void RenderMathMLRow::layout()
{
RenderBlock::layout();
LayoutUnit maxHeight = 0;
int childCount = 0;
int operatorCount = 0;
// Calculate the non-operator max height of the row.
LayoutUnit operatorHeight = 0;
for (RenderObject* current = firstChild(); current; current = current->nextSibling()) {
childCount++;
if (current->isRenderMathMLBlock()) {
RenderMathMLBlock* block = toRenderMathMLBlock(current);
// Check to see if the non-operator block has a greater height.
if (!block->hasBase() && !block->isRenderMathMLOperator() && block->offsetHeight() > maxHeight)
maxHeight = block->offsetHeight();
if (block->hasBase() && block->nonOperatorHeight() > maxHeight)
maxHeight = block->nonOperatorHeight();
// If the block is an operator, capture the maximum height and increment the count.
if (block->isRenderMathMLOperator()) {
if (block->offsetHeight() > operatorHeight)
operatorHeight = block->offsetHeight();
operatorCount++;
}
} else if (current->isBoxModelObject()) {
RenderBoxModelObject* box = toRenderBoxModelObject(current);
// Check to see if this box has a larger height.
if (box->offsetHeight() > maxHeight)
maxHeight = box->offsetHeight();
}
}
if (childCount > 0 && childCount == operatorCount) {
// We have only operators and so set the max height to the operator height.
maxHeight = operatorHeight;
}
// Stretch everything to the same height (blocks can ignore the request).
if (maxHeight > 0) {
bool didStretch = false;
for (RenderObject* current = firstChild(); current; current = current->nextSibling()) {
if (current->isRenderMathMLBlock()) {
RenderMathMLBlock* block = toRenderMathMLBlock(current);
block->stretchToHeight(maxHeight);
didStretch = true;
}
}
if (didStretch) {
setNeedsLayout(true);
setPreferredLogicalWidthsDirty(true, false);
RenderBlock::layout();
}
}
}
void RenderMathMLRow::layout()
{
RenderBlock::layout();
// Calculate the maximum height of the row without the operators.
int maxHeight = nonOperatorHeight();
// Set the maximum height of the row for intermediate layouts.
style()->setHeight(Length(maxHeight, Fixed));
// Notify contained operators they may need to re-layout their stretched operators.
// We need to keep track of the number of children and operators because a row of
// operators needs some special handling.
int childCount = 0;
int operatorCount = 0;
for (RenderObject* current = firstChild(); current; current = current->nextSibling()) {
childCount++;
if (current->isRenderMathMLBlock()) {
RenderMathMLBlock* block = toRenderMathMLBlock(current);
block->stretchToHeight(maxHeight);
if (block->isRenderMathMLOperator())
operatorCount++;
}
}
// Layout the non-operators which have just been stretched.
setNeedsLayoutAndPrefWidthsRecalc();
markContainingBlocksForLayout();
RenderBlock::layout();
// Make a second pass with the real height of the operators.
int operatorHeight = 0;
for (RenderObject* current = firstChild(); current; current = current->nextSibling()) {
if (current->isRenderMathMLBlock()) {
RenderMathMLBlock* block = toRenderMathMLBlock(current);
if (!block->hasBase() && !block->isRenderMathMLOperator()) {
// Check to see if this box has a larger height.
if (block->offsetHeight() > maxHeight)
maxHeight = block->offsetHeight();
}
if (block->isRenderMathMLOperator())
if (block->offsetHeight() > operatorHeight)
operatorHeight = block->offsetHeight();
} else if (current->isBoxModelObject()) {
RenderBoxModelObject* box = toRenderBoxModelObject(current);
// Check to see if this box has a larger height.
if (box->offsetHeight() > maxHeight)
maxHeight = box->offsetHeight();
}
}
if (childCount > 0 && childCount == operatorCount) {
// We have only operators and so set the max height to the operator height.
maxHeight = operatorHeight;
}
int stretchHeight = maxHeight;
// Stretch the operators again and re-calculate the row height.
for (RenderObject* current = firstChild(); current; current = current->nextSibling()) {
if (current->isRenderMathMLBlock()) {
RenderMathMLBlock* block = toRenderMathMLBlock(current);
if (block->isRenderMathMLOperator()) {
RenderMathMLOperator* mathop = toRenderMathMLOperator(block);
mathop->stretchToHeight(stretchHeight);
} else {
block->stretchToHeight(stretchHeight);
RenderBoxModelObject* box = toRenderBoxModelObject(current);
// Check to see if this box has a larger height
if (box->offsetHeight() > maxHeight)
maxHeight = box->offsetHeight();
}
} else if (current->isBoxModelObject()) {
RenderBoxModelObject* box = toRenderBoxModelObject(current);
// Check to see if this box has a larger height
if (box->offsetHeight() > maxHeight)
maxHeight = box->offsetHeight();
}
}
// Set the maximum height of the row based on the calculations.
style()->setHeight(Length(maxHeight, Fixed));
// Do the final layout by calling our parent's layout again.
setNeedsLayoutAndPrefWidthsRecalc();
markContainingBlocksForLayout();
RenderBlock::layout();
}