netsurf/amiga/font.c

/*
 * Copyright 2005 James Bursa <bursa@users.sourceforge.net>
 *           2008 Chris Young <chris@unsatisfactorysoftware.co.uk>
 *
 * 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/>.
 */

#include <assert.h>
#include "css/css.h"
#include "render/font.h"
#include "amiga/gui.h"
#include <proto/graphics.h>
#include <proto/diskfont.h>
#include <graphics/rpattr.h>
#include "amiga/font.h"
#include "desktop/options.h"
#include "amiga/utf8.h"
#include "utils/utf8.h"
#include <diskfont/diskfonttag.h>
#include <diskfont/oterrors.h>
#include <proto/Picasso96API.h>
#include <proto/exec.h>

static bool nsfont_width(const struct css_style *style,
	  const char *string, size_t length,
    int *width);
       
static bool nsfont_position_in_string(const struct css_style *style,
	       const char *string, size_t length,
	  int x, size_t *char_offset, int *actual_x);
       
static bool nsfont_split(const struct css_style *style,
	  const char *string, size_t length,
    int x, size_t *char_offset, int *actual_x);

const struct font_functions nsfont = {
	nsfont_width,
	nsfont_position_in_string,
	nsfont_split
};

bool nsfont_width(const struct css_style *style,
		const char *string, size_t length,
		int *width)
{
	struct TextFont *tfont = ami_open_font(style);
	*width = TextLength(currp,string,length); //buffer,strlen(buffer));
	ami_close_font(tfont);
	return true;
}

/**
 * Find the position in a string where an x coordinate falls.
 *
 * \param  style        css_style for this text, with style->font_size.size ==
 *                      CSS_FONT_SIZE_LENGTH
 * \param  string       UTF-8 string to measure
 * \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 nsfont_position_in_string(const struct css_style *style,
		const char *string, size_t length,
		int x, size_t *char_offset, int *actual_x)
{
	struct TextExtent extent;
	struct TextFont *tfont = ami_open_font(style);

	*char_offset = TextFit(currp,string,length,
						&extent,NULL,1,x,32767);

	*actual_x = extent.te_Extent.MaxX;

	ami_close_font(tfont);
	return true;
}


/**
 * Find where to split a string to make it fit a width.
 *
 * \param  style        css_style for this text, with style->font_size.size ==
 *                      CSS_FONT_SIZE_LENGTH
 * \param  string       UTF-8 string to measure
 * \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
 *
 * On exit, [char_offset == 0 ||
 *           string[char_offset] == ' ' ||
 *           char_offset == length]
 */

bool nsfont_split(const struct css_style *style,
		const char *string, size_t length,
		int x, size_t *char_offset, int *actual_x)
{
	struct TextExtent extent;
	ULONG co;
	char *charp;
	struct TextFont *tfont = ami_open_font(style);

	co = TextFit(currp,string,length,
				&extent,NULL,1,x,32767);

	charp = string+co;
	while(((*charp != ' ')) && (charp > string))
	{
		charp--;
		co--;
	}

	*char_offset = co;
	if(string && co)
	{
		*actual_x = TextLength(currp,string,co);
	}
	else
	{
		*actual_x = 0;
	}

	ami_close_font(tfont);
	return true;
}

struct TextFont *ami_open_font(struct css_style *style)
{
	struct TextFont *tfont;
	struct TTextAttr tattr;
	struct TagItem tattrtags[2];
	char fontname[256];

	switch(style->font_family)
	{
		case CSS_FONT_FAMILY_SANS_SERIF:
			strcpy(fontname,option_font_sans);
		break;

		case CSS_FONT_FAMILY_SERIF:
			strcpy(fontname,option_font_serif);
		break;

		case CSS_FONT_FAMILY_MONOSPACE:
			strcpy(fontname,option_font_mono);
		break;

		case CSS_FONT_FAMILY_CURSIVE:
			strcpy(fontname,option_font_cursive);
		break;

		case CSS_FONT_FAMILY_FANTASY:
			strcpy(fontname,option_font_fantasy);
		break;

		default:
			strcpy(fontname,option_font_sans);
		break;
	}

	switch(style->font_style)
	{
		case CSS_FONT_STYLE_ITALIC:
		case CSS_FONT_STYLE_OBLIQUE:
			tattr.tta_Style = FSF_ITALIC;
		break;

		default:
			tattr.tta_Style = FS_NORMAL;
		break;
	}

	switch(style->font_weight)
	{
		case CSS_FONT_WEIGHT_BOLD:
		case CSS_FONT_WEIGHT_BOLDER:
			tattr.tta_Style |= FSF_BOLD;
		break;
	}

/* not supported
	switch(style->font_variant)
	{
		default:
			//printf("font variant: %ld\n",style->font_variant);
		break;
	}
*/

	tattr.tta_YSize = css_len2px(&style->font_size.value.length, style);

	if(tattr.tta_YSize < option_font_min_size)
		tattr.tta_YSize = option_font_min_size;

	tattr.tta_Flags = 0;

/* Uncommenting this changes the font's charset.
   106 is UTF-8 but OS4 doesn't support it so this only results in a crash! 

	tattrtags[0].ti_Tag = TA_CharSet;
	tattrtags[0].ti_Data = 106;
	tattrtags[1].ti_Tag = TAG_DONE;

	tattr.tta_Flags = FSB_TAGGED;  
	tattr.tta_Tags = &tattrtags;
*/

	strcat(fontname,".font");
	tattr.tta_Name = fontname;

	tfont = OpenDiskFont((struct TextAttr *)&tattr);

	if(tfont)
	{
		SetRPAttrs(currp,
				RPTAG_Font,tfont,
				TAG_DONE);
	}

	return tfont;
}

struct OutlineFont *ami_open_outline_font(struct css_style *style)
{
	struct OutlineFont *ofont;
	char *fontname;
	WORD ysize;

	switch(style->font_family)
	{
		case CSS_FONT_FAMILY_SANS_SERIF:
			fontname = option_font_sans;
		break;

		case CSS_FONT_FAMILY_SERIF:
			fontname = option_font_serif;
		break;

		case CSS_FONT_FAMILY_MONOSPACE:
			fontname = option_font_mono;
		break;

		case CSS_FONT_FAMILY_CURSIVE:
			fontname = option_font_cursive;
		break;

		case CSS_FONT_FAMILY_FANTASY:
			fontname = option_font_fantasy;
		break;

		default:
			fontname = option_font_sans;
		break;
	}

	if(!(ofont = OpenOutlineFont(fontname,NULL,OFF_OPEN))) return NULL;

/* see diskfont implementation for currently unimplemented bold/italic stuff */

	ysize = css_len2px(&style->font_size.value.length, style);

	if(ysize < option_font_min_size)
		ysize = option_font_min_size;

	if(ESetInfo(&ofont->olf_EEngine,
				OT_DeviceDPI,(72<<16) | 72,
				OT_PointHeight,(ysize<<16),
				TAG_END) == OTERR_Success)
	{

	}
	else
	{
		CloseOutlineFont(ofont,NULL);
		return NULL;
	}

	return ofont;
}

void ami_close_outline_font(struct OutlineFont *ofont)
{
	if(ofont) CloseOutlineFont(ofont,NULL);
}

void ami_close_font(struct TextFont *tfont)
{
	SetRPAttrs(currp,
			RPTAG_Font,origrpfont,
			TAG_DONE);

	if(tfont) CloseFont(tfont);
}

void ami_unicode_text(struct RastPort *rp,char *string,ULONG length,struct css_style *style,ULONG x, ULONG y, ULONG c)
{
	WORD *utf16 = NULL;
	struct OutlineFont *ofont;
	struct GlyphMap *glyph;
	ULONG i,gx,gy;
	UBYTE *glyphbm;
	UWORD posn;

	if(!string || string[0]=='\0') return;
	if(!length) return;

	if(utf8_to_enc(string,"UTF-16",length,&utf16) != UTF8_CONVERT_OK) return;

	if(!(ofont = ami_open_outline_font(style))) return;

	for(i=0;i<length;i++)
	{
		if(ESetInfo(&ofont->olf_EEngine,
			OT_GlyphCode,utf16[i],
			TAG_END) == OTERR_Success)
		{
			if(EObtainInfo(&ofont->olf_EEngine,
				OT_GlyphMap8Bit,&glyph,
				TAG_END) == 0)
			{
				glyphbm = glyph->glm_BitMap;
				if(!glyphbm) continue;

				posn = 0; //(glyph->glm_BlackTop * glyph->glm_BMRows) + glyph->glm_BlackLeft;

				x+= glyph->glm_BlackLeft;

				for(gy=0;gy<glyph->glm_BlackHeight;gy++)
				{
					for(gx=0;gx<glyph->glm_BlackWidth;gx++)
					{
/* This works... except it doesn't.  Current public SDK doesn't have BltBitMapTags(),
which is needed along with BLITA_UseSrcAlpha, TRUE to respect the alpha channel.
We may even need to draw this text into a new bitmap and blit that onto our off-screen
rendering bitmap. */
						p96WritePixel(rp,x+gx,(y-glyph->glm_BlackHeight)+gy,
							p96EncodeColor(RGBFB_A8B8G8R8,(glyphbm[posn+gx] << 24) | c));
					}

					posn+=glyph->glm_BMModulo;
				}
				x+= glyph->glm_BlackWidth;
				//x+=(glyph->glm_Width >> 16);

				EReleaseInfo(&ofont->olf_EEngine,
					OT_GlyphMap8Bit,glyph,
					TAG_END);
			}
				
		}

	}

	ami_close_outline_font(ofont);
}