inkscape/src/style.h

	style.h revision 74ba6bbc2af90e342434b2a1b7a65bfe70f9d33f
#ifndef __SP_STYLE_H__
#define __SP_STYLE_H__

/** \file
 * SPStyle - a style object for SPItem objects
 *
 * Authors:
 *   Lauris Kaplinski <lauris@kaplinski.com>
 *
 * Copyright (C) 2001-2002 Lauris Kaplinski
 * Copyright (C) 2001 Ximian, Inc.
 *
 * Released under GNU GPL, read the file 'COPYING' for more information
 */

#include "color.h"
#include "forward.h"
#include "sp-marker-loc.h"

namespace Inkscape {
namespace XML {
class Node;
}
}

class SPCSSAttr;

namespace Inkscape {
gchar *parse_css_url(gchar const *string);
}

class SPIFloat;
class SPIScale24;
class SPIInt;
class SPIShort;
class SPIEnum;
class SPIString;
class SPILength;
class SPIPaint;
class SPIFontSize;

/// Float type internal to SPStyle.
struct SPIFloat {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned data : 30;
    float value;
};

/*
 * One might think that the best value for SP_SCALE24_MAX would be ((1<<24)-1), which allows the
 * greatest possible precision for fitting [0, 1] fractions into 24 bits.
 *
 * However, in practice, that gives a problem with 0.5, which falls half way between two fractions
 * of ((1<<24)-1).  What's worse is that casting double(1<<23) / ((1<<24)-1) to float on x86
 * produces wrong rounding behaviour, resulting in a fraction of ((1<<23)+2.0f) / (1<<24) rather
 * than ((1<<23)+1.0f) / (1<<24) as one would expect, let alone ((1<<23)+0.0f) / (1<<24) as one
 * would ideally like for this example.
 *
 * The value (1<<23) is thus best if one considers float conversions alone.
 *
 * The value 0xff0000 can exactly represent all 8-bit alpha channel values,
 * and can exactly represent all multiples of 0.1.  I haven't yet tested whether
 * rounding bugs still get in the way of conversions to & from float, but my instinct is that
 * it's fairly safe because 0xff fits three times inside float's significand.
 *
 * We should probably use the value 0xffff00 once we support 16 bits per channel and/or LittleCMS,
 * though that might need to be accompanied by greater use of double instead of float for
 * colours and opacities, to be safe from rounding bugs.
 */
#define SP_SCALE24_MAX (0xff0000)
#define SP_SCALE24_TO_FLOAT(v) ((double) (v) / SP_SCALE24_MAX)
#define SP_SCALE24_FROM_FLOAT(v) unsigned(((v) * SP_SCALE24_MAX) + .5)

/** Returns a scale24 for the product of two scale24 values. */
#define SP_SCALE24_MUL(_v1, _v2) unsigned((double)(_v1) * (_v2) / SP_SCALE24_MAX + .5)

/// 24 bit data type internal to SPStyle.
struct SPIScale24 {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned value : 24;
};

/// Int type internal to SPStyle.
struct SPIInt {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned data : 30;
    int value;
};

/// Short type internal to SPStyle.
struct SPIShort {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned data : 14;
    int value : 16;
};

/// Enum type internal to SPStyle.
struct SPIEnum {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned value : 8;
    unsigned computed : 8;
};

/// String type internal to SPStyle.
struct SPIString {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned data : 30;
    gchar *value;
};

enum {
    SP_CSS_UNIT_NONE,
    SP_CSS_UNIT_PX,
    SP_CSS_UNIT_PT,
    SP_CSS_UNIT_PC,
    SP_CSS_UNIT_MM,
    SP_CSS_UNIT_CM,
    SP_CSS_UNIT_IN,
    SP_CSS_UNIT_EM,
    SP_CSS_UNIT_EX,
    SP_CSS_UNIT_PERCENT
};

/// Length type internal to SPStyle.
struct SPILength {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned unit : 4;
    float value;
    float computed;
};

#define SP_STYLE_FILL_SERVER(s) (((SPStyle *) (s))->fill.value.paint.server)
#define SP_STYLE_STROKE_SERVER(s) (((SPStyle *) (s))->stroke.value.paint.server)
#define SP_OBJECT_STYLE_FILL_SERVER(o) (SP_OBJECT (o)->style->fill.value.paint.server)
#define SP_OBJECT_STYLE_STROKE_SERVER(o) (SP_OBJECT (o)->style->stroke.value.paint.server)

enum {
    SP_PAINT_TYPE_NONE,
    SP_PAINT_TYPE_COLOR,
    SP_PAINT_TYPE_PAINTSERVER,
    SP_PAINT_TYPE_IMPOSSIBLE
};

/// Paint type internal to SPStyle.
struct SPIPaint {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned currentcolor : 1;
    unsigned type : 2;
    union {
        SPColor color;
        struct {
            SPPaintServer *server;
            gchar *uri;
        } paint;
    } value;
};

enum {
    SP_FONT_SIZE_LITERAL,
    SP_FONT_SIZE_LENGTH,
    SP_FONT_SIZE_PERCENTAGE
};

#define SP_FONT_SIZE ((1 << 24) - 1)

#define SP_F8_16_TO_FLOAT(v) ((gdouble) (v) / (1 << 16))
#define SP_F8_16_FROM_FLOAT(v) ((int) ((v) * ((1 << 16) + 0.9999)))

#define SP_STYLE_FLAG_IFSET (1 << 0)
#define SP_STYLE_FLAG_IFDIFF (1 << 1)
#define SP_STYLE_FLAG_ALWAYS (1 << 2)

/// Fontsize type internal to SPStyle.
struct SPIFontSize {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned type : 2;
    unsigned value : 24;
    float computed;
};

/// Text decoration type internal to SPStyle.
struct SPITextDecoration {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned underline : 1;
    unsigned overline : 1;
    unsigned line_through : 1;
    unsigned blink : 1;    // "Conforming user agents are not required to support this value." yay!
};

/// Extended length type internal to SPStyle.
struct SPILengthOrNormal {
    unsigned set : 1;
    unsigned inherit : 1;
    unsigned normal : 1;
    unsigned unit : 4;
    float value;
    float computed;
};

class SPTextStyle;

/// Stroke dash details.
class NRVpathDash {
public:
    double offset;
    int n_dash;
    double *dash;
};

/// An SVG style object.
struct SPStyle {
    int refcount;
    /** Object we are attached to */
    SPObject *object;
    /** Our text style component */
    SPTextStyle *text;
    unsigned text_private : 1;

    /* CSS2 */
    /* Font */
    /** Size of the font */
    SPIFontSize font_size;
    /** Style of the font */
    SPIEnum font_style;
    /** Which substyle of the font */
    SPIEnum font_variant;
    /** Weight of the font */
    SPIEnum font_weight;
    /** Stretch of the font */
    SPIEnum font_stretch;

    /** First line indent of paragraphs (css2 16.1) */
    SPILength text_indent;
    /** text alignment (css2 16.2) (not to be confused with text-anchor) */
    SPIEnum text_align;
    /** text decoration (css2 16.3.1) */
    SPITextDecoration text_decoration;
    // 16.3.2 is text-shadow. That's complicated.
    /** Line spacing (css2 10.8.1) */
    SPILengthOrNormal line_height;
    /** letter spacing (css2 16.4) */
    SPILengthOrNormal letter_spacing;
    /** word spacing (also css2 16.4) */
    SPILengthOrNormal word_spacing;
    /** capitalization (css2 16.5) */
    SPIEnum text_transform;

    /* CSS3 Text */
    /** text direction (css3 text 3.2) */
    SPIEnum direction;
    /** block progression (css3 text 3.2) */
    SPIEnum block_progression;
    /** Writing mode (css3 text 3.2 and svg1.1 10.7.2) */
    SPIEnum writing_mode;

    /* SVG */
    /** Anchor of the text (svg1.1 10.9.1) */
    SPIEnum text_anchor;

    /* Misc attributes */
    unsigned clip_set : 1;
    unsigned color_set : 1;
    unsigned cursor_set : 1;
    unsigned overflow_set : 1;
    unsigned clip_path_set : 1;
    unsigned clip_rule_set : 1;
    unsigned mask_set : 1;

    /** display */
    SPIEnum display;

    /** overflow */
    SPIEnum overflow;

    /** visibility */
    SPIEnum visibility;

    /** opacity */
    SPIScale24 opacity;

    /** color */
    SPIPaint color;

    /** fill */
    SPIPaint fill;
    /** fill-opacity */
    SPIScale24 fill_opacity;
    /** fill-rule: 0 nonzero, 1 evenodd */
    SPIEnum fill_rule;

    /** stroke */
    SPIPaint stroke;
    /** stroke-width */
    SPILength stroke_width;
    /** stroke-linecap */
    SPIEnum stroke_linecap;
    /** stroke-linejoin */
    SPIEnum stroke_linejoin;
    /** stroke-miterlimit */
    SPIFloat stroke_miterlimit;
    /** stroke-dash* */
    NRVpathDash stroke_dash;
    unsigned stroke_dasharray_set : 1;
    unsigned stroke_dasharray_inherit : 1;
    unsigned stroke_dashoffset_set : 1;
    /** stroke-opacity */
    SPIScale24 stroke_opacity;

    /** Marker list */
    SPIString marker[SP_MARKER_LOC_QTY];

    /// style belongs to a cloned object, must not href anything
    bool cloned;
    /// style has hreffed its color/fill/stroke paintservers, needs to release
    bool color_hreffed;
    bool fill_hreffed;
    bool stroke_hreffed;
    /// style is listening to changes in color/fill/stroke paintservers, needs to disconnect
    bool color_listening;
    bool fill_listening;
    bool stroke_listening;
};

SPStyle *sp_style_new();

SPStyle *sp_style_new_from_object(SPObject *object);

SPStyle *sp_style_ref(SPStyle *style);

SPStyle *sp_style_unref(SPStyle *style);

void sp_style_read_from_object(SPStyle *style, SPObject *object);

void sp_style_read_from_repr(SPStyle *style, Inkscape::XML::Node *repr);

void sp_style_merge_from_style_string(SPStyle *style, gchar const *p);

void sp_style_merge_from_parent(SPStyle *style, SPStyle const *parent);

void sp_style_merge_from_dying_parent(SPStyle *style, SPStyle const *parent);

gchar *sp_style_write_string(SPStyle const *style, guint flags = SP_STYLE_FLAG_IFSET);

gchar *sp_style_write_difference(SPStyle const *from, SPStyle const *to);

/* SPTextStyle */

enum SPCSSFontSize {
    SP_CSS_FONT_SIZE_XX_SMALL,
    SP_CSS_FONT_SIZE_X_SMALL,
    SP_CSS_FONT_SIZE_SMALL,
    SP_CSS_FONT_SIZE_MEDIUM,
    SP_CSS_FONT_SIZE_LARGE,
    SP_CSS_FONT_SIZE_X_LARGE,
    SP_CSS_FONT_SIZE_XX_LARGE,
    SP_CSS_FONT_SIZE_SMALLER,
    SP_CSS_FONT_SIZE_LARGER
};

enum SPCSSFontStyle {
    SP_CSS_FONT_STYLE_NORMAL,
    SP_CSS_FONT_STYLE_ITALIC,
    SP_CSS_FONT_STYLE_OBLIQUE
};

enum SPCSSFontVariant {
    SP_CSS_FONT_VARIANT_NORMAL,
    SP_CSS_FONT_VARIANT_SMALL_CAPS
};

enum SPCSSFontWeight {
    SP_CSS_FONT_WEIGHT_100,
    SP_CSS_FONT_WEIGHT_200,
    SP_CSS_FONT_WEIGHT_300,
    SP_CSS_FONT_WEIGHT_400,
    SP_CSS_FONT_WEIGHT_500,
    SP_CSS_FONT_WEIGHT_600,
    SP_CSS_FONT_WEIGHT_700,
    SP_CSS_FONT_WEIGHT_800,
    SP_CSS_FONT_WEIGHT_900,
    SP_CSS_FONT_WEIGHT_NORMAL,
    SP_CSS_FONT_WEIGHT_BOLD,
    SP_CSS_FONT_WEIGHT_LIGHTER,
    SP_CSS_FONT_WEIGHT_BOLDER
};

enum SPCSSFontStretch {
    SP_CSS_FONT_STRETCH_ULTRA_CONDENSED,
    SP_CSS_FONT_STRETCH_EXTRA_CONDENSED,
    SP_CSS_FONT_STRETCH_CONDENSED,
    SP_CSS_FONT_STRETCH_SEMI_CONDENSED,
    SP_CSS_FONT_STRETCH_NORMAL,
    SP_CSS_FONT_STRETCH_SEMI_EXPANDED,
    SP_CSS_FONT_STRETCH_EXPANDED,
    SP_CSS_FONT_STRETCH_EXTRA_EXPANDED,
    SP_CSS_FONT_STRETCH_ULTRA_EXPANDED,
    SP_CSS_FONT_STRETCH_NARROWER,
    SP_CSS_FONT_STRETCH_WIDER
};

enum SPCSSTextAlign {
    SP_CSS_TEXT_ALIGN_START,
    SP_CSS_TEXT_ALIGN_END,
    SP_CSS_TEXT_ALIGN_LEFT,
    SP_CSS_TEXT_ALIGN_RIGHT,
    SP_CSS_TEXT_ALIGN_CENTER,
    SP_CSS_TEXT_ALIGN_JUSTIFY
    // also <string> is allowed, but only within table calls
};

enum SPCSSTextTransform {
    SP_CSS_TEXT_TRANSFORM_CAPITALIZE,
    SP_CSS_TEXT_TRANSFORM_UPPERCASE,
    SP_CSS_TEXT_TRANSFORM_LOWERCASE,
    SP_CSS_TEXT_TRANSFORM_NONE
};

enum SPCSSDirection {
    SP_CSS_DIRECTION_LTR,
    SP_CSS_DIRECTION_RTL
};

enum SPCSSBlockProgression {
    SP_CSS_BLOCK_PROGRESSION_TB,
    SP_CSS_BLOCK_PROGRESSION_RL,
    SP_CSS_BLOCK_PROGRESSION_LR
};

enum SPCSSWritingMode {
    SP_CSS_WRITING_MODE_LR_TB,
    SP_CSS_WRITING_MODE_RL_TB,
    SP_CSS_WRITING_MODE_TB_RL,
    SP_CSS_WRITING_MODE_TB_LR
};

enum SPTextAnchor {
    SP_CSS_TEXT_ANCHOR_START,
    SP_CSS_TEXT_ANCHOR_MIDDLE,
    SP_CSS_TEXT_ANCHOR_END
};

enum SPVisibility {
    SP_CSS_VISIBILITY_HIDDEN,
    SP_CSS_VISIBILITY_COLLAPSE,
    SP_CSS_VISIBILITY_VISIBLE
};

enum SPOverflow {
    SP_CSS_OVERFLOW_VISIBLE,
    SP_CSS_OVERFLOW_HIDDEN,
    SP_CSS_OVERFLOW_SCROLL,
    SP_CSS_OVERFLOW_AUTO
};

/// \todo more display types
enum SPCSSDisplay {
    SP_CSS_DISPLAY_NONE,
    SP_CSS_DISPLAY_INLINE,
    SP_CSS_DISPLAY_BLOCK,
    SP_CSS_DISPLAY_LIST_ITEM,
    SP_CSS_DISPLAY_RUN_IN,
    SP_CSS_DISPLAY_COMPACT,
    SP_CSS_DISPLAY_MARKER,
    SP_CSS_DISPLAY_TABLE,
    SP_CSS_DISPLAY_INLINE_TABLE,
    SP_CSS_DISPLAY_TABLE_ROW_GROUP,
    SP_CSS_DISPLAY_TABLE_HEADER_GROUP,
    SP_CSS_DISPLAY_TABLE_FOOTER_GROUP,
    SP_CSS_DISPLAY_TABLE_ROW,
    SP_CSS_DISPLAY_TABLE_COLUMN_GROUP,
    SP_CSS_DISPLAY_TABLE_COLUMN,
    SP_CSS_DISPLAY_TABLE_CELL,
    SP_CSS_DISPLAY_TABLE_CAPTION
};

/// An SPTextStyle has a refcount, a font family, and a font name.
struct SPTextStyle {
    int refcount;

    /* CSS font properties */
    SPIString font_family;

    /** \todo fixme: The 'font' property is ugly, and not working (lauris) */
    SPIString font;
};

SPCSSAttr *sp_css_attr_from_style (SPStyle const *const style, guint flags);
SPCSSAttr *sp_css_attr_from_object(SPObject *object, guint flags = SP_STYLE_FLAG_IFSET);
SPCSSAttr *sp_css_attr_unset_text(SPCSSAttr *css);
SPCSSAttr *sp_css_attr_unset_uris(SPCSSAttr *css);
SPCSSAttr *sp_css_attr_scale(SPCSSAttr *css, double ex);

void sp_style_unset_property_attrs(SPObject *o);

#endif


/*
  Local Variables:
  mode:c++
  c-file-style:"stroustrup"
  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
  indent-tabs-mode:nil
  fill-column:99
  End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :