godot/thirdparty/graphite/include/graphite2/Segment.h
Rémi Verschelde 0ee6ffb257
graphite: Update to latest Git, switch to MIT license
Graphite is now available under:
MIT OR MPL-2.0 OR LGPL-2.1-or-later OR GPL-2.0-or-later

We pick MIT which is the same as Godot's main license for simplicity.

Remove define to skip deprecation warnings, upstream fixed those.
2022-12-13 10:06:00 +01:00

438 lines
19 KiB
C++

/* SPDX-License-Identifier: MIT OR MPL-2.0 OR LGPL-2.1-or-later OR GPL-2.0-or-later */
/* Copyright 2010, SIL International, All rights reserved. */
#pragma once
#include "graphite2/Types.h"
#include "graphite2/Font.h"
#ifdef __cplusplus
extern "C"
{
#endif
enum gr_break_weight {
gr_breakNone = 0,
/* after break weights */
gr_breakWhitespace = 10,
gr_breakWord = 15,
gr_breakIntra = 20,
gr_breakLetter = 30,
gr_breakClip = 40,
/* before break weights */
gr_breakBeforeWhitespace = -10,
gr_breakBeforeWord = -15,
gr_breakBeforeIntra = -20,
gr_breakBeforeLetter = -30,
gr_breakBeforeClip = -40
};
enum gr_justFlags {
/// Indicates that this segment is a complete line
gr_justCompleteLine = 0,
/// Indicates that the start of the slot list is not at the start of a line
gr_justStartInline = 1,
/// Indicates that the end of the slot list is not at the end of a line
gr_justEndInline = 2
};
/** Used for looking up slot attributes. Most are already available in other functions **/
enum gr_attrCode {
/// adjusted glyph advance in x direction in design units
gr_slatAdvX = 0,
/// adjusted glyph advance in y direction (usually 0) in design units
gr_slatAdvY,
/// returns 0. Deprecated.
gr_slatAttTo,
/// This slot attaches to its parent at the given design units in the x direction
gr_slatAttX,
/// This slot attaches to its parent at the given design units in the y direction
gr_slatAttY,
/// This slot attaches to its parent at the given glyph point (not implemented)
gr_slatAttGpt,
/// x-direction adjustment from the given glyph point (not implemented)
gr_slatAttXOff,
/// y-direction adjustment from the given glyph point (not implemented)
gr_slatAttYOff,
/// Where on this glyph should align with the attachment point on the parent glyph in the x-direction.
gr_slatAttWithX,
/// Where on this glyph should align with the attachment point on the parent glyph in the y-direction
gr_slatAttWithY,
/// Which glyph point on this glyph should align with the attachment point on the parent glyph (not implemented).
gr_slatWithGpt,
/// Adjustment to gr_slatWithGpt in x-direction (not implemented)
gr_slatAttWithXOff,
/// Adjustment to gr_slatWithGpt in y-direction (not implemented)
gr_slatAttWithYOff,
/// Attach at given nesting level (not implemented)
gr_slatAttLevel,
/// Line break breakweight for this glyph
gr_slatBreak,
/// Ligature component reference (not implemented)
gr_slatCompRef,
/// bidi directionality of this glyph (not implemented)
gr_slatDir,
/// Whether insertion is allowed before this glyph
gr_slatInsert,
/// Final positioned position of this glyph relative to its parent in x-direction in pixels
gr_slatPosX,
/// Final positioned position of this glyph relative to its parent in y-direction in pixels
gr_slatPosY,
/// Amount to shift glyph by in x-direction design units
gr_slatShiftX,
/// Amount to shift glyph by in y-direction design units
gr_slatShiftY,
/// attribute user1
gr_slatUserDefnV1,
/// not implemented
gr_slatMeasureSol,
/// not implemented
gr_slatMeasureEol,
/// Amount this slot can stretch (not implemented)
gr_slatJStretch,
/// Amount this slot can shrink (not implemented)
gr_slatJShrink,
/// Granularity by which this slot can stretch or shrink (not implemented)
gr_slatJStep,
/// Justification weight for this glyph (not implemented)
gr_slatJWeight,
/// Amount this slot mush shrink or stretch in design units
gr_slatJWidth = 29,
/// SubSegment split point
gr_slatSegSplit = gr_slatJStretch + 29,
/// User defined attribute, see subattr for user attr number
gr_slatUserDefn,
/// Bidi level
gr_slatBidiLevel = 56,
/// Collision flags
gr_slatColFlags,
/// Collision constraint rectangle left (bl.x)
gr_slatColLimitblx,
/// Collision constraint rectangle lower (bl.y)
gr_slatColLimitbly,
/// Collision constraint rectangle right (tr.x)
gr_slatColLimittrx,
/// Collision constraint rectangle upper (tr.y)
gr_slatColLimittry,
/// Collision shift x
gr_slatColShiftx,
/// Collision shift y
gr_slatColShifty,
/// Collision margin
gr_slatColMargin,
/// Margin cost weight
gr_slatColMarginWt,
// Additional glyph that excludes movement near this one:
gr_slatColExclGlyph,
gr_slatColExclOffx,
gr_slatColExclOffy,
// Collision sequence enforcing attributes:
gr_slatSeqClass,
gr_slatSeqProxClass,
gr_slatSeqOrder,
gr_slatSeqAboveXoff,
gr_slatSeqAboveWt,
gr_slatSeqBelowXlim,
gr_slatSeqBelowWt,
gr_slatSeqValignHt,
gr_slatSeqValignWt,
/// not implemented
gr_slatMax,
/// not implemented
gr_slatNoEffect = gr_slatMax + 1
};
enum gr_bidirtl {
/// Underlying paragraph direction is RTL
gr_rtl = 1,
/// Set this to not run the bidi pass internally, even if the font asks for it.
/// This presumes that the segment is in a single direction. Most of the time
/// this bit should be set unless you know you are passing full paragraphs of text.
gr_nobidi = 2,
/// Disable auto mirroring for rtl text
gr_nomirror = 4
};
typedef struct gr_char_info gr_char_info;
typedef struct gr_segment gr_segment;
typedef struct gr_slot gr_slot;
/** Returns Unicode character for a charinfo.
*
* @param p Pointer to charinfo to return information on.
*/
GR2_API unsigned int gr_cinfo_unicode_char(const gr_char_info* p/*not NULL*/);
/** Returns breakweight for a charinfo.
*
* @return Breakweight is a number between -50 and 50 indicating the cost of a
* break before or after this character. If the value < 0, the absolute value
* is this character's contribution to the overall breakweight before it. If the value
* > 0, then the value is this character's contribution to the overall breakweight after it.
* The overall breakweight between two characters is the maximum of the breakweight
* contributions from the characters either side of it. If a character makes no
* contribution to the breakweight on one side of it, the contribution is considered
* to be 0.
* @param p Pointer to charinfo to return information on.
*/
GR2_API int gr_cinfo_break_weight(const gr_char_info* p/*not NULL*/);
/** Returns the slot index that after this character is after in the slot stream
*
* In effect each character is associated with a set of slots and this returns
* the index of the last slot in the segment this character is associated with.
*
* @return after slot index between 0 and gr_seg_n_slots()
* @param p Pointer to charinfo to return information on.
*/
GR2_API int gr_cinfo_after(const gr_char_info* p/*not NULL*/);
/** Returns the slot index that before this character is before in the slot stream
*
* In effect each character is associated with a set of slots and this returns
* the index of the first slot in the segment this character is associated with.
*
* @return before slot index between 0 and gr_seg_n_slots()
* @param p Pointer to charinfo to return information on.
*/
GR2_API int gr_cinfo_before(const gr_char_info* p/*not NULL*/);
/** Returns the code unit index of this character in the input string
*
* @return code unit index between 0 and the end of the string
* @param p Pointer to charinfo to return information on.
*/
GR2_API size_t gr_cinfo_base(const gr_char_info* p/*not NULL*/);
/** Returns the number of unicode characters in a string.
*
* @return number of characters in the string
* @param enc Specifies the type of data in the string: utf8, utf16, utf32
* @param buffer_begin The start of the string
* @param buffer_end Measure up to the first nul or when end is reached, whichever is earliest.
* This parameter may be NULL.
* @param pError If there is a structural fault in the string, the location is returned
* in this variable. If no error occurs, pError will contain NULL. NULL
* may be passed for pError if no such information is required.
*/
GR2_API size_t gr_count_unicode_characters(enum gr_encform enc, const void* buffer_begin, const void* buffer_end, const void** pError);
/** Creates and returns a segment.
*
* @return a segment that needs seg_destroy called on it. May return NULL if bad problems
* in segment processing.
* @param font Gives the size of the font in pixels per em for final positioning. If
* NULL, positions are returned in design units, i.e. at a ppm of the upem
* of the face.
* @param face The face containing all the non-size dependent information.
* @param script This is a tag containing a script identifier that is used to choose
* which graphite table within the font to use. Maybe 0. Tag may be 4 chars
* NULL padded in LSBs or space padded in LSBs.
* @param pFeats Pointer to a feature values to be used for the segment. Only one
* feature values may be used for a segment. If NULL the default features
* for the font will be used.
* @param enc Specifies what encoding form the string is in (utf8, utf16, utf32)
* @param pStart Start of the string
* @param nChars Number of unicode characters to process in the string. The string will
* be processed either up to the first NULL or until nChars have been
* processed. nChars is also used to initialise the internal memory
* allocations of the segment. So it is wise not to make nChars too much
* greater than the actual number of characters being processed.
* @param dir Specifies whether the segment is processed right to left (1) or left to
* right (0) and whether to run the internal bidi pass, if a font requests it.
* See enum gr_bidirtl for details.
*/
GR2_API gr_segment* gr_make_seg(const gr_font* font, const gr_face* face, gr_uint32 script, const gr_feature_val* pFeats, enum gr_encform enc, const void* pStart, size_t nChars, int dir);
/** Destroys a segment, freeing the memory.
*
* @param p The segment to destroy
*/
GR2_API void gr_seg_destroy(gr_segment* p);
/** Returns the advance for the whole segment.
*
* Returns the width of the segment up to the next glyph origin after the segment
*/
GR2_API float gr_seg_advance_X(const gr_segment* pSeg/*not NULL*/);
/** Returns the height advance for the segment. **/
GR2_API float gr_seg_advance_Y(const gr_segment* pSeg/*not NULL*/);
/** Returns the number of gr_char_infos in the segment. **/
GR2_API unsigned int gr_seg_n_cinfo(const gr_segment* pSeg/*not NULL*/);
/** Returns a gr_char_info at a given index in the segment. **/
GR2_API const gr_char_info* gr_seg_cinfo(const gr_segment* pSeg/*not NULL*/, unsigned int index/*must be <number_of_CharInfo*/);
/** Returns the number of glyph gr_slots in the segment. **/
GR2_API unsigned int gr_seg_n_slots(const gr_segment* pSeg/*not NULL*/); //one slot per glyph
/** Returns the first gr_slot in the segment.
*
* The first slot in a segment has a gr_slot_prev_in_segment() of NULL. Slots are owned
* by their segment and are destroyed along with the segment.
*/
GR2_API const gr_slot* gr_seg_first_slot(gr_segment* pSeg/*not NULL*/); //may give a base slot or a slot which is attached to another
/** Returns the last gr_slot in the segment.
*
* The last slot in a segment has a gr_slot_next_in_segment() of NULL
*/
GR2_API const gr_slot* gr_seg_last_slot(gr_segment* pSeg/*not NULL*/); //may give a base slot or a slot which is attached to another
/** Justifies a linked list of slots for a line to a given width
*
* Passed a pointer to the start of a linked list of slots corresponding to a line, as
* set up by gr_slot_linebreak_before, this function will position the glyphs in the line
* to take up the given width. It is possible to specify a subrange within the line to process.
* This allows skipping of line initial or final whitespace, for example. While this will ensure
* that the subrange fits width, the line will still be positioned with the first glyph of the
* line at 0. So the resulting positions may be beyond width.
*
* @return float The resulting width of the range of slots justified.
* @param pSeg Pointer to the segment
* @param pStart Pointer to the start of the line linked list (including skipped characters)
* @param pFont Font to use for positioning
* @param width Width in pixels in which to fit the line. If < 0. don't adjust natural width, just run justification passes
* to handle line end contextuals, if there are any.
* @param flags Indicates line ending types. Default is linked list is a full line
* @param pFirst If not NULL, the first slot in the list to be considered part of the line (so can skip)
* @param pLast If not NULL, the last slot to process in the line (allow say trailing whitespace to be skipped)
*/
GR2_API float gr_seg_justify(gr_segment* pSeg/*not NULL*/, const gr_slot* pStart/*not NULL*/, const gr_font *pFont, double width, enum gr_justFlags flags, const gr_slot* pFirst, const gr_slot* pLast);
/** Returns the next slot along in the segment.
*
* Slots are held in a linked list. This returns the next in the linked list. The slot
* may or may not be attached to another slot. Returns NULL at the end of the segment.
*/
GR2_API const gr_slot* gr_slot_next_in_segment(const gr_slot* p);
/** Returns the previous slot along in the segment.
*
* Slots are held in a doubly linked list. This returns the previos slot in the linked
* list. This slot may or may not be attached to it. Returns NULL at the start of the
* segment.
*/
GR2_API const gr_slot* gr_slot_prev_in_segment(const gr_slot* p);
/** Returns the attachment parent slot of this slot.
*
* Attached slots form a tree. This returns the parent of this slot in that tree. A
* base glyph which is not attached to another glyph, always returns NULL.
*/
GR2_API const gr_slot* gr_slot_attached_to(const gr_slot* p);
/** Returns the first slot attached to this slot.
*
* Attached slots form a singly linked list from the parent. This returns the first
* slot in that list. Note that this is a reference to another slot that is also in
* the main segment doubly linked list.
*
* if gr_slot_first_attachment(p) != NULL then gr_slot_attached_to(gr_slot_first_attachment(p)) == p.
*/
GR2_API const gr_slot* gr_slot_first_attachment(const gr_slot* p);
/** Returns the next slot attached to our attachment parent.
*
* This returns the next slot in the singly linked list of slots attached to this
* slot's parent. If there are no more such slots, NULL is returned. If there is
* no parent, i.e. the passed slot is a cluster base, then the next cluster base
* in graphical order (ltr, even for rtl text) is returned.
*
* if gr_slot_next_sibling_attachment(p) != NULL then gr_slot_attached_to(gr_slot_next_sibling_attachment(p)) == gr_slot_attached_to(p).
*/
GR2_API const gr_slot* gr_slot_next_sibling_attachment(const gr_slot* p);
/** Returns glyph id of the slot
*
* Each slot has a glyphid which is rendered at the position given by the slot. This
* glyphid is the real glyph to be rendered and never a pseudo glyph.
*/
GR2_API unsigned short gr_slot_gid(const gr_slot* p);
/** Returns X offset of glyph from start of segment **/
GR2_API float gr_slot_origin_X(const gr_slot* p);
/** Returns Y offset of glyph from start of segment **/
GR2_API float gr_slot_origin_Y(const gr_slot* p);
/** Returns the glyph advance for this glyph as adjusted for kerning
*
* @param p Slot to give results for
* @param face gr_face of the glyphs. May be NULL if unhinted advances used
* @param font gr_font to scale for pixel results. If NULL returns design
* units advance. If not NULL then returns pixel advance based
* on hinted or scaled glyph advances in the font. face must be
* passed for hinted advances to be used.
*/
GR2_API float gr_slot_advance_X(const gr_slot* p, const gr_face* face, const gr_font *font);
/** Returns the vertical advance for the glyph in the slot adjusted for kerning
*
* Returns design units unless font is not NULL in which case the pixel value
* is returned scaled for the given font
*/
GR2_API float gr_slot_advance_Y(const gr_slot* p, const gr_face* face, const gr_font *font);
/** Returns the gr_char_info index before us
*
* Returns the index of the gr_char_info that a cursor before this slot, would put
* an underlying cursor before. This may also be interpretted as each slot holding
* a set of char_infos that it is associated with and this function returning the
* index of the char_info with lowest index, from this set.
*/
GR2_API int gr_slot_before(const gr_slot* p/*not NULL*/);
/** Returns the gr_char_info index after us
*
* Returns the index of the gr_char_info that a cursor after this slot would put an
* underlying cursor after. This may also be interpretted as each slot holding a set
* of char_infos that it is associated with and this function returning the index of
* the char_info with the highest index, from this set.
*/
GR2_API int gr_slot_after(const gr_slot* p/*not NULL*/);
/** Returns the index of this slot in the segment
*
* Returns the index given to this slot during final positioning. This corresponds
* to the value returned br gr_cinfo_before() and gr_cinfo_after()
*/
GR2_API unsigned int gr_slot_index(const gr_slot* p/*not NULL*/);
/** Return a slot attribute value
*
* Given a slot and an attribute along with a possible subattribute, return the
* corresponding value in the slot. See enum gr_attrCode for details of each attribute.
*/
GR2_API int gr_slot_attr(const gr_slot* p/*not NULL*/, const gr_segment* pSeg/*not NULL*/, enum gr_attrCode index, gr_uint8 subindex); //tbd - do we need to expose this?
/** Returns whether text may be inserted before this glyph.
*
* This indicates whether a cursor can be put before this slot. It applies to
* base glyphs that have no parent as well as attached glyphs that have the
* .insert attribute explicitly set to true. This is the primary mechanism
* for identifying contiguous sequences of base plus diacritics.
*/
GR2_API int gr_slot_can_insert_before(const gr_slot* p);
/** Returns the original gr_char_info index this slot refers to.
*
* Each Slot has a gr_char_info that it originates from. This is that gr_char_info.
* The index is passed to gr_seg_cinfo(). This information is useful for testing.
*/
GR2_API int gr_slot_original(const gr_slot* p/*not NULL*/);
/** Breaks a segment into lines.
*
* Breaks the slot linked list at the given point in the linked list. It is up
* to the application to keep track of the first slot on each line.
*/
GR2_API void gr_slot_linebreak_before(gr_slot *p/*not NULL*/);
#ifdef __cplusplus
}
#endif