/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
// vim:cindent:ts=4:et:sw=4:
/* 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/. */
/*
* Web-compatible algorithms that determine column and table widths,
* used for CSS2's 'table-layout: auto'.
*/
#include "BasicTableLayoutStrategy.h"
#include <algorithm>
#include "nsTableFrame.h"
#include "nsTableColFrame.h"
#include "nsTableCellFrame.h"
#include "nsLayoutUtils.h"
#include "nsGkAtoms.h"
#include "SpanningCellSorter.h"
#include "nsIContent.h"
using namespace mozilla;
using namespace mozilla::layout;
namespace css = mozilla::css;
#undef DEBUG_TABLE_STRATEGY
BasicTableLayoutStrategy::BasicTableLayoutStrategy(nsTableFrame *aTableFrame)
: nsITableLayoutStrategy(nsITableLayoutStrategy::Auto),
mTableFrame(aTableFrame) {
MarkIntrinsicISizesDirty();
}
/* virtual */
BasicTableLayoutStrategy::~BasicTableLayoutStrategy() {}
/* virtual */ nscoord BasicTableLayoutStrategy::GetMinISize(
gfxContext *aRenderingContext) {
DISPLAY_MIN_WIDTH(mTableFrame, mMinISize);
if (mMinISize == NS_INTRINSIC_WIDTH_UNKNOWN) {
ComputeIntrinsicISizes(aRenderingContext);
}
return mMinISize;
}
/* virtual */ nscoord BasicTableLayoutStrategy::GetPrefISize(
gfxContext *aRenderingContext, bool aComputingSize) {
DISPLAY_PREF_WIDTH(mTableFrame, mPrefISize);
NS_ASSERTION((mPrefISize == NS_INTRINSIC_WIDTH_UNKNOWN) ==
(mPrefISizePctExpand == NS_INTRINSIC_WIDTH_UNKNOWN),
"dirtyness out of sync");
if (mPrefISize == NS_INTRINSIC_WIDTH_UNKNOWN) {
ComputeIntrinsicISizes(aRenderingContext);
}
return aComputingSize ? mPrefISizePctExpand : mPrefISize;
}
struct CellISizeInfo {
CellISizeInfo(nscoord aMinCoord, nscoord aPrefCoord, float aPrefPercent,
bool aHasSpecifiedISize)
: hasSpecifiedISize(aHasSpecifiedISize),
minCoord(aMinCoord),
prefCoord(aPrefCoord),
prefPercent(aPrefPercent) {}
bool hasSpecifiedISize;
nscoord minCoord;
nscoord prefCoord;
float prefPercent;
};
// Used for both column and cell calculations. The parts needed only
// for cells are skipped when aIsCell is false.
static CellISizeInfo GetISizeInfo(gfxContext *aRenderingContext,
nsIFrame *aFrame, WritingMode aWM,
bool aIsCell) {
nscoord minCoord, prefCoord;
const nsStylePosition *stylePos = aFrame->StylePosition();
bool isQuirks =
aFrame->PresContext()->CompatibilityMode() == eCompatibility_NavQuirks;
nscoord boxSizingToBorderEdge = 0;
if (aIsCell) {
// If aFrame is a container for font size inflation, then shrink
// wrapping inside of it should not apply font size inflation.
AutoMaybeDisableFontInflation an(aFrame);
minCoord = aFrame->GetMinISize(aRenderingContext);
prefCoord = aFrame->GetPrefISize(aRenderingContext);
// Until almost the end of this function, minCoord and prefCoord
// represent the box-sizing based isize values (which mean they
// should include inline padding and border width when
// box-sizing is set to border-box).
// Note that this function returns border-box isize, we add the
// outer edges near the end of this function.
// XXX Should we ignore percentage padding?
nsIFrame::IntrinsicISizeOffsetData offsets =
aFrame->IntrinsicISizeOffsets();
// In quirks mode, table cell isize should be content-box,
// but bsize should be border box.
// Because of this historic anomaly, we do not use quirk.css.
// (We can't specify one value of box-sizing for isize and another
// for bsize).
// For this reason, we also do not use box-sizing for just one of
// them, as this may be confusing.
if (isQuirks || stylePos->mBoxSizing == StyleBoxSizing::Content) {
boxSizingToBorderEdge = offsets.hPadding + offsets.hBorder;
} else {
// StyleBoxSizing::Border and standards-mode
minCoord += offsets.hPadding + offsets.hBorder;
prefCoord += offsets.hPadding + offsets.hBorder;
}
} else {
minCoord = 0;
prefCoord = 0;
}
float prefPercent = 0.0f;
bool hasSpecifiedISize = false;
const nsStyleCoord &iSize = stylePos->ISize(aWM);
nsStyleUnit unit = iSize.GetUnit();
// NOTE: We're ignoring calc() units with percentages here, for lack of a
// sensible idea for what to do with them. This means calc() with
// percentages is basically handled like 'auto' for table cells and
// columns.
if (iSize.ConvertsToLength()) {
hasSpecifiedISize = true;
// Note: since ComputeISizeValue was designed to return content-box
// isize, it will (in some cases) subtract the box-sizing edges.
// We prevent this unwanted behavior by calling it with
// aContentEdgeToBoxSizing and aBoxSizingToMarginEdge set to 0.
nscoord c = aFrame->ComputeISizeValue(aRenderingContext, 0, 0, 0, iSize);
// Quirk: A cell with "nowrap" set and a coord value for the
// isize which is bigger than the intrinsic minimum isize uses
// that coord value as the minimum isize.
// This is kept up-to-date with dynamic changes to nowrap by code in
// nsTableCellFrame::AttributeChanged
if (aIsCell && c > minCoord && isQuirks &&
aFrame->GetContent()->AsElement()->HasAttr(kNameSpaceID_None,
nsGkAtoms::nowrap)) {
minCoord = c;
}
prefCoord = std::max(c, minCoord);
} else if (unit == eStyleUnit_Percent) {
prefPercent = iSize.GetPercentValue();
} else if (unit == eStyleUnit_Enumerated && aIsCell) {
switch (iSize.GetIntValue()) {
case NS_STYLE_WIDTH_MAX_CONTENT:
// 'inline-size' only affects pref isize, not min
// isize, so don't change anything
break;
case NS_STYLE_WIDTH_MIN_CONTENT:
prefCoord = minCoord;
break;
case NS_STYLE_WIDTH_FIT_CONTENT:
case NS_STYLE_WIDTH_AVAILABLE:
// act just like 'inline-size: auto'
break;
default:
NS_NOTREACHED("unexpected enumerated value");
}
}
nsStyleCoord maxISize(stylePos->MaxISize(aWM));
if (maxISize.GetUnit() == eStyleUnit_Enumerated) {
if (!aIsCell || maxISize.GetIntValue() == NS_STYLE_WIDTH_AVAILABLE) {
maxISize.SetNoneValue();
} else if (maxISize.GetIntValue() == NS_STYLE_WIDTH_FIT_CONTENT) {
// for 'max-inline-size', '-moz-fit-content' is like
// '-moz-max-content'
maxISize.SetIntValue(NS_STYLE_WIDTH_MAX_CONTENT, eStyleUnit_Enumerated);
}
}
unit = maxISize.GetUnit();
// XXX To really implement 'max-inline-size' well, we'd need to store
// it separately on the columns.
if (maxISize.ConvertsToLength() || unit == eStyleUnit_Enumerated) {
nscoord c = aFrame->ComputeISizeValue(aRenderingContext, 0, 0, 0, maxISize);
minCoord = std::min(c, minCoord);
prefCoord = std::min(c, prefCoord);
} else if (unit == eStyleUnit_Percent) {
float p = stylePos->MaxISize(aWM).GetPercentValue();
if (p < prefPercent) {
prefPercent = p;
}
}
// treat calc() with percentages on max-inline-size just like 'none'.
nsStyleCoord minISize(stylePos->MinISize(aWM));
if (minISize.GetUnit() == eStyleUnit_Enumerated) {
if (!aIsCell || minISize.GetIntValue() == NS_STYLE_WIDTH_AVAILABLE) {
minISize.SetCoordValue(0);
} else if (minISize.GetIntValue() == NS_STYLE_WIDTH_FIT_CONTENT) {
// for 'min-inline-size', '-moz-fit-content' is like
// '-moz-min-content'
minISize.SetIntValue(NS_STYLE_WIDTH_MIN_CONTENT, eStyleUnit_Enumerated);
}
}
unit = minISize.GetUnit();
if (minISize.ConvertsToLength() || unit == eStyleUnit_Enumerated) {
nscoord c = aFrame->ComputeISizeValue(aRenderingContext, 0, 0, 0, minISize);
minCoord = std::max(c, minCoord);
prefCoord = std::max(c, prefCoord);
} else if (unit == eStyleUnit_Percent) {
float p = stylePos->MinISize(aWM).GetPercentValue();
if (p > prefPercent) {
prefPercent = p;
}
}
// treat calc() with percentages on min-inline-size just like '0'.
// XXX Should col frame have border/padding considered?
if (aIsCell) {
minCoord += boxSizingToBorderEdge;
prefCoord = NSCoordSaturatingAdd(prefCoord, boxSizingToBorderEdge);
}
return CellISizeInfo(minCoord, prefCoord, prefPercent, hasSpecifiedISize);
}
static inline CellISizeInfo GetCellISizeInfo(gfxContext *aRenderingContext,
nsTableCellFrame *aCellFrame,
WritingMode aWM) {
return GetISizeInfo(aRenderingContext, aCellFrame, aWM, true);
}
static inline CellISizeInfo GetColISizeInfo(gfxContext *aRenderingContext,
nsIFrame *aFrame, WritingMode aWM) {
return GetISizeInfo(aRenderingContext, aFrame, aWM, false);
}
/**
* The algorithm in this function, in addition to meeting the
* requirements of Web-compatibility, is also invariant under reordering
* of the rows within a table (something that most, but not all, other
* browsers are).
*/
void BasicTableLayoutStrategy::ComputeColumnIntrinsicISizes(
gfxContext *aRenderingContext) {
nsTableFrame *tableFrame = mTableFrame;
nsTableCellMap *cellMap = tableFrame->GetCellMap();
WritingMode wm = tableFrame->GetWritingMode();
mozilla::AutoStackArena arena;
SpanningCellSorter spanningCells;
// Loop over the columns to consider the columns and cells *without*
// a colspan.
int32_t col, col_end;
for (col = 0, col_end = cellMap->GetColCount(); col < col_end; ++col) {
nsTableColFrame *colFrame = tableFrame->GetColFrame(col);
if (!colFrame) {
NS_ERROR("column frames out of sync with cell map");
continue;
}
colFrame->ResetIntrinsics();
colFrame->ResetSpanIntrinsics();
// Consider the isizes on the column.
CellISizeInfo colInfo = GetColISizeInfo(aRenderingContext, colFrame, wm);
colFrame->AddCoords(colInfo.minCoord, colInfo.prefCoord,
colInfo.hasSpecifiedISize);
colFrame->AddPrefPercent(colInfo.prefPercent);
// Consider the isizes on the column-group. Note that we follow
// what the HTML spec says here, and make the isize apply to
// each column in the group, not the group as a whole.
// If column has isize, column-group doesn't override isize.
if (colInfo.minCoord == 0 && colInfo.prefCoord == 0 &&
colInfo.prefPercent == 0.0f) {
NS_ASSERTION(colFrame->GetParent()->IsTableColGroupFrame(),
"expected a column-group");
colInfo = GetColISizeInfo(aRenderingContext, colFrame->GetParent(), wm);
colFrame->AddCoords(colInfo.minCoord, colInfo.prefCoord,
colInfo.hasSpecifiedISize);
colFrame->AddPrefPercent(colInfo.prefPercent);
}
// Consider the contents of and the isizes on the cells without
// colspans.
nsCellMapColumnIterator columnIter(cellMap, col);
int32_t row, colSpan;
nsTableCellFrame *cellFrame;
while ((cellFrame = columnIter.GetNextFrame(&row, &colSpan))) {
if (colSpan > 1) {
spanningCells.AddCell(colSpan, row, col);
continue;
}
CellISizeInfo info = GetCellISizeInfo(aRenderingContext, cellFrame, wm);
colFrame->AddCoords(info.minCoord, info.prefCoord,
info.hasSpecifiedISize);
colFrame->AddPrefPercent(info.prefPercent);
}
#ifdef DEBUG_dbaron_off
printf("table %p col %d nonspan: min=%d pref=%d spec=%d pct=%f\n",
mTableFrame, col, colFrame->GetMinCoord(), colFrame->GetPrefCoord(),
colFrame->GetHasSpecifiedCoord(), colFrame->GetPrefPercent());
#endif
}
#ifdef DEBUG_TABLE_STRATEGY
printf("ComputeColumnIntrinsicISizes single\n");
mTableFrame->Dump(false, true, false);
#endif
// Consider the cells with a colspan that we saved in the loop above
// into the spanning cell sorter. We consider these cells by seeing
// if they require adding to the isizes resulting only from cells
// with a smaller colspan, and therefore we must process them sorted
// in increasing order by colspan. For each colspan group, we
// accumulate new values to accumulate in the column frame's Span*
// members.
//
// Considering things only relative to the isizes resulting from
// cells with smaller colspans (rather than incrementally including
// the results from spanning cells, or doing spanning and
// non-spanning cells in a single pass) means that layout remains
// row-order-invariant and (except for percentage isizes that add to
// more than 100%) column-order invariant.
//
// Starting with smaller colspans makes it more likely that we
// satisfy all the constraints given and don't distribute space to
// columns where we don't need it.
SpanningCellSorter::Item *item;
int32_t colSpan;
while ((item = spanningCells.GetNext(&colSpan))) {
NS_ASSERTION(colSpan > 1,
"cell should not have been put in spanning cell sorter");
do {
int32_t row = item->row;
col = item->col;
CellData *cellData = cellMap->GetDataAt(row, col);
NS_ASSERTION(cellData && cellData->IsOrig(),
"bogus result from spanning cell sorter");
nsTableCellFrame *cellFrame = cellData->GetCellFrame();
NS_ASSERTION(cellFrame, "bogus result from spanning cell sorter");
CellISizeInfo info = GetCellISizeInfo(aRenderingContext, cellFrame, wm);
if (info.prefPercent > 0.0f) {
DistributePctISizeToColumns(info.prefPercent, col, colSpan);
}
DistributeISizeToColumns(info.minCoord, col, colSpan, BTLS_MIN_ISIZE,
info.hasSpecifiedISize);
DistributeISizeToColumns(info.prefCoord, col, colSpan, BTLS_PREF_ISIZE,
info.hasSpecifiedISize);
} while ((item = item->next));
// Combine the results of the span analysis into the main results,
// for each increment of colspan.
for (col = 0, col_end = cellMap->GetColCount(); col < col_end; ++col) {
nsTableColFrame *colFrame = tableFrame->GetColFrame(col);
if (!colFrame) {
NS_ERROR("column frames out of sync with cell map");
continue;
}
colFrame->AccumulateSpanIntrinsics();
colFrame->ResetSpanIntrinsics();
#ifdef DEBUG_dbaron_off
printf("table %p col %d span %d: min=%d pref=%d spec=%d pct=%f\n",
mTableFrame, col, colSpan, colFrame->GetMinCoord(),
colFrame->GetPrefCoord(), colFrame->GetHasSpecifiedCoord(),
colFrame->GetPrefPercent());
#endif
}
}
// Prevent percentages from adding to more than 100% by (to be
// compatible with other browsers) treating any percentages that would
// increase the total percentage to more than 100% as the number that
// would increase it to only 100% (which is 0% if we've already hit
// 100%). This means layout depends on the order of columns.
float pct_used = 0.0f;
for (col = 0, col_end = cellMap->GetColCount(); col < col_end; ++col) {
nsTableColFrame *colFrame = tableFrame->GetColFrame(col);
if (!colFrame) {
NS_ERROR("column frames out of sync with cell map");
continue;
}
colFrame->AdjustPrefPercent(&pct_used);
}
#ifdef DEBUG_TABLE_STRATEGY
printf("ComputeColumnIntrinsicISizes spanning\n");
mTableFrame->Dump(false, true, false);
#endif
}
void BasicTableLayoutStrategy::ComputeIntrinsicISizes(
gfxContext *aRenderingContext) {
ComputeColumnIntrinsicISizes(aRenderingContext);
nsTableCellMap *cellMap = mTableFrame->GetCellMap();
nscoord min = 0, pref = 0, max_small_pct_pref = 0, nonpct_pref_total = 0;
float pct_total = 0.0f; // always from 0.0f - 1.0f
int32_t colCount = cellMap->GetColCount();
// add a total of (colcount + 1) lots of cellSpacingX for columns where a
// cell originates
nscoord add = mTableFrame->GetColSpacing(colCount);
for (int32_t col = 0; col < colCount; ++col) {
nsTableColFrame *colFrame = mTableFrame->GetColFrame(col);
if (!colFrame) {
NS_ERROR("column frames out of sync with cell map");
continue;
}
if (mTableFrame->ColumnHasCellSpacingBefore(col)) {
add += mTableFrame->GetColSpacing(col - 1);
}
min += colFrame->GetMinCoord();
pref = NSCoordSaturatingAdd(pref, colFrame->GetPrefCoord());
// Percentages are of the table, so we have to reverse them for
// intrinsic isizes.
float p = colFrame->GetPrefPercent();
if (p > 0.0f) {
nscoord colPref = colFrame->GetPrefCoord();
nscoord new_small_pct_expand =
(colPref == nscoord_MAX ? nscoord_MAX : nscoord(float(colPref) / p));
if (new_small_pct_expand > max_small_pct_pref) {
max_small_pct_pref = new_small_pct_expand;
}
pct_total += p;
} else {
nonpct_pref_total =
NSCoordSaturatingAdd(nonpct_pref_total, colFrame->GetPrefCoord());
}
}
nscoord pref_pct_expand = pref;
// Account for small percentages expanding the preferred isize of
// *other* columns.
if (max_small_pct_pref > pref_pct_expand) {
pref_pct_expand = max_small_pct_pref;
}
// Account for large percentages expanding the preferred isize of
// themselves. There's no need to iterate over the columns multiple
// times, since when there is such a need, the small percentage
// effect is bigger anyway. (I think!)
NS_ASSERTION(0.0f <= pct_total && pct_total <= 1.0f,
"column percentage inline-sizes not adjusted down to 100%");
if (pct_total == 1.0f) {
if (nonpct_pref_total > 0) {
pref_pct_expand = nscoord_MAX;
// XXX Or should I use some smaller value? (Test this using
// nested tables!)
}
} else {
nscoord large_pct_pref =
(nonpct_pref_total == nscoord_MAX
? nscoord_MAX
: nscoord(float(nonpct_pref_total) / (1.0f - pct_total)));
if (large_pct_pref > pref_pct_expand) pref_pct_expand = large_pct_pref;
}
// border-spacing isn't part of the basis for percentages
if (colCount > 0) {
min += add;
pref = NSCoordSaturatingAdd(pref, add);
pref_pct_expand = NSCoordSaturatingAdd(pref_pct_expand, add);
}
mMinISize = min;
mPrefISize = pref;
mPrefISizePctExpand = pref_pct_expand;
}
/* virtual */ void BasicTableLayoutStrategy::MarkIntrinsicISizesDirty() {
mMinISize = NS_INTRINSIC_WIDTH_UNKNOWN;
mPrefISize = NS_INTRINSIC_WIDTH_UNKNOWN;
mPrefISizePctExpand = NS_INTRINSIC_WIDTH_UNKNOWN;
mLastCalcISize = nscoord_MIN;
}
/* virtual */ void BasicTableLayoutStrategy::ComputeColumnISizes(
const ReflowInput &aReflowInput) {
nscoord iSize = aReflowInput.ComputedISize();
if (mLastCalcISize == iSize) {
return;
}
mLastCalcISize = iSize;
NS_ASSERTION((mMinISize == NS_INTRINSIC_WIDTH_UNKNOWN) ==
(mPrefISize == NS_INTRINSIC_WIDTH_UNKNOWN),
"dirtyness out of sync");
NS_ASSERTION((mMinISize == NS_INTRINSIC_WIDTH_UNKNOWN) ==
(mPrefISizePctExpand == NS_INTRINSIC_WIDTH_UNKNOWN),
"dirtyness out of sync");
// XXX Is this needed?
if (mMinISize == NS_INTRINSIC_WIDTH_UNKNOWN) {
ComputeIntrinsicISizes(aReflowInput.mRenderingContext);
}
nsTableCellMap *cellMap = mTableFrame->GetCellMap();
int32_t colCount = cellMap->GetColCount();
if (colCount <= 0) return; // nothing to do
DistributeISizeToColumns(iSize, 0, colCount, BTLS_FINAL_ISIZE, false);
#ifdef DEBUG_TABLE_STRATEGY
printf("ComputeColumnISizes final\n");
mTableFrame->Dump(false, true, false);
#endif
}
void BasicTableLayoutStrategy::DistributePctISizeToColumns(float aSpanPrefPct,
int32_t aFirstCol,
int32_t aColCount) {
// First loop to determine:
int32_t nonPctColCount = 0; // number of spanned columns without % isize
nscoord nonPctTotalPrefISize = 0; // total pref isize of those columns
// and to reduce aSpanPrefPct by columns that already have % isize
int32_t scol, scol_end;
nsTableCellMap *cellMap = mTableFrame->GetCellMap();
for (scol = aFirstCol, scol_end = aFirstCol + aColCount; scol < scol_end;
++scol) {
nsTableColFrame *scolFrame = mTableFrame->GetColFrame(scol);
if (!scolFrame) {
NS_ERROR("column frames out of sync with cell map");
continue;
}
float scolPct = scolFrame->GetPrefPercent();
if (scolPct == 0.0f) {
nonPctTotalPrefISize += scolFrame->GetPrefCoord();
if (cellMap->GetNumCellsOriginatingInCol(scol) > 0) {
++nonPctColCount;
}
} else {
aSpanPrefPct -= scolPct;
}
}
if (aSpanPrefPct <= 0.0f || nonPctColCount == 0) {
// There's no %-isize on the colspan left over to distribute,
// or there are no columns to which we could distribute %-isize
return;
}
// Second loop, to distribute what remains of aSpanPrefPct
// between the non-percent-isize spanned columns
const bool spanHasNonPctPref = nonPctTotalPrefISize > 0; // Loop invariant
for (scol = aFirstCol, scol_end = aFirstCol + aColCount; scol < scol_end;
++scol) {
nsTableColFrame *scolFrame = mTableFrame->GetColFrame(scol);
if (!scolFrame) {
NS_ERROR("column frames out of sync with cell map");
continue;
}
if (scolFrame->GetPrefPercent() == 0.0f) {
NS_ASSERTION((!spanHasNonPctPref || nonPctTotalPrefISize != 0) &&
nonPctColCount != 0,
"should not be zero if we haven't allocated "
"all pref percent");
float allocatedPct; // % isize to be given to this column
if (spanHasNonPctPref) {
// Group so we're multiplying by 1.0f when we need
// to use up aSpanPrefPct.
allocatedPct = aSpanPrefPct * (float(scolFrame->GetPrefCoord()) /
float(nonPctTotalPrefISize));
} else if (cellMap->GetNumCellsOriginatingInCol(scol) > 0) {
// distribute equally when all pref isizes are 0
allocatedPct = aSpanPrefPct / float(nonPctColCount);
} else {
allocatedPct = 0.0f;
}
// Allocate the percent
scolFrame->AddSpanPrefPercent(allocatedPct);
// To avoid accumulating rounding error from division,
// subtract this column's values from the totals.
aSpanPrefPct -= allocatedPct;
nonPctTotalPrefISize -= scolFrame->GetPrefCoord();
if (cellMap->GetNumCellsOriginatingInCol(scol) > 0) {
--nonPctColCount;
}
if (!aSpanPrefPct) {
// No more span-percent-isize to distribute --> we're done.
NS_ASSERTION(
spanHasNonPctPref ? nonPctTotalPrefISize == 0 : nonPctColCount == 0,
"No more pct inline-size to distribute, "
"but there are still cols that need some.");
return;
}
}
}
}
void BasicTableLayoutStrategy::DistributeISizeToColumns(
nscoord aISize, int32_t aFirstCol, int32_t aColCount,
BtlsISizeType aISizeType, bool aSpanHasSpecifiedISize) {
NS_ASSERTION(
aISizeType != BTLS_FINAL_ISIZE ||
(aFirstCol == 0 &&
aColCount == mTableFrame->GetCellMap()->GetColCount()),
"Computing final column isizes, but didn't get full column range");
nscoord subtract = 0;
// aISize initially includes border-spacing for the boundaries in between
// each of the columns. We start at aFirstCol + 1 because the first
// in-between boundary would be at the left edge of column aFirstCol + 1
for (int32_t col = aFirstCol + 1; col < aFirstCol + aColCount; ++col) {
if (mTableFrame->ColumnHasCellSpacingBefore(col)) {
// border-spacing isn't part of the basis for percentages.
subtract += mTableFrame->GetColSpacing(col - 1);
}
}
if (aISizeType == BTLS_FINAL_ISIZE) {
// If we're computing final col-isize, then aISize initially includes
// border spacing on the table's far istart + far iend edge, too. Need
// to subtract those out, too.
subtract += (mTableFrame->GetColSpacing(-1) +
mTableFrame->GetColSpacing(aColCount));
}
aISize = NSCoordSaturatingSubtract(aISize, subtract, nscoord_MAX);
/*
* The goal of this function is to distribute |aISize| between the
* columns by making an appropriate AddSpanCoords or SetFinalISize
* call for each column. (We call AddSpanCoords if we're
* distributing a column-spanning cell's minimum or preferred isize
* to its spanned columns. We call SetFinalISize if we're
* distributing a table's final isize to its columns.)
*
* The idea is to either assign one of the following sets of isizes
* or a weighted average of two adjacent sets of isizes. It is not
* possible to assign values smaller than the smallest set of
* isizes. However, see below for handling the case of assigning
* values larger than the largest set of isizes. From smallest to
* largest, these are:
*
* 1. [guess_min] Assign all columns their min isize.
*
* 2. [guess_min_pct] Assign all columns with percentage isizes
* their percentage isize, and all other columns their min isize.
*
* 3. [guess_min_spec] Assign all columns with percentage isizes
* their percentage isize, all columns with specified coordinate
* isizes their pref isize (since it doesn't matter whether it's the
* largest contributor to the pref isize that was the specified
* contributor), and all other columns their min isize.
*
* 4. [guess_pref] Assign all columns with percentage isizes their
* specified isize, and all other columns their pref isize.
*
* If |aISize| is *larger* than what we would assign in (4), then we
* expand the columns:
*
* a. if any columns without a specified coordinate isize or
* percent isize have nonzero pref isize, in proportion to pref
* isize [total_flex_pref]
*
* b. otherwise, if any columns without a specified coordinate
* isize or percent isize, but with cells originating in them,
* have zero pref isize, equally between these
* [numNonSpecZeroISizeCols]
*
* c. otherwise, if any columns without percent isize have nonzero
* pref isize, in proportion to pref isize [total_fixed_pref]
*
* d. otherwise, if any columns have nonzero percentage isizes, in
* proportion to the percentage isizes [total_pct]
*
* e. otherwise, equally.
*/
// Loop #1 over the columns, to figure out the four values above so
// we know which case we're dealing with.
nscoord guess_min = 0, guess_min_pct = 0, guess_min_spec = 0, guess_pref = 0,
total_flex_pref = 0, total_fixed_pref = 0;
float total_pct = 0.0f; // 0.0f to 1.0f
int32_t numInfiniteISizeCols = 0;
int32_t numNonSpecZeroISizeCols = 0;
int32_t col;
nsTableCellMap *cellMap = mTableFrame->GetCellMap();
for (col = aFirstCol; col < aFirstCol + aColCount; ++col) {
nsTableColFrame *colFrame = mTableFrame->GetColFrame(col);
if (!colFrame) {
NS_ERROR("column frames out of sync with cell map");
continue;
}
nscoord min_iSize = colFrame->GetMinCoord();
guess_min += min_iSize;
if (colFrame->GetPrefPercent() != 0.0f) {
float pct = colFrame->GetPrefPercent();
total_pct += pct;
nscoord val = nscoord(float(aISize) * pct);
if (val < min_iSize) {
val = min_iSize;
}
guess_min_pct += val;
guess_pref = NSCoordSaturatingAdd(guess_pref, val);
} else {
nscoord pref_iSize = colFrame->GetPrefCoord();
if (pref_iSize == nscoord_MAX) {
++numInfiniteISizeCols;
}
guess_pref = NSCoordSaturatingAdd(guess_pref, pref_iSize);
guess_min_pct += min_iSize;
if (colFrame->GetHasSpecifiedCoord()) {
// we'll add on the rest of guess_min_spec outside the
// loop
nscoord delta = NSCoordSaturatingSubtract(pref_iSize, min_iSize, 0);
guess_min_spec = NSCoordSaturatingAdd(guess_min_spec, delta);
total_fixed_pref = NSCoordSaturatingAdd(total_fixed_pref, pref_iSize);
} else if (pref_iSize == 0) {
if (cellMap->GetNumCellsOriginatingInCol(col) > 0) {
++numNonSpecZeroISizeCols;
}
} else {
total_flex_pref = NSCoordSaturatingAdd(total_flex_pref, pref_iSize);
}
}
}
guess_min_spec = NSCoordSaturatingAdd(guess_min_spec, guess_min_pct);
// Determine what we're flexing:
enum Loop2Type {
FLEX_PCT_SMALL, // between (1) and (2) above
FLEX_FIXED_SMALL, // between (2) and (3) above
FLEX_FLEX_SMALL, // between (3) and (4) above
FLEX_FLEX_LARGE, // greater than (4) above, case (a)
FLEX_FLEX_LARGE_ZERO, // greater than (4) above, case (b)
FLEX_FIXED_LARGE, // greater than (4) above, case (c)
FLEX_PCT_LARGE, // greater than (4) above, case (d)
FLEX_ALL_LARGE // greater than (4) above, case (e)
};
Loop2Type l2t;
// These are constants (over columns) for each case's math. We use
// a pair of nscoords rather than a float so that we can subtract
// each column's allocation so we avoid accumulating rounding error.
nscoord space; // the amount of extra isize to allocate
union {
nscoord c;
float f;
} basis; // the sum of the statistic over columns to divide it
if (aISize < guess_pref) {
if (aISizeType != BTLS_FINAL_ISIZE && aISize <= guess_min) {
// Return early -- we don't have any extra space to distribute.
return;
}
NS_ASSERTION(!(aISizeType == BTLS_FINAL_ISIZE && aISize < guess_min),
"Table inline-size is less than the "
"sum of its columns' min inline-sizes");
if (aISize < guess_min_pct) {
l2t = FLEX_PCT_SMALL;
space = aISize - guess_min;
basis.c = guess_min_pct - guess_min;
} else if (aISize < guess_min_spec) {
l2t = FLEX_FIXED_SMALL;
space = aISize - guess_min_pct;
basis.c =
NSCoordSaturatingSubtract(guess_min_spec, guess_min_pct, nscoord_MAX);
} else {
l2t = FLEX_FLEX_SMALL;
space = aISize - guess_min_spec;
basis.c =
NSCoordSaturatingSubtract(guess_pref, guess_min_spec, nscoord_MAX);
}
} else {
space = NSCoordSaturatingSubtract(aISize, guess_pref, nscoord_MAX);
if (total_flex_pref > 0) {
l2t = FLEX_FLEX_LARGE;
basis.c = total_flex_pref;
} else if (numNonSpecZeroISizeCols > 0) {
l2t = FLEX_FLEX_LARGE_ZERO;
basis.c = numNonSpecZeroISizeCols;
} else if (total_fixed_pref > 0) {
l2t = FLEX_FIXED_LARGE;
basis.c = total_fixed_pref;
} else if (total_pct > 0.0f) {
l2t = FLEX_PCT_LARGE;
basis.f = total_pct;
} else {
l2t = FLEX_ALL_LARGE;
basis.c = aColCount;
}
}
#ifdef DEBUG_dbaron_off
printf(
"ComputeColumnISizes: %d columns in isize %d,\n"
" guesses=[%d,%d,%d,%d], totals=[%d,%d,%f],\n"
" l2t=%d, space=%d, basis.c=%d\n",
aColCount, aISize, guess_min, guess_min_pct, guess_min_spec, guess_pref,
total_flex_pref, total_fixed_pref, total_pct, l2t, space, basis.c);
#endif
for (col = aFirstCol; col < aFirstCol + aColCount; ++col) {
nsTableColFrame *colFrame = mTableFrame->GetColFrame(col);
if (!colFrame) {
NS_ERROR("column frames out of sync with cell map");
continue;
}
nscoord col_iSize;
float pct = colFrame->GetPrefPercent();
if (pct != 0.0f) {
col_iSize = nscoord(float(aISize) * pct);
nscoord col_min = colFrame->GetMinCoord();
if (col_iSize < col_min) {
col_iSize = col_min;
}
} else {
col_iSize = colFrame->GetPrefCoord();
}
nscoord col_iSize_before_adjust = col_iSize;
switch (l2t) {
case FLEX_PCT_SMALL:
col_iSize = col_iSize_before_adjust = colFrame->GetMinCoord();
if (pct != 0.0f) {
nscoord pct_minus_min = nscoord(float(aISize) * pct) - col_iSize;
if (pct_minus_min > 0) {
float c = float(space) / float(basis.c);
basis.c -= pct_minus_min;
col_iSize += NSToCoordRound(float(pct_minus_min) * c);
}
}
break;
case FLEX_FIXED_SMALL:
if (pct == 0.0f) {
NS_ASSERTION(col_iSize == colFrame->GetPrefCoord(),
"wrong inline-size assigned");
if (colFrame->GetHasSpecifiedCoord()) {
nscoord col_min = colFrame->GetMinCoord();
nscoord pref_minus_min = col_iSize - col_min;
col_iSize = col_iSize_before_adjust = col_min;
if (pref_minus_min != 0) {
float c = float(space) / float(basis.c);
basis.c -= pref_minus_min;
col_iSize += NSToCoordRound(float(pref_minus_min) * c);
}
} else
col_iSize = col_iSize_before_adjust = colFrame->GetMinCoord();
}
break;
case FLEX_FLEX_SMALL:
if (pct == 0.0f && !colFrame->GetHasSpecifiedCoord()) {
NS_ASSERTION(col_iSize == colFrame->GetPrefCoord(),
"wrong inline-size assigned");
nscoord col_min = colFrame->GetMinCoord();
nscoord pref_minus_min =
NSCoordSaturatingSubtract(col_iSize, col_min, 0);
col_iSize = col_iSize_before_adjust = col_min;
if (pref_minus_min != 0) {
float c = float(space) / float(basis.c);
// If we have infinite-isize cols, then the standard
// adjustment to col_iSize using 'c' won't work,
// because basis.c and pref_minus_min are both
// nscoord_MAX and will cancel each other out in the
// col_iSize adjustment (making us assign all the
// space to the first inf-isize col). To correct for
// this, we'll also divide by numInfiniteISizeCols to
// spread the space equally among the inf-isize cols.
if (numInfiniteISizeCols) {
if (colFrame->GetPrefCoord() == nscoord_MAX) {
c = c / float(numInfiniteISizeCols);
--numInfiniteISizeCols;
} else {
c = 0.0f;
}
}
basis.c =
NSCoordSaturatingSubtract(basis.c, pref_minus_min, nscoord_MAX);
col_iSize += NSToCoordRound(float(pref_minus_min) * c);
}
}
break;
case FLEX_FLEX_LARGE:
if (pct == 0.0f && !colFrame->GetHasSpecifiedCoord()) {
NS_ASSERTION(col_iSize == colFrame->GetPrefCoord(),
"wrong inline-size assigned");
if (col_iSize != 0) {
if (space == nscoord_MAX) {
basis.c -= col_iSize;
col_iSize = nscoord_MAX;
} else {
float c = float(space) / float(basis.c);
basis.c -= col_iSize;
col_iSize += NSToCoordRound(float(col_iSize) * c);
}
}
}
break;
case FLEX_FLEX_LARGE_ZERO:
if (pct == 0.0f && !colFrame->GetHasSpecifiedCoord() &&
cellMap->GetNumCellsOriginatingInCol(col) > 0) {
NS_ASSERTION(col_iSize == 0 && colFrame->GetPrefCoord() == 0,
"Since we're in FLEX_FLEX_LARGE_ZERO case, "
"all auto-inline-size cols should have zero "
"pref inline-size.");
float c = float(space) / float(basis.c);
col_iSize += NSToCoordRound(c);
--basis.c;
}
break;
case FLEX_FIXED_LARGE:
if (pct == 0.0f) {
NS_ASSERTION(col_iSize == colFrame->GetPrefCoord(),
"wrong inline-size assigned");
NS_ASSERTION(
colFrame->GetHasSpecifiedCoord() || colFrame->GetPrefCoord() == 0,
"wrong case");
if (col_iSize != 0) {
float c = float(space) / float(basis.c);
basis.c -= col_iSize;
col_iSize += NSToCoordRound(float(col_iSize) * c);
}
}
break;
case FLEX_PCT_LARGE:
NS_ASSERTION(pct != 0.0f || colFrame->GetPrefCoord() == 0,
"wrong case");
if (pct != 0.0f) {
float c = float(space) / basis.f;
col_iSize += NSToCoordRound(pct * c);
basis.f -= pct;
}
break;
case FLEX_ALL_LARGE: {
float c = float(space) / float(basis.c);
col_iSize += NSToCoordRound(c);
--basis.c;
} break;
}
// Only subtract from space if it's a real number.
if (space != nscoord_MAX) {
NS_ASSERTION(col_iSize != nscoord_MAX,
"How is col_iSize nscoord_MAX if space isn't?");
NS_ASSERTION(
col_iSize_before_adjust != nscoord_MAX,
"How is col_iSize_before_adjust nscoord_MAX if space isn't?");
space -= col_iSize - col_iSize_before_adjust;
}
NS_ASSERTION(col_iSize >= colFrame->GetMinCoord(),
"assigned inline-size smaller than min");
// Apply the new isize
switch (aISizeType) {
case BTLS_MIN_ISIZE: {
// Note: AddSpanCoords requires both a min and pref isize.
// For the pref isize, we'll just pass in our computed
// min isize, because the real pref isize will be at least
// as big
colFrame->AddSpanCoords(col_iSize, col_iSize, aSpanHasSpecifiedISize);
} break;
case BTLS_PREF_ISIZE: {
// Note: AddSpanCoords requires both a min and pref isize.
// For the min isize, we'll just pass in 0, because
// the real min isize will be at least 0
colFrame->AddSpanCoords(0, col_iSize, aSpanHasSpecifiedISize);
} break;
case BTLS_FINAL_ISIZE: {
nscoord old_final = colFrame->GetFinalISize();
colFrame->SetFinalISize(col_iSize);
if (old_final != col_iSize) {
mTableFrame->DidResizeColumns();
}
} break;
}
}
NS_ASSERTION(
(space == 0 || space == nscoord_MAX) &&
((l2t == FLEX_PCT_LARGE) ? (-0.001f < basis.f && basis.f < 0.001f)
: (basis.c == 0 || basis.c == nscoord_MAX)),
"didn't subtract all that we added");
}