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stb_truetype.h
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stb_truetype.h
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// stb_truetype.h - v0.3 - public domain - 2009 Sean Barrett / RAD Game Tools
//
// This library processes TrueType files:
// parse files
// extract glyph metrics
// extract glyph shapes
// render glyphs to one-channel bitmaps with antialiasing (box filter)
//
// Todo:
// non-MS cmaps
// crashproof on bad data
// hinting
// subpixel positioning when rendering bitmap
// cleartype-style AA
//
// ADDITIONAL CONTRIBUTORS
//
// Mikko Mononen: compound shape support, more cmap formats
//
// VERSIONS
//
// 0.3 (2009-06-24) cmap fmt=12, compound shapes (MM)
// userdata, malloc-from-userdata, non-zero fill (STB)
// 0.2 (2009-03-11) Fix unsigned/signed char warnings
// 0.1 (2009-03-09) First public release
//
// USAGE
//
// Include this file in whatever places neeed to refer to it. In ONE C/C++
// file, write:
// #define STB_TRUETYPE_IMPLEMENTATION
// before the #include of this file. This expands out the actual
// implementation into that C/C++ file.
//
// Look at the header-file sections below for the API, but here's a quick skim:
//
// Simple 3D API (don't ship this, but it's fine for tools and quick start,
// and you can cut and paste from it to move to more advanced)
// stbtt_BakeFontBitmap() -- bake a font to a bitmap for use as texture
// stbtt_GetBakedQuad() -- compute quad to draw for a given char
//
// "Load" a font file from a memory buffer (you have to keep the buffer loaded)
// stbtt_InitFont()
// stbtt_GetFontOffsetForIndex() -- use for TTC font collections
//
// Render a unicode codepoint to a bitmap
// stbtt_GetCodepointBitmap() -- allocates and returns a bitmap
// stbtt_MakeCodepointBitmap() -- renders into bitmap you provide
// stbtt_GetCodepointBitmapBox() -- how big the bitmap must be
//
// Character advance/positioning
// stbtt_GetCodepointHMetrics()
// stbtt_GetFontVMetrics()
//
// NOTES
//
// The system uses the raw data found in the .ttf file without changing it
// and without building auxiliary data structures. This is a bit inefficient
// on little-endian systems (the data is big-endian), but assuming you're
// caching the bitmaps or glyph shapes this shouldn't be a big deal.
//
// It appears to be very hard to programmatically determine what font a
// given file is in a general way. I provide an API for this, but I don't
// recommend it.
//
//
// SOURCE STATISTICS (based on v0.3, 1800 LOC)
//
// Documentation & header file 350 LOC \___ 500 LOC documentation
// Sample code 140 LOC /
// Truetype parsing 580 LOC ---- 600 LOC TrueType
// Software rasterization 240 LOC \ .
// Curve tesselation 120 LOC \__ 500 LOC Bitmap creation
// Bitmap management 70 LOC /
// Baked bitmap interface 70 LOC /
// Font name matching & access 150 LOC ---- 150
// C runtime library abstraction 60 LOC ---- 60
//////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
////
//// SAMPLE PROGRAMS
////
//
// Incomplete text-in-3d-api example, which draws quads properly aligned to be lossless
//
#if 0
#define STB_TRUETYPE_IMPLEMENTATION // force following include to generate implementation
#include "stb_truetype.h"
char ttf_buffer[1<<20];
unsigned char temp_bitmap[512*512];
stbtt_chardata cdata[96]; // ASCII 32..126 is 95 glyphs
GLstbtt_uint ftex;
void my_stbtt_initfont(void)
{
fread(ttf_buffer, 1, 1<<20, fopen("c:/windows/fonts/times.ttf", "rb"));
stbtt_BakeFontBitmap(data,0, 32.0, temp_bitmap,512,512, 32,96, cdata); // no guarantee this fits!
// can free ttf_buffer at this point
glGenTextures(1, &ftex);
glBindTexture(GL_TEXTURE_2D, ftex);
glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, 512,512, 0, GL_ALPHA, GL_UNSIGNED_BYTE, temp_bitmap);
// can free temp_bitmap at this point
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
}
void my_stbtt_print(float x, float y, char *text)
{
// assume orthographic projection with units = screen pixels, origin at top left
glBindTexture(GL_TEXTURE_2D, ftex);
glBegin(GL_QUADS);
while (*text) {
if (*text >= 32 && *text < 128) {
stbtt_aligned_quad q;
stbtt_GetBakedQuad(cdata, 512,512, *text-32, &x,&y,&q,1);//1=opengl,0=old d3d
glTexCoord2f(q.s0,q.t1); glVertex2f(q.x0,q.y0);
glTexCoord2f(q.s1,q.t1); glVertex2f(q.x1,q.y0);
glTexCoord2f(q.s1,q.t0); glVertex2f(q.x1,q.y1);
glTexCoord2f(q.s0,q.t0); glVertex2f(q.x0,q.y1);
}
++text;
}
glEnd();
}
#endif
//
//
//////////////////////////////////////////////////////////////////////////////
//
// Complete program (this compiles): get a single bitmap, print as ASCII art
//
#if 0
#include <stdio.h>
#define STB_TRUETYPE_IMPLEMENTATION // force following include to generate implementation
#include "stb_truetype.h"
char ttf_buffer[1<<25];
int main(int argc, char **argv)
{
stbtt_fontinfo font;
unsigned char *bitmap;
int w,h,i,j,c = (argc > 1 ? atoi(argv[1]) : 'a'), s = (argc > 2 ? atoi(argv[2]) : 20);
fread(ttf_buffer, 1, 1<<25, fopen(argc > 3 ? argv[3] : "c:/windows/fonts/arialbd.ttf", "rb"));
stbtt_InitFont(&font, ttf_buffer, stbtt_GetFontOffsetForIndex(ttf_buffer,0));
bitmap = stbtt_GetCodepointBitmap(&font, 0,stbtt_ScaleForPixelHeight(&font, s), c, &w, &h, 0,0);
for (j=0; j < h; ++j) {
for (i=0; i < w; ++i)
putchar(" .:ioVM@"[bitmap[j*w+i]>>5]);
putchar('\n');
}
return 0;
}
#endif
//
// Output:
//
// .ii.
// @@@@@@.
// V@Mio@@o
// :i. V@V
// :oM@@M
// :@@@MM@M
// @@o o@M
// :@@. M@M
// @@@o@@@@
// :M@@V:@@.
//
//////////////////////////////////////////////////////////////////////////////
//
// Complete program: print "Hello World!" banner, with bugs
//
#if 0
int main(int arg, char **argv)
{
unsigned char screen[20][79];
int i,j, pos=0;
float scale;
char *text = "Heljo World!";
fread(buffer, 1, 1000000, fopen("c:/windows/fonts/arialbd.ttf", "rb"));
stbtt_InitFont(&font, buffer, 0);
scale = stbtt_ScaleForPixelHeight(&font, 16);
memset(screen, 0, sizeof(screen));
while (*text) {
int advance,lsb,x0,y0,x1,y1, newpos, baseline=13;
stbtt_GetCodepointHMetrics(&font, *text, &advance, &lsb);
stbtt_GetCodepointBitmapBox(&font, *text, scale,scale, &x0,&y0,&x1,&y1);
newpos = pos + (int) (lsb * scale) + x0;
stbtt_MakeCodepointBitmap(&font, &screen[baseline + y0][newpos], x1-x0,y1-y0, 79, scale,scale, *text);
// note that this stomps the old data, so where character boxes overlap (e.g. 'lj') it's wrong
// because this API is really for baking character bitmaps into textures
pos += (int) (advance * scale);
++text;
}
for (j=0; j < 20; ++j) {
for (i=0; i < 79; ++i)
putchar(" .:ioVM@"[screen[j][i]>>5]);
putchar('\n');
}
return 0;
}
#endif
//////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
////
//// INTEGRATION WITH RUNTIME LIBRARIES
////
#ifdef STB_TRUETYPE_IMPLEMENTATION
// #define your own (u)stbtt_int8/16/32 before including to override this
#ifndef stbtt_uint8
typedef unsigned char stbtt_uint8;
typedef signed char stbtt_int8;
typedef unsigned short stbtt_uint16;
typedef signed short stbtt_int16;
typedef unsigned int stbtt_uint32;
typedef signed int stbtt_int32;
#endif
typedef char stbtt__check_size32[sizeof(stbtt_int32)==4 ? 1 : -1];
typedef char stbtt__check_size16[sizeof(stbtt_int16)==2 ? 1 : -1];
// #define your own STBTT_sort() to override this to avoid qsort
#ifndef STBTT_sort
#include <stdlib.h>
#define STBTT_sort(data,num_items,item_size,compare_func) qsort(data,num_items,item_size,compare_func)
#endif
// #define your own STBTT_ifloor/STBTT_iceil() to avoid math.h
#ifndef STBTT_ifloor
#include <math.h>
#define STBTT_ifloor(x) ((int) floor(x))
#define STBTT_iceil(x) ((int) ceil(x))
#endif
// #define your own functions "STBTT_malloc" / "STBTT_free" to avoid malloc.h
#ifndef STBTT_malloc
#include <malloc.h>
#define STBTT_malloc(x,u) malloc(x)
#define STBTT_free(x,u) free(x)
#endif
#ifndef STBTT_assert
#include <assert.h>
#define STBTT_assert(x) assert(x)
#endif
#ifndef STBTT_strlen
#include <string.h>
#define STBTT_strlen(x) strlen(x)
#endif
//#ifndef STBTT_memcpy
//#include <memory.h>
#define STBTT_memcpy memcpy
#define STBTT_memset memset
//#endif
#endif
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
////
//// INTERFACE
////
////
#ifndef __STB_INCLUDE_STB_TRUETYPE_H__
#define __STB_INCLUDE_STB_TRUETYPE_H__
#ifdef __cplusplus
extern "C" {
#endif
//////////////////////////////////////////////////////////////////////////////
//
// TEXTURE BAKING API
//
// If you use this API, you only have to call two functions ever.
//
typedef struct
{
unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap
float xoff,yoff,xadvance;
} stbtt_bakedchar;
extern int stbtt_BakeFontBitmap(const unsigned char *data, int offset, // font location (use offset=0 for plain .ttf)
float pixel_height, // height of font in pixels
unsigned char *pixels, int pw, int ph, // bitmap to be filled in
int first_char, int num_chars, // characters to bake
stbtt_bakedchar *chardata); // you allocate this, it's num_chars long
// if return is positive, the first unused row of the bitmap
// if return is negative, returns the negative of the number of characters that fit
// if return is 0, no characters fit and no rows were used
// This uses a very crappy packing.
typedef struct
{
float x0,y0,s0,t0; // top-left
float x1,y1,s1,t1; // bottom-right
} stbtt_aligned_quad;
extern void stbtt_GetBakedQuad(stbtt_bakedchar *chardata, int pw, int ph, // same data as above
int char_index, // character to display
float *xpos, float *ypos, // pointers to current position in screen pixel space
stbtt_aligned_quad *q, // output: quad to draw
int opengl_fillrule); // true if opengl fill rule; false if DX9 or earlier
// Call GetBakedQuad with char_index = 'character - first_char', and it
// creates the quad you need to draw and advances the current position.
// It's inefficient; you might want to c&p it and optimize it.
//////////////////////////////////////////////////////////////////////////////
//
// FONT LOADING
//
//
extern int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index);
// Each .ttf file may have more than one font. Each has a sequential index
// number starting from 0. Call this function to get the font offset for a
// given index; it returns -1 if the index is out of range. A regular .ttf
// file will only define one font and it always be at offset 0, so it will
// return '0' for index 0, and -1 for all other indices. You can just skip
// this step if you know it's that kind of font.
// The following structure is defined publically so you can declare one on
// the stack or as a global or etc.
typedef struct
{
void *userdata;
unsigned char *data; // pointer to .ttf file
int fontstart; // offset of start of font
int numGlyphs; // number of glyphs, needed for range checking
int loca,head,glyf,hhea,hmtx; // table locations as offset from start of .ttf
int index_map; // a cmap mapping for our chosen character encoding
int indexToLocFormat; // format needed to map from glyph index to glyph
} stbtt_fontinfo;
extern int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset);
// Given an offset into the file that defines a font, this function builds
// the necessary cached info for the rest of the system. You must allocate
// the stbtt_fontinfo yourself, and stbtt_InitFont will fill it out. You don't
// need to do anything special to free it, because the contents are a pure
// cache with no additional data structures. Returns 0 on failure.
//////////////////////////////////////////////////////////////////////////////
//
// CHARACTER TO GLYPH-INDEX CONVERSIOn
int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint);
// If you're going to perform multiple operations on the same character
// and you want a speed-up, call this function with the character you're
// going to process, then use glyph-based functions instead of the
// codepoint-based functions.
//////////////////////////////////////////////////////////////////////////////
//
// CHARACTER PROPERTIES
//
extern float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float pixels);
// computes a scale factor to produce a font whose "height" is 'pixels' tall.
// Height is measured as the distance from the highest ascender to the lowest
// descender; in other words, it's equivalent to calling stbtt_GetFontVMetrics
// and computing:
// scale = pixels / (ascent - descent)
// so if you prefer to measure height by the ascent only, use a similar calculation.
extern void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap);
// ascent is the coordinate above the baseline the font extends; descent
// is the coordinate below the baseline the font extends (i.e. it is typically negative)
// lineGap is the spacing between one row's descent and the next row's ascent...
// so you should advance the vertical position by "*ascent - *descent + *lineGap"
// these are expressed in unscaled coordinates
extern void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing);
// leftSideBearing is the offset from the current horizontal position to the left edge of the character
// advanceWidth is the offset from the current horizontal position to the next horizontal position
// these are expressed in unscaled coordinates
extern int stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2);
// an additional amount to add to the 'advance' value between ch1 and ch2
// @TODO; for now always returns 0!
extern int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1);
// Gets the bounding box of the visible part of the glyph, in unscaled coordinates
extern void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing);
extern int stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2);
extern int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);
// as above, but takes one or more glyph indices for greater efficiency
//////////////////////////////////////////////////////////////////////////////
//
// GLYPH SHAPES (you probably don't need these, but they have to go before
// the bitmaps for C declaration-order reasons)
//
#ifndef STBTT_vmove // you can predefine these to use different values (but why?)
enum {
STBTT_vmove=1,
STBTT_vline,
STBTT_vcurve
};
#endif
#ifndef stbtt_vertex // you can predefine this to use different values
// (we share this with other code at RAD)
#define stbtt_vertex_type short // can't use stbtt_int16 because that's not visible in the header file
typedef struct
{
stbtt_vertex_type x,y,cx,cy;
unsigned char type,padding;
} stbtt_vertex;
#endif
extern int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices);
extern int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **vertices);
// returns # of vertices and fills *vertices with the pointer to them
// these are expressed in "unscaled" coordinates
extern void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *vertices);
// frees the data allocated above
//////////////////////////////////////////////////////////////////////////////
//
// BITMAP RENDERING
//
extern void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata);
// frees the bitmap allocated below
extern unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
// allocates a large-enough single-channel 8bpp bitmap and renders the
// specified character/glyph at the specified scale into it, with
// antialiasing. 0 is no coverage (transparent), 255 is fully covered (opaque).
// *width & *height are filled out with the width & height of the bitmap,
// which is stored left-to-right, top-to-bottom.
//
// xoff/yoff are the offset it pixel space from the glyph origin to the top-left of the bitmap
extern void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint);
// the same as above, but you pass in storage for the bitmap in the form
// of 'output', with row spacing of 'out_stride' bytes. the bitmap is
// clipped to out_w/out_h bytes. call the next function to get the
// height and width and positioning info
extern void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
// get the bbox of the bitmap centered around the glyph origin; so the
// bitmap width is ix1-ix0, height is iy1-iy0, and location to place
// the bitmap top left is (leftSideBearing*scale,iy0).
// (Note that the bitmap uses y-increases-down, but the shape uses
// y-increases-up, so CodepointBitmapBox and CodepointBox are inverted.)
extern unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff);
extern void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
extern void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph);
//extern void stbtt_get_true_bbox(stbtt_vertex *vertices, int num_verts, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
// @TODO: don't expose this structure
typedef struct
{
int w,h,stride;
unsigned char *pixels;
} stbtt__bitmap;
extern void stbtt_Rasterize(stbtt__bitmap *result, float flatness_in_pixels, stbtt_vertex *vertices, int num_verts, float scale_x, float scale_y, int x_off, int y_off, int invert, void *userdata);
//////////////////////////////////////////////////////////////////////////////
//
// Finding the right font...
//
// You should really just solve this offline, keep your own tables
// of what font is what, and don't try to get it out of the .ttf file.
// That's because getting it out of the .ttf file is really hard, because
// the names in the file can appear in many possible encodings, in many
// possible languages, and e.g. if you need a case-insensitive comparison,
// the details of that depend on the encoding & language in a complex way
// (actually underspecified in truetype, but also gigantic).
//
// But you can use the provided functions in two possible ways:
// stbtt_FindMatchingFont() will use *case-sensitive* comparisons on
// unicode-encoded names to try to find the font you want;
// you can run this before calling stbtt_InitFont()
//
// stbtt_GetFontNameString() lets you get any of the various strings
// from the file yourself and do your own comparisons on them.
// You have to have called stbtt_InitFont() first.
extern int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags);
// returns the offset (not index) of the font that matches, or -1 if none
// if you use STBTT_MACSTYLE_DONTCARE, use a font name like "Arial Bold".
// if you use any other flag, use a font name like "Arial"; this checks
// the 'macStyle' header field; i don't know if fonts set this consistently
#define STBTT_MACSTYLE_DONTCARE 0
#define STBTT_MACSTYLE_BOLD 1
#define STBTT_MACSTYLE_ITALIC 2
#define STBTT_MACSTYLE_UNDERSCORE 4
#define STBTT_MACSTYLE_NONE 8 // <= not same as 0, this makes us check the bitfield is 0
extern int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2);
// returns 1/0 whether the first string interpreted as utf8 is identical to
// the second string interpreted as big-endian utf16... useful for strings from next func
extern char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID);
// returns the string (which may be big-endian double byte, e.g. for unicode)
// and puts the length in bytes in *length.
//
// some of the values for the IDs are below; for more see the truetype spec:
// http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6name.html
// http://www.microsoft.com/typography/otspec/name.htm
enum { // platformID
STBTT_PLATFORM_ID_UNICODE =0,
STBTT_PLATFORM_ID_MAC =1,
STBTT_PLATFORM_ID_ISO =2,
STBTT_PLATFORM_ID_MICROSOFT =3
};
enum { // encodingID for STBTT_PLATFORM_ID_UNICODE
STBTT_UNICODE_EID_UNICODE_1_0 =0,
STBTT_UNICODE_EID_UNICODE_1_1 =1,
STBTT_UNICODE_EID_ISO_10646 =2,
STBTT_UNICODE_EID_UNICODE_2_0_BMP=3,
STBTT_UNICODE_EID_UNICODE_2_0_FULL=4,
};
enum { // encodingID for STBTT_PLATFORM_ID_MICROSOFT
STBTT_MS_EID_SYMBOL =0,
STBTT_MS_EID_UNICODE_BMP =1,
STBTT_MS_EID_SHIFTJIS =2,
STBTT_MS_EID_UNICODE_FULL =10,
};
enum { // encodingID for STBTT_PLATFORM_ID_MAC; same as Script Manager codes
STBTT_MAC_EID_ROMAN =0, STBTT_MAC_EID_ARABIC =4,
STBTT_MAC_EID_JAPANESE =1, STBTT_MAC_EID_HEBREW =5,
STBTT_MAC_EID_CHINESE_TRAD =2, STBTT_MAC_EID_GREEK =6,
STBTT_MAC_EID_KOREAN =3, STBTT_MAC_EID_RUSSIAN =7,
};
enum { // languageID for STBTT_PLATFORM_ID_MICROSOFT; same as LCID...
// problematic because there are e.g. 16 english LCIDs and 16 arabic LCIDs
STBTT_MS_LANG_ENGLISH =0x0409, STBTT_MS_LANG_ITALIAN =0x0410,
STBTT_MS_LANG_CHINESE =0x0804, STBTT_MS_LANG_JAPANESE =0x0411,
STBTT_MS_LANG_DUTCH =0x0413, STBTT_MS_LANG_KOREAN =0x0412,
STBTT_MS_LANG_FRENCH =0x040c, STBTT_MS_LANG_RUSSIAN =0x0419,
STBTT_MS_LANG_GERMAN =0x0407, STBTT_MS_LANG_SPANISH =0x0409,
STBTT_MS_LANG_HEBREW =0x040d, STBTT_MS_LANG_SWEDISH =0x041D,
};
enum { // languageID for STBTT_PLATFORM_ID_MAC
STBTT_MAC_LANG_ENGLISH =0 , STBTT_MAC_LANG_JAPANESE =11,
STBTT_MAC_LANG_ARABIC =12, STBTT_MAC_LANG_KOREAN =23,
STBTT_MAC_LANG_DUTCH =4 , STBTT_MAC_LANG_RUSSIAN =32,
STBTT_MAC_LANG_FRENCH =1 , STBTT_MAC_LANG_SPANISH =6 ,
STBTT_MAC_LANG_GERMAN =2 , STBTT_MAC_LANG_SWEDISH =5 ,
STBTT_MAC_LANG_HEBREW =10, STBTT_MAC_LANG_CHINESE_SIMPLIFIED =33,
STBTT_MAC_LANG_ITALIAN =3 , STBTT_MAC_LANG_CHINESE_TRAD =19,
};
#ifdef __cplusplus
}
#endif
#endif // __STB_INCLUDE_STB_TRUETYPE_H__
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
////
//// IMPLEMENTATION
////
////
#ifdef STB_TRUETYPE_IMPLEMENTATION
//////////////////////////////////////////////////////////////////////////
//
// accessors to parse data from file
//
// on platforms that don't allow misaligned reads, if we want to allow
// truetype fonts that aren't padded to alignment, define ALLOW_UNALIGNED_TRUETYPE
#define ttBYTE(p) (* (stbtt_uint8 *) (p))
#define ttCHAR(p) (* (stbtt_int8 *) (p))
#define ttFixed(p) ttLONG(p)
#if defined(STB_TRUETYPE_BIGENDIAN) && !defined(ALLOW_UNALIGNED_TRUETYPE)
#define ttUSHORT(p) (* (stbtt_uint16 *) (p))
#define ttSHORT(p) (* (stbtt_int16 *) (p))
#define ttULONG(p) (* (stbtt_uint32 *) (p))
#define ttLONG(p) (* (stbtt_int32 *) (p))
#else
stbtt_uint16 ttUSHORT(const stbtt_uint8 *p) { return p[0]*256 + p[1]; }
stbtt_int16 ttSHORT(const stbtt_uint8 *p) { return p[0]*256 + p[1]; }
stbtt_uint32 ttULONG(const stbtt_uint8 *p) { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; }
stbtt_int32 ttLONG(const stbtt_uint8 *p) { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; }
#endif
#define stbtt_tag4(p,c0,c1,c2,c3) ((p)[0] == (c0) && (p)[1] == (c1) && (p)[2] == (c2) && (p)[3] == (c3))
#define stbtt_tag(p,str) stbtt_tag4(p,str[0],str[1],str[2],str[3])
static int stbtt__isfont(const stbtt_uint8 *font)
{
// check the version number
if (stbtt_tag(font, "1")) return 1; // TrueType 1
if (stbtt_tag(font, "typ1")) return 1; // TrueType with type 1 font -- we don't support this!
if (stbtt_tag(font, "OTTO")) return 1; // OpenType with CFF
if (stbtt_tag4(font, 0,1,0,0)) return 1; // OpenType 1.0
return 0;
}
// @OPTIMIZE: binary search
static stbtt_uint32 stbtt__find_table(stbtt_uint8 *data, stbtt_uint32 fontstart, char *tag)
{
stbtt_int32 num_tables = ttUSHORT(data+fontstart+4);
stbtt_uint32 tabledir = fontstart + 12;
stbtt_int32 i;
for (i=0; i < num_tables; ++i) {
stbtt_uint32 loc = tabledir + 16*i;
if (stbtt_tag(data+loc+0, tag))
return ttULONG(data+loc+8);
}
return 0;
}
int stbtt_GetFontOffsetForIndex(const unsigned char *font_collection, int index)
{
// if it's just a font, there's only one valid index
if (stbtt__isfont(font_collection))
return index == 0 ? 0 : -1;
// check if it's a TTC
if (stbtt_tag(font_collection, "ttcf")) {
// version 1?
if (ttULONG(font_collection+4) == 0x00010000 || ttULONG(font_collection+4) == 0x00020000) {
stbtt_int32 n = ttLONG(font_collection+8);
if (index >= n)
return -1;
return ttULONG(font_collection+12+index*14);
}
}
return -1;
}
int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data2, int fontstart)
{
stbtt_uint8 *data = (stbtt_uint8 *) data2;
stbtt_uint32 cmap, t;
stbtt_int32 i,numTables;
info->data = data;
info->fontstart = fontstart;
cmap = stbtt__find_table(data, fontstart, "cmap");
info->loca = stbtt__find_table(data, fontstart, "loca");
info->head = stbtt__find_table(data, fontstart, "head");
info->glyf = stbtt__find_table(data, fontstart, "glyf");
info->hhea = stbtt__find_table(data, fontstart, "hhea");
info->hmtx = stbtt__find_table(data, fontstart, "hmtx");
if (!cmap || !info->loca || !info->head || !info->glyf || !info->hhea || !info->hmtx)
return 0;
t = stbtt__find_table(data, fontstart, "maxp");
if (t)
info->numGlyphs = ttUSHORT(data+t+4);
else
info->numGlyphs = 0xffff;
// find a cmap encoding table we understand *now* to avoid searching
// later. (todo: could make this installable)
// the same regardless of glyph.
numTables = ttUSHORT(data + cmap + 2);
info->index_map = 0;
for (i=0; i < numTables; ++i) {
stbtt_uint32 encoding_record = cmap + 4 + 8 * i;
// find an encoding we understand:
switch(ttUSHORT(data+encoding_record)) {
case STBTT_PLATFORM_ID_MICROSOFT:
switch (ttUSHORT(data+encoding_record+2)) {
case STBTT_MS_EID_UNICODE_BMP:
case STBTT_MS_EID_UNICODE_FULL:
// MS/Unicode
info->index_map = cmap + ttULONG(data+encoding_record+4);
break;
}
break;
}
}
if (info->index_map == 0)
return 0;
info->indexToLocFormat = ttUSHORT(data+info->head + 50);
return 1;
}
int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint)
{
stbtt_uint8 *data = info->data;
stbtt_uint32 index_map = info->index_map;
stbtt_uint16 format = ttUSHORT(data + index_map + 0);
if (format == 0) { // apple byte encoding
stbtt_int32 bytes = ttUSHORT(data + index_map + 2);
if (unicode_codepoint < bytes-6)
return ttBYTE(data + index_map + 6 + unicode_codepoint);
return 0;
} else if (format == 6) {
stbtt_uint32 first = ttUSHORT(data + index_map + 6);
stbtt_uint32 count = ttUSHORT(data + index_map + 8);
if ((stbtt_uint32) unicode_codepoint >= first && (stbtt_uint32) unicode_codepoint < first+count)
return ttUSHORT(data + index_map + 10 + (unicode_codepoint - first)*2);
return 0;
} else if (format == 2) {
STBTT_assert(0); // @TODO: high-byte mapping for japanese/chinese/korean
return 0;
} else if (format == 4) { // standard mapping for windows fonts: binary search collection of ranges
stbtt_uint16 segcount = ttUSHORT(data+index_map+6) >> 1;
stbtt_uint16 searchRange = ttUSHORT(data+index_map+8) >> 1;
stbtt_uint16 entrySelector = ttUSHORT(data+index_map+10);
stbtt_uint16 rangeShift = ttUSHORT(data+index_map+12) >> 1;
stbtt_uint16 item, offset, start, end;
// do a binary search of the segments
stbtt_uint32 endCount = index_map + 14;
stbtt_uint32 search = endCount;
if (unicode_codepoint > 0xffff)
return 0;
// they lie from endCount .. endCount + segCount
// but searchRange is the nearest power of two, so...
if (unicode_codepoint >= ttUSHORT(data + search + rangeShift*2))
search += rangeShift*2;
// now decrement to bias correctly to find smallest
search -= 2;
while (entrySelector) {
stbtt_uint16 start, end;
searchRange >>= 1;
start = ttUSHORT(data + search + 2 + segcount*2 + 2);
end = ttUSHORT(data + search + 2);
start = ttUSHORT(data + search + searchRange*2 + segcount*2 + 2);
end = ttUSHORT(data + search + searchRange*2);
if (unicode_codepoint > end)
search += searchRange*2;
--entrySelector;
}
search += 2;
item = (stbtt_uint16) ((search - endCount) >> 1);
STBTT_assert(unicode_codepoint <= ttUSHORT(data + endCount + 2*item));
start = ttUSHORT(data + index_map + 14 + segcount*2 + 2 + 2*item);
end = ttUSHORT(data + index_map + 14 + 2 + 2*item);
if (unicode_codepoint < start)
return 0;
offset = ttUSHORT(data + index_map + 14 + segcount*6 + 2 + 2*item);
if (offset == 0)
return unicode_codepoint + ttSHORT(data + index_map + 14 + segcount*4 + 2 + 2*item);
return ttUSHORT(data + offset + (unicode_codepoint-start)*2 + index_map + 14 + segcount*6 + 2 + 2*item);
} else if (format == 12) {
stbtt_uint16 ngroups = ttUSHORT(data+index_map+6);
stbtt_int32 low,high;
stbtt_uint16 g = 0;
low = 0; high = (stbtt_int32)ngroups;
// Binary search the right group.
while (low <= high) {
stbtt_int32 mid = low + ((high-low) >> 1); // rounds down, so low <= mid < high
stbtt_uint32 start_char = ttULONG(data+index_map+16+mid*12);
stbtt_uint32 end_char = ttULONG(data+index_map+16+mid*12+4);
if ((stbtt_uint32) unicode_codepoint < start_char)
high = mid-1;
else if ((stbtt_uint32) unicode_codepoint > end_char)
low = mid+1;
else {
stbtt_uint32 start_glyph = ttULONG(data+index_map+16+mid*12+8);
return start_glyph + unicode_codepoint-start_char;
}
}
return 0; // not found
}
// @TODO
STBTT_assert(0);
return 0;
}
int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices)
{
return stbtt_GetGlyphShape(info, stbtt_FindGlyphIndex(info, unicode_codepoint), vertices);
}
static void stbtt_setvertex(stbtt_vertex *v, stbtt_uint8 type, stbtt_int16 x, stbtt_int16 y, stbtt_int16 cx, stbtt_int16 cy)
{
v->type = type;
v->x = x;
v->y = y;
v->cx = cx;
v->cy = cy;
}
static int stbtt__GetGlyfOffset(const stbtt_fontinfo *info, int glyph_index)
{
int g1,g2;
if (glyph_index >= info->numGlyphs) return -1; // glyph index out of range
if (info->indexToLocFormat >= 2) return -1; // unknown index->glyph map format
if (info->indexToLocFormat == 0) {
g1 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2) * 2;
g2 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2 + 2) * 2;
} else {
g1 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4);
g2 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4 + 4);
}
return g1==g2 ? -1 : g1; // if length is 0, return -1
}
int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1)
{
int g = stbtt__GetGlyfOffset(info, glyph_index);
if (g < 0) return 0;
if (x0) *x0 = ttSHORT(info->data + g + 2);
if (y0) *y0 = ttSHORT(info->data + g + 4);
if (x1) *x1 = ttSHORT(info->data + g + 6);
if (y1) *y1 = ttSHORT(info->data + g + 8);
return 1;
}
int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1)
{
return stbtt_GetGlyphBox(info, stbtt_FindGlyphIndex(info,codepoint), x0,y0,x1,y1);
}
int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
{
stbtt_int16 numberOfContours;
stbtt_uint8 *endPtsOfContours;
stbtt_uint8 *data = info->data;
stbtt_vertex *vertices=0;
int num_vertices=0;
int g = stbtt__GetGlyfOffset(info, glyph_index);
*pvertices = NULL;
if (g < 0) return 0;
numberOfContours = ttSHORT(data + g);
if (numberOfContours > 0) {
stbtt_uint8 flags=0,flagcount;
stbtt_int32 ins, i,j=0,m,n, next_move, was_off=0, off;
stbtt_int16 x,y,cx,cy,sx,sy;
stbtt_uint8 *points;
endPtsOfContours = (data + g + 10);
ins = ttUSHORT(data + g + 10 + numberOfContours * 2);
points = data + g + 10 + numberOfContours * 2 + 2 + ins;
n = 1+ttUSHORT(endPtsOfContours + numberOfContours*2-2);
m = n + numberOfContours; // a loose bound on how many vertices we might need
vertices = (stbtt_vertex *) STBTT_malloc(m * sizeof(vertices[0]), info->userdata);
if (vertices == 0)
return 0;
next_move = 0;
flagcount=0;
// in first pass, we load uninterpreted data into the allocated array
// above, shifted to the end of the array so we won't overwrite it when
// we create our final data starting from the front
off = m - n; // starting offset for uninterpreted data, regardless of how m ends up being calculated
// first load flags
for (i=0; i < n; ++i) {
if (flagcount == 0) {
flags = *points++;
if (flags & 8)
flagcount = *points++;
} else
--flagcount;
vertices[off+i].type = flags;
}
// now load x coordinates
x=0;
for (i=0; i < n; ++i) {
flags = vertices[off+i].type;
if (flags & 2) {
stbtt_int16 dx = *points++;
x += (flags & 16) ? dx : -dx; // ???
} else {
if (!(flags & 16)) {
x = x + (stbtt_int16) (points[0]*256 + points[1]);
points += 2;
}
}
vertices[off+i].x = x;
}
// now load y coordinates
y=0;
for (i=0; i < n; ++i) {
flags = vertices[off+i].type;
if (flags & 4) {
stbtt_int16 dy = *points++;
y += (flags & 32) ? dy : -dy; // ???
} else {
if (!(flags & 32)) {
y = y + (stbtt_int16) (points[0]*256 + points[1]);
points += 2;
}
}
vertices[off+i].y = y;
}
// now convert them to our format
num_vertices=0;
sx = sy = cx = cy = 0;
for (i=0; i < n; ++i) {
flags = vertices[off+i].type;
x = (stbtt_int16) vertices[off+i].x;
y = (stbtt_int16) vertices[off+i].y;
if (next_move == i) {
// when we get to the end, we have to close the shape explicitly
if (i != 0) {
if (was_off)
stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve,sx,sy,cx,cy);
else
stbtt_setvertex(&vertices[num_vertices++], STBTT_vline,sx,sy,0,0);
}
// now start the new one
stbtt_setvertex(&vertices[num_vertices++], STBTT_vmove,x,y,0,0);
next_move = 1 + ttUSHORT(endPtsOfContours+j*2);
++j;
was_off = 0;
sx = x;
sy = y;
} else {
if (!(flags & 1)) { // if it's a curve
if (was_off) // two off-curve control points in a row means interpolate an on-curve midpoint
stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+x)>>1, (cy+y)>>1, cx, cy);
cx = x;
cy = y;
was_off = 1;
} else {
if (was_off)
stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, x,y, cx, cy);
else
stbtt_setvertex(&vertices[num_vertices++], STBTT_vline, x,y,0,0);
was_off = 0;
}
}
}
if (i != 0) {
if (was_off)
stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve,sx,sy,cx,cy);
else
stbtt_setvertex(&vertices[num_vertices++], STBTT_vline,sx,sy,0,0);
}
} else if (numberOfContours == -1) {
// Compound shapes.
int more = 1;
stbtt_uint8 *comp = data + g + 10;
num_vertices = 0;
vertices = 0;