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Moved vertical margin application into here; implement top-margin collapsing logic

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git-svn-id: svn://10.0.0.236/trunk@25293 18797224-902f-48f8-a5cc-f745e15eee43
This commit is contained in:
kipp%netscape.com
1999-03-27 01:22:45 +00:00
parent 72843bd8a8
commit 2d7802dd88
4 changed files with 224 additions and 182 deletions
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164
mozilla/layout/generic/nsBlockReflowContext.cpp
View File

@@ -24,15 +24,16 @@
#include "nsIPresContext.h"
#include "nsIStyleContext.h"
#include "nsHTMLContainerFrame.h"
#include "nsBlockFrame.h"
#ifdef NS_DEBUG
#undef NOISY_SPECULATIVE_TOP_MARGIN
#undef NOISY_MAX_ELEMENT_SIZE
#undef REALLY_NOISY_MAX_ELEMENT_SIZE
#undef NOISY_VERTICAL_MARGINS
#else
#undef NOISY_SPECULATIVE_TOP_MARGIN
#undef NOISY_MAX_ELEMENT_SIZE
#undef REALLY_NOISY_MAX_ELEMENT_SIZE
#undef NOISY_VERTICAL_MARGINS
#endif
nsBlockReflowContext::nsBlockReflowContext(nsIPresContext& aPresContext,
@@ -44,15 +45,67 @@ nsBlockReflowContext::nsBlockReflowContext(nsIPresContext& aPresContext,
{
mCompactMarginWidth = 0;
mStyleSpacing = nsnull;
#ifdef DEBUG
mIndent = 0;
#endif
}
nscoord
nsBlockReflowContext::ComputeCollapsedTopMargin(nsHTMLReflowState& aRS)
{
#ifdef NOISY_VERTICAL_MARGINS
mIndent++;
#endif
// Get aFrame's top margin
nscoord topMargin = aRS.computedMargin.top;
// Calculate aFrame's generational top-margin from its child
// blocks. Note that if aFrame has a non-zero top-border or
// top-padding then this step is skipped because it will be a margin
// root.
nscoord generationalTopMargin = 0;
if (0 == aRS.mComputedBorderPadding.top) {
nsBlockFrame* bf;
if (NS_SUCCEEDED(aRS.frame->QueryInterface(kBlockFrameCID, (void**)&bf))) {
// Ask the block frame for the top block child that we should
// try to collapse the top margin with.
nsIFrame* childFrame = bf->GetTopBlockChild();
if (nsnull != childFrame) {
// Here is where we recurse. Now that we have determined that a
// generational collapse is required we need to compute the
// child blocks margin and so in so that we can look into
// it. For its margins to be computed we need to have a reflow
// state for it.
nsSize availSpace(aRS.computedWidth, aRS.computedHeight);
nsHTMLReflowState reflowState(mPresContext, aRS, childFrame,
availSpace);
generationalTopMargin = ComputeCollapsedTopMargin(reflowState);
}
}
}
// Now compute the collapsed top-margin value. At this point we have
// the child frames effective top margin value.
nscoord collapsedTopMargin = MaxMargin(topMargin, generationalTopMargin);
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::IndentBy(stdout, mIndent);
nsFrame::ListTag(stdout, aRS.frame);
printf(": topMargin=%d generationalTopMargin=%d => %d\n",
topMargin, generationalTopMargin, collapsedTopMargin);
mIndent--;
#endif
return collapsedTopMargin;
}
nsresult
nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
const nsRect& aSpace,
#ifdef SPECULATIVE_TOP_MARGIN
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
#endif
PRBool aIsAdjacentWithTop,
nsMargin& aComputedOffsets,
nsReflowStatus& aFrameReflowStatus)
@@ -61,27 +114,6 @@ nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
mFrame = aFrame;
mSpace = aSpace;
#ifdef SPECULATIVE_TOP_MARGIN
#ifdef NOISY_SPECULATIVE_TOP_MARGIN
PRIntn pass = 0;
#endif
mSpeculativeTopMargin = 0;
if (aApplyTopMargin) {
// Compute a "speculative" collapsed top-margin value. Its
// speculative because we don't yet have the
// carried-out-top-margin value so the final collapsed value isn't
// knowable yet. We want to pre-apply the collapsed top-margin
// value so that when a block is flowing around floaters that we
// don't have to reflow it twice (we can't just slide it down when
// its flowing around a floater after discovering the final top
// margin value).
mSpeculativeTopMargin = MaxMargin(mMargin.top, aPrevBottomMargin);
}
again:
#else
mSpeculativeTopMargin = 0;
#endif
// Get reflow reason set correctly. It's possible that a child was
// created and then it was decided that it could not be reflowed
// (for example, a block frame that isn't at the start of a
@@ -100,6 +132,7 @@ nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
}
// Setup reflow state for reflowing the frame
// XXX subtract out vertical margin?
nsSize availSpace(aSpace.width, aSpace.height);
nsHTMLReflowState reflowState(mPresContext, mOuterReflowState, aFrame,
availSpace, reason);
@@ -111,13 +144,38 @@ nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
}
mIsTable = NS_STYLE_DISPLAY_TABLE == reflowState.mStyleDisplay->mDisplay;
nscoord topMargin = 0;
if (aApplyTopMargin) {
// Compute the childs collapsed top margin (its margin collpased
// with its first childs top-margin -- recursively).
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::ListTag(stdout, mOuterReflowState.frame);
printf(": prevBottomMargin=%d\n", aPrevBottomMargin);
#endif
topMargin = ComputeCollapsedTopMargin(reflowState);
// Collapse that value with the previous bottom margin to perform
// the sibling to sibling collaspe.
topMargin = MaxMargin(topMargin, aPrevBottomMargin);
// Adjust the available height if its constrained so that the
// child frame doesn't think it can reflow into its margin area.
// XXX write me
#if 0
availSpace.y += topMargin;
if (NS_UNCONSTRAINEDSIZE != availHeight) {
availSpace.height -= topMargin;
}
#endif
}
// Compute x/y coordinate where reflow will begin. Use the rules
// from 10.3.3 to determine what to apply. At this point in the
// reflow auto left/right margins will have a zero value.
mMargin = reflowState.computedMargin;
mStyleSpacing = reflowState.mStyleSpacing;
nscoord x = aSpace.x + mMargin.left;
nscoord y = aSpace.y + mSpeculativeTopMargin;
nscoord y = aSpace.y + topMargin;
mX = x;
mY = y;
@@ -244,31 +302,6 @@ nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
parent->DeleteChildsNextInFlow(mPresContext, aFrame);
}
}
#ifdef SPECULATIVE_TOP_MARGIN
if (aApplyTopMargin) {
// Compute final collapsed margin value
CollapseMargins(mMargin, mMetrics.mCarriedOutTopMargin,
mMetrics.mCarriedOutBottomMargin,
mMetrics.height, aPrevBottomMargin,
mTopMargin, mBottomMargin);
if (mSpeculativeTopMargin != mTopMargin) {
// We lost our speculative gamble. Use new computed margin
// value as the speculative value and try the reflow again.
#ifdef NOISY_SPECULATIVE_TOP_MARGIN
nsFrame::ListTag(stdout, mOuterReflowState.frame);
printf(": reflowing again: ");
nsFrame::ListTag(stdout, aFrame);
printf(" guess=%d actual=%d [pass %d]\n",
mSpeculativeTopMargin, mTopMargin, pass);
pass++;
#endif
mSpeculativeTopMargin = mTopMargin;
goto again;
}
}
#endif
}
return rv;
@@ -328,21 +361,15 @@ nsBlockReflowContext::CollapseMargins(const nsMargin& aMargin,
*/
PRBool
nsBlockReflowContext::PlaceBlock(PRBool aForceFit,
#ifndef SPECULATIVE_TOP_MARGIN
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
#endif
const nsMargin& aComputedOffsets,
nscoord* aBottomMarginResult,
nsRect& aInFlowBounds,
nsRect& aCombinedRect)
{
#ifndef SPECULATIVE_TOP_MARGIN
// Compute final collapsed margin value
CollapseMargins(mMargin, mMetrics.mCarriedOutTopMargin,
mMetrics.mCarriedOutBottomMargin,
mMetrics.height, aPrevBottomMargin,
mTopMargin, mBottomMargin);
#endif
// Compute collapsed bottom margin value
nscoord collapsedBottomMargin = MaxMargin(mMetrics.mCarriedOutBottomMargin,
mMargin.bottom);
*aBottomMarginResult = collapsedBottomMargin;
// See if the block will fit in the available space
PRBool fits = PR_TRUE;
@@ -354,20 +381,13 @@ nsBlockReflowContext::PlaceBlock(PRBool aForceFit,
nsRect r(x, y, 0, 0);
mFrame->SetRect(r);
aInFlowBounds = r;
// Retain combined area information in case we contain a floater
// and nothing else.
aCombinedRect = mMetrics.mCombinedArea;
aCombinedRect.x += x;
aCombinedRect.y += y;
mTopMargin = 0;
mBottomMargin = 0;
}
else {
// Apply top margin unless it's going to be carried out.
#ifndef SPECULATIVE_TOP_MARGIN
if (aApplyTopMargin) {
y += mTopMargin;
}
#endif
// See if the frame fit. If its the first frame then it always
// fits.
if (aForceFit || (y + mMetrics.height <= mSpace.YMost())) {
@@ -501,9 +521,11 @@ nsBlockReflowContext::PlaceBlock(PRBool aForceFit,
m->width += mMargin.right;
}
#if XXX_fix_me
// Margin height should affect the max-element height (since
// auto top/bottom margins are always zero)
m->height += mTopMargin + mBottomMargin;
#endif
}
}
else {

39
mozilla/layout/generic/nsBlockReflowContext.h
View File

@@ -28,8 +28,6 @@ class nsLineLayout;
struct nsStylePosition;
struct nsStyleSpacing;
#undef SPECULATIVE_TOP_MARGIN
/**
* An encapsulation of the state and algorithm for reflowing block frames.
*/
@@ -54,34 +52,29 @@ public:
nsresult ReflowBlock(nsIFrame* aFrame,
const nsRect& aSpace,
#ifdef SPECULATIVE_TOP_MARGIN
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
#endif
PRBool aIsAdjacentWithTop,
nsMargin& aComputedOffsets,
nsReflowStatus& aReflowStatus);
PRBool PlaceBlock(PRBool aForceFit,
#ifndef SPECULATIVE_TOP_MARGIN
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
#endif
const nsMargin& aComputedOffsets,
nscoord* aBottomMarginResult,
nsRect& aInFlowBounds,
nsRect& aCombinedRect);
nscoord GetCollapsedTopMargin() const {
return mTopMargin;
}
//XXX nscoord GetCollapsedTopMargin() const {
//XXX return mTopMargin;
//XXX }
nscoord GetCollapsedBottomMargin() const {
return mBottomMargin;
}
//XXX nscoord GetCollapsedBottomMargin() const {
//XXX return mBottomMargin;
//XXX }
nscoord GetCarriedOutTopMargin() const {
return mMetrics.mCarriedOutTopMargin;
}
//XXX nscoord GetCarriedOutTopMargin() const {
//XXX return mMetrics.mCarriedOutTopMargin;
//XXX }
nscoord GetCarriedOutBottomMargin() const {
return mMetrics.mCarriedOutBottomMargin;
@@ -138,11 +131,17 @@ protected:
nsMargin mMargin;
nscoord mX, mY;
nsHTMLReflowMetrics mMetrics;
nscoord mSpeculativeTopMargin;
nscoord mTopMargin;
nscoord mBottomMargin;
//XXX nscoord mSpeculativeTopMargin;
//XXX nscoord mTopMargin;
//XXX nscoord mBottomMargin;
nsSize mMaxElementSize;
PRBool mIsTable;
#ifdef DEBUG
PRInt32 mIndent;
#endif
nscoord ComputeCollapsedTopMargin(nsHTMLReflowState& aRS);
};
#endif /* nsBlockReflowContext_h___ */

164
mozilla/layout/html/base/src/nsBlockReflowContext.cpp
View File

@@ -24,15 +24,16 @@
#include "nsIPresContext.h"
#include "nsIStyleContext.h"
#include "nsHTMLContainerFrame.h"
#include "nsBlockFrame.h"
#ifdef NS_DEBUG
#undef NOISY_SPECULATIVE_TOP_MARGIN
#undef NOISY_MAX_ELEMENT_SIZE
#undef REALLY_NOISY_MAX_ELEMENT_SIZE
#undef NOISY_VERTICAL_MARGINS
#else
#undef NOISY_SPECULATIVE_TOP_MARGIN
#undef NOISY_MAX_ELEMENT_SIZE
#undef REALLY_NOISY_MAX_ELEMENT_SIZE
#undef NOISY_VERTICAL_MARGINS
#endif
nsBlockReflowContext::nsBlockReflowContext(nsIPresContext& aPresContext,
@@ -44,15 +45,67 @@ nsBlockReflowContext::nsBlockReflowContext(nsIPresContext& aPresContext,
{
mCompactMarginWidth = 0;
mStyleSpacing = nsnull;
#ifdef DEBUG
mIndent = 0;
#endif
}
nscoord
nsBlockReflowContext::ComputeCollapsedTopMargin(nsHTMLReflowState& aRS)
{
#ifdef NOISY_VERTICAL_MARGINS
mIndent++;
#endif
// Get aFrame's top margin
nscoord topMargin = aRS.computedMargin.top;
// Calculate aFrame's generational top-margin from its child
// blocks. Note that if aFrame has a non-zero top-border or
// top-padding then this step is skipped because it will be a margin
// root.
nscoord generationalTopMargin = 0;
if (0 == aRS.mComputedBorderPadding.top) {
nsBlockFrame* bf;
if (NS_SUCCEEDED(aRS.frame->QueryInterface(kBlockFrameCID, (void**)&bf))) {
// Ask the block frame for the top block child that we should
// try to collapse the top margin with.
nsIFrame* childFrame = bf->GetTopBlockChild();
if (nsnull != childFrame) {
// Here is where we recurse. Now that we have determined that a
// generational collapse is required we need to compute the
// child blocks margin and so in so that we can look into
// it. For its margins to be computed we need to have a reflow
// state for it.
nsSize availSpace(aRS.computedWidth, aRS.computedHeight);
nsHTMLReflowState reflowState(mPresContext, aRS, childFrame,
availSpace);
generationalTopMargin = ComputeCollapsedTopMargin(reflowState);
}
}
}
// Now compute the collapsed top-margin value. At this point we have
// the child frames effective top margin value.
nscoord collapsedTopMargin = MaxMargin(topMargin, generationalTopMargin);
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::IndentBy(stdout, mIndent);
nsFrame::ListTag(stdout, aRS.frame);
printf(": topMargin=%d generationalTopMargin=%d => %d\n",
topMargin, generationalTopMargin, collapsedTopMargin);
mIndent--;
#endif
return collapsedTopMargin;
}
nsresult
nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
const nsRect& aSpace,
#ifdef SPECULATIVE_TOP_MARGIN
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
#endif
PRBool aIsAdjacentWithTop,
nsMargin& aComputedOffsets,
nsReflowStatus& aFrameReflowStatus)
@@ -61,27 +114,6 @@ nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
mFrame = aFrame;
mSpace = aSpace;
#ifdef SPECULATIVE_TOP_MARGIN
#ifdef NOISY_SPECULATIVE_TOP_MARGIN
PRIntn pass = 0;
#endif
mSpeculativeTopMargin = 0;
if (aApplyTopMargin) {
// Compute a "speculative" collapsed top-margin value. Its
// speculative because we don't yet have the
// carried-out-top-margin value so the final collapsed value isn't
// knowable yet. We want to pre-apply the collapsed top-margin
// value so that when a block is flowing around floaters that we
// don't have to reflow it twice (we can't just slide it down when
// its flowing around a floater after discovering the final top
// margin value).
mSpeculativeTopMargin = MaxMargin(mMargin.top, aPrevBottomMargin);
}
again:
#else
mSpeculativeTopMargin = 0;
#endif
// Get reflow reason set correctly. It's possible that a child was
// created and then it was decided that it could not be reflowed
// (for example, a block frame that isn't at the start of a
@@ -100,6 +132,7 @@ nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
}
// Setup reflow state for reflowing the frame
// XXX subtract out vertical margin?
nsSize availSpace(aSpace.width, aSpace.height);
nsHTMLReflowState reflowState(mPresContext, mOuterReflowState, aFrame,
availSpace, reason);
@@ -111,13 +144,38 @@ nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
}
mIsTable = NS_STYLE_DISPLAY_TABLE == reflowState.mStyleDisplay->mDisplay;
nscoord topMargin = 0;
if (aApplyTopMargin) {
// Compute the childs collapsed top margin (its margin collpased
// with its first childs top-margin -- recursively).
#ifdef NOISY_VERTICAL_MARGINS
nsFrame::ListTag(stdout, mOuterReflowState.frame);
printf(": prevBottomMargin=%d\n", aPrevBottomMargin);
#endif
topMargin = ComputeCollapsedTopMargin(reflowState);
// Collapse that value with the previous bottom margin to perform
// the sibling to sibling collaspe.
topMargin = MaxMargin(topMargin, aPrevBottomMargin);
// Adjust the available height if its constrained so that the
// child frame doesn't think it can reflow into its margin area.
// XXX write me
#if 0
availSpace.y += topMargin;
if (NS_UNCONSTRAINEDSIZE != availHeight) {
availSpace.height -= topMargin;
}
#endif
}
// Compute x/y coordinate where reflow will begin. Use the rules
// from 10.3.3 to determine what to apply. At this point in the
// reflow auto left/right margins will have a zero value.
mMargin = reflowState.computedMargin;
mStyleSpacing = reflowState.mStyleSpacing;
nscoord x = aSpace.x + mMargin.left;
nscoord y = aSpace.y + mSpeculativeTopMargin;
nscoord y = aSpace.y + topMargin;
mX = x;
mY = y;
@@ -244,31 +302,6 @@ nsBlockReflowContext::ReflowBlock(nsIFrame* aFrame,
parent->DeleteChildsNextInFlow(mPresContext, aFrame);
}
}
#ifdef SPECULATIVE_TOP_MARGIN
if (aApplyTopMargin) {
// Compute final collapsed margin value
CollapseMargins(mMargin, mMetrics.mCarriedOutTopMargin,
mMetrics.mCarriedOutBottomMargin,
mMetrics.height, aPrevBottomMargin,
mTopMargin, mBottomMargin);
if (mSpeculativeTopMargin != mTopMargin) {
// We lost our speculative gamble. Use new computed margin
// value as the speculative value and try the reflow again.
#ifdef NOISY_SPECULATIVE_TOP_MARGIN
nsFrame::ListTag(stdout, mOuterReflowState.frame);
printf(": reflowing again: ");
nsFrame::ListTag(stdout, aFrame);
printf(" guess=%d actual=%d [pass %d]\n",
mSpeculativeTopMargin, mTopMargin, pass);
pass++;
#endif
mSpeculativeTopMargin = mTopMargin;
goto again;
}
}
#endif
}
return rv;
@@ -328,21 +361,15 @@ nsBlockReflowContext::CollapseMargins(const nsMargin& aMargin,
*/
PRBool
nsBlockReflowContext::PlaceBlock(PRBool aForceFit,
#ifndef SPECULATIVE_TOP_MARGIN
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
#endif
const nsMargin& aComputedOffsets,
nscoord* aBottomMarginResult,
nsRect& aInFlowBounds,
nsRect& aCombinedRect)
{
#ifndef SPECULATIVE_TOP_MARGIN
// Compute final collapsed margin value
CollapseMargins(mMargin, mMetrics.mCarriedOutTopMargin,
mMetrics.mCarriedOutBottomMargin,
mMetrics.height, aPrevBottomMargin,
mTopMargin, mBottomMargin);
#endif
// Compute collapsed bottom margin value
nscoord collapsedBottomMargin = MaxMargin(mMetrics.mCarriedOutBottomMargin,
mMargin.bottom);
*aBottomMarginResult = collapsedBottomMargin;
// See if the block will fit in the available space
PRBool fits = PR_TRUE;
@@ -354,20 +381,13 @@ nsBlockReflowContext::PlaceBlock(PRBool aForceFit,
nsRect r(x, y, 0, 0);
mFrame->SetRect(r);
aInFlowBounds = r;
// Retain combined area information in case we contain a floater
// and nothing else.
aCombinedRect = mMetrics.mCombinedArea;
aCombinedRect.x += x;
aCombinedRect.y += y;
mTopMargin = 0;
mBottomMargin = 0;
}
else {
// Apply top margin unless it's going to be carried out.
#ifndef SPECULATIVE_TOP_MARGIN
if (aApplyTopMargin) {
y += mTopMargin;
}
#endif
// See if the frame fit. If its the first frame then it always
// fits.
if (aForceFit || (y + mMetrics.height <= mSpace.YMost())) {
@@ -501,9 +521,11 @@ nsBlockReflowContext::PlaceBlock(PRBool aForceFit,
m->width += mMargin.right;
}
#if XXX_fix_me
// Margin height should affect the max-element height (since
// auto top/bottom margins are always zero)
m->height += mTopMargin + mBottomMargin;
#endif
}
}
else {

39
mozilla/layout/html/base/src/nsBlockReflowContext.h
View File

@@ -28,8 +28,6 @@ class nsLineLayout;
struct nsStylePosition;
struct nsStyleSpacing;
#undef SPECULATIVE_TOP_MARGIN
/**
* An encapsulation of the state and algorithm for reflowing block frames.
*/
@@ -54,34 +52,29 @@ public:
nsresult ReflowBlock(nsIFrame* aFrame,
const nsRect& aSpace,
#ifdef SPECULATIVE_TOP_MARGIN
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
#endif
PRBool aIsAdjacentWithTop,
nsMargin& aComputedOffsets,
nsReflowStatus& aReflowStatus);
PRBool PlaceBlock(PRBool aForceFit,
#ifndef SPECULATIVE_TOP_MARGIN
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
#endif
const nsMargin& aComputedOffsets,
nscoord* aBottomMarginResult,
nsRect& aInFlowBounds,
nsRect& aCombinedRect);
nscoord GetCollapsedTopMargin() const {
return mTopMargin;
}
//XXX nscoord GetCollapsedTopMargin() const {
//XXX return mTopMargin;
//XXX }
nscoord GetCollapsedBottomMargin() const {
return mBottomMargin;
}
//XXX nscoord GetCollapsedBottomMargin() const {
//XXX return mBottomMargin;
//XXX }
nscoord GetCarriedOutTopMargin() const {
return mMetrics.mCarriedOutTopMargin;
}
//XXX nscoord GetCarriedOutTopMargin() const {
//XXX return mMetrics.mCarriedOutTopMargin;
//XXX }
nscoord GetCarriedOutBottomMargin() const {
return mMetrics.mCarriedOutBottomMargin;
@@ -138,11 +131,17 @@ protected:
nsMargin mMargin;
nscoord mX, mY;
nsHTMLReflowMetrics mMetrics;
nscoord mSpeculativeTopMargin;
nscoord mTopMargin;
nscoord mBottomMargin;
//XXX nscoord mSpeculativeTopMargin;
//XXX nscoord mTopMargin;
//XXX nscoord mBottomMargin;
nsSize mMaxElementSize;
PRBool mIsTable;
#ifdef DEBUG
PRInt32 mIndent;
#endif
nscoord ComputeCollapsedTopMargin(nsHTMLReflowState& aRS);
};
#endif /* nsBlockReflowContext_h___ */