/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
*/
#ifndef nsHTMLReflowState_h___
#define nsHTMLReflowState_h___
#include "nslayout.h"
class nsIFrame;
class nsIPresContext;
class nsIReflowCommand;
class nsIRenderingContext;
class nsISpaceManager;
class nsLineLayout;
struct nsStyleDisplay;
struct nsStylePosition;
struct nsStyleSpacing;
/**
* Constant used to indicate an unconstrained size.
*
* @see #Reflow()
*/
#define NS_UNCONSTRAINEDSIZE NS_MAXSIZE
/**
* The reason the frame is being reflowed.
*
* XXX Should probably be a #define so it can be extended for specialized
* reflow interfaces...
*
* @see nsHTMLReflowState
*/
enum nsReflowReason {
eReflowReason_Initial = 0, // initial reflow of a newly created frame
eReflowReason_Incremental = 1, // an incremental change has occured. see the reflow command for details
eReflowReason_Resize = 2, // general request to determine a desired size
eReflowReason_StyleChange = 3 // request to reflow because of a style change. Note: you must reflow
// all your child frames
};
/**
* CSS Frame type. Included as part of the reflow state.
*/
typedef PRUint32 nsCSSFrameType;
#define NS_CSS_FRAME_TYPE_UNKNOWN 0
#define NS_CSS_FRAME_TYPE_INLINE 1
#define NS_CSS_FRAME_TYPE_BLOCK 2 /* block-level in normal flow */
#define NS_CSS_FRAME_TYPE_FLOATING 3
#define NS_CSS_FRAME_TYPE_ABSOLUTE 4
#define NS_CSS_FRAME_TYPE_INTERNAL_TABLE 5 /* row group frame, row frame, cell frame, ... */
/**
* Bit-flag that indicates whether the element is replaced. Applies to inline,
* block-level, floating, and absolutely positioned elements
*/
#define NS_CSS_FRAME_TYPE_REPLACED 0x8000
/**
* Helper macros for telling whether items are replaced
*/
#define NS_FRAME_IS_REPLACED(_ft) \
(NS_CSS_FRAME_TYPE_REPLACED == ((_ft) & NS_CSS_FRAME_TYPE_REPLACED))
#define NS_FRAME_REPLACED(_ft) \
(NS_CSS_FRAME_TYPE_REPLACED | (_ft))
/**
* A macro to extract the type. Masks off the 'replaced' bit-flag
*/
#define NS_FRAME_GET_TYPE(_ft) \
((_ft) & ~NS_CSS_FRAME_TYPE_REPLACED)
#define NS_INTRINSICSIZE NS_UNCONSTRAINEDSIZE
#define NS_AUTOHEIGHT NS_UNCONSTRAINEDSIZE
#define NS_AUTOMARGIN NS_UNCONSTRAINEDSIZE
/**
* Reflow state passed to a frame during reflow. The reflow states are linked
* together. The availableWidth and availableHeight represent the available
* space in which to reflow your frame, and are computed based on the parent
* frame's computed width and computed height. The available space is the total
* space including margins, border, padding, and content area. A value of
* NS_UNCONSTRAINEDSIZE means you can choose whatever size you want
*
* @see #Reflow()
*/
struct nsHTMLReflowState {
// pointer to parent's reflow state
const nsHTMLReflowState* parentReflowState;
// the frame being reflowed
nsIFrame* frame;
// the reason for the reflow
nsReflowReason reason;
// the reflow command. only set for eReflowReason_Incremental
nsIReflowCommand* reflowCommand;
// the available space in which to reflow
nscoord availableWidth, availableHeight;
// rendering context to use for measurement
nsIRenderingContext* rendContext;
// is the current context at the top of a page?
PRPackedBool isTopOfPage;
// The type of frame, from css's perspective. This value is
// initialized by the Init method below.
nsCSSFrameType mFrameType;
nsISpaceManager* mSpaceManager;
// LineLayout object (only for inline reflow; set to NULL otherwise)
nsLineLayout* mLineLayout;
// The computed width specifies the frame's content width, and it does not
// apply to inline non-replaced elements
//
// For replaced inline frames, a value of NS_INTRINSICSIZE means you should
// use your intrinsic width as the computed width
//
// For block-level frames, the computed width is based on the width of the
// containing block, the margin/border/padding areas, and the min/max width
nscoord mComputedWidth;
// The computed height specifies the frame's content height, and it does
// not apply to inline non-replaced elements
//
// For replaced inline frames, a value of NS_INTRINSICSIZE means you should
// use your intrinsic height as the computed height
//
// For non-replaced block-level frames in the flow and floated, a value of
// NS_AUTOHEIGHT means you choose a height to shrink wrap around the normal
// flow child frames. The height must be within the limit of the min/max
// height if there is such a limit
//
// For replaced block-level frames, a value of NS_INTRINSICSIZE
// means you use your intrinsic height as the computed height
nscoord mComputedHeight;
// Computed margin values
nsMargin mComputedMargin;
// Cached copy of the border values
nsMargin mComputedBorderPadding;
// Computed padding values
nsMargin mComputedPadding;
// Computed values for 'left/top/right/bottom' offsets. Only applies to
// 'positioned' elements
nsMargin mComputedOffsets;
// Computed values for 'min-width/max-width' and 'min-height/max-height'
nscoord mComputedMinWidth, mComputedMaxWidth;
nscoord mComputedMinHeight, mComputedMaxHeight;
// Compact margin available space
nscoord mCompactMarginWidth;
// The following data members are relevant if nsStyleText.mTextAlign
// == NS_STYLE_TEXT_ALIGN_CHAR
// distance from reference edge (as specified in nsStyleDisplay.mDirection)
// to the align character (which will be specified in nsStyleTable)
nscoord mAlignCharOffset;
// if true, the reflow honors alignCharOffset and does not
// set it. if false, the reflow sets alignCharOffset
PRPackedBool mUseAlignCharOffset;
// Cached pointers to the various style structs used during intialization
const nsStyleDisplay* mStyleDisplay;
const nsStylePosition* mStylePosition;
const nsStyleSpacing* mStyleSpacing;
// This value keeps track of how deeply nested a given reflow state
// is from the top of the frame tree.
PRInt32 mReflowDepth;
// Note: The copy constructor is written by the compiler
// automatically. You can use that and then override specific values
// if you want, or you can call Init as desired...
// Initialize a root reflow state with a rendering context to
// use for measuring things.
nsHTMLReflowState(nsIPresContext* aPresContext,
nsIFrame* aFrame,
nsReflowReason aReason,
nsIRenderingContext* aRenderingContext,
const nsSize& aAvailableSpace);
// Initialize a root reflow state for an incremental
// reflow.
nsHTMLReflowState(nsIPresContext* aPresContext,
nsIFrame* aFrame,
nsIReflowCommand& aReflowCommand,
nsIRenderingContext* aRenderingContext,
const nsSize& aAvailableSpace);
// Initialize a reflow state for a child frames reflow. Some state
// is copied from the parent reflow state; the remaining state is
// computed.
nsHTMLReflowState(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace,
nsReflowReason aReason);
// Same as the previous except that the reason is taken from the
// parent's reflow state.
nsHTMLReflowState(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace);
// Used when you want to override the default containing block
// width and height. Used by absolute positioning code
nsHTMLReflowState(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight);
/**
* Get the containing block reflow state, starting from a frames
* parent reflow state (the parent reflow state may or may not end
* up being the containing block reflow state)
*/
static const nsHTMLReflowState*
GetContainingBlockReflowState(const nsHTMLReflowState* aParentRS);
/**
* First find the containing block's reflow state using
* GetContainingBlockReflowState, then ask the containing block for
* it's content width using GetContentWidth
*/
static nscoord
GetContainingBlockContentWidth(const nsHTMLReflowState* aParentRS);
/**
* Get the page box reflow state, starting from a frames
* parent reflow state (the parent reflow state may or may not end
* up being the containing block reflow state)
*/
static const nsHTMLReflowState*
GetPageBoxReflowState(const nsHTMLReflowState* aParentRS);
/**
* Compute the border plus padding for aFrame. If a
* percentage needs to be computed it will be computed by finding
* the containing block, use GetContainingBlockReflowState.
* aParentReflowState is aFrame's
* parent's reflow state. The resulting computed border plus padding
* is returned in aResult.
*/
static void ComputeBorderPaddingFor(nsIFrame* aFrame,
const nsHTMLReflowState* aParentRS,
nsMargin& aResult);
/**
* Calculate the raw line-height property for the given frame. The return
* value, if line-height was applied and is valid will be >= 0. Otherwise,
* the return value will be <0 which is illegal (CSS2 spec: section 10.8.1).
*/
static nscoord CalcLineHeight(nsIPresContext* aPresContext,
nsIRenderingContext* aRenderingContext,
nsIFrame* aFrame);
static PRBool UseComputedHeight();
static nsCSSFrameType DetermineFrameType(nsIFrame* aFrame);
void ComputeContainingBlockRectangle(const nsHTMLReflowState* aContainingBlockRS,
nscoord& aContainingBlockWidth,
nscoord& aContainingBlockHeight);
protected:
// This method initializes various data members. It is automatically
// called by the various constructors
void Init(nsIPresContext* aPresContext,
nscoord aContainingBlockWidth = -1,
nscoord aContainingBlockHeight = -1);
void InitConstraints(nsIPresContext* aPresContext,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight);
void InitAbsoluteConstraints(nsIPresContext* aPresContext,
const nsHTMLReflowState* cbrs,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight);
void ComputeRelativeOffsets(const nsHTMLReflowState* cbrs,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight);
void ComputeBlockBoxData(nsIPresContext* aPresContext,
const nsHTMLReflowState* cbrs,
nsStyleUnit aWidthUnit,
nsStyleUnit aHeightUnit,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight);
void CalculateBlockSideMargins(const nsHTMLReflowState* aContainingBlockRS,
nscoord aComputedWidth);
void ComputeHorizontalValue(nscoord aContainingBlockWidth,
nsStyleUnit aUnit,
const nsStyleCoord& aCoord,
nscoord& aResult);
void ComputeVerticalValue(nscoord aContainingBlockHeight,
nsStyleUnit aUnit,
const nsStyleCoord& aCoord,
nscoord& aResult);
static nsCSSFrameType DetermineFrameType(nsIFrame* aFrame,
const nsStylePosition* aPosition,
const nsStyleDisplay* aDisplay);
// Computes margin values from the specified margin style information, and
// fills in the mComputedMargin member
void ComputeMargin(nscoord aContainingBlockWidth,
const nsHTMLReflowState* aContainingBlockRS);
// Computes padding values from the specified padding style information, and
// fills in the mComputedPadding member
void ComputePadding(nscoord aContainingBlockWidth,
const nsHTMLReflowState* aContainingBlockRS);
// Calculates the computed values for the 'min-Width', 'max-Width',
// 'min-Height', and 'max-Height' properties, and stores them in the assorted
// data members
void ComputeMinMaxValues(nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
const nsHTMLReflowState* aContainingBlockRS);
};
#endif /* nsHTMLReflowState_h___ */