOver) { |
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236 PropagateFrameFlagFor(overscriptFrame, |
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237 NS_FRAME_MATHML_SCRIPT_DESCENDANT); |
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238 } |
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239 PropagatePresentationDataFor(overscriptFrame, compress, compress); |
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240 } |
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241 /* |
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242 The TeXBook treats 'under' like a subscript, so p.141 or Rule 13a |
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243 say it should be compressed |
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244 */ |
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245 if (tag == nsGkAtoms::munder_ || |
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246 tag == nsGkAtoms::munderover_) { |
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247 mIncrementUnder = |
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248 !NS_MATHML_EMBELLISH_IS_ACCENTUNDER(mEmbellishData.flags) || |
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249 subsupDisplay; |
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250 SetIncrementScriptLevel(1, mIncrementUnder); |
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251 if (mIncrementUnder) { |
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252 PropagateFrameFlagFor(underscriptFrame, |
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253 NS_FRAME_MATHML_SCRIPT_DESCENDANT); |
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254 } |
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255 PropagatePresentationDataFor(underscriptFrame, |
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256 NS_MATHML_COMPRESSED, |
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257 NS_MATHML_COMPRESSED); |
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258 } |
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259 return NS_OK; |
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260 } |
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261 |
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262 /* |
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263 The REC says: |
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264 * If the base is an operator with movablelimits="true" (or an embellished |
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265 operator whose <mo> element core has movablelimits="true"), and |
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266 displaystyle="false", then underscript and overscript are drawn in |
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267 a subscript and superscript position, respectively. In this case, |
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268 the accent and accentunder attributes are ignored. This is often |
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269 used for limits on symbols such as ∑. |
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270 |
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271 i.e.,: |
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272 if (NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishDataflags) && |
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273 StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE) { |
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274 // place like subscript-superscript pair |
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275 } |
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276 else { |
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277 // place like underscript-overscript pair |
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278 } |
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279 */ |
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280 |
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281 /* virtual */ nsresult |
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282 nsMathMLmunderoverFrame::Place(nsRenderingContext& aRenderingContext, |
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283 bool aPlaceOrigin, |
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284 nsHTMLReflowMetrics& aDesiredSize) |
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285 { |
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286 nsIAtom* tag = mContent->Tag(); |
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287 if (NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishData.flags) && |
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288 StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE) { |
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289 //place like sub sup or subsup |
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290 nscoord scriptSpace = nsPresContext::CSSPointsToAppUnits(0.5f); |
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291 if (tag == nsGkAtoms::munderover_) { |
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292 return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(), |
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293 aRenderingContext, |
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294 aPlaceOrigin, |
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295 aDesiredSize, |
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296 this, 0, 0, |
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297 scriptSpace); |
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298 } else if (tag == nsGkAtoms::munder_) { |
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299 return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(), |
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300 aRenderingContext, |
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301 aPlaceOrigin, |
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302 aDesiredSize, |
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303 this, 0, 0, |
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304 scriptSpace); |
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305 } else { |
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306 NS_ASSERTION(tag == nsGkAtoms::mover_, "mContent->Tag() not recognized"); |
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307 return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(), |
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308 aRenderingContext, |
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309 aPlaceOrigin, |
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310 aDesiredSize, |
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311 this, 0, 0, |
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312 scriptSpace); |
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313 } |
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314 |
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315 } |
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316 |
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317 //////////////////////////////////// |
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318 // Get the children's desired sizes |
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319 |
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320 nsBoundingMetrics bmBase, bmUnder, bmOver; |
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321 nsHTMLReflowMetrics baseSize(aDesiredSize.GetWritingMode()); |
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322 nsHTMLReflowMetrics underSize(aDesiredSize.GetWritingMode()); |
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323 nsHTMLReflowMetrics overSize(aDesiredSize.GetWritingMode()); |
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324 nsIFrame* overFrame = nullptr; |
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325 nsIFrame* underFrame = nullptr; |
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326 nsIFrame* baseFrame = mFrames.FirstChild(); |
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327 underSize.SetTopAscent(0); |
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328 overSize.SetTopAscent(0); |
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329 bool haveError = false; |
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330 if (baseFrame) { |
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331 if (tag == nsGkAtoms::munder_ || |
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332 tag == nsGkAtoms::munderover_) { |
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333 underFrame = baseFrame->GetNextSibling(); |
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334 } else if (tag == nsGkAtoms::mover_) { |
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335 overFrame = baseFrame->GetNextSibling(); |
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336 } |
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337 } |
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338 if (underFrame && tag == nsGkAtoms::munderover_) { |
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339 overFrame = underFrame->GetNextSibling(); |
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340 } |
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341 |
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342 if (tag == nsGkAtoms::munder_) { |
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343 if (!baseFrame || !underFrame || underFrame->GetNextSibling()) { |
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344 // report an error, encourage people to get their markups in order |
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345 haveError = true; |
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346 } |
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347 } |
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348 if (tag == nsGkAtoms::mover_) { |
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349 if (!baseFrame || !overFrame || overFrame->GetNextSibling()) { |
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350 // report an error, encourage people to get their markups in order |
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351 haveError = true; |
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352 } |
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353 } |
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354 if (tag == nsGkAtoms::munderover_) { |
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355 if (!baseFrame || !underFrame || !overFrame || overFrame->GetNextSibling()) { |
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356 // report an error, encourage people to get their markups in order |
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357 haveError = true; |
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358 } |
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359 } |
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360 if (haveError) { |
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361 if (aPlaceOrigin) { |
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362 ReportChildCountError(); |
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363 } |
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364 return ReflowError(aRenderingContext, aDesiredSize); |
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365 } |
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366 GetReflowAndBoundingMetricsFor(baseFrame, baseSize, bmBase); |
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367 if (underFrame) { |
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368 GetReflowAndBoundingMetricsFor(underFrame, underSize, bmUnder); |
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369 } |
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370 if (overFrame) { |
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371 GetReflowAndBoundingMetricsFor(overFrame, overSize, bmOver); |
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372 } |
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373 |
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374 nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1); |
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375 |
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376 //////////////////// |
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377 // Place Children |
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378 |
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379 nsRefPtr<nsFontMetrics> fm; |
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380 nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fm)); |
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381 aRenderingContext.SetFont(fm); |
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382 |
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383 nscoord xHeight = fm->XHeight(); |
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384 |
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385 nscoord ruleThickness; |
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386 GetRuleThickness (aRenderingContext, fm, ruleThickness); |
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387 |
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388 nscoord correction = 0; |
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389 GetItalicCorrection (bmBase, correction); |
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390 |
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391 // there are 2 different types of placement depending on |
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392 // whether we want an accented under or not |
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393 |
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394 nscoord underDelta1 = 0; // gap between base and underscript |
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395 nscoord underDelta2 = 0; // extra space beneath underscript |
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396 |
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397 if (!NS_MATHML_EMBELLISH_IS_ACCENTUNDER(mEmbellishData.flags)) { |
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398 // Rule 13a, App. G, TeXbook |
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399 nscoord bigOpSpacing2, bigOpSpacing4, bigOpSpacing5, dummy; |
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400 GetBigOpSpacings (fm, |
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401 dummy, bigOpSpacing2, |
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402 dummy, bigOpSpacing4, |
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403 bigOpSpacing5); |
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404 underDelta1 = std::max(bigOpSpacing2, (bigOpSpacing4 - bmUnder.ascent)); |
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405 underDelta2 = bigOpSpacing5; |
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406 } |
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407 else { |
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408 // No corresponding rule in TeXbook - we are on our own here |
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409 // XXX tune the gap delta between base and underscript |
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410 |
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411 // Should we use Rule 10 like \underline does? |
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412 underDelta1 = ruleThickness + onePixel/2; |
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413 underDelta2 = ruleThickness; |
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414 } |
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415 // empty under? |
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416 if (!(bmUnder.ascent + bmUnder.descent)) { |
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417 underDelta1 = 0; |
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418 underDelta2 = 0; |
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419 } |
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420 |
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421 nscoord overDelta1 = 0; // gap between base and overscript |
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422 nscoord overDelta2 = 0; // extra space above overscript |
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423 |
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424 if (!NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags)) { |
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425 // Rule 13a, App. G, TeXbook |
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426 nscoord bigOpSpacing1, bigOpSpacing3, bigOpSpacing5, dummy; |
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427 GetBigOpSpacings (fm, |
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428 bigOpSpacing1, dummy, |
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429 bigOpSpacing3, dummy, |
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430 bigOpSpacing5); |
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431 overDelta1 = std::max(bigOpSpacing1, (bigOpSpacing3 - bmOver.descent)); |
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432 overDelta2 = bigOpSpacing5; |
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433 |
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434 // XXX This is not a TeX rule... |
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435 // delta1 (as computed abvove) can become really big when bmOver.descent is |
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436 // negative, e.g., if the content is &OverBar. In such case, we use the height |
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437 if (bmOver.descent < 0) |
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438 overDelta1 = std::max(bigOpSpacing1, (bigOpSpacing3 - (bmOver.ascent + bmOver.descent))); |
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439 } |
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440 else { |
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441 // Rule 12, App. G, TeXbook |
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442 // We are going to modify this rule to make it more general. |
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443 // The idea behind Rule 12 in the TeXBook is to keep the accent |
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444 // as close to the base as possible, while ensuring that the |
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445 // distance between the *baseline* of the accent char and |
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446 // the *baseline* of the base is atleast x-height. |
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447 // The idea is that for normal use, we would like all the accents |
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448 // on a line to line up atleast x-height above the baseline |
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449 // if possible. |
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450 // When the ascent of the base is >= x-height, |
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451 // the baseline of the accent char is placed just above the base |
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452 // (specifically, the baseline of the accent char is placed |
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453 // above the baseline of the base by the ascent of the base). |
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454 // For ease of implementation, |
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455 // this assumes that the font-designer designs accents |
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456 // in such a way that the bottom of the accent is atleast x-height |
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457 // above its baseline, otherwise there will be collisions |
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458 // with the base. Also there should be proper padding between |
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459 // the bottom of the accent char and its baseline. |
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460 // The above rule may not be obvious from a first |
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461 // reading of rule 12 in the TeXBook !!! |
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462 // The mathml <mover> tag can use accent chars that |
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463 // do not follow this convention. So we modify TeX's rule |
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464 // so that TeX's rule gets subsumed for accents that follow |
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465 // TeX's convention, |
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466 // while also allowing accents that do not follow the convention : |
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467 // we try to keep the *bottom* of the accent char atleast x-height |
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468 // from the baseline of the base char. we also slap on an extra |
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469 // padding between the accent and base chars. |
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470 overDelta1 = ruleThickness + onePixel/2; |
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471 if (bmBase.ascent < xHeight) { |
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472 // also ensure at least x-height above the baseline of the base |
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473 overDelta1 += xHeight - bmBase.ascent; |
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474 } |
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475 overDelta2 = ruleThickness; |
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476 } |
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477 // empty over? |
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478 if (!(bmOver.ascent + bmOver.descent)) { |
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479 overDelta1 = 0; |
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480 overDelta2 = 0; |
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481 } |
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482 |
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483 nscoord dxBase = 0, dxOver = 0, dxUnder = 0; |
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484 nsAutoString valueAlign; |
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485 enum { |
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486 center, |
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487 left, |
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488 right |
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489 } alignPosition = center; |
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490 |
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491 if (mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::align, valueAlign)) { |
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492 if (valueAlign.EqualsLiteral("left")) { |
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493 alignPosition = left; |
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494 } else if (valueAlign.EqualsLiteral("right")) { |
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495 alignPosition = right; |
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496 } |
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497 } |
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498 |
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499 ////////// |
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500 // pass 1, do what <mover> does: attach the overscript on the base |
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501 |
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502 // Ad-hoc - This is to override fonts which have ready-made _accent_ |
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503 // glyphs with negative lbearing and rbearing. We want to position |
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504 // the overscript ourselves |
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505 nscoord overWidth = bmOver.width; |
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506 if (!overWidth && (bmOver.rightBearing - bmOver.leftBearing > 0)) { |
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507 overWidth = bmOver.rightBearing - bmOver.leftBearing; |
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508 dxOver = -bmOver.leftBearing; |
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509 } |
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510 |
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511 if (NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags)) { |
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512 mBoundingMetrics.width = bmBase.width; |
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513 if (alignPosition == center) { |
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514 dxOver += correction; |
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515 } |
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516 } |
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517 else { |
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518 mBoundingMetrics.width = std::max(bmBase.width, overWidth); |
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519 if (alignPosition == center) { |
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520 dxOver += correction/2; |
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521 } |
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522 } |
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523 |
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524 if (alignPosition == center) { |
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525 dxOver += (mBoundingMetrics.width - overWidth)/2; |
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526 dxBase = (mBoundingMetrics.width - bmBase.width)/2; |
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527 } else if (alignPosition == right) { |
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528 dxOver += mBoundingMetrics.width - overWidth; |
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529 dxBase = mBoundingMetrics.width - bmBase.width; |
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530 } |
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531 |
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532 mBoundingMetrics.ascent = |
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533 bmBase.ascent + overDelta1 + bmOver.ascent + bmOver.descent; |
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534 mBoundingMetrics.descent = bmBase.descent; |
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535 mBoundingMetrics.leftBearing = |
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536 std::min(dxBase + bmBase.leftBearing, dxOver + bmOver.leftBearing); |
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537 mBoundingMetrics.rightBearing = |
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538 std::max(dxBase + bmBase.rightBearing, dxOver + bmOver.rightBearing); |
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539 |
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540 ////////// |
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541 // pass 2, do what <munder> does: attach the underscript on the previous |
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542 // result. We conceptually view the previous result as an "anynomous base" |
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543 // from where to attach the underscript. Hence if the underscript is empty, |
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544 // we should end up like <mover>. If the overscript is empty, we should |
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545 // end up like <munder>. |
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546 |
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547 nsBoundingMetrics bmAnonymousBase = mBoundingMetrics; |
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548 nscoord ascentAnonymousBase = |
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549 std::max(mBoundingMetrics.ascent + overDelta2, |
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550 overSize.TopAscent() + bmOver.descent + overDelta1 + bmBase.ascent); |
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551 ascentAnonymousBase = std::max(ascentAnonymousBase, baseSize.TopAscent()); |
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552 |
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553 // Width of non-spacing marks is zero so use left and right bearing. |
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554 nscoord underWidth = bmUnder.width; |
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555 if (!underWidth) { |
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556 underWidth = bmUnder.rightBearing - bmUnder.leftBearing; |
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557 dxUnder = -bmUnder.leftBearing; |
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558 } |
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559 |
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560 nscoord maxWidth = std::max(bmAnonymousBase.width, underWidth); |
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561 if (alignPosition == center && |
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562 !NS_MATHML_EMBELLISH_IS_ACCENTUNDER(mEmbellishData.flags)) { |
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563 GetItalicCorrection(bmAnonymousBase, correction); |
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564 dxUnder += -correction/2; |
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565 } |
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566 nscoord dxAnonymousBase = 0; |
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567 if (alignPosition == center) { |
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568 dxUnder += (maxWidth - underWidth)/2; |
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569 dxAnonymousBase = (maxWidth - bmAnonymousBase.width)/2; |
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570 } else if (alignPosition == right) { |
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571 dxUnder += maxWidth - underWidth; |
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572 dxAnonymousBase = maxWidth - bmAnonymousBase.width; |
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573 } |
|
574 |
|
575 // adjust the offsets of the real base and overscript since their |
|
576 // final offsets should be relative to us... |
|
577 dxOver += dxAnonymousBase; |
|
578 dxBase += dxAnonymousBase; |
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579 |
|
580 mBoundingMetrics.width = |
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581 std::max(dxAnonymousBase + bmAnonymousBase.width, dxUnder + bmUnder.width); |
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582 // At this point, mBoundingMetrics.ascent = bmAnonymousBase.ascent |
|
583 mBoundingMetrics.descent = |
|
584 bmAnonymousBase.descent + underDelta1 + bmUnder.ascent + bmUnder.descent; |
|
585 mBoundingMetrics.leftBearing = |
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586 std::min(dxAnonymousBase + bmAnonymousBase.leftBearing, dxUnder + bmUnder.leftBearing); |
|
587 mBoundingMetrics.rightBearing = |
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588 std::max(dxAnonymousBase + bmAnonymousBase.rightBearing, dxUnder + bmUnder.rightBearing); |
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589 |
|
590 aDesiredSize.SetTopAscent(ascentAnonymousBase); |
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591 aDesiredSize.Height() = aDesiredSize.TopAscent() + |
|
592 std::max(mBoundingMetrics.descent + underDelta2, |
|
593 bmAnonymousBase.descent + underDelta1 + bmUnder.ascent + |
|
594 underSize.Height() - underSize.TopAscent()); |
|
595 aDesiredSize.Height() = std::max(aDesiredSize.Height(), |
|
596 aDesiredSize.TopAscent() + |
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597 baseSize.Height() - baseSize.TopAscent()); |
|
598 aDesiredSize.Width() = mBoundingMetrics.width; |
|
599 aDesiredSize.mBoundingMetrics = mBoundingMetrics; |
|
600 |
|
601 mReference.x = 0; |
|
602 mReference.y = aDesiredSize.TopAscent(); |
|
603 |
|
604 if (aPlaceOrigin) { |
|
605 nscoord dy; |
|
606 // place overscript |
|
607 if (overFrame) { |
|
608 dy = aDesiredSize.TopAscent() - mBoundingMetrics.ascent + bmOver.ascent |
|
609 - overSize.TopAscent(); |
|
610 FinishReflowChild (overFrame, PresContext(), overSize, nullptr, dxOver, dy, 0); |
|
611 } |
|
612 // place base |
|
613 dy = aDesiredSize.TopAscent() - baseSize.TopAscent(); |
|
614 FinishReflowChild (baseFrame, PresContext(), baseSize, nullptr, dxBase, dy, 0); |
|
615 // place underscript |
|
616 if (underFrame) { |
|
617 dy = aDesiredSize.TopAscent() + mBoundingMetrics.descent - bmUnder.descent |
|
618 - underSize.TopAscent(); |
|
619 FinishReflowChild (underFrame, PresContext(), underSize, nullptr, |
|
620 dxUnder, dy, 0); |
|
621 } |
|
622 } |
|
623 return NS_OK; |
|
624 } |