netsurf/amiga/font.c

/*
 * Copyright 2008 - 2011 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 "amiga/font.h"
#include "amiga/gui.h"
#include "amiga/utf8.h"
#include "amiga/object.h"
#include "amiga/options.h"
#include "css/css.h"
#include "css/utils.h"
#include "render/font.h"
#include "utils/log.h"
#include "utils/utf8.h"
#include "utils/utils.h"

#include <proto/diskfont.h>
#include <proto/exec.h>
#include <proto/graphics.h>
#include <proto/Picasso96API.h>
#include <proto/utility.h>

#include <diskfont/diskfonttag.h>
#include <diskfont/oterrors.h>
#include <graphics/rpattr.h>

#ifdef __amigaos4__
#include <graphics/blitattr.h>
#endif

#define NSA_UNICODE_FONT PLOT_FONT_FAMILY_COUNT

#define NSA_NORMAL 0
#define NSA_ITALIC 1
#define NSA_BOLD 2
#define NSA_BOLDITALIC 3

#define NSA_VALUE_BOLDX (1 << 12)
#define NSA_VALUE_BOLDY (1 << 12)
#define NSA_VALUE_SHEARSIN (1 << 14)
#define NSA_VALUE_SHEARCOS (1 << 16)

struct ami_font_node
{
	struct OutlineFont *font;
	char *bold;
	char *italic;
	char *bolditalic;
};

struct MinList *ami_font_list = NULL;
ULONG ami_devicedpi;

int32 ami_font_plot_glyph(struct OutlineFont *ofont, struct RastPort *rp,
		uint16 char1, uint16 char2, uint32 x, uint32 y, uint32 emwidth);
struct OutlineFont *ami_open_outline_font(const plot_font_style_t *fstyle, BOOL fallback);

static bool nsfont_width(const plot_font_style_t *fstyle,
	  const char *string, size_t length,
    int *width);
       
static bool 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 nsfont_split(const plot_font_style_t *fstyle,
	  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 plot_font_style_t *fstyle,
		const char *string, size_t length,
		int *width)
{
	*width = ami_unicode_text(NULL,string,length,fstyle,0,0);

	if(*width <= 0) *width == length; // fudge

	return true;
}

/**
 * Find the position in a string where an x coordinate falls.
 *
 * \param  fstyle       style for this text
 * \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 plot_font_style_t *fstyle,
		const char *string, size_t length,
		int x, size_t *char_offset, int *actual_x)
{
	struct TextExtent extent;
	struct TextFont *tfont;
	uint16 *utf16 = NULL, *outf16 = NULL;
	uint16 utf16next = NULL;
	FIXED kern = 0;
	struct OutlineFont *ofont, *ufont = NULL;
	struct GlyphMap *glyph;
	uint32 tx=0,i=0;
	size_t len, utf8len = 0;
	uint8 *utf8;
	uint32 co = 0;
	int utf16charlen;
	ULONG emwidth = (ULONG)(fstyle->size / FONT_SIZE_SCALE);
	int32 tempx;

	len = utf8_bounded_length(string, length);
	if(utf8_to_enc(string,"UTF-16",length,(char **)&utf16) != UTF8_CONVERT_OK) return false;
	outf16 = utf16;

	if(!(ofont = ami_open_outline_font(fstyle, FALSE))) return false;

	*char_offset = length;

	for(i=0;i<len;i++)
	{
		if (*utf16 < 0xD800 || 0xDFFF < *utf16)
			utf16charlen = 1;
		else
			utf16charlen = 2;

		utf8len = utf8_char_byte_length(string);

		utf16next = utf16[utf16charlen];

		tempx = ami_font_plot_glyph(ofont, NULL, *utf16, utf16next,
					0, 0, emwidth);

		if(tempx == 0)
		{
			if(ufont == NULL)
			{
				ufont = ami_open_outline_font(fstyle, TRUE);
			}

			if(ufont)
			{
				tempx = ami_font_plot_glyph(ufont, NULL, *utf16, utf16next,
							0, 0, emwidth);
			}
/*
			if(tempx == 0)
			{
				tempx = ami_font_plot_glyph(ofont, NULL, 0xfffd, utf16next,
							0, 0, emwidth);
			}
*/
		}

		if(x < (tx + tempx))
		{
			*actual_x = tx;
			i = len+1;
		}
		else
		{
			co += utf8len;
		}

		tx += tempx;
		string += utf8len;
		utf16 += utf16charlen;
	}

	if(co >= (length))
	{
		*actual_x = tx;
		co = length;
	}

	*char_offset = co;

	free(outf16);

	return true;
}


/**
 * Find where to split a string to make it fit a width.
 *
 * \param  fstyle       style for this text
 * \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 plot_font_style_t *fstyle,
		const char *string, size_t length,
		int x, size_t *char_offset, int *actual_x)
{
	struct TextExtent extent;
	ULONG co;
	char *ostr = string;
	struct TextFont *tfont;
	uint16 *utf16 = NULL,*outf16 = NULL;
	uint16 utf16next = 0;
	FIXED kern = 0;
	int utf16charlen = 0;
	struct OutlineFont *ofont, *ufont = NULL;
	struct GlyphMap *glyph;
	uint32 tx=0,i=0;
	size_t len;
	int utf8len, utf8clen = 0;
	int32 tempx = 0;
	ULONG emwidth = (ULONG)(fstyle->size / FONT_SIZE_SCALE);

	len = utf8_bounded_length(string, length);
	if(utf8_to_enc((char *)string,"UTF-16",length,(char **)&utf16) != UTF8_CONVERT_OK) return false;
	outf16 = utf16;
	if(!(ofont = ami_open_outline_font(fstyle, FALSE))) return false;

	*char_offset = 0;
	*actual_x = 0;

	for(i=0;i<len;i++)
	{
		utf8len = utf8_char_byte_length(string+utf8clen);

		if (*utf16 < 0xD800 || 0xDFFF < *utf16)
			utf16charlen = 1;
		else
			utf16charlen = 2;

		utf16next = utf16[utf16charlen];

		if(x < tx)
		{
			i = length+1;
		}
		else
		{
			if(string[utf8clen] == ' ') //*utf16 == 0x0020)
			{
				*actual_x = tx;
				*char_offset = utf8clen;
			}
		}

		tempx = ami_font_plot_glyph(ofont, NULL, *utf16, utf16next, 0, 0, emwidth);

		if(tempx == 0)
		{
			if(ufont == NULL)
			{
				ufont = ami_open_outline_font(fstyle, TRUE);
			}

			if(ufont)
			{
				tempx = ami_font_plot_glyph(ufont, NULL, *utf16, utf16next,
							0, 0, emwidth);
			}
/*
			if(tempx == 0)
			{
				tempx = ami_font_plot_glyph(ofont, NULL, 0xfffd, utf16next,
							0, 0, emwidth);
			}
*/
		}

		tx += tempx;
		utf16 += utf16charlen;
		utf8clen += utf8len;
	}

	free(outf16);

	return true;
}

/**
 * Search for a font in the list and load from disk if not present
 */
struct ami_font_node *ami_font_open(const char *font)
{
	struct nsObject *node;
	struct ami_font_node *nodedata;

	node = (struct nsObject *)FindIName((struct List *)ami_font_list, font);
	if(node) return node->objstruct;

	LOG(("Font cache miss: %s", font));

	nodedata = AllocVec(sizeof(struct ami_font_node), MEMF_PRIVATE | MEMF_CLEAR);

	node = AddObject(ami_font_list, AMINS_FONT);
	if(!node) return NULL;

	node->objstruct = nodedata;
	node->dtz_Node.ln_Name = strdup(font);

	nodedata->font = OpenOutlineFont(font, NULL, OFF_OPEN);
	if(!nodedata->font)
	{
		LOG(("Requested font not found: %s", font));
		warn_user("CompError", font);
		return NULL;
	}

	nodedata->bold = (char *)GetTagData(OT_BName, 0, nodedata->font->olf_OTagList);
	if(nodedata->bold)
		LOG(("Bold font defined for %s is %s", font, nodedata->bold));
	else
		LOG(("Warning: No designed bold font defined for %s", font));

	nodedata->italic = (char *)GetTagData(OT_IName, 0, nodedata->font->olf_OTagList);
	if(nodedata->italic)
		LOG(("Italic font defined for %s is %s", font, nodedata->italic));
	else
		LOG(("Warning: No designed italic font defined for %s", font));

	nodedata->bolditalic = (char *)GetTagData(OT_BIName, 0, nodedata->font->olf_OTagList);
	if(nodedata->bolditalic)
		LOG(("Bold-italic font defined for %s is %s", font, nodedata->bolditalic));
	else
		LOG(("Warning: No designed bold-italic font defined for %s", font));

	return nodedata;
}

/**
 * Open an outline font in the specified size and style
 *
 * \param fstyle font style structure
 * \param default open a default font instead of the one specified by fstyle
 * \return outline font or NULL on error
 */
struct OutlineFont *ami_open_outline_font(const plot_font_style_t *fstyle, BOOL fallback)
{
	struct ami_font_node *node;
	struct OutlineFont *ofont;
	char *fontname;
	ULONG ysize;
	int tstyle = 0;
	plot_font_generic_family_t fontfamily;
	ULONG emboldenx = 0;
	ULONG emboldeny = 0;
	ULONG shearsin = 0;
	ULONG shearcos = (1 << 16);

	if(fallback) fontfamily = NSA_UNICODE_FONT;
		else fontfamily = fstyle->family;

	switch(fontfamily)
	{
		case PLOT_FONT_FAMILY_SANS_SERIF:
			fontname = option_font_sans;
		break;
		case PLOT_FONT_FAMILY_SERIF:
			fontname = option_font_serif;
		break;
		case PLOT_FONT_FAMILY_MONOSPACE:
			fontname = option_font_mono;
		break;
		case PLOT_FONT_FAMILY_CURSIVE:
			fontname = option_font_cursive;
		break;
		case PLOT_FONT_FAMILY_FANTASY:
			fontname = option_font_fantasy;
		break;
		case NSA_UNICODE_FONT:
		default:
			fontname = option_font_unicode;
		break;
	}

	node = ami_font_open(fontname);
	if(!node) return NULL;

	if ((fstyle->flags & FONTF_ITALIC) || (fstyle->flags & FONTF_OBLIQUE))
		tstyle += NSA_ITALIC;

	if (fstyle->weight >= 700)
		tstyle += NSA_BOLD;

	switch(tstyle)
	{
		case NSA_ITALIC:
			if(node->italic)
			{
				node = ami_font_open(node->italic);
				if(!node) return NULL;
			}
			else
			{
				shearsin = NSA_VALUE_SHEARSIN;
				shearcos = NSA_VALUE_SHEARCOS;
			}
		break;

		case NSA_BOLD:
			if(node->bold)
			{
				node = ami_font_open(node->bold);
				if(!node) return NULL;
			}
			else
			{
				emboldenx = NSA_VALUE_BOLDX;
				emboldeny = NSA_VALUE_BOLDY;
			}
		break;

		case NSA_BOLDITALIC:
			if(node->bolditalic)
			{
				node = ami_font_open(node->bolditalic);
				if(!node) return NULL;
			}
			else
			{
				emboldenx = NSA_VALUE_BOLDX;
				emboldeny = NSA_VALUE_BOLDY;
				shearsin = NSA_VALUE_SHEARSIN;
				shearcos = NSA_VALUE_SHEARCOS;
			}
		break;
	}

	/* Scale to 16.16 fixed point */
	ysize = fstyle->size * ((1 << 16) / FONT_SIZE_SCALE);

	ofont = node->font;

	if(ESetInfo(&ofont->olf_EEngine,
			OT_DeviceDPI,   ami_devicedpi,
			OT_PointHeight, ysize,
			OT_EmboldenX,   emboldenx,
			OT_EmboldenY,   emboldeny,
			OT_ShearSin,    shearsin,
			OT_ShearCos,    shearcos,
			TAG_END) == OTERR_Success)
		return ofont;

	return NULL;
}

int32 ami_font_plot_glyph(struct OutlineFont *ofont, struct RastPort *rp,
		uint16 char1, uint16 char2, uint32 x, uint32 y, uint32 emwidth)
{
	struct GlyphMap *glyph;
	UBYTE *glyphbm;
	int32 char_advance = 0;
	FIXED kern = 0;

	if(ESetInfo(&ofont->olf_EEngine,
			OT_GlyphCode, char1,
			OT_GlyphCode2, char2,
			TAG_END) == OTERR_Success)
	{
		if(EObtainInfo(&ofont->olf_EEngine,
			OT_GlyphMap8Bit,&glyph,
			TAG_END) == 0)
		{
			glyphbm = glyph->glm_BitMap;
			if(!glyphbm) return 0;

			if(rp)
			{
				BltBitMapTags(BLITA_SrcX, glyph->glm_BlackLeft,
					BLITA_SrcY, glyph->glm_BlackTop,
					BLITA_DestX, x - glyph->glm_X0 + glyph->glm_BlackLeft,
					BLITA_DestY, y - glyph->glm_Y0 + glyph->glm_BlackTop,
					BLITA_Width, glyph->glm_BlackWidth,
					BLITA_Height, glyph->glm_BlackHeight,
					BLITA_Source, glyphbm,
					BLITA_SrcType, BLITT_ALPHATEMPLATE,
					BLITA_Dest, rp,
					BLITA_DestType, BLITT_RASTPORT,
					BLITA_SrcBytesPerRow, glyph->glm_BMModulo,
					TAG_DONE);
			}

			kern = 0;

			if(char2) EObtainInfo(&ofont->olf_EEngine,
								OT_TextKernPair, &kern,
								TAG_END);

			char_advance = (ULONG)(((glyph->glm_Width - kern) * emwidth) / 65536);

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

	return char_advance;
}

ULONG ami_unicode_text(struct RastPort *rp,const char *string,ULONG length,const plot_font_style_t *fstyle,ULONG dx, ULONG dy)
{
	uint16 *utf16 = NULL, *outf16 = NULL;
	uint16 utf16next = 0;
	int utf16charlen;
	struct OutlineFont *ofont, *ufont = NULL;
	ULONG i,gx,gy;
	UWORD posn;
	uint32 x=0;
	uint8 co = 0;
	int32 tempx = 0;
	ULONG emwidth = (ULONG)(fstyle->size / FONT_SIZE_SCALE);

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

	if(utf8_to_enc(string,"UTF-16",length,(char **)&utf16) != UTF8_CONVERT_OK) return 0;
	outf16 = utf16;
	if(!(ofont = ami_open_outline_font(fstyle, FALSE))) return 0;

	if(rp) SetRPAttrs(rp,RPTAG_APenColor,p96EncodeColor(RGBFB_A8B8G8R8,fstyle->foreground),TAG_DONE);

	while(*utf16 != 0)
	{
		if (*utf16 < 0xD800 || 0xDFFF < *utf16)
			utf16charlen = 1;
		else
			utf16charlen = 2;

		utf16next = utf16[utf16charlen];

		tempx = ami_font_plot_glyph(ofont, rp, *utf16, utf16next, dx + x, dy, emwidth);

		if(tempx == 0)
		{
			if(ufont == NULL)
			{
				ufont = ami_open_outline_font(fstyle, TRUE);
			}

			if(ufont)
			{
				tempx = ami_font_plot_glyph(ufont, rp, *utf16, utf16next,
							dx + x, dy, emwidth);
			}
/*
			if(tempx == 0)
			{
				tempx = ami_font_plot_glyph(ofont, rp, 0xfffd, utf16next,
							dx + x, dy, emwidth);
			}
*/
		}

		x += tempx;

		utf16 += utf16charlen;
	}

	free(outf16);
	return x;
}

void ami_init_fonts(void)
{
	ami_font_list = NewObjList();
}

void ami_close_fonts(void)
{
	LOG(("Cleaning up font cache"));
	FreeObjList(ami_font_list);
	ami_font_list = NULL;
}

void ami_font_close(struct ami_font_node *node)
{
	/* Called from FreeObjList if node type is AMINS_FONT */

	CloseOutlineFont(node->font, NULL);
}

void ami_font_setdevicedpi(int id)
{
	DisplayInfoHandle dih;
	struct DisplayInfo dinfo;
	Point dinfo_res;
	ULONG ydpi = option_amiga_ydpi;
	ULONG xdpi = option_amiga_ydpi;

	nscss_screen_dpi = INTTOFIX(option_amiga_ydpi);

	if(id)
	{
		if(dih = FindDisplayInfo(id))
		{
			if(GetDisplayInfoData(dih, &dinfo, sizeof(struct DisplayInfo),
				DTAG_DISP, 0))
			{
				dinfo_res = dinfo.Resolution;
				xdpi = (dinfo_res.x / dinfo_res.y) * ydpi;

				LOG(("XDPI = %ld, YDPI = %ld (DisplayInfo resolution %ld x %ld)",
					xdpi, ydpi, dinfo_res.x , dinfo_res.y));
			}
		}
	}

	ami_devicedpi = (xdpi << 16) | ydpi;
}