netsurf/desktop/save_pdf/font_haru.c

377 lines
9.0 KiB
C

/*
* Copyright 2008 Adam Blokus <adamblokus@gmail.com>
* Copyright 2009 John Tytgat <joty@netsurf-browser.org>
*
* This file is part of NetSurf, http://www.netsurf-browser.org/
*
* NetSurf is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* NetSurf is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/** \file
* Font handling in Haru pdf documents (implementation).
*
* The functions were written to implement the same interface as the Pango ones
* so that the usage of the latter wouldn't have to be modified.
*/
#include "utils/config.h"
#ifdef WITH_PDF_EXPORT
/*#define FONT_HARU_DEBUG */
#include <assert.h>
#include <float.h>
#include <math.h>
#include <string.h>
#include <hpdf.h>
#include "css/css.h"
#include "css/utils.h"
#include "desktop/options.h"
#include "desktop/save_pdf/font_haru.h"
#include "render/font.h"
#include "utils/log.h"
static bool haru_nsfont_init(HPDF_Doc *pdf, HPDF_Page *page,
const char *string, char **string_nt, int length);
static bool haru_nsfont_width(const plot_font_style_t *fstyle,
const char *string, size_t length,
int *width);
static bool haru_nsfont_position_in_string(const plot_font_style_t *fstyle,
const char *string, size_t length,
int x, size_t *char_offset, int *actual_x);
static bool haru_nsfont_split(const plot_font_style_t *fstyle,
const char *string, size_t length,
int x, size_t *char_offset, int *actual_x);
static float pdf_text_scale = DEFAULT_EXPORT_SCALE;
const struct font_functions haru_nsfont = {
haru_nsfont_width,
haru_nsfont_position_in_string,
haru_nsfont_split
};
/**
* Haru error handler
* for debugging purposes - it immediately exits the program on the first error,
* as it would otherwise flood the user with all resulting complications,
* covering the most important error source.
*/
static void error_handler(HPDF_STATUS error_no, HPDF_STATUS detail_no,
void *user_data)
{
LOG(("ERROR: in font_haru \n\terror_no=%x\n\tdetail_no=%d\n",
(HPDF_UINT)error_no, (HPDF_UINT)detail_no));
#ifdef FONT_HARU_DEBUG
exit(1);
#endif
}
static bool haru_nsfont_init(HPDF_Doc *pdf, HPDF_Page *page,
const char *string, char **string_nt, int length)
{
*pdf = HPDF_New(error_handler, NULL);
if (*pdf == NULL)
return false;
*page = HPDF_AddPage(*pdf);
if (*page == NULL) {
HPDF_Free(*pdf);
return false;
}
*string_nt = malloc((length + 1) * sizeof(char));
if (*string_nt == NULL) {
HPDF_Free(*pdf);
return false;
}
memcpy(*string_nt, string, length);
(*string_nt)[length] = '\0';
return true;
}
/**
* Measure the width of a string.
*
* \param fstyle style for this text
* \param string string to measure (no UTF-8 currently)
* \param length length of string
* \param width updated to width of string[0..length]
* \return true on success, false on error and error reported
*/
bool haru_nsfont_width(const plot_font_style_t *fstyle,
const char *string, size_t length,
int *width)
{
HPDF_Doc pdf;
HPDF_Page page;
char *string_nt;
HPDF_REAL width_real;
*width = 0;
if (length == 0)
return true;
if (!haru_nsfont_init(&pdf, &page, string, &string_nt, length))
return false;
if (!haru_nsfont_apply_style(fstyle, pdf, page, NULL, NULL)) {
free(string_nt);
HPDF_Free(pdf);
return false;
}
width_real = HPDF_Page_TextWidth(page, string_nt);
*width = width_real;
#ifdef FONT_HARU_DEBUG
LOG(("Measuring string: %s ; Calculated width: %f %i",string_nt, width_real, *width));
#endif
free(string_nt);
HPDF_Free(pdf);
return true;
}
/**
* Find the position in a string where an x coordinate falls.
*
* \param fstyle style for this text
* \param string string to measure (no UTF-8 currently)
* \param length length of string
* \param x x coordinate to search for
* \param char_offset updated to offset in string of actual_x, [0..length]
* \param actual_x updated to x coordinate of character closest to x
* \return true on success, false on error and error reported
*/
bool haru_nsfont_position_in_string(const plot_font_style_t *fstyle,
const char *string, size_t length,
int x, size_t *char_offset, int *actual_x)
{
HPDF_Doc pdf;
HPDF_Page page;
char *string_nt;
HPDF_UINT offset;
HPDF_REAL real_width;
if (!haru_nsfont_init(&pdf, &page, string, &string_nt, length))
return false;
if (HPDF_Page_SetWidth(page, x) != HPDF_OK
|| !haru_nsfont_apply_style(fstyle, pdf, page, NULL, NULL)) {
free(string_nt);
HPDF_Free(pdf);
return false;
}
offset = HPDF_Page_MeasureText(page, string_nt, x,
HPDF_FALSE, &real_width);
if (real_width < x)
*char_offset = offset;
else {
assert(fabs(real_width - x) < FLT_EPSILON);
assert(offset > 0);
*char_offset = offset - 1;
}
/*TODO: this is only the right edge of the character*/
*actual_x = real_width;
#ifdef FONT_HARU_DEBUG
LOG(("Position in string: %s at x: %i; Calculated position: %i",
string_nt, x, *char_offset));
#endif
free(string_nt);
HPDF_Free(pdf);
return true;
}
/**
* Find where to split a string to make it fit a width.
*
* \param fstyle style for this text
* \param string string to measure (no UTF-8 currently)
* \param length length of string
* \param x width available
* \param char_offset updated to offset in string of actual_x, [0..length]
* \param actual_x updated to x coordinate of character closest to x
* \return true on success, false on error and error reported
*/
bool haru_nsfont_split(const plot_font_style_t *fstyle,
const char *string, size_t length,
int x, size_t *char_offset, int *actual_x)
{
HPDF_Doc pdf;
HPDF_Page page;
char *string_nt;
HPDF_REAL real_width;
HPDF_UINT offset;
if (!haru_nsfont_init(&pdf, &page, string, &string_nt, length))
return false;
if (HPDF_Page_SetWidth(page, x) != HPDF_OK
|| !haru_nsfont_apply_style(fstyle, pdf, page, NULL, NULL)) {
free(string_nt);
HPDF_Free(pdf);
return false;
}
offset = HPDF_Page_MeasureText(page, string_nt, x,
HPDF_TRUE, &real_width);
#ifdef FONT_HARU_DEBUG
LOG(("Splitting string: %s for width: %i ; Calculated position: %i Calculated real_width: %f",
string_nt, x, *char_offset, real_width));
#endif
*char_offset = offset - 1;
/*TODO: this is only the right edge of the character*/
*actual_x = real_width;
free(string_nt);
HPDF_Free(pdf);
return true;
}
/**
* Apply font style to a Haru HPDF_Page
*
* \param fstyle plot style for this page
* \param doc document owning the page
* \param page the page to apply the style to
* \param font if this is non NULL it is updated to the font based
* on given style
* \param font_size if this is non NULL it is updated to the font size
* based on given style
* \return true on success, false on error and error reported
*
* When both font and font_size are NULL, the HPDF_Page is updated for given
* style, otherwise it is left to the called to do this.
*/
bool haru_nsfont_apply_style(const plot_font_style_t *fstyle,
HPDF_Doc doc, HPDF_Page page,
HPDF_Font *font, HPDF_REAL *font_size)
{
HPDF_Font pdf_font;
HPDF_REAL size;
char font_name[50];
bool roman = false;
bool bold = false;
bool styled = false;
/*TODO: style handling, we are mapping the
styles on the basic 14 fonts only
*/
switch (fstyle->family) {
case PLOT_FONT_FAMILY_SERIF:
strcpy(font_name, "Times");
roman = true;
break;
case PLOT_FONT_FAMILY_MONOSPACE:
strcpy(font_name, "Courier");
break;
case PLOT_FONT_FAMILY_SANS_SERIF:
strcpy(font_name, "Helvetica");
break;
case PLOT_FONT_FAMILY_CURSIVE:
case PLOT_FONT_FAMILY_FANTASY:
default:
strcpy(font_name, "Times");
roman=true;
break;
}
if (fstyle->weight == 700) {
strcat(font_name, "-Bold");
bold = true;
}
if ((fstyle->flags & FONTF_ITALIC) || (fstyle->flags & FONTF_OBLIQUE)) {
if (!bold)
strcat(font_name,"-");
if (roman)
strcat(font_name,"Italic");
else
strcat(font_name,"Oblique");
styled = true;
}
if (roman && !styled && !bold)
strcat(font_name, "-Roman");
#ifdef FONT_HARU_DEBUG
LOG(("Setting font: %s", font_name));
#endif
size = fstyle->size;
if (font != NULL)
size *= pdf_text_scale;
if (size <= 0)
return true;
size /= FONT_SIZE_SCALE;
if (size > HPDF_MAX_FONTSIZE)
size = HPDF_MAX_FONTSIZE;
if (font_size)
*font_size = size;
pdf_font = HPDF_GetFont(doc, font_name, "StandardEncoding");
if (pdf_font == NULL)
return false;
if (font != NULL)
*font = pdf_font;
if (font == NULL || font_size == NULL)
HPDF_Page_SetFontAndSize(page, pdf_font, size);
return true;
}
/**
* Sync the text scale with the scale for the whole content
*/
void haru_nsfont_set_scale(float s)
{
pdf_text_scale = s;
}
#endif /* WITH_PDF_EXPORT */