Layout-TNG-Input.cpp revision 1b5578543615e948325cbc197bfa14a5450eed2f
/*
* Inkscape::Text::Layout - text layout engine input functions
*
* Authors:
* Richard Hughes <cyreve@users.sf.net>
*
* Copyright (C) 2005 Richard Hughes
*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifndef PANGO_ENABLE_ENGINE
#define PANGO_ENABLE_ENGINE
#endif
#include <gtk/gtk.h>
#include "Layout-TNG.h"
#include "style.h"
#include "svg/svg-length.h"
#include "sp-object.h"
#include "sp-string.h"
#include "FontFactory.h"
namespace Inkscape {
namespace Text {
void Layout::_clearInputObjects()
{
for(std::vector<InputStreamItem*>::iterator it = _input_stream.begin() ; it != _input_stream.end() ; ++it) {
delete *it;
}
_input_stream.clear();
_input_wrap_shapes.clear();
}
// this function does nothing more than store all its parameters for future reference
void Layout::appendText(Glib::ustring const &text, SPStyle *style, void *source_cookie, OptionalTextTagAttrs const *optional_attributes, unsigned optional_attributes_offset, Glib::ustring::const_iterator text_begin, Glib::ustring::const_iterator text_end)
{
if (style == NULL) return;
InputStreamTextSource *new_source = new InputStreamTextSource;
new_source->source_cookie = source_cookie;
new_source->text = &text;
new_source->text_begin = text_begin;
new_source->text_end = text_end;
new_source->style = style;
sp_style_ref(style);
new_source->text_length = 0;
for ( ; text_begin != text_end && text_begin != text.end() ; ++text_begin)
new_source->text_length++; // save this because calculating the length of a UTF-8 string is expensive
if (optional_attributes) {
// we need to fill in x and y even if the text is empty so that empty paragraphs can be positioned correctly
_copyInputVector(optional_attributes->x, optional_attributes_offset, &new_source->x, std::max(1, new_source->text_length));
_copyInputVector(optional_attributes->y, optional_attributes_offset, &new_source->y, std::max(1, new_source->text_length));
_copyInputVector(optional_attributes->dx, optional_attributes_offset, &new_source->dx, new_source->text_length);
_copyInputVector(optional_attributes->dy, optional_attributes_offset, &new_source->dy, new_source->text_length);
_copyInputVector(optional_attributes->rotate, optional_attributes_offset, &new_source->rotate, new_source->text_length);
if (!optional_attributes->rotate.empty() && optional_attributes_offset >= optional_attributes->rotate.size()) {
SVGLength last_rotate;
last_rotate = 0.f;
for (std::vector<SVGLength>::const_iterator it = optional_attributes->rotate.begin() ; it != optional_attributes->rotate.end() ; ++it)
if (it->_set)
last_rotate = *it;
new_source->rotate.resize(1, last_rotate);
}
new_source->textLength._set = optional_attributes->textLength._set;
new_source->textLength.value = optional_attributes->textLength.value;
new_source->textLength.computed = optional_attributes->textLength.computed;
new_source->textLength.unit = optional_attributes->textLength.unit;
new_source->lengthAdjust = optional_attributes->lengthAdjust;
}
_input_stream.push_back(new_source);
}
void Layout::_copyInputVector(std::vector<SVGLength> const &input_vector, unsigned input_offset, std::vector<SVGLength> *output_vector, size_t max_length)
{
output_vector->clear();
if (input_offset >= input_vector.size()) return;
output_vector->reserve(std::min(max_length, input_vector.size() - input_offset));
while (input_offset < input_vector.size() && max_length != 0) {
if (!input_vector[input_offset]._set)
break;
output_vector->push_back(input_vector[input_offset]);
input_offset++;
max_length--;
}
}
// just save what we've been given, really
void Layout::appendControlCode(TextControlCode code, void *source_cookie, double width, double ascent, double descent)
{
InputStreamControlCode *new_code = new InputStreamControlCode;
new_code->source_cookie = source_cookie;
new_code->code = code;
new_code->width = width;
new_code->ascent = ascent;
new_code->descent = descent;
_input_stream.push_back(new_code);
}
// more saving of the parameters
void Layout::appendWrapShape(Shape const *shape, DisplayAlign display_align)
{
_input_wrap_shapes.push_back(InputWrapShape());
_input_wrap_shapes.back().shape = shape;
_input_wrap_shapes.back().display_align = display_align;
}
int Layout::_enum_converter(int input, EnumConversionItem const *conversion_table, unsigned conversion_table_size)
{
for (unsigned i = 0 ; i < conversion_table_size ; i++)
if (conversion_table[i].input == input)
return conversion_table[i].output;
return conversion_table[0].output;
}
// ***** the style format interface
// this doesn't include all accesses to SPStyle, only the ones that are non-trivial
static const float medium_font_size = 12.0; // more of a default if all else fails than anything else
float Layout::InputStreamTextSource::styleComputeFontSize() const
{
return style->font_size.computed;
// in case the computed value's not good enough, here's some manual code held in reserve:
SPStyle const *this_style = style;
float inherit_multiplier = 1.0;
for ( ; ; ) {
if (this_style->font_size.set && !this_style->font_size.inherit) {
switch (this_style->font_size.type) {
case SP_FONT_SIZE_LITERAL: {
switch(this_style->font_size.literal) { // these multipliers are straight out of the CSS spec
case SP_CSS_FONT_SIZE_XX_SMALL: return medium_font_size * inherit_multiplier * (3.0/5.0);
case SP_CSS_FONT_SIZE_X_SMALL: return medium_font_size * inherit_multiplier * (3.0/4.0);
case SP_CSS_FONT_SIZE_SMALL: return medium_font_size * inherit_multiplier * (8.0/9.0);
default:
case SP_CSS_FONT_SIZE_MEDIUM: return medium_font_size * inherit_multiplier;
case SP_CSS_FONT_SIZE_LARGE: return medium_font_size * inherit_multiplier * (6.0/5.0);
case SP_CSS_FONT_SIZE_X_LARGE: return medium_font_size * inherit_multiplier * (3.0/2.0);
case SP_CSS_FONT_SIZE_XX_LARGE: return medium_font_size * inherit_multiplier * 2.0;
case SP_CSS_FONT_SIZE_SMALLER: inherit_multiplier *= 0.84; break; //not exactly according to spec
case SP_CSS_FONT_SIZE_LARGER: inherit_multiplier *= 1.26; break; //not exactly according to spec
}
break;
}
case SP_FONT_SIZE_PERCENTAGE: { // 'em' units should be in here, but aren't. Fix in style.cpp.
inherit_multiplier *= this_style->font_size.value;
break;
}
case SP_FONT_SIZE_LENGTH: {
return this_style->font_size.value * inherit_multiplier;
}
}
}
if (this_style->object == NULL || this_style->object->parent == NULL) break;
this_style = this_style->object->parent->style;
if (this_style == NULL) break;
}
return medium_font_size * inherit_multiplier;
}
static const Layout::EnumConversionItem enum_convert_spstyle_block_progression_to_direction[] = {
{SP_CSS_BLOCK_PROGRESSION_TB, Layout::TOP_TO_BOTTOM},
{SP_CSS_BLOCK_PROGRESSION_LR, Layout::LEFT_TO_RIGHT},
{SP_CSS_BLOCK_PROGRESSION_RL, Layout::RIGHT_TO_LEFT}};
static const Layout::EnumConversionItem enum_convert_spstyle_writing_mode_to_direction[] = {
{SP_CSS_WRITING_MODE_LR_TB, Layout::TOP_TO_BOTTOM},
{SP_CSS_WRITING_MODE_RL_TB, Layout::TOP_TO_BOTTOM},
{SP_CSS_WRITING_MODE_TB_RL, Layout::RIGHT_TO_LEFT},
{SP_CSS_WRITING_MODE_TB_LR, Layout::LEFT_TO_RIGHT}};
Layout::Direction Layout::InputStreamTextSource::styleGetBlockProgression() const
{
// this function shouldn't be necessary, but since style.cpp doesn't support
// shorthand properties yet, it is.
SPStyle const *this_style = style;
for ( ; ; ) {
if (this_style->block_progression.set)
return (Layout::Direction)_enum_converter(this_style->block_progression.computed, enum_convert_spstyle_block_progression_to_direction, sizeof(enum_convert_spstyle_block_progression_to_direction)/sizeof(enum_convert_spstyle_block_progression_to_direction[0]));
if (this_style->writing_mode.set)
return (Layout::Direction)_enum_converter(this_style->writing_mode.computed, enum_convert_spstyle_writing_mode_to_direction, sizeof(enum_convert_spstyle_writing_mode_to_direction)/sizeof(enum_convert_spstyle_writing_mode_to_direction[0]));
if (this_style->object == NULL || this_style->object->parent == NULL) break;
this_style = this_style->object->parent->style;
if (this_style == NULL) break;
}
return TOP_TO_BOTTOM;
}
static Layout::Alignment text_anchor_to_alignment(unsigned anchor, Layout::Direction /*para_direction*/)
{
switch (anchor) {
default:
case SP_CSS_TEXT_ANCHOR_START: return Layout::LEFT;
case SP_CSS_TEXT_ANCHOR_MIDDLE: return Layout::CENTER;
case SP_CSS_TEXT_ANCHOR_END: return Layout::RIGHT;
}
}
Layout::Alignment Layout::InputStreamTextSource::styleGetAlignment(Layout::Direction para_direction, bool try_text_align) const
{
if (!try_text_align)
return text_anchor_to_alignment(style->text_anchor.computed, para_direction);
// there's no way to tell the difference between text-anchor set higher up the cascade to the default and
// text-anchor never set anywhere in the cascade, so in order to detect which of text-anchor or text-align
// to use we'll have to run up the style tree ourselves.
SPStyle const *this_style = style;
for ( ; ; ) {
// If both text-align and text-anchor are set at the same level, text-align takes
// precedence because it is the most expressive.
if (this_style->text_align.set) {
switch (style->text_align.computed) {
default:
case SP_CSS_TEXT_ALIGN_START: return para_direction == LEFT_TO_RIGHT ? LEFT : RIGHT;
case SP_CSS_TEXT_ALIGN_END: return para_direction == LEFT_TO_RIGHT ? RIGHT : LEFT;
case SP_CSS_TEXT_ALIGN_LEFT: return LEFT;
case SP_CSS_TEXT_ALIGN_RIGHT: return RIGHT;
case SP_CSS_TEXT_ALIGN_CENTER: return CENTER;
case SP_CSS_TEXT_ALIGN_JUSTIFY: return FULL;
}
}
if (this_style->text_anchor.set)
return text_anchor_to_alignment(this_style->text_anchor.computed, para_direction);
if (this_style->object == NULL || this_style->object->parent == NULL) break;
this_style = this_style->object->parent->style;
if (this_style == NULL) break;
}
return para_direction == LEFT_TO_RIGHT ? LEFT : RIGHT;
}
static const Layout::EnumConversionItem enum_convert_spstyle_style_to_pango_style[] = {
{SP_CSS_FONT_STYLE_NORMAL, PANGO_STYLE_NORMAL},
{SP_CSS_FONT_STYLE_ITALIC, PANGO_STYLE_ITALIC},
{SP_CSS_FONT_STYLE_OBLIQUE, PANGO_STYLE_OBLIQUE}};
static const Layout::EnumConversionItem enum_convert_spstyle_weight_to_pango_weight[] = {
// NB: The Pango web page calls 500 "the normal font" but both CSS2 and the Pango
// enumeration define 400 as normal.
{SP_CSS_FONT_WEIGHT_NORMAL, PANGO_WEIGHT_NORMAL},
{SP_CSS_FONT_WEIGHT_BOLD,PANGO_WEIGHT_BOLD},
{SP_CSS_FONT_WEIGHT_100, PANGO_WEIGHT_THIN},
{SP_CSS_FONT_WEIGHT_200, PANGO_WEIGHT_ULTRALIGHT},
{SP_CSS_FONT_WEIGHT_300, PANGO_WEIGHT_LIGHT},
{SP_CSS_FONT_WEIGHT_400, PANGO_WEIGHT_NORMAL},
{SP_CSS_FONT_WEIGHT_500, PANGO_WEIGHT_MEDIUM},
{SP_CSS_FONT_WEIGHT_600, PANGO_WEIGHT_SEMIBOLD},
{SP_CSS_FONT_WEIGHT_700, PANGO_WEIGHT_BOLD},
{SP_CSS_FONT_WEIGHT_800, PANGO_WEIGHT_ULTRABOLD},
{SP_CSS_FONT_WEIGHT_900, PANGO_WEIGHT_HEAVY}};
static const Layout::EnumConversionItem enum_convert_spstyle_stretch_to_pango_stretch[] = {
{SP_CSS_FONT_STRETCH_NORMAL, PANGO_STRETCH_NORMAL},
{SP_CSS_FONT_STRETCH_ULTRA_CONDENSED, PANGO_STRETCH_ULTRA_CONDENSED},
{SP_CSS_FONT_STRETCH_EXTRA_CONDENSED, PANGO_STRETCH_EXTRA_CONDENSED},
{SP_CSS_FONT_STRETCH_CONDENSED, PANGO_STRETCH_CONDENSED},
{SP_CSS_FONT_STRETCH_SEMI_CONDENSED, PANGO_STRETCH_SEMI_CONDENSED},
{SP_CSS_FONT_STRETCH_SEMI_EXPANDED, PANGO_STRETCH_SEMI_EXPANDED},
{SP_CSS_FONT_STRETCH_EXPANDED, PANGO_STRETCH_EXPANDED},
{SP_CSS_FONT_STRETCH_EXTRA_EXPANDED, PANGO_STRETCH_EXTRA_EXPANDED},
{SP_CSS_FONT_STRETCH_ULTRA_EXPANDED, PANGO_STRETCH_ULTRA_EXPANDED}};
static const Layout::EnumConversionItem enum_convert_spstyle_variant_to_pango_variant[] = {
{SP_CSS_FONT_VARIANT_NORMAL, PANGO_VARIANT_NORMAL},
{SP_CSS_FONT_VARIANT_SMALL_CAPS, PANGO_VARIANT_SMALL_CAPS}};
font_instance *Layout::InputStreamTextSource::styleGetFontInstance() const
{
PangoFontDescription *descr = styleGetFontDescription();
if (descr == NULL) return NULL;
font_instance *res = (font_factory::Default())->Face(descr);
pango_font_description_free(descr);
return res;
}
PangoFontDescription *Layout::InputStreamTextSource::styleGetFontDescription() const
{
PangoFontDescription *descr = pango_font_description_new();
// Pango can't cope with spaces before or after the commas - let's remove them.
// this code is not exactly unicode-safe, but it's similar to what's done in
// pango, so it's not the limiting factor
Glib::ustring family;
if (style->font_family.value == NULL) {
family = "sans-serif";
} else {
gchar **families = g_strsplit(style->font_family.value, ",", -1);
if (families) {
for (gchar **f = families ; *f ; ++f) {
g_strstrip(*f);
if (!family.empty()) family += ',';
family += *f;
}
}
g_strfreev(families);
}
pango_font_description_set_family(descr,family.c_str());
pango_font_description_set_weight(descr,(PangoWeight)_enum_converter(style->font_weight.computed, enum_convert_spstyle_weight_to_pango_weight, sizeof(enum_convert_spstyle_weight_to_pango_weight)/sizeof(enum_convert_spstyle_weight_to_pango_weight[0])));
pango_font_description_set_style(descr,(PangoStyle)_enum_converter(style->font_style.computed, enum_convert_spstyle_style_to_pango_style, sizeof(enum_convert_spstyle_style_to_pango_style)/sizeof(enum_convert_spstyle_style_to_pango_style[0])));
pango_font_description_set_variant(descr,(PangoVariant)_enum_converter(style->font_variant.computed, enum_convert_spstyle_variant_to_pango_variant, sizeof(enum_convert_spstyle_variant_to_pango_variant)/sizeof(enum_convert_spstyle_variant_to_pango_variant[0])));
#ifdef USE_PANGO_WIN32
// damn Pango fudges the size, so we need to unfudge. See source of pango_win32_font_map_init()
pango_font_description_set_size(descr, (int) ((font_factory::Default())->fontSize*PANGO_SCALE*72/GetDeviceCaps(pango_win32_get_dc(),LOGPIXELSY))); // mandatory huge size (hinting workaround)
// we don't set stretch on Win32, because pango-win32 has no concept of it
// (Windows doesn't really provide any useful field it could use).
// If we did set stretch, then any text with a font-stretch attribute would
// end up falling back to Arial.
#else
pango_font_description_set_size(descr, (int) ((font_factory::Default())->fontSize*PANGO_SCALE)); // mandatory huge size (hinting workaround)
pango_font_description_set_stretch(descr,(PangoStretch)_enum_converter(style->font_stretch.computed, enum_convert_spstyle_stretch_to_pango_stretch, sizeof(enum_convert_spstyle_stretch_to_pango_stretch)/sizeof(enum_convert_spstyle_stretch_to_pango_stretch[0])));
#endif
return descr;
}
Layout::InputStreamTextSource::~InputStreamTextSource()
{
sp_style_unref(style);
}
}//namespace Text
}//namespace Inkscape