nuclear@0: /* nuclear@0: libdrawtext - a simple library for fast text rendering in OpenGL nuclear@0: Copyright (C) 2011-2012 John Tsiombikas nuclear@0: nuclear@0: This program is free software: you can redistribute it and/or modify nuclear@0: it under the terms of the GNU Lesser General Public License as published by nuclear@0: the Free Software Foundation, either version 3 of the License, or nuclear@0: (at your option) any later version. nuclear@0: nuclear@0: This program is distributed in the hope that it will be useful, nuclear@0: but WITHOUT ANY WARRANTY; without even the implied warranty of nuclear@0: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the nuclear@0: GNU Lesser General Public License for more details. nuclear@0: nuclear@0: You should have received a copy of the GNU Lesser General Public License nuclear@0: along with this program. If not, see . nuclear@0: */ nuclear@0: #ifndef TEXT_H_ nuclear@0: #define TEXT_H_ nuclear@0: nuclear@0: #include nuclear@0: #include nuclear@0: nuclear@0: struct dtx_font; nuclear@0: struct dtx_glyphmap; nuclear@0: nuclear@0: /* draw buffering modes */ nuclear@0: enum { nuclear@0: DTX_NBF, /* unbuffered */ nuclear@0: DTX_LBF, /* line buffered */ nuclear@0: DTX_FBF /* fully buffered */ nuclear@0: }; nuclear@0: nuclear@0: struct dtx_box { nuclear@0: float x, y; nuclear@0: float width, height; nuclear@0: }; nuclear@0: nuclear@0: #ifdef __cplusplus nuclear@0: extern "C" { nuclear@0: #endif nuclear@0: nuclear@0: /* Open a truetype/opentype/whatever font. nuclear@0: * nuclear@0: * If sz is non-zero, the default ASCII glyphmap at the requested point size is nuclear@0: * automatically created as well, and ready to use. nuclear@0: * nuclear@0: * To use other unicode ranges and different font sizes you must first call nuclear@0: * dtx_prepare or dtx_prepare_range before issuing any drawing calls, otherwise nuclear@0: * nothing will be rendered. nuclear@0: */ nuclear@0: struct dtx_font *dtx_open_font(const char *fname, int sz); nuclear@0: void dtx_close_font(struct dtx_font *fnt); nuclear@0: nuclear@0: /* prepare an ASCII glyphmap for the specified font size */ nuclear@0: void dtx_prepare(struct dtx_font *fnt, int sz); nuclear@0: /* prepare an arbitrary unicode range glyphmap for the specified font size */ nuclear@0: void dtx_prepare_range(struct dtx_font *fnt, int sz, int cstart, int cend); nuclear@0: nuclear@0: /* Finds the glyphmap that contains the specified character code and matches the requested size nuclear@0: * Returns null if it hasn't been created (you should call dtx_prepare/dtx_prepare_range). nuclear@0: */ nuclear@0: struct dtx_glyphmap *dtx_get_font_glyphmap(struct dtx_font *fnt, int sz, int code); nuclear@0: nuclear@0: /* Finds the glyphmap that contains the specified unicode range and matches the requested font size nuclear@0: * Will automatically generate one if it can't find it. nuclear@0: */ nuclear@0: struct dtx_glyphmap *dtx_get_font_glyphmap_range(struct dtx_font *fnt, int sz, int cstart, int cend); nuclear@0: nuclear@0: /* Creates and returns a glyphmap for a particular unicode range and font size. nuclear@0: * The generated glyphmap is added to the font's list of glyphmaps. nuclear@0: */ nuclear@0: struct dtx_glyphmap *dtx_create_glyphmap_range(struct dtx_font *fnt, int sz, int cstart, int cend); nuclear@0: /* free a glyphmap */ nuclear@0: void dtx_free_glyphmap(struct dtx_glyphmap *gmap); nuclear@0: nuclear@0: /* returns a pointer to the raster image of a glyphmap (1 byte per pixel grayscale) */ nuclear@0: unsigned char *dtx_get_glyphmap_image(struct dtx_glyphmap *gmap); nuclear@0: /* returns the width of the glyphmap image in pixels */ nuclear@0: int dtx_get_glyphmap_width(struct dtx_glyphmap *gmap); nuclear@0: /* returns the height of the glyphmap image in pixels */ nuclear@0: int dtx_get_glyphmap_height(struct dtx_glyphmap *gmap); nuclear@0: nuclear@0: /* The following functions can be used even when the library is compiled without nuclear@0: * freetype support. (TODO) nuclear@0: */ nuclear@0: struct dtx_glyphmap *dtx_load_glyphmap(const char *fname); nuclear@0: struct dtx_glyphmap *dtx_load_glyphmap_stream(FILE *fp); nuclear@0: int dtx_save_glyphmap(const char *fname, const struct dtx_glyphmap *gmap); nuclear@0: int dtx_save_glyphmap_stream(FILE *fp, const struct dtx_glyphmap *gmap); nuclear@0: nuclear@0: nuclear@0: /* ---- rendering ---- */ nuclear@0: nuclear@0: /* before drawing anything this function must set the font to use */ nuclear@0: void dtx_use_font(struct dtx_font *fnt, int sz); nuclear@0: nuclear@0: /* sets the buffering mode nuclear@0: * - DTX_NBF: every call to dtx_string gets rendered immediately. nuclear@0: * - DTX_LBF: renders when the buffer is full or the string contains a newline. nuclear@0: * - DTX_FBF: renders only when the buffer is full (you must call dtx_flush explicitly). nuclear@0: */ nuclear@0: void dtx_draw_buffering(int mode); nuclear@0: nuclear@0: /* Sets the vertex attribute indices to use for passing vertex and texture coordinate nuclear@0: * data. By default both are -1 which means you don't have to use a shader, and if you nuclear@0: * do they are accessible through gl_Vertex and gl_MultiTexCoord0, as usual. nuclear@0: * nuclear@0: * NOTE: If you are using OpenGL ES 2.x or OpenGL >= 3.1 pure (non-compatibility) context nuclear@0: * you must specify valid attribute indices. nuclear@0: */ nuclear@0: void dtx_vertex_attribs(int vert_attr, int tex_attr); nuclear@0: nuclear@0: /* draws a single glyph at the origin */ nuclear@0: void dtx_glyph(int code); nuclear@0: /* draws a utf-8 string starting at the origin. \n \r and \t are handled appropriately. */ nuclear@0: void dtx_string(const char *str); nuclear@0: nuclear@0: void dtx_printf(const char *fmt, ...); nuclear@0: nuclear@0: /* render any pending glyphs (see dtx_draw_buffering) */ nuclear@0: void dtx_flush(void); nuclear@0: nuclear@0: nuclear@0: /* ---- encodings ---- */ nuclear@0: nuclear@0: /* returns a pointer to the next character in a utf-8 stream */ nuclear@0: char *dtx_utf8_next_char(char *str); nuclear@0: nuclear@0: /* returns the unicode character codepoint of the utf-8 character starting at str */ nuclear@0: int dtx_utf8_char_code(const char *str); nuclear@0: nuclear@0: /* returns the number of bytes of the utf-8 character starting at str */ nuclear@0: int dtx_utf8_nbytes(const char *str); nuclear@0: nuclear@0: /* returns the number of utf-8 character in a zero-terminated utf-8 string */ nuclear@0: int dtx_utf8_char_count(const char *str); nuclear@0: nuclear@0: /* Converts a unicode code-point to a utf-8 character by filling in the buffer nuclear@0: * passed at the second argument, and returns the number of bytes taken by that nuclear@0: * utf-8 character. nuclear@0: * It's valid to pass a null buffer pointer, in which case only the byte count is nuclear@0: * returned (useful to figure out how much memory to allocate for a buffer). nuclear@0: */ nuclear@0: size_t dtx_utf8_from_char_code(int code, char *buf); nuclear@0: nuclear@0: /* Converts a unicode utf-16 wchar_t string to utf-8, filling in the buffer passed nuclear@0: * at the second argument. Returns the size of the resulting string in bytes. nuclear@0: * nuclear@0: * It's valid to pass a null buffer pointer, in which case only the size gets nuclear@0: * calculated and returned, which is useful for figuring out how much memory to nuclear@0: * allocate for the utf-8 buffer. nuclear@0: */ nuclear@0: size_t dtx_utf8_from_string(const wchar_t *str, char *buf); nuclear@0: nuclear@0: nuclear@0: /* ---- metrics ---- */ nuclear@0: float dtx_line_height(void); nuclear@0: float dtx_baseline(void); nuclear@0: nuclear@0: /* rendered dimensions of a single glyph */ nuclear@0: void dtx_glyph_box(int code, struct dtx_box *box); nuclear@0: float dtx_glyph_width(int code); nuclear@0: float dtx_glyph_height(int code); nuclear@0: nuclear@0: /* rendered dimensions of a string */ nuclear@0: void dtx_string_box(const char *str, struct dtx_box *box); nuclear@0: float dtx_string_width(const char *str); nuclear@0: float dtx_string_height(const char *str); nuclear@0: nuclear@0: /* returns the horizontal position of the n-th character of the rendered string nuclear@0: * (useful for placing cursors) nuclear@0: */ nuclear@0: float dtx_char_pos(const char *str, int n); nuclear@0: nuclear@0: int dtx_char_at_pt(const char *str, float pt); nuclear@0: nuclear@0: #ifdef __cplusplus nuclear@0: } nuclear@0: #endif nuclear@0: nuclear@0: #endif /* TEXT_H_ */